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.
Want to have your work added to our library? Send us a message at [email protected] and we will add it. Your article must be peer-reviewed, open access, and it must indicate VPixx products were used in the research.
Use the search tool below to search for specific terms among the titles, authors and abstracts in our library.
1.
Weise, Annekathrin; Hartmann, Thomas; Parmentier, Fabrice; Weisz, Nathan; Ruhnau, Philipp
Involuntary shifts of spatial attention contribute to distraction—Evidence from oscillatory alpha power and reaction time data Journal Article
In: Psychophysiology, vol. 60, no. 10, pp. e14353, 2023, ISSN: 1469-8986, (_eprint: https://onlinelibrary.wiley.com/doi/pdf/10.1111/psyp.14353).
Abstract | Links | BibTeX | Tags: DATAPixx2, PROPixx, RESPONSEPixxMRI, SOUNDPixx
@article{weise_involuntary_2023,
title = {Involuntary shifts of spatial attention contribute to distraction—Evidence from oscillatory alpha power and reaction time data},
author = {Annekathrin Weise and Thomas Hartmann and Fabrice Parmentier and Nathan Weisz and Philipp Ruhnau},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/psyp.14353},
doi = {10.1111/psyp.14353},
issn = {1469-8986},
year = {2023},
date = {2023-01-01},
urldate = {2023-12-21},
journal = {Psychophysiology},
volume = {60},
number = {10},
pages = {e14353},
abstract = {Imagine you are focusing on the traffic on a busy street to ride your bike safely when suddenly you hear the siren of an ambulance. This unexpected sound involuntarily captures your attention and interferes with ongoing performance. We tested whether this type of distraction involves a spatial shift of attention. We measured behavioral data and magnetoencephalographic alpha power during a cross-modal paradigm that combined an exogenous cueing task and a distraction task. In each trial, a task-irrelevant sound preceded a visual target (left or right). The sound was usually the same animal sound (i.e., standard sound). Rarely, it was replaced by an unexpected environmental sound (i.e., deviant sound). Fifty percent of the deviants occurred on the same side as the target, and 50% occurred on the opposite side. Participants responded to the location of the target. As expected, responses were slower to targets that followed a deviant compared to a standard. Crucially, this distraction effect was mitigated by the spatial relationship between the targets and the deviants: responses were faster when targets followed deviants on the same versus different side, indexing a spatial shift of attention. This was further corroborated by a posterior alpha power modulation that was higher in the hemisphere ipsilateral (vs. contralateral) to the location of the attention-capturing deviant. We suggest that this alpha power lateralization reflects a spatial attention bias. Overall, our data support the contention that spatial shifts of attention contribute to deviant distraction.},
note = {_eprint: https://onlinelibrary.wiley.com/doi/pdf/10.1111/psyp.14353},
keywords = {DATAPixx2, PROPixx, RESPONSEPixxMRI, SOUNDPixx},
pubstate = {published},
tppubtype = {article}
}
Imagine you are focusing on the traffic on a busy street to ride your bike safely when suddenly you hear the siren of an ambulance. This unexpected sound involuntarily captures your attention and interferes with ongoing performance. We tested whether this type of distraction involves a spatial shift of attention. We measured behavioral data and magnetoencephalographic alpha power during a cross-modal paradigm that combined an exogenous cueing task and a distraction task. In each trial, a task-irrelevant sound preceded a visual target (left or right). The sound was usually the same animal sound (i.e., standard sound). Rarely, it was replaced by an unexpected environmental sound (i.e., deviant sound). Fifty percent of the deviants occurred on the same side as the target, and 50% occurred on the opposite side. Participants responded to the location of the target. As expected, responses were slower to targets that followed a deviant compared to a standard. Crucially, this distraction effect was mitigated by the spatial relationship between the targets and the deviants: responses were faster when targets followed deviants on the same versus different side, indexing a spatial shift of attention. This was further corroborated by a posterior alpha power modulation that was higher in the hemisphere ipsilateral (vs. contralateral) to the location of the attention-capturing deviant. We suggest that this alpha power lateralization reflects a spatial attention bias. Overall, our data support the contention that spatial shifts of attention contribute to deviant distraction.
