Open Access Publications
From research on the visual systems of turtles, to the perception of faces with or without makeup, to transaccadic perception and perceptual cycles in the brain– VPixx hardware and software solutions have supported research in vision science and beyond for over 20 years. We are immensely proud of the discoveries and accomplishments of our customers across the world.
On this page you will find a non-exhaustive list of peer-reviewed, open access publications citing VPixx tools dating back to 2003. Browse the list or use the tag filter to search for specific products. Note that we report the device used in the paper according to the authors; this may not accurately reflect the specific model of device used (e.g., VIEWPixx vs. VIEWPixx /3D). Nor do we guarantee the accuracy of published content. Please contact our team at [email protected] if you have any questions about a specific paper.
Curious about a specific application of our tools? Can’t find what you are looking for? Our staff scientists are happy to discuss paradigms and protocols using our equipment by email or video chat. Please contact us with your questions.
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Use the search tool below to search for specific terms among the titles, authors and abstracts in our library.
1.
Taubert, Jessica; Japee, Shruti
Real Face Value: The Processing of Naturalistic Facial Expressions in the Macaque Inferior Temporal Cortex Journal Article
In: Journal of Cognitive Neuroscience, pp. 1–17, 2024, ISSN: 0898-929X, 1530-8898.
Abstract | Links | BibTeX | Tags: DATAPixx
@article{taubert_real_2024,
title = {Real Face Value: The Processing of Naturalistic Facial Expressions in the Macaque Inferior Temporal Cortex},
author = {Jessica Taubert and Shruti Japee},
url = {https://direct.mit.edu/jocn/article/doi/10.1162/jocn_a_02108/119171/Real-Face-Value-The-Processing-of-Naturalistic},
doi = {10.1162/jocn_a_02108},
issn = {0898-929X, 1530-8898},
year = {2024},
date = {2024-01-01},
urldate = {2024-01-30},
journal = {Journal of Cognitive Neuroscience},
pages = {1–17},
abstract = {Abstract
For primates, expressions of fear are thought to be powerful social signals. In laboratory settings, faces with fearful expressions have reliably evoked valence effects in inferior temporal cortex. However, because macaques use so called “fear grins” in a variety of different contexts, the deeper question is whether the macaque inferior temporal cortex is tuned to the prototypical fear grin, or to conspecifics signaling fear? In this study, we combined neuroimaging with the results of a behavioral task to investigate how macaques encode a wide variety of fearful facial expressions. In Experiment 1, we identified two sets of macaque face stimuli using different approaches; we selected faces based on the emotional context (i.e., calm vs. fearful), and we selected faces based on the engagement of action units (i.e., neutral vs. fear grins). We also included human faces in Experiment 1. Then, using fMRI, we found that the faces selected based on context elicited a larger valence effect in the inferior temporal cortex than faces selected based on visual appearance. Furthermore, human facial expressions only elicited weak valence effects. These observations were further supported by the results of a two-alternative, forced-choice task (Experiment 2), suggesting that fear grins vary in their perceived pleasantness. Collectively, these findings indicate that the macaque inferior temporal cortex is more involved in social intelligence than commonly assumed, encoding emergent properties in naturalistic face stimuli that transcend basic visual features. These results demand a rethinking of theories surrounding the function and operationalization of primate inferior temporal cortex.},
keywords = {DATAPixx},
pubstate = {published},
tppubtype = {article}
}
Abstract
For primates, expressions of fear are thought to be powerful social signals. In laboratory settings, faces with fearful expressions have reliably evoked valence effects in inferior temporal cortex. However, because macaques use so called “fear grins” in a variety of different contexts, the deeper question is whether the macaque inferior temporal cortex is tuned to the prototypical fear grin, or to conspecifics signaling fear? In this study, we combined neuroimaging with the results of a behavioral task to investigate how macaques encode a wide variety of fearful facial expressions. In Experiment 1, we identified two sets of macaque face stimuli using different approaches; we selected faces based on the emotional context (i.e., calm vs. fearful), and we selected faces based on the engagement of action units (i.e., neutral vs. fear grins). We also included human faces in Experiment 1. Then, using fMRI, we found that the faces selected based on context elicited a larger valence effect in the inferior temporal cortex than faces selected based on visual appearance. Furthermore, human facial expressions only elicited weak valence effects. These observations were further supported by the results of a two-alternative, forced-choice task (Experiment 2), suggesting that fear grins vary in their perceived pleasantness. Collectively, these findings indicate that the macaque inferior temporal cortex is more involved in social intelligence than commonly assumed, encoding emergent properties in naturalistic face stimuli that transcend basic visual features. These results demand a rethinking of theories surrounding the function and operationalization of primate inferior temporal cortex.
For primates, expressions of fear are thought to be powerful social signals. In laboratory settings, faces with fearful expressions have reliably evoked valence effects in inferior temporal cortex. However, because macaques use so called “fear grins” in a variety of different contexts, the deeper question is whether the macaque inferior temporal cortex is tuned to the prototypical fear grin, or to conspecifics signaling fear? In this study, we combined neuroimaging with the results of a behavioral task to investigate how macaques encode a wide variety of fearful facial expressions. In Experiment 1, we identified two sets of macaque face stimuli using different approaches; we selected faces based on the emotional context (i.e., calm vs. fearful), and we selected faces based on the engagement of action units (i.e., neutral vs. fear grins). We also included human faces in Experiment 1. Then, using fMRI, we found that the faces selected based on context elicited a larger valence effect in the inferior temporal cortex than faces selected based on visual appearance. Furthermore, human facial expressions only elicited weak valence effects. These observations were further supported by the results of a two-alternative, forced-choice task (Experiment 2), suggesting that fear grins vary in their perceived pleasantness. Collectively, these findings indicate that the macaque inferior temporal cortex is more involved in social intelligence than commonly assumed, encoding emergent properties in naturalistic face stimuli that transcend basic visual features. These results demand a rethinking of theories surrounding the function and operationalization of primate inferior temporal cortex.
2.
Levi, Aaron J.; Zhao, Yuan; Park, Il Memming; Huk, Alexander C.
Sensory and Choice Responses in MT Distinct from Motion Encoding Journal Article
In: Journal of Neuroscience, vol. 43, no. 12, pp. 2090–2103, 2023, ISSN: 0270-6474, 1529-2401, (Publisher: Society for Neuroscience Section: Research Articles).
Abstract | Links | BibTeX | Tags: DATAPixx, PROPixx
@article{levi_sensory_2023,
title = {Sensory and Choice Responses in MT Distinct from Motion Encoding},
author = {Aaron J. Levi and Yuan Zhao and Il Memming Park and Alexander C. Huk},
url = {https://www.jneurosci.org/content/43/12/2090},
doi = {10.1523/JNEUROSCI.0267-22.2023},
issn = {0270-6474, 1529-2401},
year = {2023},
date = {2023-03-01},
urldate = {2023-12-21},
journal = {Journal of Neuroscience},
volume = {43},
number = {12},
pages = {2090–2103},
abstract = {The macaque middle temporal (MT) area is well known for its visual motion selectivity and relevance to motion perception, but the possibility of it also reflecting higher-level cognitive functions has largely been ignored. We tested for effects of task performance distinct from sensory encoding by manipulating subjects' temporal evidence-weighting strategy during a direction discrimination task while performing electrophysiological recordings from groups of MT neurons in rhesus macaques (one male, one female). This revealed multiple components of MT responses that were, surprisingly, not interpretable as behaviorally relevant modulations of motion encoding, or as bottom-up consequences of the readout of motion direction from MT. The time-varying motion-driven responses of MT were strongly affected by our strategic manipulation—but with time courses opposite the subjects' temporal weighting strategies. Furthermore, large choice-correlated signals were represented in population activity distinct from its motion responses, with multiple phases that lagged psychophysical readout and even continued after the stimulus (but which preceded motor responses). In summary, a novel experimental manipulation of strategy allowed us to control the time course of readout to challenge the correlation between sensory responses and choices, and population-level analyses of simultaneously recorded ensembles allowed us to identify strong signals that were so distinct from direction encoding that conventional, single-neuron-centric analyses could not have revealed or properly characterized them. Together, these approaches revealed multiple cognitive contributions to MT responses that are task related but not functionally relevant to encoding or decoding of motion for psychophysical direction discrimination, providing a new perspective on the assumed status of MT as a simple sensory area.
