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.
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Use the search tool below to search for specific terms among the titles, authors and abstracts in our library.
201.
Laycock, Robin; Chan, Daniel; Crewther, Sheila G.
Attention Orienting in Response to Non-conscious Hierarchical Arrows: Individuals with Higher Autistic Traits Differ in Their Global/Local Bias Journal Article
In: Frontiers in Psychology, vol. 8, 2017, ISSN: 1664-1078.
Abstract | Links | BibTeX | Tags: RESPONSEPixx, VPixxProgram
@article{laycock_attention_2017,
title = {Attention Orienting in Response to Non-conscious Hierarchical Arrows: Individuals with Higher Autistic Traits Differ in Their Global/Local Bias},
author = {Robin Laycock and Daniel Chan and Sheila G. Crewther},
url = {https://www.frontiersin.org/articles/10.3389/fpsyg.2017.00023},
issn = {1664-1078},
year = {2017},
date = {2017-01-01},
urldate = {2023-12-21},
journal = {Frontiers in Psychology},
volume = {8},
abstract = {One aspect of the social communication impairments that characterize autism spectrum disorder (ASD) include reduced use of often subtle non-verbal social cues. People with ASD, and those with self-reported sub-threshold autistic traits, also show impairments in rapid visual processing of stimuli unrelated to social or emotional properties. Hence, this study sought to investigate whether perceptually non-conscious visual processing is related to autistic traits. A neurotypical sample of thirty young adults completed the Subthreshold Autism Trait Questionnaire and a Posner-like attention cueing task. Continuous Flash Suppression (CFS) was employed to render incongruous hierarchical arrow cues perceptually invisible prior to consciously presented targets. This was achieved via a 10 Hz masking stimulus presented to the dominant eye that suppressed information presented to the non-dominant eye. Non-conscious arrows consisted of local arrow elements pointing in one direction, and forming a global arrow shape pointing in the opposite direction. On each trial, the cue provided either a valid or invalid cue for the spatial location of the subsequent target, depending on which level (global or local) received privileged attention. A significant autism-trait group by global cue validity interaction indicated a difference in the extent of non-conscious local/global cueing between groups. Simple effect analyses revealed that whilst participants with lower autistic traits showed a global arrow cueing effect, those with higher autistic traits demonstrated a small local arrow cueing effect. These results suggest that non-conscious processing biases in local/global attention may be related to individual differences in autistic traits.},
keywords = {RESPONSEPixx, VPixxProgram},
pubstate = {published},
tppubtype = {article}
}
One aspect of the social communication impairments that characterize autism spectrum disorder (ASD) include reduced use of often subtle non-verbal social cues. People with ASD, and those with self-reported sub-threshold autistic traits, also show impairments in rapid visual processing of stimuli unrelated to social or emotional properties. Hence, this study sought to investigate whether perceptually non-conscious visual processing is related to autistic traits. A neurotypical sample of thirty young adults completed the Subthreshold Autism Trait Questionnaire and a Posner-like attention cueing task. Continuous Flash Suppression (CFS) was employed to render incongruous hierarchical arrow cues perceptually invisible prior to consciously presented targets. This was achieved via a 10 Hz masking stimulus presented to the dominant eye that suppressed information presented to the non-dominant eye. Non-conscious arrows consisted of local arrow elements pointing in one direction, and forming a global arrow shape pointing in the opposite direction. On each trial, the cue provided either a valid or invalid cue for the spatial location of the subsequent target, depending on which level (global or local) received privileged attention. A significant autism-trait group by global cue validity interaction indicated a difference in the extent of non-conscious local/global cueing between groups. Simple effect analyses revealed that whilst participants with lower autistic traits showed a global arrow cueing effect, those with higher autistic traits demonstrated a small local arrow cueing effect. These results suggest that non-conscious processing biases in local/global attention may be related to individual differences in autistic traits.
202.
Krigolson, Olave E.; Williams, Chad C.; Norton, Angela; Hassall, Cameron D.; Colino, Francisco L.
Choosing MUSE: Validation of a Low-Cost, Portable EEG System for ERP Research Journal Article
In: Frontiers in Neuroscience, vol. 11, 2017, ISSN: 1662-453X.
Abstract | Links | BibTeX | Tags: DATAPixx
@article{krigolson_choosing_2017,
title = {Choosing MUSE: Validation of a Low-Cost, Portable EEG System for ERP Research},
author = {Olave E. Krigolson and Chad C. Williams and Angela Norton and Cameron D. Hassall and Francisco L. Colino},
url = {https://www.frontiersin.org/articles/10.3389/fnins.2017.00109},
issn = {1662-453X},
year = {2017},
date = {2017-01-01},
urldate = {2023-12-22},
journal = {Frontiers in Neuroscience},
volume = {11},
abstract = {In recent years there has been an increase in the number of portable low-cost electroencephalographic (EEG) systems available to researchers. However, to date the validation of the use of low-cost EEG systems has focused on continuous recording of EEG data and/or the replication of large system EEG setups reliant on event-markers to afford examination of event-related brain potentials (ERP). Here, we demonstrate that it is possible to conduct ERP research without being reliant on event markers using a portable MUSE EEG system and a single computer. Specifically, we report the results of two experiments using data collected with the MUSE EEG system—one using the well-known visual oddball paradigm and the other using a standard reward-learning task. Our results demonstrate that we could observe and quantify the N200 and P300 ERP components in the visual oddball task and the reward positivity (the mirror opposite component to the feedback-related negativity) in the reward-learning task. Specifically, single sample t-tests of component existence (all p's < 0.05), computation of Bayesian credible intervals, and 95% confidence intervals all statistically verified the existence of the N200, P300, and reward positivity in all analyses. We provide with this research paper an open source website with all the instructions, methods, and software to replicate our findings and to provide researchers with an easy way to use the MUSE EEG system for ERP research. Importantly, our work highlights that with a single computer and a portable EEG system such as the MUSE one can conduct ERP research with ease thus greatly extending the possible use of the ERP methodology to a variety of novel contexts.},
keywords = {DATAPixx},
pubstate = {published},
tppubtype = {article}
}
In recent years there has been an increase in the number of portable low-cost electroencephalographic (EEG) systems available to researchers. However, to date the validation of the use of low-cost EEG systems has focused on continuous recording of EEG data and/or the replication of large system EEG setups reliant on event-markers to afford examination of event-related brain potentials (ERP). Here, we demonstrate that it is possible to conduct ERP research without being reliant on event markers using a portable MUSE EEG system and a single computer. Specifically, we report the results of two experiments using data collected with the MUSE EEG system—one using the well-known visual oddball paradigm and the other using a standard reward-learning task. Our results demonstrate that we could observe and quantify the N200 and P300 ERP components in the visual oddball task and the reward positivity (the mirror opposite component to the feedback-related negativity) in the reward-learning task. Specifically, single sample t-tests of component existence (all p's < 0.05), computation of Bayesian credible intervals, and 95% confidence intervals all statistically verified the existence of the N200, P300, and reward positivity in all analyses. We provide with this research paper an open source website with all the instructions, methods, and software to replicate our findings and to provide researchers with an easy way to use the MUSE EEG system for ERP research. Importantly, our work highlights that with a single computer and a portable EEG system such as the MUSE one can conduct ERP research with ease thus greatly extending the possible use of the ERP methodology to a variety of novel contexts.
203.
Allard, Rémy; Arleo, Angelo
Factorizing the motion sensitivity function into equivalent input noise and calculation efficiency Journal Article
In: Journal of Vision, vol. 17, no. 1, pp. 17, 2017, ISSN: 1534-7362.