2.
Hartmann, Thomas; Weisz, Nathan
An Introduction to the Objective Psychophysics Toolbox Journal Article
In: Frontiers in Psychology, vol. 11, 2020, ISSN: 1664-1078.
Abstract | Links | BibTeX | Tags: DATAPixx2, PROPixx
@article{hartmann_introduction_2020,
title = {An Introduction to the Objective Psychophysics Toolbox},
author = {Thomas Hartmann and Nathan Weisz},
url = {https://www.frontiersin.org/articles/10.3389/fpsyg.2020.585437},
issn = {1664-1078},
year = {2020},
date = {2020-01-01},
urldate = {2023-12-21},
journal = {Frontiers in Psychology},
volume = {11},
abstract = {The Psychophysics Toolbox (PTB) is one of the most popular toolboxes for the development of experimental paradigms. It is a very powerful library, providing low-level, platform independent access to the devices used in an experiment such as the graphics and the sound card. While this low-level design results in a high degree of flexibility and power, writing paradigms that interface the PTB directly might lead to code that is hard to read, maintain, reuse, and debug. Running an experiment in different facilities or organizations further requires it to work with various setups that differ in the availability of specialized hardware for response collection, triggering, and presentation of auditory stimuli. The Objective Psychophysics Toolbox (o_ptb) provides an intuitive, unified, and clear interface, built on top of the PTB that enables researchers to write readable, clean, and concise code. In addition to presenting the architecture of the o_ptb, the results of a timing accuracy test are presented. Exactly the same MATLAB code was run on two different systems, one of those using the VPixx system. Both systems showed sub-millisecond accuracy.},
keywords = {DATAPixx2, PROPixx},
pubstate = {published},
tppubtype = {article}
}
The Psychophysics Toolbox (PTB) is one of the most popular toolboxes for the development of experimental paradigms. It is a very powerful library, providing low-level, platform independent access to the devices used in an experiment such as the graphics and the sound card. While this low-level design results in a high degree of flexibility and power, writing paradigms that interface the PTB directly might lead to code that is hard to read, maintain, reuse, and debug. Running an experiment in different facilities or organizations further requires it to work with various setups that differ in the availability of specialized hardware for response collection, triggering, and presentation of auditory stimuli. The Objective Psychophysics Toolbox (o_ptb) provides an intuitive, unified, and clear interface, built on top of the PTB that enables researchers to write readable, clean, and concise code. In addition to presenting the architecture of the o_ptb, the results of a timing accuracy test are presented. Exactly the same MATLAB code was run on two different systems, one of those using the VPixx system. Both systems showed sub-millisecond accuracy.
3.
Hartmann, Thomas; Weisz, Nathan
Auditory cortical generators of the Frequency Following Response are modulated by intermodal attention Journal Article
In: NeuroImage, vol. 203, pp. 116185, 2019, ISSN: 1053-8119.