SIGNIFICANCE STATEMENT This study extends understanding of the middle temporal (MT) area beyond its representation of visual motion. Combining multineuron recordings, population-level analyses, and controlled manipulation of task strategy, we exposed signals that depended on changes in temporal weighting strategy, but did not manifest as feedforward effects on behavior. This was demonstrated by (1) an inverse relationship between temporal dynamics of behavioral readout and sensory encoding, (2) a choice-correlated signal that always lagged the stimulus time points most correlated with decisions, and (3) a distinct choice-correlated signal after the stimulus. These findings invite re-evaluation of MT for functions outside of its established sensory role and highlight the power of experimenter-controlled changes in temporal strategy, coupled with recording and analysis approaches that transcend the single-neuron perspective.},
note = {Publisher: Society for Neuroscience
Section: Research Articles},
keywords = {DATAPixx, PROPixx},
pubstate = {published},
tppubtype = {article}
}
The macaque middle temporal (MT) area is well known for its visual motion selectivity and relevance to motion perception, but the possibility of it also reflecting higher-level cognitive functions has largely been ignored. We tested for effects of task performance distinct from sensory encoding by manipulating subjects' temporal evidence-weighting strategy during a direction discrimination task while performing electrophysiological recordings from groups of MT neurons in rhesus macaques (one male, one female). This revealed multiple components of MT responses that were, surprisingly, not interpretable as behaviorally relevant modulations of motion encoding, or as bottom-up consequences of the readout of motion direction from MT. The time-varying motion-driven responses of MT were strongly affected by our strategic manipulation—but with time courses opposite the subjects' temporal weighting strategies. Furthermore, large choice-correlated signals were represented in population activity distinct from its motion responses, with multiple phases that lagged psychophysical readout and even continued after the stimulus (but which preceded motor responses). In summary, a novel experimental manipulation of strategy allowed us to control the time course of readout to challenge the correlation between sensory responses and choices, and population-level analyses of simultaneously recorded ensembles allowed us to identify strong signals that were so distinct from direction encoding that conventional, single-neuron-centric analyses could not have revealed or properly characterized them. Together, these approaches revealed multiple cognitive contributions to MT responses that are task related but not functionally relevant to encoding or decoding of motion for psychophysical direction discrimination, providing a new perspective on the assumed status of MT as a simple sensory area.
SIGNIFICANCE STATEMENT This study extends understanding of the middle temporal (MT) area beyond its representation of visual motion. Combining multineuron recordings, population-level analyses, and controlled manipulation of task strategy, we exposed signals that depended on changes in temporal weighting strategy, but did not manifest as feedforward effects on behavior. This was demonstrated by (1) an inverse relationship between temporal dynamics of behavioral readout and sensory encoding, (2) a choice-correlated signal that always lagged the stimulus time points most correlated with decisions, and (3) a distinct choice-correlated signal after the stimulus. These findings invite re-evaluation of MT for functions outside of its established sensory role and highlight the power of experimenter-controlled changes in temporal strategy, coupled with recording and analysis approaches that transcend the single-neuron perspective.
SIGNIFICANCE STATEMENT This study extends understanding of the middle temporal (MT) area beyond its representation of visual motion. Combining multineuron recordings, population-level analyses, and controlled manipulation of task strategy, we exposed signals that depended on changes in temporal weighting strategy, but did not manifest as feedforward effects on behavior. This was demonstrated by (1) an inverse relationship between temporal dynamics of behavioral readout and sensory encoding, (2) a choice-correlated signal that always lagged the stimulus time points most correlated with decisions, and (3) a distinct choice-correlated signal after the stimulus. These findings invite re-evaluation of MT for functions outside of its established sensory role and highlight the power of experimenter-controlled changes in temporal strategy, coupled with recording and analysis approaches that transcend the single-neuron perspective.
3.
Wutz, Andreas; Zazio, Agnese; Weisz, Nathan
Oscillatory Bursts in Parietal Cortex Reflect Dynamic Attention between Multiple Objects and Ensembles Journal Article
In: Journal of Neuroscience, vol. 40, no. 36, pp. 6927–6937, 2020, ISSN: 0270-6474, 1529-2401, (Publisher: Society for Neuroscience Section: Research Articles).
Abstract | Links | BibTeX | Tags: DATAPixx, PROPixx, TRACKPixx3
@article{wutz_oscillatory_2020,
title = {Oscillatory Bursts in Parietal Cortex Reflect Dynamic Attention between Multiple Objects and Ensembles},
author = {Andreas Wutz and Agnese Zazio and Nathan Weisz},
url = {https://www.jneurosci.org/content/40/36/6927},
doi = {10.1523/JNEUROSCI.0231-20.2020},
issn = {0270-6474, 1529-2401},
year = {2020},
date = {2020-09-01},
urldate = {2024-01-16},
journal = {Journal of Neuroscience},
volume = {40},
number = {36},
pages = {6927–6937},
abstract = {The visual system uses two complimentary strategies to process multiple objects simultaneously within a scene and update their spatial positions in real time. It either uses selective attention to individuate a complex, dynamic scene into a few focal objects (i.e., object individuation), or it represents multiple objects as an ensemble by distributing attention more globally across the scene (i.e., ensemble grouping). Neural oscillations may be a key signature for focal object individuation versus distributed ensemble grouping, because they are thought to regulate neural excitability over visual areas through inhibitory control mechanisms. We recorded whole-head MEG data during a multiple-object tracking paradigm, in which human participants (13 female, 11 male) switched between different instructions for object individuation and ensemble grouping on different trials. The stimuli, responses, and the demand to keep track of multiple spatial locations over time were held constant between the two conditions. We observed increased α-band power (9-13 Hz) packed into oscillatory bursts in bilateral inferior parietal cortex during multiple-object processing. Single-trial analysis revealed greater burst occurrences on object individuation versus ensemble grouping trials. By contrast, we found no differences using standard analyses on across-trials averaged α-band power. Moreover, the bursting effects occurred only below/at, but not above, the typical capacity limits for multiple-object processing (at ∼4 objects). Our findings reveal the real-time neural correlates underlying the dynamic processing of multiple-object scenarios, which are modulated by grouping strategies and capacity. They support a rhythmic, α-pulsed organization of dynamic attention to multiple objects and ensembles.
SIGNIFICANCE STATEMENT Dynamic multiple-object scenarios are an important problem in real-world and computer vision. They require keeping track of multiple objects as they move through space and time. Such problems can be solved in two ways: One can individuate a scene object by object, or alternatively group objects into ensembles. We observed greater occurrences of α-oscillatory burst events in parietal cortex for processing objects versus ensembles and below/at versus above processing capacity. These results demonstrate a unique top-down mechanism by which the brain dynamically adjusts its computational level between objects and ensembles. They help to explain how the brain copes with its capacity limitations in real-time environments and may lead the way to technological innovations for time-critical video analysis in computer vision.},
note = {Publisher: Society for Neuroscience
Section: Research Articles},
keywords = {DATAPixx, PROPixx, TRACKPixx3},
pubstate = {published},
tppubtype = {article}
}
The visual system uses two complimentary strategies to process multiple objects simultaneously within a scene and update their spatial positions in real time. It either uses selective attention to individuate a complex, dynamic scene into a few focal objects (i.e., object individuation), or it represents multiple objects as an ensemble by distributing attention more globally across the scene (i.e., ensemble grouping). Neural oscillations may be a key signature for focal object individuation versus distributed ensemble grouping, because they are thought to regulate neural excitability over visual areas through inhibitory control mechanisms. We recorded whole-head MEG data during a multiple-object tracking paradigm, in which human participants (13 female, 11 male) switched between different instructions for object individuation and ensemble grouping on different trials. The stimuli, responses, and the demand to keep track of multiple spatial locations over time were held constant between the two conditions. We observed increased α-band power (9-13 Hz) packed into oscillatory bursts in bilateral inferior parietal cortex during multiple-object processing. Single-trial analysis revealed greater burst occurrences on object individuation versus ensemble grouping trials. By contrast, we found no differences using standard analyses on across-trials averaged α-band power. Moreover, the bursting effects occurred only below/at, but not above, the typical capacity limits for multiple-object processing (at ∼4 objects). Our findings reveal the real-time neural correlates underlying the dynamic processing of multiple-object scenarios, which are modulated by grouping strategies and capacity. They support a rhythmic, α-pulsed organization of dynamic attention to multiple objects and ensembles.
SIGNIFICANCE STATEMENT Dynamic multiple-object scenarios are an important problem in real-world and computer vision. They require keeping track of multiple objects as they move through space and time. Such problems can be solved in two ways: One can individuate a scene object by object, or alternatively group objects into ensembles. We observed greater occurrences of α-oscillatory burst events in parietal cortex for processing objects versus ensembles and below/at versus above processing capacity. These results demonstrate a unique top-down mechanism by which the brain dynamically adjusts its computational level between objects and ensembles. They help to explain how the brain copes with its capacity limitations in real-time environments and may lead the way to technological innovations for time-critical video analysis in computer vision.
SIGNIFICANCE STATEMENT Dynamic multiple-object scenarios are an important problem in real-world and computer vision. They require keeping track of multiple objects as they move through space and time. Such problems can be solved in two ways: One can individuate a scene object by object, or alternatively group objects into ensembles. We observed greater occurrences of α-oscillatory burst events in parietal cortex for processing objects versus ensembles and below/at versus above processing capacity. These results demonstrate a unique top-down mechanism by which the brain dynamically adjusts its computational level between objects and ensembles. They help to explain how the brain copes with its capacity limitations in real-time environments and may lead the way to technological innovations for time-critical video analysis in computer vision.
4.
Aldrich, Amelia; Hibbard, Paul; Wilkins, Arnold
Vision and Hyper-Responsiveness in Migraine Journal Article
In: Vision, vol. 3, no. 4, pp. 62, 2019, ISSN: 2411-5150, (Number: 4 Publisher: Multidisciplinary Digital Publishing Institute).
