title: Unequal representation of cardinal and oblique contours in ferret visual cortex.
abstract: We have measured the amount of cortical space activated by differently oriented gratings in 25 adult ferrets by optical imaging of intrinsic signal. On average, 7% more area of the exposed visual cortex was preferentially activated by vertical and horizontal contours than by contours at oblique angles. This anisotropy may reflect the real-world prevalence of contours in the cardinal axes and could explain the greater sensitivity of many animals to vertical and horizontal stimuli.
authors.affiliation: Department of Neurobiology, Box 3209, Duke University Medical Center, Durham, NC 27710, USA.
authors.forename: D M
authors.initials: DM
authors.lastname: Coppola
authors.forename: L E
authors.initials: LE
authors.lastname: White
authors.forename: D
authors.initials: D
authors.lastname: Fitzpatrick
authors.forename: D
authors.initials: D
authors.lastname: Purves
mesh_terms: D000818:Animals; D001931:Brain Mapping; D005289:Ferrets; D009949:Orientation; D010775:Photic Stimulation; D014793:Visual Cortex / Q000502:physiology*; D014796:Visual Perception