Abstract | Links | BibTeX | Tags: VIEWPixx
@article{allard_factorizing_2017,
title = {Factorizing the motion sensitivity function into equivalent input noise and calculation efficiency},
author = {Rémy Allard and Angelo Arleo},
url = {https://doi.org/10.1167/17.1.17},
doi = {10.1167/17.1.17},
issn = {1534-7362},
year = {2017},
date = {2017-01-01},
urldate = {2024-01-03},
journal = {Journal of Vision},
volume = {17},
number = {1},
pages = {17},
abstract = {The photopic motion sensitivity function of the energy-based motion system is band-pass peaking around 8 Hz. Using an external noise paradigm to factorize the sensitivity into equivalent input noise and calculation efficiency, the present study investigated if the variation in photopic motion sensitivity as a function of the temporal frequency is due to a variation of equivalent input noise (e.g., early temporal filtering) or calculation efficiency (ability to select and integrate motion). For various temporal frequencies, contrast thresholds for a direction discrimination task were measured in presence and absence of noise. Up to 15 Hz, the sensitivity variation was mainly due to a variation of equivalent input noise and little variation in calculation efficiency was observed. The sensitivity fall-off at very high temporal frequencies (from 15 to 30 Hz) was due to a combination of a drop of calculation efficiency and a rise of equivalent input noise. A control experiment in which an artificial temporal integration was applied to the stimulus showed that an early temporal filter (generally assumed to affect equivalent input noise, not calculation efficiency) could impair both the calculation efficiency and equivalent input noise at very high temporal frequencies. We conclude that at the photopic luminance intensity tested, the variation of motion sensitivity as a function of the temporal frequency was mainly due to early temporal filtering, not to the ability to select and integrate motion. More specifically, we conclude that photopic motion sensitivity at high temporal frequencies is limited by internal noise occurring after the transduction process (i.e., neural noise), not by quantal noise resulting from the probabilistic absorption of photons by the photoreceptors as previously suggested.},
keywords = {VIEWPixx},
pubstate = {published},
tppubtype = {article}
}
The photopic motion sensitivity function of the energy-based motion system is band-pass peaking around 8 Hz. Using an external noise paradigm to factorize the sensitivity into equivalent input noise and calculation efficiency, the present study investigated if the variation in photopic motion sensitivity as a function of the temporal frequency is due to a variation of equivalent input noise (e.g., early temporal filtering) or calculation efficiency (ability to select and integrate motion). For various temporal frequencies, contrast thresholds for a direction discrimination task were measured in presence and absence of noise. Up to 15 Hz, the sensitivity variation was mainly due to a variation of equivalent input noise and little variation in calculation efficiency was observed. The sensitivity fall-off at very high temporal frequencies (from 15 to 30 Hz) was due to a combination of a drop of calculation efficiency and a rise of equivalent input noise. A control experiment in which an artificial temporal integration was applied to the stimulus showed that an early temporal filter (generally assumed to affect equivalent input noise, not calculation efficiency) could impair both the calculation efficiency and equivalent input noise at very high temporal frequencies. We conclude that at the photopic luminance intensity tested, the variation of motion sensitivity as a function of the temporal frequency was mainly due to early temporal filtering, not to the ability to select and integrate motion. More specifically, we conclude that photopic motion sensitivity at high temporal frequencies is limited by internal noise occurring after the transduction process (i.e., neural noise), not by quantal noise resulting from the probabilistic absorption of photons by the photoreceptors as previously suggested.
204.
Pitchaimuthu, Kabilan; Nguyen, Bao N.; McKendrick, Allison M.
Aging alters intraocular but not interocular foveal center surround contrast suppression Journal Article
In: Journal of Vision, vol. 17, no. 1, pp. 16, 2017, ISSN: 1534-7362.
Abstract | Links | BibTeX | Tags: VIEWPixx
@article{pitchaimuthu_aging_2017,
title = {Aging alters intraocular but not interocular foveal center surround contrast suppression},
author = {Kabilan Pitchaimuthu and Bao N. Nguyen and Allison M. McKendrick},
url = {https://doi.org/10.1167/17.1.16},
doi = {10.1167/17.1.16},
issn = {1534-7362},
year = {2017},
date = {2017-01-01},
urldate = {2024-01-03},
journal = {Journal of Vision},
volume = {17},
number = {1},
pages = {16},
abstract = {Numerous previous studies have shown that healthy aging results in increased foveal center surround contrast suppression when the center and surround patterns are presented to both eyes. The mechanistic cause of this observation is not well established. Neurophysiological and psychophysical studies have shown that different mechanisms of parafoveal center surround suppression can be tapped by manipulating viewing conditions to present the center and surround to the same eye (intraocular viewing) or to different eyes (interocular viewing), or by manipulating stimulus parameters such as duration. Here, we tested intraocular and interocular foveal center surround contrast suppression for stimuli of 40 ms and 200 ms duration in 18 younger and 18 older adults. For both groups, foveal intraocular center surround contrast suppression decreased with longer stimulus duration whereas interocular surround suppression did not, confirming contributions from separate mechanisms to these forms of suppression. Intraocular center surround contrast suppression was increased in older adults compared to younger adults; however, interocular suppression was similar in both groups. Our results indicate that aging differentially affects distinct forms of suppression arising at various levels of the visual pathway.},
keywords = {VIEWPixx},
pubstate = {published},
tppubtype = {article}
}
Numerous previous studies have shown that healthy aging results in increased foveal center surround contrast suppression when the center and surround patterns are presented to both eyes. The mechanistic cause of this observation is not well established. Neurophysiological and psychophysical studies have shown that different mechanisms of parafoveal center surround suppression can be tapped by manipulating viewing conditions to present the center and surround to the same eye (intraocular viewing) or to different eyes (interocular viewing), or by manipulating stimulus parameters such as duration. Here, we tested intraocular and interocular foveal center surround contrast suppression for stimuli of 40 ms and 200 ms duration in 18 younger and 18 older adults. For both groups, foveal intraocular center surround contrast suppression decreased with longer stimulus duration whereas interocular surround suppression did not, confirming contributions from separate mechanisms to these forms of suppression. Intraocular center surround contrast suppression was increased in older adults compared to younger adults; however, interocular suppression was similar in both groups. Our results indicate that aging differentially affects distinct forms of suppression arising at various levels of the visual pathway.
205.
Burt, Adelaide; Hugrass, Laila; Frith-Belvedere, Tash; Crewther, David
Insensitivity to Fearful Emotion for Early ERP Components in High Autistic Tendency Is Associated with Lower Magnocellular Efficiency Journal Article
In: Frontiers in Human Neuroscience, vol. 11, 2017, ISSN: 1662-5161.
Abstract | Links | BibTeX | Tags: RESPONSEPixx, VPixxProgram
@article{burt_insensitivity_2017,
title = {Insensitivity to Fearful Emotion for Early ERP Components in High Autistic Tendency Is Associated with Lower Magnocellular Efficiency},
author = {Adelaide Burt and Laila Hugrass and Tash Frith-Belvedere and David Crewther},
url = {https://www.frontiersin.org/articles/10.3389/fnhum.2017.00495},
issn = {1662-5161},
year = {2017},
date = {2017-01-01},
urldate = {2024-01-08},
journal = {Frontiers in Human Neuroscience},
volume = {11},
abstract = {Low spatial frequency (LSF) visual information is extracted rapidly from fearful faces, suggesting magnocellular involvement. Autistic phenotypes demonstrate altered magnocellular processing, which we propose contributes to a decreased P100 evoked response to LSF fearful faces. Here, we investigated whether rapid processing of fearful facial expressions differs for groups of neurotypical adults with low and high scores on the Autistic Spectrum Quotient (AQ). We created hybrid face stimuli with low and high spatial frequency filtered, fearful, and neutral expressions. Fearful faces produced higher amplitude P100 responses than neutral faces in the low AQ group, particularly when the hybrid face contained a LSF fearful expression. By contrast, there was no effect of fearful expression on P100 amplitude in the high AQ group. Consistent with evidence linking magnocellular differences with autistic personality traits, our non-linear VEP results showed that the high AQ group had higher amplitude K2.1 responses than the low AQ group, which is indicative of less efficient magnocellular recovery. Our results suggest that magnocellular LSF processing of a human face may be the initial visual cue used to rapidly and automatically detect fear, but that this cue functions atypically in those with high autistic tendency.},
keywords = {RESPONSEPixx, VPixxProgram},
pubstate = {published},
tppubtype = {article}
}
Low spatial frequency (LSF) visual information is extracted rapidly from fearful faces, suggesting magnocellular involvement. Autistic phenotypes demonstrate altered magnocellular processing, which we propose contributes to a decreased P100 evoked response to LSF fearful faces. Here, we investigated whether rapid processing of fearful facial expressions differs for groups of neurotypical adults with low and high scores on the Autistic Spectrum Quotient (AQ). We created hybrid face stimuli with low and high spatial frequency filtered, fearful, and neutral expressions. Fearful faces produced higher amplitude P100 responses than neutral faces in the low AQ group, particularly when the hybrid face contained a LSF fearful expression. By contrast, there was no effect of fearful expression on P100 amplitude in the high AQ group. Consistent with evidence linking magnocellular differences with autistic personality traits, our non-linear VEP results showed that the high AQ group had higher amplitude K2.1 responses than the low AQ group, which is indicative of less efficient magnocellular recovery. Our results suggest that magnocellular LSF processing of a human face may be the initial visual cue used to rapidly and automatically detect fear, but that this cue functions atypically in those with high autistic tendency.