Abstract | Links | BibTeX | Tags: DATAPixx2, PROPixx, RESPONSEPixxMRI
@article{hartmann_auditory_2019,
title = {Auditory cortical generators of the Frequency Following Response are modulated by intermodal attention},
author = {Thomas Hartmann and Nathan Weisz},
url = {https://www.sciencedirect.com/science/article/pii/S1053811919307761},
doi = {10.1016/j.neuroimage.2019.116185},
issn = {1053-8119},
year = {2019},
date = {2019-12-01},
urldate = {2023-12-21},
journal = {NeuroImage},
volume = {203},
pages = {116185},
abstract = {The efferent auditory system suggests that brainstem auditory regions could also be sensitive to top-down processes. In electrophysiology, the Frequency Following Response (FFR) to speech stimuli has been used extensively to study brainstem areas. Despite seemingly straight-forward in addressing the issue of attentional modulations of brainstem regions by means of the FFR, the existing results are inconsistent. Moreover, the notion that the FFR exclusively represents subcortical generators has been challenged. We aimed to gain a more differentiated perspective on how the generators of the FFR are modulated by either attending to the visual or auditory input while neural activity was recorded using magnetoencephalography (MEG). In a first step our results confirm the strong contribution of also cortical regions to the FFR. Interestingly, of all regions exhibiting a measurable FFR response, only the right primary auditory cortex was significantly affected by intermodal attention. By showing a clear cortical contribution to the attentional FFR effect, our work significantly extends previous reports that focus on surface level recordings only. It underlines the importance of making a greater effort to disentangle the different contributing sources of the FFR and serves as a clear precaution of simplistically interpreting the FFR as brainstem response.},
keywords = {DATAPixx2, PROPixx, RESPONSEPixxMRI},
pubstate = {published},
tppubtype = {article}
}
The efferent auditory system suggests that brainstem auditory regions could also be sensitive to top-down processes. In electrophysiology, the Frequency Following Response (FFR) to speech stimuli has been used extensively to study brainstem areas. Despite seemingly straight-forward in addressing the issue of attentional modulations of brainstem regions by means of the FFR, the existing results are inconsistent. Moreover, the notion that the FFR exclusively represents subcortical generators has been challenged. We aimed to gain a more differentiated perspective on how the generators of the FFR are modulated by either attending to the visual or auditory input while neural activity was recorded using magnetoencephalography (MEG). In a first step our results confirm the strong contribution of also cortical regions to the FFR. Interestingly, of all regions exhibiting a measurable FFR response, only the right primary auditory cortex was significantly affected by intermodal attention. By showing a clear cortical contribution to the attentional FFR effect, our work significantly extends previous reports that focus on surface level recordings only. It underlines the importance of making a greater effort to disentangle the different contributing sources of the FFR and serves as a clear precaution of simplistically interpreting the FFR as brainstem response.
4.
Wang, Lupeng; Krauzlis, Richard J.
Visual Selective Attention in Mice Journal Article
In: Current Biology, vol. 28, no. 5, pp. 676–685.e4, 2018, ISSN: 0960-9822, (Publisher: Elsevier).
Links | BibTeX | Tags: DATAPixx2
@article{wang_visual_2018,
title = {Visual Selective Attention in Mice},
author = {Lupeng Wang and Richard J. Krauzlis},
url = {https://www.cell.com/current-biology/abstract/S0960-9822(18)30040-X},
doi = {10.1016/j.cub.2018.01.038},
issn = {0960-9822},
year = {2018},
date = {2018-03-01},
urldate = {2024-01-18},
journal = {Current Biology},
volume = {28},
number = {5},
pages = {676–685.e4},
note = {Publisher: Elsevier},
keywords = {DATAPixx2},
pubstate = {published},
tppubtype = {article}
}
5.
Alais, David; Leung, Johahn; der Burg, Erik Van
Linear Summation of Repulsive and Attractive Serial Dependencies: Orientation and Motion Dependencies Sum in Motion Perception Journal Article
In: Journal of Neuroscience, vol. 37, no. 16, pp. 4381–4390, 2017, ISSN: 0270-6474, 1529-2401, (Publisher: Society for Neuroscience Section: Research Articles).