Abstract | Links | BibTeX | Tags: DATAPixx, RESPONSEPixx
@article{aldrich_vision_2019,
title = {Vision and Hyper-Responsiveness in Migraine},
author = {Amelia Aldrich and Paul Hibbard and Arnold Wilkins},
url = {https://www.mdpi.com/2411-5150/3/4/62},
doi = {10.3390/vision3040062},
issn = {2411-5150},
year = {2019},
date = {2019-12-01},
urldate = {2023-12-21},
journal = {Vision},
volume = {3},
number = {4},
pages = {62},
abstract = {We investigated contrast processing in relation to visual comfort from coloured light in individuals with migraine. In Experiment 1, 24 individuals who experienced migraine with aura (MA), 15 migraine without aura (MO), and 23 healthy controls, identified which of four patterns, one in each quadrant, had the greatest contrast. Although there were no significant differences between groups, contrast discrimination was superior in the visual field affected by aura in all eight participants in whom the aura was consistently lateralised. In Experiment 2, 20 participants without aura and 20 controls selected comfortable light with a chromaticity close to the daylight (Planckian) locus, whilst 20 individuals with aura chose more strongly saturated colours, mostly distant from the locus. In Experiment 3, nine participants with consistently unilateral aura undertook the contrast discrimination task wearing (a) lenses that provided a comfortable colour of light and (b) grey lenses of similar transmission. With grey lenses, seven of the nine individuals with unilateral aura showed a superior performance in the affected field, as before. With lenses providing a comfortable colour, however, the performance was relatively poor for the nine individuals with unilateral aura, but not for the 10 controls. This was the case in both visual fields. The cortical hyper-responsiveness with which migraine is associated may improve the perception of contrast. The perception is poorer (and more normal) with ophthalmic lenses having a comfortable colour.},
note = {Number: 4
Publisher: Multidisciplinary Digital Publishing Institute},
keywords = {DATAPixx, RESPONSEPixx},
pubstate = {published},
tppubtype = {article}
}
We investigated contrast processing in relation to visual comfort from coloured light in individuals with migraine. In Experiment 1, 24 individuals who experienced migraine with aura (MA), 15 migraine without aura (MO), and 23 healthy controls, identified which of four patterns, one in each quadrant, had the greatest contrast. Although there were no significant differences between groups, contrast discrimination was superior in the visual field affected by aura in all eight participants in whom the aura was consistently lateralised. In Experiment 2, 20 participants without aura and 20 controls selected comfortable light with a chromaticity close to the daylight (Planckian) locus, whilst 20 individuals with aura chose more strongly saturated colours, mostly distant from the locus. In Experiment 3, nine participants with consistently unilateral aura undertook the contrast discrimination task wearing (a) lenses that provided a comfortable colour of light and (b) grey lenses of similar transmission. With grey lenses, seven of the nine individuals with unilateral aura showed a superior performance in the affected field, as before. With lenses providing a comfortable colour, however, the performance was relatively poor for the nine individuals with unilateral aura, but not for the 10 controls. This was the case in both visual fields. The cortical hyper-responsiveness with which migraine is associated may improve the perception of contrast. The perception is poorer (and more normal) with ophthalmic lenses having a comfortable colour.
5.
Kim, Byounghoon; Kenchappa, Shobha Channabasappa; Sunkara, Adhira; Chang, Ting-Yu; Thompson, Lowell; Doudlah, Raymond; Rosenberg, Ari
Real-time experimental control using network-based parallel processing Journal Article
In: eLife, vol. 8, pp. e40231, 2019, ISSN: 2050-084X, (Publisher: eLife Sciences Publications, Ltd).
Abstract | Links | BibTeX | Tags: 3DPixx, 3DPolarizer, DATAPixx, PROPixx, VIEWPixx3D
@article{kim_real-time_2019,
title = {Real-time experimental control using network-based parallel processing},
author = {Byounghoon Kim and Shobha Channabasappa Kenchappa and Adhira Sunkara and Ting-Yu Chang and Lowell Thompson and Raymond Doudlah and Ari Rosenberg},
editor = {Sacha B Nelson and Michael J Frank and Sacha B Nelson and Niraj Desai},
url = {https://doi.org/10.7554/eLife.40231},
doi = {10.7554/eLife.40231},
issn = {2050-084X},
year = {2019},
date = {2019-02-01},
urldate = {2024-01-17},
journal = {eLife},
volume = {8},
pages = {e40231},
abstract = {Modern neuroscience research often requires the coordination of multiple processes such as stimulus generation, real-time experimental control, as well as behavioral and neural measurements. The technical demands required to simultaneously manage these processes with high temporal fidelity is a barrier that limits the number of labs performing such work. Here we present an open-source, network-based parallel processing framework that lowers this barrier. The Real-Time Experimental Control with Graphical User Interface (REC-GUI) framework offers multiple advantages: (i) a modular design that is agnostic to coding language(s) and operating system(s) to maximize experimental flexibility and minimize researcher effort, (ii) simple interfacing to connect multiple measurement and recording devices, (iii) high temporal fidelity by dividing task demands across CPUs, and (iv) real-time control using a fully customizable and intuitive GUI. We present applications for human, non-human primate, and rodent studies which collectively demonstrate that the REC-GUI framework facilitates technically demanding, behavior-contingent neuroscience research. Editorial note: This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (see decision letter).},
note = {Publisher: eLife Sciences Publications, Ltd},
keywords = {3DPixx, 3DPolarizer, DATAPixx, PROPixx, VIEWPixx3D},
pubstate = {published},
tppubtype = {article}
}
Modern neuroscience research often requires the coordination of multiple processes such as stimulus generation, real-time experimental control, as well as behavioral and neural measurements. The technical demands required to simultaneously manage these processes with high temporal fidelity is a barrier that limits the number of labs performing such work. Here we present an open-source, network-based parallel processing framework that lowers this barrier. The Real-Time Experimental Control with Graphical User Interface (REC-GUI) framework offers multiple advantages: (i) a modular design that is agnostic to coding language(s) and operating system(s) to maximize experimental flexibility and minimize researcher effort, (ii) simple interfacing to connect multiple measurement and recording devices, (iii) high temporal fidelity by dividing task demands across CPUs, and (iv) real-time control using a fully customizable and intuitive GUI. We present applications for human, non-human primate, and rodent studies which collectively demonstrate that the REC-GUI framework facilitates technically demanding, behavior-contingent neuroscience research. Editorial note: This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (see decision letter).
6.
Brown, Alyse; Corner, Molly; Crewther, David; Crewther, Sheila
Age Related Decline in Cortical Multifocal Flash VEP: Latency Increases Shown to Be Predominately Magnocellular Journal Article
In: Frontiers in Aging Neuroscience, vol. 10, 2019, ISSN: 1663-4365.
Abstract | Links | BibTeX | Tags: DATAPixx, VPixxProgram
@article{brown_age_2019,
title = {Age Related Decline in Cortical Multifocal Flash VEP: Latency Increases Shown to Be Predominately Magnocellular},
author = {Alyse Brown and Molly Corner and David Crewther and Sheila Crewther},
url = {https://www.frontiersin.org/articles/10.3389/fnagi.2018.00430},
issn = {1663-4365},
year = {2019},
date = {2019-01-01},
urldate = {2023-12-21},
journal = {Frontiers in Aging Neuroscience},
volume = {10},
abstract = {As the visual system ages, flicker sensitivity decreases and the latencies of cortical visual evoked potentials (VEP) increase. However, the extent to which these effects reflect age-related changes in the magnocellular (M) and or parvocellular (P) pathways remain unclear. Here, we investigated the relation between flicker fusion frequencies and VEP non-linearities induced by rapid stimulation, as a function of age over 6 decades. The approach, using Wiener kernel analysis of multifocal flash (mf)VEP, allows the extraction of signatures of both M and P processing and hence establishing a neural basis of the known decline in flicker fusion threshold. We predicted that, in a sample of 86 participants, age would be associated with a latency increase in early mfVEP response components and that flicker fusion thresholds, for both low and high contrast stimuli, would relate to the temporal efficiency of the M-generated VEP component amplitudes. As expected, flicker fusion frequency reduced with age, while latencies of early second order peaks of the mfVEP increased with age, but M temporal efficiency (amplitude ratio of first to second order peaks) was not strongly age-related. The steepest increases in latency were associated with the M dominated K2.1 (second order first slice) N70 components recorded at low and high contrast (6.7 and 5.9 ms/decade, respectively). Interestingly, significant age-related latency shifts were not observed in the first order responses. Significant decreases in amplitude were found in multiple first and second order components up to 30 years of age, after which they remained relatively constant. Thus, aging and decline in visual function appears to be most closely related to the response latencies of non-linearities generated by the M pathway.},
keywords = {DATAPixx, VPixxProgram},
pubstate = {published},
tppubtype = {article}
}
As the visual system ages, flicker sensitivity decreases and the latencies of cortical visual evoked potentials (VEP) increase. However, the extent to which these effects reflect age-related changes in the magnocellular (M) and or parvocellular (P) pathways remain unclear. Here, we investigated the relation between flicker fusion frequencies and VEP non-linearities induced by rapid stimulation, as a function of age over 6 decades. The approach, using Wiener kernel analysis of multifocal flash (mf)VEP, allows the extraction of signatures of both M and P processing and hence establishing a neural basis of the known decline in flicker fusion threshold. We predicted that, in a sample of 86 participants, age would be associated with a latency increase in early mfVEP response components and that flicker fusion thresholds, for both low and high contrast stimuli, would relate to the temporal efficiency of the M-generated VEP component amplitudes. As expected, flicker fusion frequency reduced with age, while latencies of early second order peaks of the mfVEP increased with age, but M temporal efficiency (amplitude ratio of first to second order peaks) was not strongly age-related. The steepest increases in latency were associated with the M dominated K2.1 (second order first slice) N70 components recorded at low and high contrast (6.7 and 5.9 ms/decade, respectively). Interestingly, significant age-related latency shifts were not observed in the first order responses. Significant decreases in amplitude were found in multiple first and second order components up to 30 years of age, after which they remained relatively constant. Thus, aging and decline in visual function appears to be most closely related to the response latencies of non-linearities generated by the M pathway.