206.
Wichmann, Felix A.; Janssen, David H. J.; Geirhos, Robert; Aguilar, Guillermo; Schütt, Heiko H.; Maertens, Marianne; Bethge, Matthias
Methods and measurements to compare men against machines Journal Article
In: Electronic Imaging, vol. 29, no. 14, pp. 36–45, 2017, ISSN: 2470-1173.
Abstract | Links | BibTeX | Tags: VIEWPixx
@article{wichmann_methods_2017,
title = {Methods and measurements to compare men against machines},
author = {Felix A. Wichmann and David H. J. Janssen and Robert Geirhos and Guillermo Aguilar and Heiko H. Schütt and Marianne Maertens and Matthias Bethge},
url = {https://library.imaging.org/ei/articles/29/14/art00004},
doi = {10.2352/ISSN.2470-1173.2017.14.HVEI-113},
issn = {2470-1173},
year = {2017},
date = {2017-01-01},
urldate = {2024-01-12},
journal = {Electronic Imaging},
volume = {29},
number = {14},
pages = {36–45},
abstract = {Recent advances in computational models in vision science have considerably furthered our understanding of human visual perception. At the same time, rapid advances in convolutional deep neural networks (DNNs) have resulted in computer vision models of object recognition which, for the first time, rival human object recognition. Furthermore, it has been suggested that DNNs may not only be successful models for computer vision, but may also be good computational models of the monkey and human visual systems. The advances in computational models in both vision science and computer vision pose two challenges in two different and independent domains: First, because the latest computational models have much higher predictive accuracy, and competing models may make similar predictions, we require more human data to be able to statistically distinguish between different models. Thus we would like to have methods to acquire trustworthy human behavioural data fast and easy. Second, we need challenging experiments to ascertain whether models show similar input-output behaviour only near “ceiling” performance, or whether their performance degrades similar to human performance: only then do we have strong evidence that models and human observers may be using similar features and processing strategies. In this paper we address both challenges.},
keywords = {VIEWPixx},
pubstate = {published},
tppubtype = {article}
}
Recent advances in computational models in vision science have considerably furthered our understanding of human visual perception. At the same time, rapid advances in convolutional deep neural networks (DNNs) have resulted in computer vision models of object recognition which, for the first time, rival human object recognition. Furthermore, it has been suggested that DNNs may not only be successful models for computer vision, but may also be good computational models of the monkey and human visual systems. The advances in computational models in both vision science and computer vision pose two challenges in two different and independent domains: First, because the latest computational models have much higher predictive accuracy, and competing models may make similar predictions, we require more human data to be able to statistically distinguish between different models. Thus we would like to have methods to acquire trustworthy human behavioural data fast and easy. Second, we need challenging experiments to ascertain whether models show similar input-output behaviour only near “ceiling” performance, or whether their performance degrades similar to human performance: only then do we have strong evidence that models and human observers may be using similar features and processing strategies. In this paper we address both challenges.
207.
Vancleef, Kathleen; Read, Jenny C. A.; Herbert, William; Goodship, Nicola; Woodhouse, Maeve; Serrano-Pedraza, Ignacio
Overestimation of stereo thresholds by the TNO stereotest is not due to global stereopsis Journal Article
In: Ophthalmic and Physiological Optics, vol. 37, no. 4, pp. 507–520, 2017, ISSN: 1475-1313, (_eprint: https://onlinelibrary.wiley.com/doi/pdf/10.1111/opo.12371).
Abstract | Links | BibTeX | Tags: RESPONSEPixx
@article{vancleef_overestimation_2017,
title = {Overestimation of stereo thresholds by the TNO stereotest is not due to global stereopsis},
author = {Kathleen Vancleef and Jenny C. A. Read and William Herbert and Nicola Goodship and Maeve Woodhouse and Ignacio Serrano-Pedraza},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/opo.12371},
doi = {10.1111/opo.12371},
issn = {1475-1313},
year = {2017},
date = {2017-01-01},
urldate = {2024-01-16},
journal = {Ophthalmic and Physiological Optics},
volume = {37},
number = {4},
pages = {507–520},
abstract = {Purpose It has been repeatedly shown that the TNO stereotest overestimates stereo threshold compared to other clinical stereotests. In the current study, we test whether this overestimation can be attributed to a distinction between ‘global’ (or ‘cyclopean’) and ‘local’ (feature or contour-based) stereopsis. Methods We compared stereo thresholds of a global (TNO) and a local clinical stereotest (Randot Circles). In addition, a global and a local psychophysical stereotest were added to the design. One hundred and forty-nine children between 4 and 16 years old were included in the study. Results Stereo threshold estimates with TNO were a factor of two higher than with any of the other stereotests. No significant differences were found between the other tests. Bland-Altman analyses also indicated low agreement between TNO and the other stereotests, especially for higher stereo threshold estimates. Simulations indicated that the TNO test protocol and test disparities can account for part of this effect. Discussion The results indicate that the global – local distinction is an unlikely explanation for the overestimated thresholds of TNO. Test protocol and disparities are one contributing factor. Potential additional factors include the nature of the task (TNO requires depth discrimination rather than detection) and the use of anaglyph red/green 3D glasses rather than polarizing filters, which may reduce binocular fusion.},
note = {_eprint: https://onlinelibrary.wiley.com/doi/pdf/10.1111/opo.12371},
keywords = {RESPONSEPixx},
pubstate = {published},
tppubtype = {article}
}
Purpose It has been repeatedly shown that the TNO stereotest overestimates stereo threshold compared to other clinical stereotests. In the current study, we test whether this overestimation can be attributed to a distinction between ‘global’ (or ‘cyclopean’) and ‘local’ (feature or contour-based) stereopsis. Methods We compared stereo thresholds of a global (TNO) and a local clinical stereotest (Randot Circles). In addition, a global and a local psychophysical stereotest were added to the design. One hundred and forty-nine children between 4 and 16 years old were included in the study. Results Stereo threshold estimates with TNO were a factor of two higher than with any of the other stereotests. No significant differences were found between the other tests. Bland-Altman analyses also indicated low agreement between TNO and the other stereotests, especially for higher stereo threshold estimates. Simulations indicated that the TNO test protocol and test disparities can account for part of this effect. Discussion The results indicate that the global – local distinction is an unlikely explanation for the overestimated thresholds of TNO. Test protocol and disparities are one contributing factor. Potential additional factors include the nature of the task (TNO requires depth discrimination rather than detection) and the use of anaglyph red/green 3D glasses rather than polarizing filters, which may reduce binocular fusion.
208.
Hesse, Philipp N.; Schmitt, Constanze; Klingenhoefer, Steffen; Bremmer, Frank
Preattentive Processing of Numerical Visual Information Journal Article
In: Frontiers in Human Neuroscience, vol. 11, 2017, ISSN: 1662-5161.
Abstract | Links | BibTeX | Tags: VIEWPixx3D
@article{hesse_preattentive_2017,
title = {Preattentive Processing of Numerical Visual Information},
author = {Philipp N. Hesse and Constanze Schmitt and Steffen Klingenhoefer and Frank Bremmer},
url = {https://www.frontiersin.org/articles/10.3389/fnhum.2017.00070},
issn = {1662-5161},
year = {2017},
date = {2017-01-01},
urldate = {2024-01-17},
journal = {Frontiers in Human Neuroscience},
volume = {11},
abstract = {Humans can perceive and estimate approximate numerical information, even when accurate counting is impossible e.g., due to short presentation time. If the number of objects to be estimated is small, typically around 1–4 items, observers are able to give very fast and precise judgments with high confidence—an effect that is called subitizing. Due to its speed and effortless nature subitizing has usually been assumed to be preattentive, putting it into the same category as other low level visual features like color or orientation. More recently, however, a number of studies have suggested that subitizing might be dependent on attentional resources. In our current study we investigated the potentially preattentive nature of visual numerical perception in the subitizing range by means of EEG. We presented peripheral, task irrelevant sequences of stimuli consisting of a certain number of circular patches while participants were engaged in a demanding, non-numerical detection task at the fixation point drawing attention away from the number stimuli. Within a sequence of stimuli of a given number of patches (called “standards”) we interspersed some stimuli of different numerosity (“oddballs”). We compared the evoked responses to visually identical stimuli that had been presented in two different conditions, serving as standard in one condition and as oddball in the other. We found significant visual mismatch negativity (vMMN) responses over parieto-occipital electrodes. In addition to the event-related potential (ERP) analysis, we performed a time-frequency analysis (TFA) to investigate whether the vMMN was accompanied by additional oscillatory processes. We found a concurrent increase in evoked theta power of similar strength over both hemispheres. Our results provide clear evidence for a preattentive processing of numerical visual information in the subitizing range.},
keywords = {VIEWPixx3D},
pubstate = {published},
tppubtype = {article}
}
Humans can perceive and estimate approximate numerical information, even when accurate counting is impossible e.g., due to short presentation time. If the number of objects to be estimated is small, typically around 1–4 items, observers are able to give very fast and precise judgments with high confidence—an effect that is called subitizing. Due to its speed and effortless nature subitizing has usually been assumed to be preattentive, putting it into the same category as other low level visual features like color or orientation. More recently, however, a number of studies have suggested that subitizing might be dependent on attentional resources. In our current study we investigated the potentially preattentive nature of visual numerical perception in the subitizing range by means of EEG. We presented peripheral, task irrelevant sequences of stimuli consisting of a certain number of circular patches while participants were engaged in a demanding, non-numerical detection task at the fixation point drawing attention away from the number stimuli. Within a sequence of stimuli of a given number of patches (called “standards”) we interspersed some stimuli of different numerosity (“oddballs”). We compared the evoked responses to visually identical stimuli that had been presented in two different conditions, serving as standard in one condition and as oddball in the other. We found significant visual mismatch negativity (vMMN) responses over parieto-occipital electrodes. In addition to the event-related potential (ERP) analysis, we performed a time-frequency analysis (TFA) to investigate whether the vMMN was accompanied by additional oscillatory processes. We found a concurrent increase in evoked theta power of similar strength over both hemispheres. Our results provide clear evidence for a preattentive processing of numerical visual information in the subitizing range.
