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Human single-neuron responses at the threshold of conscious recognition.

ABSTRACT: We studied the responses of single neurons in the human medial temporal lobe while subjects viewed familiar faces, animals, and landmarks. By progressively shortening the duration of stimulus presentation, coupled with backward masking, we show two striking properties of these neurons. (i) Their responses are not statistically different for the 33-ms, 66-ms, and 132-ms stimulus durations, and only for the 264-ms presentations there is a significantly higher firing. (ii) These responses follow conscious perception, as indicated by the subjects' recognition report. Remarkably, when recognized, a single snapshot as brief as 33 ms was sufficient to trigger strong single-unit responses far outlasting stimulus presentation. These results suggest that neurons in the medial temporal lobe can reflect conscious recognition by "all-or-none" responses.

SUBMITTER: Quiroga RQ

PROVIDER: S-EPMC2265174 | biostudies-literature | 2008 Mar

REPOSITORIES: biostudies-literature

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Human single-neuron responses at the threshold of conscious recognition.

Quiroga R Quian RQ Mukamel R R Isham E A EA Malach R R Fried I I

Proceedings of the National Academy of Sciences of the United States of America 20080225 9

We studied the responses of single neurons in the human medial temporal lobe while subjects viewed familiar faces, animals, and landmarks. By progressively shortening the duration of stimulus presentation, coupled with backward masking, we show two striking properties of these neurons. (i) Their responses are not statistically different for the 33-ms, 66-ms, and 132-ms stimulus durations, and only for the 264-ms presentations there is a significantly higher firing. (ii) These responses follow co ...[more]

PMID: 18299568

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