7.
Han, Shui'Er; Lukaszewski, Raphael; Alais, David
Continuous flash suppression operates in local spatial zones: Effects of mask size and contrast Journal Article
In: Vision Research, vol. 154, pp. 105–114, 2019, ISSN: 0042-6989.
Abstract | Links | BibTeX | Tags: DATAPixx
@article{han_continuous_2019,
title = {Continuous flash suppression operates in local spatial zones: Effects of mask size and contrast},
author = {Shui'Er Han and Raphael Lukaszewski and David Alais},
url = {https://www.sciencedirect.com/science/article/pii/S0042698918302414},
doi = {10.1016/j.visres.2018.11.006},
issn = {0042-6989},
year = {2019},
date = {2019-01-01},
urldate = {2024-01-02},
journal = {Vision Research},
volume = {154},
pages = {105–114},
abstract = {Continuous flash suppression (CFS) is a technique in which presenting one eye with a dynamic Mondrian sequence prevents a low-contrast target in the other eye from being perceived for many seconds. Frequently used to study unconscious visual processing, CFS bears many similarities with binocular rivalry (BR), another popular dichoptic stimulation technique. It is therefore puzzling that the effect of mask size and contrast seem to differ between CFS and BR. To resolve this discrepancy, we conducted a systematic investigation on the effects of mask size and contrast in CFS. Also, building on findings from BR, we asked if the collinearity of the contours in the Mondrian masker play a role in CFS suppression. Our results showed a robust effect of mask contrast on suppression durations, and an effect of mask size that depended on collinearity. Specifically, higher mask contrasts produced longer suppression regardless of collinearity and mask size. Mask size, on the other hand, had little effect on suppression when collinearity was low and it weakened suppression when collinearity is high. These observations parallel prior findings in BR, further substantiating the close link between the two paradigms and demonstrating the usefulness of a shared explanatory framework describing both phenomena.},
keywords = {DATAPixx},
pubstate = {published},
tppubtype = {article}
}
Continuous flash suppression (CFS) is a technique in which presenting one eye with a dynamic Mondrian sequence prevents a low-contrast target in the other eye from being perceived for many seconds. Frequently used to study unconscious visual processing, CFS bears many similarities with binocular rivalry (BR), another popular dichoptic stimulation technique. It is therefore puzzling that the effect of mask size and contrast seem to differ between CFS and BR. To resolve this discrepancy, we conducted a systematic investigation on the effects of mask size and contrast in CFS. Also, building on findings from BR, we asked if the collinearity of the contours in the Mondrian masker play a role in CFS suppression. Our results showed a robust effect of mask contrast on suppression durations, and an effect of mask size that depended on collinearity. Specifically, higher mask contrasts produced longer suppression regardless of collinearity and mask size. Mask size, on the other hand, had little effect on suppression when collinearity was low and it weakened suppression when collinearity is high. These observations parallel prior findings in BR, further substantiating the close link between the two paradigms and demonstrating the usefulness of a shared explanatory framework describing both phenomena.
8.
Luna, Raúl; Serrano-Pedraza, Ignacio
Temporal frequency modulates the strength of the inhibitory interaction between motion sensors tuned to coarse and fine scales Journal Article
In: Journal of Vision, vol. 18, no. 13, pp. 17, 2018, ISSN: 1534-7362.
Abstract | Links | BibTeX | Tags: DATAPixx
@article{luna_temporal_2018,
title = {Temporal frequency modulates the strength of the inhibitory interaction between motion sensors tuned to coarse and fine scales},
author = {Raúl Luna and Ignacio Serrano-Pedraza},
url = {https://doi.org/10.1167/18.13.17},
doi = {10.1167/18.13.17},
issn = {1534-7362},
year = {2018},
date = {2018-12-01},
urldate = {2024-01-18},
journal = {Journal of Vision},
volume = {18},
number = {13},
pages = {17},
abstract = {The perceived direction of motion of a brief moving fine scale pattern reverses when a static coarse scale pattern is added to it (Henning & Derrington, 1988). This impairment in motion direction discrimination has been explained by the inhibitory interaction between motion sensors tuned to fine and coarse scales. This interaction depends on the particular spatial frequencies mixed, the size of the stimulus, and the relative contrast of the components (Serrano-Pedraza, Goddard, & Derrington, 2007; Serrano-Pedraza & Derrington, 2010). In this research we wanted to study the effect of speed or temporal frequency on the interaction between motion sensors. We performed three experiments where we measured duration thresholds in a motion direction discrimination task, and we also measured the proportion of correct responses. The stimuli used in the experiments were horizontally drifting vertical Gabor patches of 4° diameter (2σxy). In the first two experiments, five stimulus configurations of moving (m) and static (s) components were used: two simple stimuli, 1m c/° and 3m c/°; and three complex stimuli, 1m + 3m, 1m + 3s, and 1s + 3m. Results show that for all conditions but 1s + 3m, duration thresholds decrease (proportion of correct responses increase) with increasing speed. However, in condition 1s + 3m, duration thresholds increase from 0.5°/s to 2°/s and then decrease with increasing speed. In the third experiment we tested whether the interaction between scales is tuned to speed or temporal frequency using different conditions: 1s + 4m, 1s + 6m, 0.5s + 1.5m, and 2s + 6m. Results from duration thresholds suggest that the strength of the inhibitory interaction between motion sensors tuned to coarse and fine scales is temporal frequency tuned with a maximum around 6 Hz and a minimum between 6 and 12 Hz in the case of the proportion of correct responses.},
keywords = {DATAPixx},
pubstate = {published},
tppubtype = {article}
}
The perceived direction of motion of a brief moving fine scale pattern reverses when a static coarse scale pattern is added to it (Henning & Derrington, 1988). This impairment in motion direction discrimination has been explained by the inhibitory interaction between motion sensors tuned to fine and coarse scales. This interaction depends on the particular spatial frequencies mixed, the size of the stimulus, and the relative contrast of the components (Serrano-Pedraza, Goddard, & Derrington, 2007; Serrano-Pedraza & Derrington, 2010). In this research we wanted to study the effect of speed or temporal frequency on the interaction between motion sensors. We performed three experiments where we measured duration thresholds in a motion direction discrimination task, and we also measured the proportion of correct responses. The stimuli used in the experiments were horizontally drifting vertical Gabor patches of 4° diameter (2σxy). In the first two experiments, five stimulus configurations of moving (m) and static (s) components were used: two simple stimuli, 1m c/° and 3m c/°; and three complex stimuli, 1m + 3m, 1m + 3s, and 1s + 3m. Results show that for all conditions but 1s + 3m, duration thresholds decrease (proportion of correct responses increase) with increasing speed. However, in condition 1s + 3m, duration thresholds increase from 0.5°/s to 2°/s and then decrease with increasing speed. In the third experiment we tested whether the interaction between scales is tuned to speed or temporal frequency using different conditions: 1s + 4m, 1s + 6m, 0.5s + 1.5m, and 2s + 6m. Results from duration thresholds suggest that the strength of the inhibitory interaction between motion sensors tuned to coarse and fine scales is temporal frequency tuned with a maximum around 6 Hz and a minimum between 6 and 12 Hz in the case of the proportion of correct responses.
9.
Levi, Aaron J.; Yates, Jacob L.; Huk, Alexander C.; Katz, Leor N.
Strategic and Dynamic Temporal Weighting for Perceptual Decisions in Humans and Macaques Journal Article
In: eNeuro, vol. 5, no. 5, 2018, ISSN: 2373-2822, (Publisher: Society for Neuroscience Section: New Research).