209.
Ford, Talitha C.; Woods, Will; Crewther, David P.
In: NeuroImage: Clinical, vol. 16, pp. 383–389, 2017, ISSN: 2213-1582.
Abstract | Links | BibTeX | Tags: VPixxProgram
@article{ford_spatio-temporal_2017,
title = {Spatio-temporal source cluster analysis reveals fronto-temporal auditory change processing differences within a shared autistic and schizotypal trait phenotype},
author = {Talitha C. Ford and Will Woods and David P. Crewther},
url = {https://www.sciencedirect.com/science/article/pii/S2213158217300992},
doi = {10.1016/j.nicl.2017.04.022},
issn = {2213-1582},
year = {2017},
date = {2017-01-01},
urldate = {2024-01-17},
journal = {NeuroImage: Clinical},
volume = {16},
pages = {383–389},
abstract = {Social Disorganisation (SD) is a shared autistic and schizotypal phenotype that is present in the subclinical population. Auditory processing deficits, particularly in mismatch negativity/field (MMN/F) have been reported across both spectrum disorders. This study investigates differences in MMN/F cortical spatio-temporal source activity between higher and lower quintiles of the SD spectrum. Sixteen low (9 female) and 19 high (9 female) SD subclinical adults (18–40years) underwent magnetoencephalography (MEG) during an MMF paradigm where standard tones (50ms) were interrupted by infrequent duration deviants (100ms). Spatio-temporal source cluster analysis with permutation testing revealed no difference between the groups in source activation to the standard tone. To the deviant tone however, there was significantly reduced right hemisphere fronto-temporal and insular cortex activation for the high SD group (p= 0.038). The MMF, as a product of the cortical response to the deviant minus that to the standard, did not differ significantly between the high and low Social Disorganisation groups. These data demonstrate a deficit in right fronto-temporal processing of an auditory change for those with more of the shared SD phenotype, indicating that right fronto-temporal auditory processing may be associated with psychosocial functioning.},
keywords = {VPixxProgram},
pubstate = {published},
tppubtype = {article}
}
Social Disorganisation (SD) is a shared autistic and schizotypal phenotype that is present in the subclinical population. Auditory processing deficits, particularly in mismatch negativity/field (MMN/F) have been reported across both spectrum disorders. This study investigates differences in MMN/F cortical spatio-temporal source activity between higher and lower quintiles of the SD spectrum. Sixteen low (9 female) and 19 high (9 female) SD subclinical adults (18–40years) underwent magnetoencephalography (MEG) during an MMF paradigm where standard tones (50ms) were interrupted by infrequent duration deviants (100ms). Spatio-temporal source cluster analysis with permutation testing revealed no difference between the groups in source activation to the standard tone. To the deviant tone however, there was significantly reduced right hemisphere fronto-temporal and insular cortex activation for the high SD group (p= 0.038). The MMF, as a product of the cortical response to the deviant minus that to the standard, did not differ significantly between the high and low Social Disorganisation groups. These data demonstrate a deficit in right fronto-temporal processing of an auditory change for those with more of the shared SD phenotype, indicating that right fronto-temporal auditory processing may be associated with psychosocial functioning.
210.
Kilpeläinen, Markku; Theeuwes, Jan
Efficient Avoidance of the Penalty Zone in Human Eye Movements Journal Article
In: PLOS ONE, vol. 11, no. 12, pp. e0167956, 2016, ISSN: 1932-6203, (Publisher: Public Library of Science).
Abstract | Links | BibTeX | Tags: VIEWPixx
@article{kilpelainen_efficient_2016,
title = {Efficient Avoidance of the Penalty Zone in Human Eye Movements},
author = {Markku Kilpeläinen and Jan Theeuwes},
url = {https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0167956},
doi = {10.1371/journal.pone.0167956},
issn = {1932-6203},
year = {2016},
date = {2016-12-01},
urldate = {2024-01-03},
journal = {PLOS ONE},
volume = {11},
number = {12},
pages = {e0167956},
abstract = {People use eye movements extremely effectively to find objects of interest in a cluttered visual scene. Distracting, task-irrelevant attention capturing regions in the visual field should be avoided as they jeopardize the efficiency of search. In the current study, we used eye tracking to determine whether people are able to avoid making saccades to a predetermined visual area associated with a financial penalty, while making fast and accurate saccades towards stimuli placed near the penalty area. We found that in comparison to the same task without a penalty area, the introduction of a penalty area immediately affected eye movement behaviour: the proportion of saccades to the penalty area was immediately reduced. Also, saccadic latencies increased, but quite modestly, and mainly for saccades towards stimuli near the penalty area. We conclude that eye movement behaviour is under efficient cognitive control and thus quite flexible: it can immediately be adapted to changing environmental conditions to improve reward outcome.},
note = {Publisher: Public Library of Science},
keywords = {VIEWPixx},
pubstate = {published},
tppubtype = {article}
}
People use eye movements extremely effectively to find objects of interest in a cluttered visual scene. Distracting, task-irrelevant attention capturing regions in the visual field should be avoided as they jeopardize the efficiency of search. In the current study, we used eye tracking to determine whether people are able to avoid making saccades to a predetermined visual area associated with a financial penalty, while making fast and accurate saccades towards stimuli placed near the penalty area. We found that in comparison to the same task without a penalty area, the introduction of a penalty area immediately affected eye movement behaviour: the proportion of saccades to the penalty area was immediately reduced. Also, saccadic latencies increased, but quite modestly, and mainly for saccades towards stimuli near the penalty area. We conclude that eye movement behaviour is under efficient cognitive control and thus quite flexible: it can immediately be adapted to changing environmental conditions to improve reward outcome.
211.
Pinchuk-Yacobi, Noga; Dekel, Ron; Sagi, Dov
Expectations and visual aftereffects Journal Article
In: Journal of Vision, vol. 16, no. 15, pp. 19, 2016, ISSN: 1534-7362.
