QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

The Journal of Neuroscience, September 23, 2009, 29(38):11753-11760; doi:10.1523/JNEUROSCI.1991-09.2009

This Article Full Text Full Text (PDF) Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Yeh, C.-I Articles by Shapley, R. M. PubMed PubMed Citation Articles by Yeh, C.-I Articles by Shapley, R. M.

 Previous Article  |  Next Article 

Behavioral/Systems/Cognitive
"Black" Responses Dominate Macaque Primary Visual Cortex V1

Chun-I Yeh, ^* Dajun Xing, ^* and Robert M. Shapley

Center for Neural Science, New York University, New York, New York 10036

Correspondence should be addressed to Dr. Chun-I Yeh, Center for Neural Science, New York University, 4 Washington Place, New York, NY 10003. Email: ciy{at}cns.nyu.edu

Achromatic visual information is transferred from the retina to the brain through two parallel channels: ON-center cells carry "white" information and OFF-center cells "black" information (Nelson et al., 1978; Schiller, 1982; Schiller et al., 1986). Responses of ON and OFF retinal and thalamic neurons are approximately equal in magnitude (Krüger and Fischer, 1975; Kremers et al., 1993), but psychophysical studies have shown that humans detect light decrements (black) better and faster than increments (white) (Blackwell, 1946; Short, 1966; Krauskopf, 1980; Whittle, 1986; Bowen et al., 1989; Chan and Tyler, 1992; Kontsevich and Tyler, 1999; Chubb and Nam, 2000; Dannemiller and Stephens, 2001). From recordings of single-cell activity in the macaque monkey's primary visual cortex (V1), we found that black-dominant neurons substantially outnumbered white-dominant neurons in the corticocortical output layers 2/3, but the numbers of black- and white-dominant neurons were nearly equal in the thalamocortical input layer 4c. These results strongly suggest that the black-over-white preference is generated or greatly amplified in V1. The predominance of OFF neurons in layers 2/3 of V1, which provide visual input to higher cortical areas, may explain why human subjects detect black more easily than white. Furthermore, our results agree with human EEG and fMRI findings that V1 responses to decrements are stronger than to increments, though the OFF/ON imbalance we found in layers 2/3 of macaque V1 is much larger than in the whole V1 population in the human V1 experiments (Zemon et al., 1988, 1995; Olman et al., 2008).

---

Received April 27, 2009; revised June 25, 2009; accepted Aug. 7, 2009.

Correspondence should be addressed to Dr. Chun-I Yeh, Center for Neural Science, New York University, 4 Washington Place, New York, NY 10003. Email: ciy{at}cns.nyu.edu

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help