Abstract | Links | BibTeX | Tags: DATAPixx
@article{levi_strategic_2018,
title = {Strategic and Dynamic Temporal Weighting for Perceptual Decisions in Humans and Macaques},
author = {Aaron J. Levi and Jacob L. Yates and Alexander C. Huk and Leor N. Katz},
url = {https://www.eneuro.org/content/5/5/ENEURO.0169-18.2018},
doi = {10.1523/ENEURO.0169-18.2018},
issn = {2373-2822},
year = {2018},
date = {2018-09-01},
urldate = {2024-01-18},
journal = {eNeuro},
volume = {5},
number = {5},
abstract = {Perceptual decision-making is often modeled as the accumulation of sensory evidence over time. Recent studies using psychophysical reverse correlation have shown that even though the sensory evidence is stationary over time, subjects may exhibit a time-varying weighting strategy, weighting some stimulus epochs more heavily than others. While previous work has explained time-varying weighting as a consequence of static decision mechanisms (e.g., decision bound or leak), here we show that time-varying weighting can reflect strategic adaptation to stimulus statistics, and thus can readily take a number of forms. We characterized the temporal weighting strategies of humans and macaques performing a motion discrimination task in which the amount of information carried by the motion stimulus was manipulated over time. Both species could adapt their temporal weighting strategy to match the time-varying statistics of the sensory stimulus. When early stimulus epochs had higher mean motion strength than late, subjects adopted a pronounced early weighting strategy, where early information was weighted more heavily in guiding perceptual decisions. When the mean motion strength was greater in later stimulus epochs, in contrast, subjects shifted to a marked late weighting strategy. These results demonstrate that perceptual decisions involve a temporally flexible weighting process in both humans and monkeys, and introduce a paradigm with which to manipulate sensory weighting in decision-making tasks.},
note = {Publisher: Society for Neuroscience
Section: New Research},
keywords = {DATAPixx},
pubstate = {published},
tppubtype = {article}
}
Perceptual decision-making is often modeled as the accumulation of sensory evidence over time. Recent studies using psychophysical reverse correlation have shown that even though the sensory evidence is stationary over time, subjects may exhibit a time-varying weighting strategy, weighting some stimulus epochs more heavily than others. While previous work has explained time-varying weighting as a consequence of static decision mechanisms (e.g., decision bound or leak), here we show that time-varying weighting can reflect strategic adaptation to stimulus statistics, and thus can readily take a number of forms. We characterized the temporal weighting strategies of humans and macaques performing a motion discrimination task in which the amount of information carried by the motion stimulus was manipulated over time. Both species could adapt their temporal weighting strategy to match the time-varying statistics of the sensory stimulus. When early stimulus epochs had higher mean motion strength than late, subjects adopted a pronounced early weighting strategy, where early information was weighted more heavily in guiding perceptual decisions. When the mean motion strength was greater in later stimulus epochs, in contrast, subjects shifted to a marked late weighting strategy. These results demonstrate that perceptual decisions involve a temporally flexible weighting process in both humans and monkeys, and introduce a paradigm with which to manipulate sensory weighting in decision-making tasks.
10.
Arranz-Paraíso, Sandra; Serrano-Pedraza, Ignacio
Testing the link between visual suppression and intelligence Journal Article
In: PLOS ONE, vol. 13, no. 7, pp. e0200151, 2018, ISSN: 1932-6203, (Publisher: Public Library of Science).
Abstract | Links | BibTeX | Tags: DATAPixx, RESPONSEPixx
@article{arranz-paraiso_testing_2018,
title = {Testing the link between visual suppression and intelligence},
author = {Sandra Arranz-Paraíso and Ignacio Serrano-Pedraza},
url = {https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0200151},
doi = {10.1371/journal.pone.0200151},
issn = {1932-6203},
year = {2018},
date = {2018-07-01},
urldate = {2023-12-21},
journal = {PLOS ONE},
volume = {13},
number = {7},
pages = {e0200151},
abstract = {The impairment to discriminate the motion direction of a large high contrast stimulus or to detect a stimulus surrounded by another one is called visual suppression and is the result of the normal function of our visual inhibitory mechanisms. Recently, Melnick et al. (2013), using a motion discrimination task, showed that intelligence strongly correlates with visual suppression (r = 0.71). Cook et al. (2016) also showed a strong link between contrast surround suppression and IQ (r = 0.87), this time using a contrast matching task. Our aim is to test this link using two different visual suppression tasks: a motion discrimination task and a contrast detection task. Fifty volunteers took part in the experiments. Using Bayesian staircases, we measured duration thresholds in the motion experiment and contrast thresholds in the spatial experiment. Although we found a much weaker effect, our results from the motion experiment still replicate previous results supporting the link between motion surround suppression and IQ (r = 0.43). However, our results from the spatial experiment do not support the link between contrast surround suppression and IQ (r = -0.09). Methodological differences between this study and previous studies which could explain these discrepancies are discussed.},
note = {Publisher: Public Library of Science},
keywords = {DATAPixx, RESPONSEPixx},
pubstate = {published},
tppubtype = {article}
}
The impairment to discriminate the motion direction of a large high contrast stimulus or to detect a stimulus surrounded by another one is called visual suppression and is the result of the normal function of our visual inhibitory mechanisms. Recently, Melnick et al. (2013), using a motion discrimination task, showed that intelligence strongly correlates with visual suppression (r = 0.71). Cook et al. (2016) also showed a strong link between contrast surround suppression and IQ (r = 0.87), this time using a contrast matching task. Our aim is to test this link using two different visual suppression tasks: a motion discrimination task and a contrast detection task. Fifty volunteers took part in the experiments. Using Bayesian staircases, we measured duration thresholds in the motion experiment and contrast thresholds in the spatial experiment. Although we found a much weaker effect, our results from the motion experiment still replicate previous results supporting the link between motion surround suppression and IQ (r = 0.43). However, our results from the spatial experiment do not support the link between contrast surround suppression and IQ (r = -0.09). Methodological differences between this study and previous studies which could explain these discrepancies are discussed.
11.
Tarawneh, Ghaith; Nityananda, Vivek; Rosner, Ronny; Errington, Steven; Herbert, William; Arranz-Paraíso, Sandra; Busby, Natalie; Tampin, Jimmy; Read, Jenny; Serrano-Pedraza, Ignacio
Contrast thresholds reveal different visual masking functions in humans and praying mantises Journal Article
In: Biology Open, vol. 7, no. 4, pp. bio029439, 2018, ISSN: 2046-6390.
Abstract | Links | BibTeX | Tags: DATAPixx, RESPONSEPixx
@article{tarawneh_contrast_2018,
title = {Contrast thresholds reveal different visual masking functions in humans and praying mantises},
author = {Ghaith Tarawneh and Vivek Nityananda and Ronny Rosner and Steven Errington and William Herbert and Sandra Arranz-Paraíso and Natalie Busby and Jimmy Tampin and Jenny Read and Ignacio Serrano-Pedraza},
url = {https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5936055/},
doi = {10.1242/bio.029439},
issn = {2046-6390},
year = {2018},
date = {2018-04-01},
urldate = {2024-01-02},
journal = {Biology Open},
volume = {7},
number = {4},
pages = {bio029439},
abstract = {Recently, we showed a novel property of the Hassenstein–Reichardt detector, namely that insect motion detection can be masked by ‘undetectable’ noise, i.e. visual noise presented at spatial frequencies at which coherently moving gratings do not elicit a response (). That study compared the responses of human and insect motion detectors using different ways of quantifying masking (contrast threshold in humans and masking tuning function in insects). In addition, some adjustments in experimental procedure, such as presenting the stimulus at a short viewing distance, were necessary to elicit a response in insects. These differences offer alternative explanations for the observed difference between human and insect responses to visual motion noise. Here, we report the results of new masking experiments in which we test whether differences in experimental paradigm and stimulus presentation between humans and insects can account for the undetectable noise effect reported earlier. We obtained contrast thresholds at two signal and two noise frequencies in both humans and praying mantises (Sphodromantis lineola), and compared contrast threshold differences when noise has the same versus different spatial frequency as the signal. Furthermore, we investigated whether differences in viewing geometry had any qualitative impact on the results. Consistent with our earlier finding, differences in contrast threshold show that visual noise masks much more effectively when presented at signal spatial frequency in humans (compared to a lower or higher spatial frequency), while in insects, noise is roughly equivalently effective when presented at either the signal spatial frequency or lower (compared to a higher spatial frequency). The characteristic difference between human and insect responses was unaffected by correcting for the stimulus distortion caused by short viewing distances in insects. These findings constitute stronger evidence that the undetectable noise effect reported earlier is a genuine difference between human and insect motion processing, and not an artefact caused by differences in experimental paradigms., Summary: We investigate alternative explanations for a reported difference between human and insect responses to masked moving gratings, and demonstrate that it is a genuine feature of their visual systems.},
keywords = {DATAPixx, RESPONSEPixx},
pubstate = {published},
tppubtype = {article}
}
Recently, we showed a novel property of the Hassenstein–Reichardt detector, namely that insect motion detection can be masked by ‘undetectable’ noise, i.e. visual noise presented at spatial frequencies at which coherently moving gratings do not elicit a response (). That study compared the responses of human and insect motion detectors using different ways of quantifying masking (contrast threshold in humans and masking tuning function in insects). In addition, some adjustments in experimental procedure, such as presenting the stimulus at a short viewing distance, were necessary to elicit a response in insects. These differences offer alternative explanations for the observed difference between human and insect responses to visual motion noise. Here, we report the results of new masking experiments in which we test whether differences in experimental paradigm and stimulus presentation between humans and insects can account for the undetectable noise effect reported earlier. We obtained contrast thresholds at two signal and two noise frequencies in both humans and praying mantises (Sphodromantis lineola), and compared contrast threshold differences when noise has the same versus different spatial frequency as the signal. Furthermore, we investigated whether differences in viewing geometry had any qualitative impact on the results. Consistent with our earlier finding, differences in contrast threshold show that visual noise masks much more effectively when presented at signal spatial frequency in humans (compared to a lower or higher spatial frequency), while in insects, noise is roughly equivalently effective when presented at either the signal spatial frequency or lower (compared to a higher spatial frequency). The characteristic difference between human and insect responses was unaffected by correcting for the stimulus distortion caused by short viewing distances in insects. These findings constitute stronger evidence that the undetectable noise effect reported earlier is a genuine difference between human and insect motion processing, and not an artefact caused by differences in experimental paradigms., Summary: We investigate alternative explanations for a reported difference between human and insect responses to masked moving gratings, and demonstrate that it is a genuine feature of their visual systems.