Abstract | Links | BibTeX | Tags: VIEWPixx3D
@article{pinchuk-yacobi_expectations_2016,
title = {Expectations and visual aftereffects},
author = {Noga Pinchuk-Yacobi and Ron Dekel and Dov Sagi},
url = {https://doi.org/10.1167/16.15.19},
doi = {10.1167/16.15.19},
issn = {1534-7362},
year = {2016},
date = {2016-12-01},
urldate = {2024-01-03},
journal = {Journal of Vision},
volume = {16},
number = {15},
pages = {19},
abstract = {The tilt aftereffect (TAE) is traditionally regarded as a consequence of orientation-selective sensory adaptation, a low-level stimulus-driven process. Adaptation has been recently suggested to be the outcome of predictive coding. Here, we tested whether the TAE is modulated by predictability, and specifically, whether TAE depends on the congruency of adapted and expected orientations. Observers were presented with successive pairs of oriented Gabor patches. Pairs were arranged in blocks, forming two conditions with the orientation of the second pair member either predictable or not. For all pairs, the orientation of the first Gabor was tilted clockwise (CW) or counterclockwise (CCW) (±20° relative to vertical, randomized). In the “Expected” conditions, the orientation of the second Gabor was fixed relative to the first Gabor (the same or a mirror orientation, blocked). In the “no-expectation” condition, the orientation of the second Gabor was independent of the first Gabor (randomized ±20°). Intermixed test pairs were used to measure observers' perceived vertical, with the second pair member serving as a target, oriented around the vertical, permitting an estimate of the TAE produced by the presentation of the first Gabor. Results show an increase in TAE with the expected orientation matching the inducing orientation, but a decrease with the expected mirror orientation, consistent with additivity of the adaptation and the expectation effects. A second experiment, with the first oriented Gabor replaced by a colored circular blob, showed that expectation alone does not modulate the perceived orientation. These findings indicate a role for expectation in generating the perceptual TAE and are in line with predictive coding models of perception. We suggest that orientation dependent adaptation is affected by both the mean orientation (first order statistics) and by temporal contingencies (second order statistics).},
keywords = {VIEWPixx3D},
pubstate = {published},
tppubtype = {article}
}
The tilt aftereffect (TAE) is traditionally regarded as a consequence of orientation-selective sensory adaptation, a low-level stimulus-driven process. Adaptation has been recently suggested to be the outcome of predictive coding. Here, we tested whether the TAE is modulated by predictability, and specifically, whether TAE depends on the congruency of adapted and expected orientations. Observers were presented with successive pairs of oriented Gabor patches. Pairs were arranged in blocks, forming two conditions with the orientation of the second pair member either predictable or not. For all pairs, the orientation of the first Gabor was tilted clockwise (CW) or counterclockwise (CCW) (±20° relative to vertical, randomized). In the “Expected” conditions, the orientation of the second Gabor was fixed relative to the first Gabor (the same or a mirror orientation, blocked). In the “no-expectation” condition, the orientation of the second Gabor was independent of the first Gabor (randomized ±20°). Intermixed test pairs were used to measure observers' perceived vertical, with the second pair member serving as a target, oriented around the vertical, permitting an estimate of the TAE produced by the presentation of the first Gabor. Results show an increase in TAE with the expected orientation matching the inducing orientation, but a decrease with the expected mirror orientation, consistent with additivity of the adaptation and the expectation effects. A second experiment, with the first oriented Gabor replaced by a colored circular blob, showed that expectation alone does not modulate the perceived orientation. These findings indicate a role for expectation in generating the perceptual TAE and are in line with predictive coding models of perception. We suggest that orientation dependent adaptation is affected by both the mean orientation (first order statistics) and by temporal contingencies (second order statistics).
212.
Baker, Daniel H.; Kaestner, Milena; Gouws, André D.
Measurement of crosstalk in stereoscopic display systems used for vision research Journal Article
In: Journal of Vision, vol. 16, no. 15, pp. 14, 2016, ISSN: 1534-7362.
Abstract | Links | BibTeX | Tags: 3DPixx, 3DPolarizer, PROPixx, VIEWPixx3D
@article{baker_measurement_2016,
title = {Measurement of crosstalk in stereoscopic display systems used for vision research},
author = {Daniel H. Baker and Milena Kaestner and André D. Gouws},
url = {https://doi.org/10.1167/16.15.14},
doi = {10.1167/16.15.14},
issn = {1534-7362},
year = {2016},
date = {2016-12-01},
urldate = {2024-01-12},
journal = {Journal of Vision},
volume = {16},
number = {15},
pages = {14},
abstract = {Studying binocular vision requires precise control over the stimuli presented to the left and right eyes. A popular technique is to segregate signals either temporally (frame interleaving), spectrally (using colored filters), or through light polarization. None of these segregation methods achieves perfect isolation, and so a degree of crosstalk is usually apparent, in which signals intended for one eye are faintly visible to the other eye. Previous studies have reported crosstalk values mostly for consumer-grade systems. Here we measure crosstalk for eight systems, many of which are intended for use in vision research. We provide benchmark crosstalk values, report a negative crosstalk effect in some LCD-based systems, and give guidelines for dealing with crosstalk in different experimental paradigms.},
keywords = {3DPixx, 3DPolarizer, PROPixx, VIEWPixx3D},
pubstate = {published},
tppubtype = {article}
}
Studying binocular vision requires precise control over the stimuli presented to the left and right eyes. A popular technique is to segregate signals either temporally (frame interleaving), spectrally (using colored filters), or through light polarization. None of these segregation methods achieves perfect isolation, and so a degree of crosstalk is usually apparent, in which signals intended for one eye are faintly visible to the other eye. Previous studies have reported crosstalk values mostly for consumer-grade systems. Here we measure crosstalk for eight systems, many of which are intended for use in vision research. We provide benchmark crosstalk values, report a negative crosstalk effect in some LCD-based systems, and give guidelines for dealing with crosstalk in different experimental paradigms.
213.
Luo-Li, Gloria; Alais, David; Freeman, Alan W.
Orientation discrimination requires coactivation of on- and off-dominated visual channels Journal Article
In: Journal of Vision, vol. 16, no. 15, pp. 18, 2016, ISSN: 1534-7362.
Abstract | Links | BibTeX | Tags: RESPONSEPixx, VIEWPixx
@article{luo-li_orientation_2016,
title = {Orientation discrimination requires coactivation of on- and off-dominated visual channels},
author = {Gloria Luo-Li and David Alais and Alan W. Freeman},
url = {https://doi.org/10.1167/16.15.18},
doi = {10.1167/16.15.18},
issn = {1534-7362},
year = {2016},
date = {2016-12-01},
urldate = {2024-01-16},
journal = {Journal of Vision},
volume = {16},
number = {15},
pages = {18},
abstract = {Orientation sensitivity depends on the cortical convergence of on- and off-center subcortical neurons. Off-center inputs are faster and stronger than their on-center counterparts: How does this asymmetry affect orientation discrimination? We tackled this question psychophysically with grating stimuli that either increased or decreased luminance. The gratings were of low contrast in order to avoid the complicating influences of nonlinearities such as response saturation, masking, and aftereffects. Gratings were presented in either of two locations, and subjects indicated the perceived location. Stimuli were randomly timed, and response correctness and reaction time were recorded. We found the following: (a) Contrast sensitivity was insignificant for a range of contrasts around zero. (b) Outside this range, contrast sensitivity for contrast decrements exceeded that for increments by an average of 15%. (c) Reaction times for contrast decrements were up to 45 ms less than for increments. (d) These findings are reproduced by a signal-detection model which incorporates recent physiological findings: Neurons in primary visual cortex are hyperpolarized at rest; these neurons respond more to darks than to lights; and off-dominated cortical neurons have shorter latencies than their on-dominated neighbors. (e) We tested orientation discrimination by splitting a grating into two components, one containing the light bars and the other the dark, and presenting the two components asynchronously. Discrimination was optimal when light bars preceded dark bars, consistent with coactivation of on- and off-center cortical inputs. We conclude that the ability to discriminate between orientations is intimately connected with the properties of subcortical channels.},
keywords = {RESPONSEPixx, VIEWPixx},
pubstate = {published},
tppubtype = {article}
}
Orientation sensitivity depends on the cortical convergence of on- and off-center subcortical neurons. Off-center inputs are faster and stronger than their on-center counterparts: How does this asymmetry affect orientation discrimination? We tackled this question psychophysically with grating stimuli that either increased or decreased luminance. The gratings were of low contrast in order to avoid the complicating influences of nonlinearities such as response saturation, masking, and aftereffects. Gratings were presented in either of two locations, and subjects indicated the perceived location. Stimuli were randomly timed, and response correctness and reaction time were recorded. We found the following: (a) Contrast sensitivity was insignificant for a range of contrasts around zero. (b) Outside this range, contrast sensitivity for contrast decrements exceeded that for increments by an average of 15%. (c) Reaction times for contrast decrements were up to 45 ms less than for increments. (d) These findings are reproduced by a signal-detection model which incorporates recent physiological findings: Neurons in primary visual cortex are hyperpolarized at rest; these neurons respond more to darks than to lights; and off-dominated cortical neurons have shorter latencies than their on-dominated neighbors. (e) We tested orientation discrimination by splitting a grating into two components, one containing the light bars and the other the dark, and presenting the two components asynchronously. Discrimination was optimal when light bars preceded dark bars, consistent with coactivation of on- and off-center cortical inputs. We conclude that the ability to discriminate between orientations is intimately connected with the properties of subcortical channels.
214.
