Details

Autor(en) / Beteiligte

• Sirovich, Lawrence
• Uglesich, Robert
• McLaughlin, David W.

Titel

The Organization of Orientation and Spatial Frequency in Primary Visual Cortex

Ist Teil von

• Proceedings of the National Academy of Sciences - PNAS, 2004-11, Vol.101 (48), p.16941-16946

Ort / Verlag

United States: National Academy of Sciences

Erscheinungsjahr

2004

Quelle

MEDLINE

Beschreibungen/Notizen

• Many studies have demonstrated that the primary visual cortex contains multiple functional maps of visual properties (e.g., ocular dominance, orientation preference, and spatial-frequency preference), but as yet no consistent picture has emerged as to how these maps are related to one another. Three divergent, prior optical-imaging studies of spatial frequency are reanalyzed and critiqued in this article. Evidence is presented that a nonstimulus-specific response biased the interpretation of results in previous studies. In addition to reexamining four prior cat experiments, we carried out one new experiment. Through the use of different methods and a careful removal of the nonspecific response, we are led in all instances to a unique view of cortical organization for spatial-frequency preference. In particular, we find little apparent evidence for a columnar organization for spatial frequency. The response recorded by each image pixel may be viewed as arising from an admixture of low- and high-spatial-frequency populations. For most pixels, the ratio of these populations is 1:1.