12.
Han, Shui'Er; Alais, David
Strength of continuous flash suppression is optimal when target and masker modulation rates are matched Journal Article
In: Journal of Vision, vol. 18, no. 3, pp. 3, 2018, ISSN: 1534-7362.
Abstract | Links | BibTeX | Tags: DATAPixx
@article{han_strength_2018,
title = {Strength of continuous flash suppression is optimal when target and masker modulation rates are matched},
author = {Shui'Er Han and David Alais},
url = {https://doi.org/10.1167/18.3.3},
doi = {10.1167/18.3.3},
issn = {1534-7362},
year = {2018},
date = {2018-03-01},
urldate = {2024-01-18},
journal = {Journal of Vision},
volume = {18},
number = {3},
pages = {3},
abstract = {Continuous flash suppression (CFS) is a popular technique whereby a dynamic sequence of Mondrian patterns is presented to one eye in order to suppress a static target presented to the other eye. Although the effectiveness of CFS is generally assumed to increase with the flicker rate of the Mondrian masker, a recent study has shown that suppression is optimal at very low masker rates for sustained targets, but higher rates may be necessary for transient targets. Here we vary the modulation rates of the masker and target using temporally filtered dynamic noise, which allowed us to examine the relationship between target and masker frequency and its effect on suppression strength. Using these carefully controlled, temporally narrowband stimuli, we demonstrate a pattern of results showing that suppression is greatest when target and masker modulate at similar frequencies. This finding indicates the involvement of early temporal-frequency-tuned filters underlying CFS and is consistent with many existing findings in the CFS literature. We also find that these temporally selective processes are orientation selective, which points to an early cortical substrate such as neurons in primary visual cortex. Overall, our study reveals that CFS suppression can be maximized by carefully matching the masker and target in temporal frequency and orientation. More generally, we show the importance of using carefully controlled stimuli for elucidating the underlying mechanisms of CFS. This approach is important at a theoretical level, as it will enable comparison of CFS with existing models of binocular rivalry and interocular suppression and facilitate a unified explanatory framework.},
keywords = {DATAPixx},
pubstate = {published},
tppubtype = {article}
}
Continuous flash suppression (CFS) is a popular technique whereby a dynamic sequence of Mondrian patterns is presented to one eye in order to suppress a static target presented to the other eye. Although the effectiveness of CFS is generally assumed to increase with the flicker rate of the Mondrian masker, a recent study has shown that suppression is optimal at very low masker rates for sustained targets, but higher rates may be necessary for transient targets. Here we vary the modulation rates of the masker and target using temporally filtered dynamic noise, which allowed us to examine the relationship between target and masker frequency and its effect on suppression strength. Using these carefully controlled, temporally narrowband stimuli, we demonstrate a pattern of results showing that suppression is greatest when target and masker modulate at similar frequencies. This finding indicates the involvement of early temporal-frequency-tuned filters underlying CFS and is consistent with many existing findings in the CFS literature. We also find that these temporally selective processes are orientation selective, which points to an early cortical substrate such as neurons in primary visual cortex. Overall, our study reveals that CFS suppression can be maximized by carefully matching the masker and target in temporal frequency and orientation. More generally, we show the importance of using carefully controlled stimuli for elucidating the underlying mechanisms of CFS. This approach is important at a theoretical level, as it will enable comparison of CFS with existing models of binocular rivalry and interocular suppression and facilitate a unified explanatory framework.
13.
Asher, Jordi M.; O’Hare, Louise; Romei, Vincenzo; Hibbard, Paul B.
Typical Lateral Interactions, but Increased Contrast Sensitivity, in Migraine-With-Aura Journal Article
In: Vision, vol. 2, no. 1, pp. 7, 2018, ISSN: 2411-5150, (Number: 1 Publisher: Multidisciplinary Digital Publishing Institute).
Abstract | Links | BibTeX | Tags: DATAPixx
@article{asher_typical_2018,
title = {Typical Lateral Interactions, but Increased Contrast Sensitivity, in Migraine-With-Aura},
author = {Jordi M. Asher and Louise O’Hare and Vincenzo Romei and Paul B. Hibbard},
url = {https://www.mdpi.com/2411-5150/2/1/7},
doi = {10.3390/vision2010007},
issn = {2411-5150},
year = {2018},
date = {2018-03-01},
urldate = {2024-01-18},
journal = {Vision},
volume = {2},
number = {1},
pages = {7},
abstract = {Individuals with migraine show differences in visual perception compared to control groups. It has been suggested that differences in lateral interactions between neurons might account for some of these differences. This study seeks to further establish the strength and spatial extent of excitatory and inhibitory interactions in migraine-with-aura using a classic lateral masking task. Observers indicated which of two intervals contained a centrally presented, vertical Gabor target of varying contrast. In separate blocks of trials, the target was presented alone or was flanked by two additional collinear, high contrast Gabors. Flanker distances varied between 1 and 12 wavelengths of the Gabor stimuli. Overall, contrast thresholds for the migraine group were lower than those in the control group. There was no difference in the degree of lateral interaction in the migraine group. These results are consistent with the previous work showing enhanced contrast sensitivity in migraine-with-aura for small, rapidly presented targets, and they suggest that impaired performance in global perceptual tasks in migraine may be attributed to difficulties in segmenting relevant from irrelevant features, rather than altered local mechanisms.},
note = {Number: 1
Publisher: Multidisciplinary Digital Publishing Institute},
keywords = {DATAPixx},
pubstate = {published},
tppubtype = {article}
}
Individuals with migraine show differences in visual perception compared to control groups. It has been suggested that differences in lateral interactions between neurons might account for some of these differences. This study seeks to further establish the strength and spatial extent of excitatory and inhibitory interactions in migraine-with-aura using a classic lateral masking task. Observers indicated which of two intervals contained a centrally presented, vertical Gabor target of varying contrast. In separate blocks of trials, the target was presented alone or was flanked by two additional collinear, high contrast Gabors. Flanker distances varied between 1 and 12 wavelengths of the Gabor stimuli. Overall, contrast thresholds for the migraine group were lower than those in the control group. There was no difference in the degree of lateral interaction in the migraine group. These results are consistent with the previous work showing enhanced contrast sensitivity in migraine-with-aura for small, rapidly presented targets, and they suggest that impaired performance in global perceptual tasks in migraine may be attributed to difficulties in segmenting relevant from irrelevant features, rather than altered local mechanisms.
14.
Han, Shui'er; Blake, Randolph; Alais, David
Slow and steady, not fast and furious: Slow temporal modulation strengthens continuous flash suppression Journal Article
In: Consciousness and Cognition, vol. 58, pp. 10–19, 2018, ISSN: 1053-8100.
Abstract | Links | BibTeX | Tags: DATAPixx
@article{han_slow_2018,
title = {Slow and steady, not fast and furious: Slow temporal modulation strengthens continuous flash suppression},
author = {Shui'er Han and Randolph Blake and David Alais},
url = {https://www.sciencedirect.com/science/article/pii/S1053810017304415},
doi = {10.1016/j.concog.2017.12.007},
issn = {1053-8100},
year = {2018},
date = {2018-02-01},
urldate = {2024-01-17},
journal = {Consciousness and Cognition},
volume = {58},
pages = {10–19},
abstract = {Continuous flash suppression (CFS) involves the presentation of a rapidly changing Mondrian sequence to one eye and a static target in the other eye. Targets presented in this manner remain suppressed for several seconds at a time, and this has seen the prevalent use of CFS in studies of unconscious visual processes. However, the mechanisms behind CFS remain unclear, complicating its use and the comprehension of results obtained with the paradigm. For example, some studies report observations indicative of faster, visual masking processes whereas others suggest slower, rivalry processes. To reconcile this discrepancy, this study investigates the effect of temporal frequency content and Mondrian pattern structure on CFS suppression. Our results show predominant influences of spatial edges and low temporal-frequency content, which are similar to binocular rivalry, affording a parsimonious alternative in unifying the two paradigms.},
keywords = {DATAPixx},
pubstate = {published},
tppubtype = {article}
}
Continuous flash suppression (CFS) involves the presentation of a rapidly changing Mondrian sequence to one eye and a static target in the other eye. Targets presented in this manner remain suppressed for several seconds at a time, and this has seen the prevalent use of CFS in studies of unconscious visual processes. However, the mechanisms behind CFS remain unclear, complicating its use and the comprehension of results obtained with the paradigm. For example, some studies report observations indicative of faster, visual masking processes whereas others suggest slower, rivalry processes. To reconcile this discrepancy, this study investigates the effect of temporal frequency content and Mondrian pattern structure on CFS suppression. Our results show predominant influences of spatial edges and low temporal-frequency content, which are similar to binocular rivalry, affording a parsimonious alternative in unifying the two paradigms.
