Human Intracranial recordings link suppressed transients rather than 'filling-in' to perceptual continuity across blinks
- The Hebrew University of Jerusalem, Israel
- New York University, United States
- Weizmann Institute of Science, Israel
- Hofstra Northwell School of Medicine, United States
- Columbia University College of Physicians and Surgeons, United States
- The Weizmann Institute of Science, Israel
Abstract
We hardly notice our eye blinks, yet an externally generated retinal interruption of a similar duration is perceptually salient. We examined the neural correlates of this perceptual distinction using intracranially measured ECoG signals from human visual cortex in 14 patients. In early visual areas (V1 and V2), the disappearance of the stimulus due to either invisible blinks or salient blank video frames ('gaps') led to a similar drop in activity level, followed by a positive overshoot beyond baseline, triggered by stimulus reappearance. Ascending the visual hierarchy, the reappearance-related overshoot gradually subsided for blinks but not for gaps. By contrast, the disappearance-related drop did not follow the perceptual distinction - it was actually slightly more pronounced for blinks than for gaps. These findings suggest that blinks' limited visibility compared with gaps is correlated with suppression of blink-related visual activity transients, rather than with 'filling-in' of the occluded content during blinks.
Article and author information
Author details
Funding
Helen and Martin Kimmel Award (7204760501)
- Rafael Malach
Israel Science Foundation (I-CORE, 7111000508)
- Rafael Malach
United States-Israel Binational Science Foundation (2013070)
- Leon Y Deouell
Israel Science Foundation (1902_14)
- Leon Y Deouell
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: All patients gave fully informed consent, including consent to publish, according to NIH guidelines, as monitored by the institutional review board at the Feinstein Institute for Medical Research, in accordance with the Declaration of Helsinki. Data was obtained as part of protocol number 07-125. Patients had the opportunity to consent prior to electrode implantation and were informed that they may choose to decline or later withdraw from the study without affecting their clinical care. Consent includes agreement to participate with studies of cognitive and sensorimotor processes and publication of any deidentified data obtained. Risks include tedium and potential breach of medical information and are minimized by giving ample breaks and implementation of protocols to deidentify data close to the time of recording. Benefits to the subject include increased monitoring of the electrocorticogram and involvement of research methods to help localize electrodes with respect to preoperative MRI.
Copyright
© 2016, Golan et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Human Intracranial recordings link suppressed transients rather than 'filling-in' to perceptual continuity across blinks
eLife 5:e17243.
https://doi.org/10.7554/eLife.17243
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