Hornsey, Rebecca L.; Hibbard, Paul B.; Scarfe, Peter
Binocular Depth Judgments on Smoothly Curved Surfaces Journal Article
In: PLOS ONE, vol. 11, no. 11, pp. e0165932, 2016, ISSN: 1932-6203, (Publisher: Public Library of Science).
Abstract | Links | BibTeX | Tags: 3DPixx, RESPONSEPixx, VIEWPixx3D
@article{hornsey_binocular_2016,
title = {Binocular Depth Judgments on Smoothly Curved Surfaces},
author = {Rebecca L. Hornsey and Paul B. Hibbard and Peter Scarfe},
url = {https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0165932},
doi = {10.1371/journal.pone.0165932},
issn = {1932-6203},
year = {2016},
date = {2016-11-01},
urldate = {2023-12-22},
journal = {PLOS ONE},
volume = {11},
number = {11},
pages = {e0165932},
abstract = {Binocular disparity is an important cue to depth, allowing us to make very fine discriminations of the relative depth of objects. In complex scenes, this sensitivity depends on the particular shape and layout of the objects viewed. For example, judgments of the relative depths of points on a smoothly curved surface are less accurate than those for points in empty space. It has been argued that this occurs because depth relationships are represented accurately only within a local spatial area. A consequence of this is that, when judging the relative depths of points separated by depth maxima and minima, information must be integrated across separate local representations. This integration, by adding more stages of processing, might be expected to reduce the accuracy of depth judgements. We tested this idea directly by measuring how accurately human participants could report the relative depths of two dots, presented with different binocular disparities. In the first, Two Dot condition the two dots were presented in front of a square grid. In the second, Three Dot condition, an additional dot was presented midway between the target dots, at a range of depths, both nearer and further than the target dots. In the final, Surface condition, the target dots were placed on a smooth surface defined by binocular disparity cues. In some trials, this contained a depth maximum or minimum between the target dots. In the Three Dot condition, performance was impaired when the central dot was presented with a large disparity, in line with predictions. In the Surface condition, performance was worst when the midpoint of the surface was at a similar distance to the targets, and relatively unaffected when there was a large depth maximum or minimum present. These results are not consistent with the idea that depth order is represented only within a local spatial area.},
note = {Publisher: Public Library of Science},
keywords = {3DPixx, RESPONSEPixx, VIEWPixx3D},
pubstate = {published},
tppubtype = {article}
}
Binocular disparity is an important cue to depth, allowing us to make very fine discriminations of the relative depth of objects. In complex scenes, this sensitivity depends on the particular shape and layout of the objects viewed. For example, judgments of the relative depths of points on a smoothly curved surface are less accurate than those for points in empty space. It has been argued that this occurs because depth relationships are represented accurately only within a local spatial area. A consequence of this is that, when judging the relative depths of points separated by depth maxima and minima, information must be integrated across separate local representations. This integration, by adding more stages of processing, might be expected to reduce the accuracy of depth judgements. We tested this idea directly by measuring how accurately human participants could report the relative depths of two dots, presented with different binocular disparities. In the first, Two Dot condition the two dots were presented in front of a square grid. In the second, Three Dot condition, an additional dot was presented midway between the target dots, at a range of depths, both nearer and further than the target dots. In the final, Surface condition, the target dots were placed on a smooth surface defined by binocular disparity cues. In some trials, this contained a depth maximum or minimum between the target dots. In the Three Dot condition, performance was impaired when the central dot was presented with a large disparity, in line with predictions. In the Surface condition, performance was worst when the midpoint of the surface was at a similar distance to the targets, and relatively unaffected when there was a large depth maximum or minimum present. These results are not consistent with the idea that depth order is represented only within a local spatial area.
215.
Alwis, Dasuni S.; Richards, Katrina L.; Price, Nicholas S. C.
Masking reduces orientation selectivity in rat visual cortex Journal Article
In: Journal of Neurophysiology, vol. 116, no. 5, pp. 2331–2341, 2016, ISSN: 0022-3077.
Abstract | Links | BibTeX | Tags: VIEWPixx3D
@article{alwis_masking_2016,
title = {Masking reduces orientation selectivity in rat visual cortex},
author = {Dasuni S. Alwis and Katrina L. Richards and Nicholas S. C. Price},
url = {https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5110635/},
doi = {10.1152/jn.00366.2016},
issn = {0022-3077},
year = {2016},
date = {2016-11-01},
urldate = {2024-01-12},
journal = {Journal of Neurophysiology},
volume = {116},
number = {5},
pages = {2331–2341},
abstract = {We examined how masks that preceded or succeeded oriented target stimuli affected neuronal responses in rat primary visual cortex. Regardless of the spatial or temporal arrangement of stimuli, the greatest reductions in firing rate and orientation selectivity occurred when target and mask appeared closely in time. On the basis of our neuronal data, we suggest that monotonic patterns of perceptual visual masking are explained by a combination of long neural integration windows and lateral inhibition., In visual masking the perception of a target stimulus is impaired by a preceding (forward) or succeeding (backward) mask stimulus. The illusion is of interest because it allows uncoupling of the physical stimulus, its neuronal representation, and its perception. To understand the neuronal correlates of masking, we examined how masks affected the neuronal responses to oriented target stimuli in the primary visual cortex (V1) of anesthetized rats (n = 37). Target stimuli were circular gratings with 12 orientations; mask stimuli were plaids created as a binarized sum of all possible target orientations. Spatially, masks were presented either overlapping or surrounding the target. Temporally, targets and masks were presented for 33 ms, but the stimulus onset asynchrony (SOA) of their relative appearance was varied. For the first time, we examine how spatially overlapping and center-surround masking affect orientation discriminability (rather than visibility) in V1. Regardless of the spatial or temporal arrangement of stimuli, the greatest reductions in firing rate and orientation selectivity occurred for the shortest SOAs. Interestingly, analyses conducted separately for transient and sustained target response components showed that changes in orientation selectivity do not always coincide with changes in firing rate. Given the near-instantaneous reductions observed in orientation selectivity even when target and mask do not spatially overlap, we suggest that monotonic visual masking is explained by a combination of neural integration and lateral inhibition.},
keywords = {VIEWPixx3D},
pubstate = {published},
tppubtype = {article}
}
We examined how masks that preceded or succeeded oriented target stimuli affected neuronal responses in rat primary visual cortex. Regardless of the spatial or temporal arrangement of stimuli, the greatest reductions in firing rate and orientation selectivity occurred when target and mask appeared closely in time. On the basis of our neuronal data, we suggest that monotonic patterns of perceptual visual masking are explained by a combination of long neural integration windows and lateral inhibition., In visual masking the perception of a target stimulus is impaired by a preceding (forward) or succeeding (backward) mask stimulus. The illusion is of interest because it allows uncoupling of the physical stimulus, its neuronal representation, and its perception. To understand the neuronal correlates of masking, we examined how masks affected the neuronal responses to oriented target stimuli in the primary visual cortex (V1) of anesthetized rats (n = 37). Target stimuli were circular gratings with 12 orientations; mask stimuli were plaids created as a binarized sum of all possible target orientations. Spatially, masks were presented either overlapping or surrounding the target. Temporally, targets and masks were presented for 33 ms, but the stimulus onset asynchrony (SOA) of their relative appearance was varied. For the first time, we examine how spatially overlapping and center-surround masking affect orientation discriminability (rather than visibility) in V1. Regardless of the spatial or temporal arrangement of stimuli, the greatest reductions in firing rate and orientation selectivity occurred for the shortest SOAs. Interestingly, analyses conducted separately for transient and sustained target response components showed that changes in orientation selectivity do not always coincide with changes in firing rate. Given the near-instantaneous reductions observed in orientation selectivity even when target and mask do not spatially overlap, we suggest that monotonic visual masking is explained by a combination of neural integration and lateral inhibition.
216.
Hagmann, Carl Erick; Russo, Natalie
Multisensory integration of redundant trisensory stimulation Journal Article
In: Attention, Perception, & Psychophysics, vol. 78, no. 8, pp. 2558–2568, 2016, ISSN: 1943-393X.