15.
Alexander, Bonnie; Laycock, Robin; Crewther, David P.; Crewther, Sheila G.
An fMRI-Neuronavigated Chronometric TMS Investigation of V5 and Intraparietal Cortex in Motion Driven Attention Journal Article
In: Frontiers in Human Neuroscience, vol. 11, pp. 638, 2018, ISSN: 1662-5161.
Abstract | Links | BibTeX | Tags: DATAPixx, RESPONSEPixx, VPixxProgram
@article{alexander_fmri-neuronavigated_2018,
title = {An fMRI-Neuronavigated Chronometric TMS Investigation of V5 and Intraparietal Cortex in Motion Driven Attention},
author = {Bonnie Alexander and Robin Laycock and David P. Crewther and Sheila G. Crewther},
url = {https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5758491/},
doi = {10.3389/fnhum.2017.00638},
issn = {1662-5161},
year = {2018},
date = {2018-01-01},
urldate = {2023-12-21},
journal = {Frontiers in Human Neuroscience},
volume = {11},
pages = {638},
abstract = {The timing of networked brain activity subserving motion driven attention in humans is currently unclear. Functional MRI (fMRI)-neuronavigated chronometric transcranial magnetic stimulation (TMS) was used to investigate critical times of parietal cortex involvement in motion driven attention. In particular, we were interested in the relative critical times for two intraparietal sulcus (IPS) sites in comparison to that previously identified for motion processing in area V5, and to explore potential earlier times of involvement. fMRI was used to individually localize V5 and middle and posterior intraparietal sulcus (mIPS; pIPS) areas active for a motion driven attention task, prior to TMS neuronavigation. Paired-pulse TMS was applied during performance of the same task at stimulus onset asynchronies (SOAs) ranging from 0 to 180 ms. There were no statistically significant decreases in performance accuracy for trials where TMS was applied to V5 at any SOA, though stimulation intensity was lower for this site than for the parietal sites. For TMS applied to mIPS, there was a trend toward a relative decrease in performance accuracy at the 150 ms SOA, as well as a relative increase at 180 ms. There was no statistically significant effect overall of TMS applied to pIPS, however, there appeared a potential trend toward a decrease in performance at the 0 ms SOA. Overall, these results provide some patterns of potential theoretical interest to follow up in future studies.},
keywords = {DATAPixx, RESPONSEPixx, VPixxProgram},
pubstate = {published},
tppubtype = {article}
}
The timing of networked brain activity subserving motion driven attention in humans is currently unclear. Functional MRI (fMRI)-neuronavigated chronometric transcranial magnetic stimulation (TMS) was used to investigate critical times of parietal cortex involvement in motion driven attention. In particular, we were interested in the relative critical times for two intraparietal sulcus (IPS) sites in comparison to that previously identified for motion processing in area V5, and to explore potential earlier times of involvement. fMRI was used to individually localize V5 and middle and posterior intraparietal sulcus (mIPS; pIPS) areas active for a motion driven attention task, prior to TMS neuronavigation. Paired-pulse TMS was applied during performance of the same task at stimulus onset asynchronies (SOAs) ranging from 0 to 180 ms. There were no statistically significant decreases in performance accuracy for trials where TMS was applied to V5 at any SOA, though stimulation intensity was lower for this site than for the parietal sites. For TMS applied to mIPS, there was a trend toward a relative decrease in performance accuracy at the 150 ms SOA, as well as a relative increase at 180 ms. There was no statistically significant effect overall of TMS applied to pIPS, however, there appeared a potential trend toward a decrease in performance at the 0 ms SOA. Overall, these results provide some patterns of potential theoretical interest to follow up in future studies.
16.
Brown, Alyse; Corner, Molly; Crewther, David P.; Crewther, Sheila G.
Human Flicker Fusion Correlates With Physiological Measures of Magnocellular Neural Efficiency Journal Article
In: Frontiers in Human Neuroscience, vol. 12, 2018, ISSN: 1662-5161.
Abstract | Links | BibTeX | Tags: DATAPixx, VPixxProgram
@article{brown_human_2018,
title = {Human Flicker Fusion Correlates With Physiological Measures of Magnocellular Neural Efficiency},
author = {Alyse Brown and Molly Corner and David P. Crewther and Sheila G. Crewther},
url = {https://www.frontiersin.org/articles/10.3389/fnhum.2018.00176},
issn = {1662-5161},
year = {2018},
date = {2018-01-01},
urldate = {2023-12-21},
journal = {Frontiers in Human Neuroscience},
volume = {12},
abstract = {The rapidity with which the visual system can recover from stimulation in order to respond again has important implications for efficiently processing environmental stimuli in real time. To date, there has been little integration of the human psychophysical and physiological research underlying the neural mechanisms contributing to temporal limits on human visual perception. Hence, we investigated the relationship between achromatic flicker fusion frequency and temporal analysis of the magnocellular (M) and parvocellular (P) contributions to the achromatic non-linear multifocal Visual Evoked Potential (mfVEP) responses recorded from occipital scalp (Oz). It was hypothesized, on the basis of higher temporal cut-off frequencies reported for primate M vs. P neurons, that sinusoidal flicker fusion frequencies would negatively correlate with the amplitude of M- but not P-generated non-linearities of the mfVEP. This hypothesis was borne out in 72 typically developing young adults using a four-way forced choice sinusoidal flicker fusion task: amplitudes of all non-linearities that demonstrated a clear M-generated component correlated negatively with flicker thresholds. The strongest of these correlations were demonstrated by the main M non-linearity component (K2.1N70−P100) for both high contrast (r = −0.415},
keywords = {DATAPixx, VPixxProgram},
pubstate = {published},
tppubtype = {article}
}
The rapidity with which the visual system can recover from stimulation in order to respond again has important implications for efficiently processing environmental stimuli in real time. To date, there has been little integration of the human psychophysical and physiological research underlying the neural mechanisms contributing to temporal limits on human visual perception. Hence, we investigated the relationship between achromatic flicker fusion frequency and temporal analysis of the magnocellular (M) and parvocellular (P) contributions to the achromatic non-linear multifocal Visual Evoked Potential (mfVEP) responses recorded from occipital scalp (Oz). It was hypothesized, on the basis of higher temporal cut-off frequencies reported for primate M vs. P neurons, that sinusoidal flicker fusion frequencies would negatively correlate with the amplitude of M- but not P-generated non-linearities of the mfVEP. This hypothesis was borne out in 72 typically developing young adults using a four-way forced choice sinusoidal flicker fusion task: amplitudes of all non-linearities that demonstrated a clear M-generated component correlated negatively with flicker thresholds. The strongest of these correlations were demonstrated by the main M non-linearity component (K2.1N70−P100) for both high contrast (r = −0.415
17.
Smith, Danielle; Ropar, Danielle; Allen, Harriet A.
The Integration of Occlusion and Disparity Information for Judging Depth in Autism Spectrum Disorder Journal Article
In: Journal of Autism and Developmental Disorders, vol. 47, no. 10, pp. 3112–3124, 2017, ISSN: 1573-3432.
Abstract | Links | BibTeX | Tags: 3DPixx, DATAPixx
@article{smith_integration_2017,
title = {The Integration of Occlusion and Disparity Information for Judging Depth in Autism Spectrum Disorder},
author = {Danielle Smith and Danielle Ropar and Harriet A. Allen},
url = {https://doi.org/10.1007/s10803-017-3234-x},
doi = {10.1007/s10803-017-3234-x},
issn = {1573-3432},
year = {2017},
date = {2017-10-01},
urldate = {2024-01-18},
journal = {Journal of Autism and Developmental Disorders},
volume = {47},
number = {10},
pages = {3112–3124},
abstract = {In autism spectrum disorder (ASD), atypical integration of visual depth cues may be due to flattened perceptual priors or selective fusion. The current study attempts to disentangle these explanations by psychophysically assessing within-modality integration of ordinal (occlusion) and metric (disparity) depth cues while accounting for sensitivity to stereoscopic information. Participants included 22 individuals with ASD and 23 typically developing matched controls. Although adults with ASD were found to have significantly poorer stereoacuity, they were still able to automatically integrate conflicting depth cues, lending support to the idea that priors are intact in ASD. However, dissimilarities in response speed variability between the ASD and TD groups suggests that there may be differences in the perceptual decision-making aspect of the task.},
keywords = {3DPixx, DATAPixx},
pubstate = {published},
tppubtype = {article}
}
In autism spectrum disorder (ASD), atypical integration of visual depth cues may be due to flattened perceptual priors or selective fusion. The current study attempts to disentangle these explanations by psychophysically assessing within-modality integration of ordinal (occlusion) and metric (disparity) depth cues while accounting for sensitivity to stereoscopic information. Participants included 22 individuals with ASD and 23 typically developing matched controls. Although adults with ASD were found to have significantly poorer stereoacuity, they were still able to automatically integrate conflicting depth cues, lending support to the idea that priors are intact in ASD. However, dissimilarities in response speed variability between the ASD and TD groups suggests that there may be differences in the perceptual decision-making aspect of the task.
18.
Yates, Jacob L.; Park, Il Memming; Katz, Leor N.; Pillow, Jonathan W.; Huk, Alexander C.