Abstract | Links | BibTeX | Tags: DATAPixx2, PROPixx
@article{alais_linear_2017,
title = {Linear Summation of Repulsive and Attractive Serial Dependencies: Orientation and Motion Dependencies Sum in Motion Perception},
author = {David Alais and Johahn Leung and Erik Van der Burg},
url = {https://www.jneurosci.org/content/37/16/4381},
doi = {10.1523/JNEUROSCI.4601-15.2017},
issn = {0270-6474, 1529-2401},
year = {2017},
date = {2017-04-01},
urldate = {2023-12-21},
journal = {Journal of Neuroscience},
volume = {37},
number = {16},
pages = {4381–4390},
abstract = {Recent work from several groups has shown that perception of various visual attributes in human observers at a given moment is biased toward what was recently seen. This positive serial dependency is a kind of temporal averaging that exploits short-term correlations in visual scenes to reduce noise and stabilize perception. To date, this stabilizing “continuity field” has been demonstrated on stable visual attributes such as orientation and face identity, yet it would be counterproductive to apply it to dynamic attributes in which change sensitivity is needed. Here, we tested this using motion direction discrimination and predict a negative perceptual dependency: a contrastive relationship that enhances sensitivity to change. Surprisingly, our data showed a cubic-like pattern of dependencies with positive and negative components. By interleaving various stimulus combinations, we separated the components and isolated a positive perceptual dependency for motion and a negative dependency for orientation. A weighted linear sum of the separate dependencies described the original cubic pattern well. The positive dependency for motion shows an integrative perceptual effect and was unexpected, although it is consistent with work on motion priming. These findings suggest that a perception-stabilizing continuity field occurs pervasively, occurring even when it obscures sensitivity to dynamic stimuli.
SIGNIFICANCE STATEMENT Recent studies show that visual perception at a given moment is not entirely veridical, but rather biased toward recently seen stimuli: a positive serial dependency. This temporal smoothing process helps perceptual continuity by preserving stable aspects of the visual scene over time, yet, for dynamic stimuli, temporal smoothing would blur dynamics and reduce sensitivity to change. We tested whether this process is selective for stable attributes by examining dependencies in motion perception. We found a clear positive dependency for motion, suggesting that positive perceptual dependencies are pervasive. We also found a concurrent negative (contrastive) dependency for orientation. Both dependencies combined linearly to determine perception, showing that the brain can calculate contrastive and integrative dependencies simultaneously from recent stimulus history when making perceptual decisions.},
note = {Publisher: Society for Neuroscience
Section: Research Articles},
keywords = {DATAPixx2, PROPixx},
pubstate = {published},
tppubtype = {article}
}
Recent work from several groups has shown that perception of various visual attributes in human observers at a given moment is biased toward what was recently seen. This positive serial dependency is a kind of temporal averaging that exploits short-term correlations in visual scenes to reduce noise and stabilize perception. To date, this stabilizing “continuity field” has been demonstrated on stable visual attributes such as orientation and face identity, yet it would be counterproductive to apply it to dynamic attributes in which change sensitivity is needed. Here, we tested this using motion direction discrimination and predict a negative perceptual dependency: a contrastive relationship that enhances sensitivity to change. Surprisingly, our data showed a cubic-like pattern of dependencies with positive and negative components. By interleaving various stimulus combinations, we separated the components and isolated a positive perceptual dependency for motion and a negative dependency for orientation. A weighted linear sum of the separate dependencies described the original cubic pattern well. The positive dependency for motion shows an integrative perceptual effect and was unexpected, although it is consistent with work on motion priming. These findings suggest that a perception-stabilizing continuity field occurs pervasively, occurring even when it obscures sensitivity to dynamic stimuli.
SIGNIFICANCE STATEMENT Recent studies show that visual perception at a given moment is not entirely veridical, but rather biased toward recently seen stimuli: a positive serial dependency. This temporal smoothing process helps perceptual continuity by preserving stable aspects of the visual scene over time, yet, for dynamic stimuli, temporal smoothing would blur dynamics and reduce sensitivity to change. We tested whether this process is selective for stable attributes by examining dependencies in motion perception. We found a clear positive dependency for motion, suggesting that positive perceptual dependencies are pervasive. We also found a concurrent negative (contrastive) dependency for orientation. Both dependencies combined linearly to determine perception, showing that the brain can calculate contrastive and integrative dependencies simultaneously from recent stimulus history when making perceptual decisions.