Abstract | Links | BibTeX | Tags: VIEWPixx
@article{hagmann_multisensory_2016,
title = {Multisensory integration of redundant trisensory stimulation},
author = {Carl Erick Hagmann and Natalie Russo},
url = {https://doi.org/10.3758/s13414-016-1192-6},
doi = {10.3758/s13414-016-1192-6},
issn = {1943-393X},
year = {2016},
date = {2016-11-01},
urldate = {2024-01-12},
journal = {Attention, Perception, & Psychophysics},
volume = {78},
number = {8},
pages = {2558–2568},
abstract = {Integration of sensory information across modalities can confer behavioral advantages by decreasing perceptual ambiguity, increasing reaction time, and increasing detection accuracy relative to unisensory stimuli. We asked how combinations of auditory, visual, and somatosensory events alter response time. Participants detected stimulation on one side of space (right or left) while ignoring stimulation on the other side of space. There were seven types of suprathreshold stimuli: auditory (tones from speakers), visual (sinusoidal contrast gratings), somatosensory (fingertip vibrations), audio-visual, somato-visual, audio-somatosensory, and audio-somato-visual. Response enhancement and race model analysis confirmed that bisensory and trisensory trials enhanced response time relative to unisensory trials. Exploratory analysis of individual differences in intersensory facilitation revealed that participants fit into one of two groups: those who benefitted from trisensory information and those who did not.},
keywords = {VIEWPixx},
pubstate = {published},
tppubtype = {article}
}
Integration of sensory information across modalities can confer behavioral advantages by decreasing perceptual ambiguity, increasing reaction time, and increasing detection accuracy relative to unisensory stimuli. We asked how combinations of auditory, visual, and somatosensory events alter response time. Participants detected stimulation on one side of space (right or left) while ignoring stimulation on the other side of space. There were seven types of suprathreshold stimuli: auditory (tones from speakers), visual (sinusoidal contrast gratings), somatosensory (fingertip vibrations), audio-visual, somato-visual, audio-somatosensory, and audio-somato-visual. Response enhancement and race model analysis confirmed that bisensory and trisensory trials enhanced response time relative to unisensory trials. Exploratory analysis of individual differences in intersensory facilitation revealed that participants fit into one of two groups: those who benefitted from trisensory information and those who did not.
217.
Utz, Sandra; Carbon, Claus-Christian
Is the Thatcher Illusion Modulated by Face Familiarity? Evidence from an Eye Tracking Study Journal Article
In: PLOS ONE, vol. 11, no. 10, pp. e0163933, 2016, ISSN: 1932-6203, (Publisher: Public Library of Science).
Abstract | Links | BibTeX | Tags: RESPONSEPixx
@article{utz_is_2016,
title = {Is the Thatcher Illusion Modulated by Face Familiarity? Evidence from an Eye Tracking Study},
author = {Sandra Utz and Claus-Christian Carbon},
url = {https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0163933},
doi = {10.1371/journal.pone.0163933},
issn = {1932-6203},
year = {2016},
date = {2016-10-01},
urldate = {2024-01-08},
journal = {PLOS ONE},
volume = {11},
number = {10},
pages = {e0163933},
abstract = {Thompson (1980) first detected and described the Thatcher Illusion, where participants instantly perceive an upright face with inverted eyes and mouth as grotesque, but fail to do so when the same face is inverted. One prominent but controversial explanation is that the processing of configural information is disrupted in inverted faces. Studies investigating the Thatcher Illusion either used famous faces or non-famous faces. Highly familiar faces were often thought to be processed in a pronounced configural mode, so they seem ideal candidates to be tested in one Thatcher study against unfamiliar faces–but this has never been addressed so far. In our study, participants evaluated 16 famous and 16 non-famous faces for their grotesqueness. We tested whether familiarity (famous/non-famous faces) modulates reaction times, correctness of grotesqueness assessments (accuracy), and eye movement patterns for the factors orientation (upright/inverted) and Thatcherisation (Thatcherised/non-Thatcherised). On a behavioural level, familiarity effects were only observable via face inversion (higher accuracy and sensitivity for famous compared to non-famous faces) but not via Thatcherisation. Regarding eye movements, however, Thatcherisation influenced the scanning of famous and non-famous faces, for instance, in scanning the mouth region of the presented faces (higher number, duration and dwell time of fixations for famous compared to non-famous faces if Thatcherised). Altogether, famous faces seem to be processed in a more elaborate, more expertise-based way than non-famous faces, whereas non-famous, inverted faces seem to cause difficulties in accurate and sensitive processing. Results are further discussed in the face of existing studies of familiar vs. unfamiliar face processing.},
note = {Publisher: Public Library of Science},
keywords = {RESPONSEPixx},
pubstate = {published},
tppubtype = {article}
}
Thompson (1980) first detected and described the Thatcher Illusion, where participants instantly perceive an upright face with inverted eyes and mouth as grotesque, but fail to do so when the same face is inverted. One prominent but controversial explanation is that the processing of configural information is disrupted in inverted faces. Studies investigating the Thatcher Illusion either used famous faces or non-famous faces. Highly familiar faces were often thought to be processed in a pronounced configural mode, so they seem ideal candidates to be tested in one Thatcher study against unfamiliar faces–but this has never been addressed so far. In our study, participants evaluated 16 famous and 16 non-famous faces for their grotesqueness. We tested whether familiarity (famous/non-famous faces) modulates reaction times, correctness of grotesqueness assessments (accuracy), and eye movement patterns for the factors orientation (upright/inverted) and Thatcherisation (Thatcherised/non-Thatcherised). On a behavioural level, familiarity effects were only observable via face inversion (higher accuracy and sensitivity for famous compared to non-famous faces) but not via Thatcherisation. Regarding eye movements, however, Thatcherisation influenced the scanning of famous and non-famous faces, for instance, in scanning the mouth region of the presented faces (higher number, duration and dwell time of fixations for famous compared to non-famous faces if Thatcherised). Altogether, famous faces seem to be processed in a more elaborate, more expertise-based way than non-famous faces, whereas non-famous, inverted faces seem to cause difficulties in accurate and sensitive processing. Results are further discussed in the face of existing studies of familiar vs. unfamiliar face processing.
218.
Joo, Sung Jun; Czuba, Thaddeus B.; Cormack, Lawrence K.; Huk, Alexander C.
Separate Perceptual and Neural Processing of Velocity- and Disparity-Based 3D Motion Signals Journal Article
In: Journal of Neuroscience, vol. 36, no. 42, pp. 10791–10802, 2016, ISSN: 0270-6474, 1529-2401, (Publisher: Society for Neuroscience Section: Research Articles).
Abstract | Links | BibTeX | Tags: 3DPolarizer, PROPixx
@article{joo_separate_2016,
title = {Separate Perceptual and Neural Processing of Velocity- and Disparity-Based 3D Motion Signals},
author = {Sung Jun Joo and Thaddeus B. Czuba and Lawrence K. Cormack and Alexander C. Huk},
url = {https://www.jneurosci.org/content/36/42/10791},
doi = {10.1523/JNEUROSCI.1298-16.2016},
issn = {0270-6474, 1529-2401},
year = {2016},
date = {2016-10-01},
urldate = {2024-01-17},
journal = {Journal of Neuroscience},
volume = {36},
number = {42},
pages = {10791–10802},
abstract = {Although the visual system uses both velocity- and disparity-based binocular information for computing 3D motion, it is unknown whether (and how) these two signals interact. We found that these two binocular signals are processed distinctly at the levels of both cortical activity in human MT and perception. In human MT, adaptation to both velocity-based and disparity-based 3D motions demonstrated direction-selective neuroimaging responses. However, when adaptation to one cue was probed using the other cue, there was no evidence of interaction between them (i.e., there was no “cross-cue” adaptation). Analogous psychophysical measurements yielded correspondingly weak cross-cue motion aftereffects (MAEs) in the face of very strong within-cue adaptation. In a direct test of perceptual independence, adapting to opposite 3D directions generated by different binocular cues resulted in simultaneous, superimposed, opposite-direction MAEs. These findings suggest that velocity- and disparity-based 3D motion signals may both flow through area MT but constitute distinct signals and pathways.
SIGNIFICANCE STATEMENT Recent human neuroimaging and monkey electrophysiology have revealed 3D motion selectivity in area MT, which is driven by both velocity-based and disparity-based 3D motion signals. However, to elucidate the neural mechanisms by which the brain extracts 3D motion given these binocular signals, it is essential to understand how—or indeed if—these two binocular cues interact. We show that velocity-based and disparity-based signals are mostly separate at the levels of both fMRI responses in area MT and perception. Our findings suggest that the two binocular cues for 3D motion might be processed by separate specialized mechanisms.},
note = {Publisher: Society for Neuroscience
Section: Research Articles},
keywords = {3DPolarizer, PROPixx},
pubstate = {published},
tppubtype = {article}
}
Although the visual system uses both velocity- and disparity-based binocular information for computing 3D motion, it is unknown whether (and how) these two signals interact. We found that these two binocular signals are processed distinctly at the levels of both cortical activity in human MT and perception. In human MT, adaptation to both velocity-based and disparity-based 3D motions demonstrated direction-selective neuroimaging responses. However, when adaptation to one cue was probed using the other cue, there was no evidence of interaction between them (i.e., there was no “cross-cue” adaptation). Analogous psychophysical measurements yielded correspondingly weak cross-cue motion aftereffects (MAEs) in the face of very strong within-cue adaptation. In a direct test of perceptual independence, adapting to opposite 3D directions generated by different binocular cues resulted in simultaneous, superimposed, opposite-direction MAEs. These findings suggest that velocity- and disparity-based 3D motion signals may both flow through area MT but constitute distinct signals and pathways.