Functional dissection of signal and noise in MT and LIP during decision-making Journal Article
In: Nature neuroscience, vol. 20, no. 9, pp. 1285–1292, 2017, ISSN: 1097-6256.
Abstract | Links | BibTeX | Tags: DATAPixx
@article{yates_functional_2017,
title = {Functional dissection of signal and noise in MT and LIP during decision-making},
author = {Jacob L. Yates and Il Memming Park and Leor N. Katz and Jonathan W. Pillow and Alexander C. Huk},
url = {https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5673485/},
doi = {10.1038/nn.4611},
issn = {1097-6256},
year = {2017},
date = {2017-09-01},
urldate = {2024-01-03},
journal = {Nature neuroscience},
volume = {20},
number = {9},
pages = {1285–1292},
abstract = {During perceptual decision making, responses in the middle temporal (MT) and lateral intraparietal (LIP) areas appear to map onto theoretically defined quantities, with MT representing instantaneous motion evidence and LIP reflecting the accumulated evidence. However, several aspects of the transformation between the two areas have not been empirically tested. We therefore performed multi-stage systems identification analyses of the simultaneous activity of MT and LIP during individual decisions. We found that monkeys based their choices on evidence presented in early epochs of the motion stimulus, and that substantial early weighting of motion was present in MT responses. LIP’s responses recapitulated MT’s early weighting and contained a choice-dependent buildup that was distinguishable from motion integration. Furthermore, trial-by-trial variability in LIP did not depend on MT activity. These results identify important deviations from the idealizations of MT and LIP and motivate inquiry into sensorimotor computations that may intervene between MT and LIP.},
keywords = {DATAPixx},
pubstate = {published},
tppubtype = {article}
}
During perceptual decision making, responses in the middle temporal (MT) and lateral intraparietal (LIP) areas appear to map onto theoretically defined quantities, with MT representing instantaneous motion evidence and LIP reflecting the accumulated evidence. However, several aspects of the transformation between the two areas have not been empirically tested. We therefore performed multi-stage systems identification analyses of the simultaneous activity of MT and LIP during individual decisions. We found that monkeys based their choices on evidence presented in early epochs of the motion stimulus, and that substantial early weighting of motion was present in MT responses. LIP’s responses recapitulated MT’s early weighting and contained a choice-dependent buildup that was distinguishable from motion integration. Furthermore, trial-by-trial variability in LIP did not depend on MT activity. These results identify important deviations from the idealizations of MT and LIP and motivate inquiry into sensorimotor computations that may intervene between MT and LIP.
19.
Alais, David; Ho, Tam; Han, Shui’er; der Burg, Erik Van
A Matched Comparison Across Three Different Sensory Pairs of Cross-Modal Temporal Recalibration From Sustained and Transient Adaptation Journal Article
In: i-Perception, vol. 8, no. 4, pp. 2041669517718697, 2017, ISSN: 2041-6695, (Publisher: SAGE Publications).
Abstract | Links | BibTeX | Tags: DATAPixx, VIEWPixx
@article{alais_matched_2017,
title = {A Matched Comparison Across Three Different Sensory Pairs of Cross-Modal Temporal Recalibration From Sustained and Transient Adaptation},
author = {David Alais and Tam Ho and Shui’er Han and Erik Van der Burg},
url = {https://doi.org/10.1177/2041669517718697},
doi = {10.1177/2041669517718697},
issn = {2041-6695},
year = {2017},
date = {2017-08-01},
urldate = {2023-12-21},
journal = {i-Perception},
volume = {8},
number = {4},
pages = {2041669517718697},
abstract = {Sustained exposure to an asynchronous multisensory signal causes perceived simultaneity to shift in the direction of the leading component of the adapting stimulus. This is known as temporal recalibration, and recent evidence suggests that it can occur very rapidly, even after a single asynchronous audiovisual (AV) stimulus. However, this form of rapid recalibration appears to be unique to AV stimuli, in contrast to recalibration following sustained asynchronies which occurs with audiotactile (AT) and visuotactile (VT) stimuli. This study examines temporal recalibration to AV, VT and AT asynchrony with spatially collocated stimuli using a design that produces both sustained and inter-trial recalibration by combining the traditional sustained adaptation approach with an inter-trial analysis of sequential dependencies in an extended test period. Thus, we compare temporal recalibration to both sustained and transient asynchrony in three crossmodal combinations using the same design, stimuli and observers. The results reveal that prolonged exposure to asynchrony produced equivalent temporal recalibration for all combinations: AV, AT and VT. The pattern for rapid, inter-trial recalibration was very different. Rapid recalibration occurred strongly for AV stimuli, weakly for AT and did not occur at all for VT. For all sensory pairings, recalibration from sustained asynchrony decayed to baseline during the test phase while inter-trial recalibration was present and stable throughout testing, suggesting different mechanisms may underlie adaptation at long and short timescales.},
note = {Publisher: SAGE Publications},
keywords = {DATAPixx, VIEWPixx},
pubstate = {published},
tppubtype = {article}
}
Sustained exposure to an asynchronous multisensory signal causes perceived simultaneity to shift in the direction of the leading component of the adapting stimulus. This is known as temporal recalibration, and recent evidence suggests that it can occur very rapidly, even after a single asynchronous audiovisual (AV) stimulus. However, this form of rapid recalibration appears to be unique to AV stimuli, in contrast to recalibration following sustained asynchronies which occurs with audiotactile (AT) and visuotactile (VT) stimuli. This study examines temporal recalibration to AV, VT and AT asynchrony with spatially collocated stimuli using a design that produces both sustained and inter-trial recalibration by combining the traditional sustained adaptation approach with an inter-trial analysis of sequential dependencies in an extended test period. Thus, we compare temporal recalibration to both sustained and transient asynchrony in three crossmodal combinations using the same design, stimuli and observers. The results reveal that prolonged exposure to asynchrony produced equivalent temporal recalibration for all combinations: AV, AT and VT. The pattern for rapid, inter-trial recalibration was very different. Rapid recalibration occurred strongly for AV stimuli, weakly for AT and did not occur at all for VT. For all sensory pairings, recalibration from sustained asynchrony decayed to baseline during the test phase while inter-trial recalibration was present and stable throughout testing, suggesting different mechanisms may underlie adaptation at long and short timescales.
20.
Hugrass, Laila; Slavikova, Jana; Horvat, Melissa; Musawi, Alaa Al; Crewther, David
Temporal brightness illusion changes color perception of “the dress” Journal Article
In: Journal of Vision, vol. 17, no. 5, pp. 6, 2017, ISSN: 1534-7362.
Abstract | Links | BibTeX | Tags: DATAPixx, RESPONSEPixx, VPixxProgram
@article{hugrass_temporal_2017,
title = {Temporal brightness illusion changes color perception of “the dress”},
author = {Laila Hugrass and Jana Slavikova and Melissa Horvat and Alaa Al Musawi and David Crewther},
url = {https://doi.org/10.1167/17.5.6},
doi = {10.1167/17.5.6},
issn = {1534-7362},
year = {2017},
date = {2017-06-01},
urldate = {2023-12-21},
journal = {Journal of Vision},
volume = {17},
number = {5},
pages = {6},
abstract = {“The dress” has provoked intensive commentary among psychophysicists, especially in relation to color vision. Researchers have shown that manipulating illuminance cues can influence the perceived colors of the dress. Here we investigate whether illusory shifts in brightness can shift color perception of the dress. Drifting achromatic gratings with fast off and fast on shading profiles are known to give an illusion of brightening or darkening, respectively. We superimposed rotating sawtooth gratings on a series of dress images that morphed from extreme white/gold through to blue/black. In a sample of 18 adults (11 with white/gold dress percept and seven with blue/black percept), a two-alternative, forced-choice constant stimulus task measured the morphed image point at which each observer was equally likely to categorize the dress as white/gold or blue/black (the point of subjective equality or PSE). Despite manifest individual differences in the PSE, the two sawtooth temporal profiles consistently changed the perceived colors of the dress. Perceptual dimming shifted color categorization toward blue/black whereas perceptual brightening shifted color categorization toward white/gold. We conclude that color categorization is influenced substantially by illusory shifts in brightness.},
keywords = {DATAPixx, RESPONSEPixx, VPixxProgram},
pubstate = {published},
tppubtype = {article}
}
“The dress” has provoked intensive commentary among psychophysicists, especially in relation to color vision. Researchers have shown that manipulating illuminance cues can influence the perceived colors of the dress. Here we investigate whether illusory shifts in brightness can shift color perception of the dress. Drifting achromatic gratings with fast off and fast on shading profiles are known to give an illusion of brightening or darkening, respectively. We superimposed rotating sawtooth gratings on a series of dress images that morphed from extreme white/gold through to blue/black. In a sample of 18 adults (11 with white/gold dress percept and seven with blue/black percept), a two-alternative, forced-choice constant stimulus task measured the morphed image point at which each observer was equally likely to categorize the dress as white/gold or blue/black (the point of subjective equality or PSE). Despite manifest individual differences in the PSE, the two sawtooth temporal profiles consistently changed the perceived colors of the dress. Perceptual dimming shifted color categorization toward blue/black whereas perceptual brightening shifted color categorization toward white/gold. We conclude that color categorization is influenced substantially by illusory shifts in brightness.