SIGNIFICANCE STATEMENT Recent studies show that visual perception at a given moment is not entirely veridical, but rather biased toward recently seen stimuli: a positive serial dependency. This temporal smoothing process helps perceptual continuity by preserving stable aspects of the visual scene over time, yet, for dynamic stimuli, temporal smoothing would blur dynamics and reduce sensitivity to change. We tested whether this process is selective for stable attributes by examining dependencies in motion perception. We found a clear positive dependency for motion, suggesting that positive perceptual dependencies are pervasive. We also found a concurrent negative (contrastive) dependency for orientation. Both dependencies combined linearly to determine perception, showing that the brain can calculate contrastive and integrative dependencies simultaneously from recent stimulus history when making perceptual decisions.
6.
Alais, David; Locke, Shannon M.; Leung, Johahn; der Burg, Erik Van
No attentional capture from invisible flicker Journal Article
In: Scientific Reports, vol. 6, no. 1, pp. 29296, 2016, ISSN: 2045-2322, (Number: 1 Publisher: Nature Publishing Group).
Abstract | Links | BibTeX | Tags: DATAPixx2, PROPixx
@article{alais_no_2016,
title = {No attentional capture from invisible flicker},
author = {David Alais and Shannon M. Locke and Johahn Leung and Erik Van der Burg},
url = {https://www.nature.com/articles/srep29296},
doi = {10.1038/srep29296},
issn = {2045-2322},
year = {2016},
date = {2016-07-01},
urldate = {2024-01-12},
journal = {Scientific Reports},
volume = {6},
number = {1},
pages = {29296},
abstract = {We tested whether fast flicker can capture attention using eight flicker frequencies from 20–96 Hz, including several too high to be perceived (>50 Hz). Using a 480 Hz visual display rate, we presented smoothly sampled sinusoidal temporal modulations at: 20, 30, 40, 48, 60, 69, 80 and 96 Hz. We first established flicker detection rates for each frequency. Performance was at or near ceiling until 48 Hz and dropped sharply to chance level at 60 Hz and above. We then presented the same flickering stimuli as pre-cues in a visual search task containing five elements. Flicker location varied randomly and was therefore congruent with target location on 20% of trials. Comparing congruent and incongruent trials revealed a very strong congruency effect (faster search for cued targets) for all detectable frequencies (20–48 Hz) but no effect for faster flicker rates that were detected at chance. This pattern of results (obtained with brief flicker cues: 58 ms) was replicated for long flicker cues (1000 ms) intended to allow for entrainment to the flicker frequency. These results indicate that only visible flicker serves as an exogenous attentional cue and that flicker rates too high to be perceived are completely ineffective.},
note = {Number: 1
Publisher: Nature Publishing Group},
keywords = {DATAPixx2, PROPixx},
pubstate = {published},
tppubtype = {article}
}
We tested whether fast flicker can capture attention using eight flicker frequencies from 20–96 Hz, including several too high to be perceived (>50 Hz). Using a 480 Hz visual display rate, we presented smoothly sampled sinusoidal temporal modulations at: 20, 30, 40, 48, 60, 69, 80 and 96 Hz. We first established flicker detection rates for each frequency. Performance was at or near ceiling until 48 Hz and dropped sharply to chance level at 60 Hz and above. We then presented the same flickering stimuli as pre-cues in a visual search task containing five elements. Flicker location varied randomly and was therefore congruent with target location on 20% of trials. Comparing congruent and incongruent trials revealed a very strong congruency effect (faster search for cued targets) for all detectable frequencies (20–48 Hz) but no effect for faster flicker rates that were detected at chance. This pattern of results (obtained with brief flicker cues: 58 ms) was replicated for long flicker cues (1000 ms) intended to allow for entrainment to the flicker frequency. These results indicate that only visible flicker serves as an exogenous attentional cue and that flicker rates too high to be perceived are completely ineffective.