SIGNIFICANCE STATEMENT Recent human neuroimaging and monkey electrophysiology have revealed 3D motion selectivity in area MT, which is driven by both velocity-based and disparity-based 3D motion signals. However, to elucidate the neural mechanisms by which the brain extracts 3D motion given these binocular signals, it is essential to understand how—or indeed if—these two binocular cues interact. We show that velocity-based and disparity-based signals are mostly separate at the levels of both fMRI responses in area MT and perception. Our findings suggest that the two binocular cues for 3D motion might be processed by separate specialized mechanisms.
SIGNIFICANCE STATEMENT Recent human neuroimaging and monkey electrophysiology have revealed 3D motion selectivity in area MT, which is driven by both velocity-based and disparity-based 3D motion signals. However, to elucidate the neural mechanisms by which the brain extracts 3D motion given these binocular signals, it is essential to understand how—or indeed if—these two binocular cues interact. We show that velocity-based and disparity-based signals are mostly separate at the levels of both fMRI responses in area MT and perception. Our findings suggest that the two binocular cues for 3D motion might be processed by separate specialized mechanisms.
219.
Wiebel, Christiane B.; Singh, Manish; Maertens, Marianne
Testing the role of Michelson contrast for the perception of surface lightness Journal Article
In: Journal of Vision, vol. 16, no. 11, pp. 17, 2016, ISSN: 1534-7362.
Abstract | Links | BibTeX | Tags: DATAPixx, RESPONSEPixx
@article{wiebel_testing_2016,
title = {Testing the role of Michelson contrast for the perception of surface lightness},
author = {Christiane B. Wiebel and Manish Singh and Marianne Maertens},
url = {https://doi.org/10.1167/16.11.17},
doi = {10.1167/16.11.17},
issn = {1534-7362},
year = {2016},
date = {2016-09-01},
urldate = {2024-01-18},
journal = {Journal of Vision},
volume = {16},
number = {11},
pages = {17},
abstract = {It is still an unresolved question how the visual system perceives surface lightness given the ambiguity of the sensory input signal. We studied lightness perception using two-dimensional images of variegated checkerboards shown as perspective projections of three-dimensional objects. We manipulated the contrast of a target check relative to its surround either by rendering the image under different viewing conditions or by introducing noncoincidental changes of the reflectance of the surfaces adjacent to the target. We examined the predictive power of the normalized contrast model (Zeiner & Maertens, 2014) for the different viewing conditions (plain view vs. dark and light transparency) as well as for the noncoincidental surround changes (only high or only low reflectances in the surround). The model accounted for lightness matches across different viewing conditions but not for the surround changes. The observed simultaneous contrast effects were smaller than what would be predicted by the model. We evaluated two model extensions that—both relying on contrast—predicted the observed data well. Both model extensions point to the importance of contrast statistics across space and/or time for the computation of lightness, but it awaits future testing to evaluate whether and how the visual system could represent such statistics.},
keywords = {DATAPixx, RESPONSEPixx},
pubstate = {published},
tppubtype = {article}
}
It is still an unresolved question how the visual system perceives surface lightness given the ambiguity of the sensory input signal. We studied lightness perception using two-dimensional images of variegated checkerboards shown as perspective projections of three-dimensional objects. We manipulated the contrast of a target check relative to its surround either by rendering the image under different viewing conditions or by introducing noncoincidental changes of the reflectance of the surfaces adjacent to the target. We examined the predictive power of the normalized contrast model (Zeiner & Maertens, 2014) for the different viewing conditions (plain view vs. dark and light transparency) as well as for the noncoincidental surround changes (only high or only low reflectances in the surround). The model accounted for lightness matches across different viewing conditions but not for the surround changes. The observed simultaneous contrast effects were smaller than what would be predicted by the model. We evaluated two model extensions that—both relying on contrast—predicted the observed data well. Both model extensions point to the importance of contrast statistics across space and/or time for the computation of lightness, but it awaits future testing to evaluate whether and how the visual system could represent such statistics.
220.
Kim, Seha; Burge, Johannes
Human tilt estimation in local patches with natural stereo-images Journal Article
In: Journal of Vision, vol. 16, no. 12, pp. 1413, 2016, ISSN: 1534-7362.
Abstract | Links | BibTeX | Tags: PROPixx
@article{kim_human_2016,
title = {Human tilt estimation in local patches with natural stereo-images},
author = {Seha Kim and Johannes Burge},
url = {https://doi.org/10.1167/16.12.1413},
doi = {10.1167/16.12.1413},
issn = {1534-7362},
year = {2016},
date = {2016-09-01},
urldate = {2023-12-21},
journal = {Journal of Vision},
volume = {16},
number = {12},
pages = {1413},
abstract = {Estimating 3D surface orientation (i.e. slant and tilt) is an important first step toward estimating 3D shape. To understand how different image cues are combined for surface orientation estimation, we examine human estimation of tilt in stereo-images of natural scenes. First, we built a custom display system with a stereo-enabled Vpixx ProPixx projector and a Harkness Clarus 140 polarization-maintaining screen. Next, we obtained a large database of stereo-images of natural scenes with precisely co-registered range data. These stereo-images provide rich cues that influence surface orientation perception; the range data provides the ground-truth tilt, slant, and distance at each pixel. We binned the range data according to local tilt, slant, and distance and randomly sampled corresponding 1deg image patches within each bin. Then, we assessed human tilt estimation using these patches. Human observers sat 3m from the screen such that the left and right retinal images were identical to the images that would have been formed by the original scene. On each trial, observers binocularly viewed a patch of scene through a 1deg aperture. The task was to estimate tilt of the depicted surface using a mouse-controlled probe. We compared human estimates of tilt to ground-truth tilt computed directly from the range data. A rich set of results emerged. First, human tilt estimation was generally accurate but was biased towards the cardinal tilts (i.e. 0, 90, 180deg: tilts of surfaces slanted about vertical and horizontal axes). Second, tilt estimation error varied systematically with ground-truth tilt: errors at the cardinal tilts were lower than at other tilts. Third, the pattern of human biases and errors matched the performance of a previously developed ideal observer for 3D surface tilt estimation in natural scenes (Burge & Geisler, 2015). Thus, our preliminary findings suggest human observers may optimally process local cues to 3D surface orientation. Meeting abstract presented at VSS 2016},
keywords = {PROPixx},
pubstate = {published},
tppubtype = {article}
}
Estimating 3D surface orientation (i.e. slant and tilt) is an important first step toward estimating 3D shape. To understand how different image cues are combined for surface orientation estimation, we examine human estimation of tilt in stereo-images of natural scenes. First, we built a custom display system with a stereo-enabled Vpixx ProPixx projector and a Harkness Clarus 140 polarization-maintaining screen. Next, we obtained a large database of stereo-images of natural scenes with precisely co-registered range data. These stereo-images provide rich cues that influence surface orientation perception; the range data provides the ground-truth tilt, slant, and distance at each pixel. We binned the range data according to local tilt, slant, and distance and randomly sampled corresponding 1deg image patches within each bin. Then, we assessed human tilt estimation using these patches. Human observers sat 3m from the screen such that the left and right retinal images were identical to the images that would have been formed by the original scene. On each trial, observers binocularly viewed a patch of scene through a 1deg aperture. The task was to estimate tilt of the depicted surface using a mouse-controlled probe. We compared human estimates of tilt to ground-truth tilt computed directly from the range data. A rich set of results emerged. First, human tilt estimation was generally accurate but was biased towards the cardinal tilts (i.e. 0, 90, 180deg: tilts of surfaces slanted about vertical and horizontal axes). Second, tilt estimation error varied systematically with ground-truth tilt: errors at the cardinal tilts were lower than at other tilts. Third, the pattern of human biases and errors matched the performance of a previously developed ideal observer for 3D surface tilt estimation in natural scenes (Burge & Geisler, 2015). Thus, our preliminary findings suggest human observers may optimally process local cues to 3D surface orientation. Meeting abstract presented at VSS 2016