Cortical potentials evoked by short wavelength patterned light.
Pattern-evoked cortical potentials (PECPs) were recorded in response to the onset of blue and black, square wave gratings superimposed on a bright orange background. Several lines of evidence, including spectral sensitivity and the absence of response in a tritanopic subject, indicate that the measured cortical potentials reflect input from S cones. Spatial and temporal tuning of this response are comparable to psychophysical measures of the S-pathway. In agreement with previous studies of achromatic and chromatic spatial processing, a comparison of the response to patterns of different complexity indicates that spatial processing in the S-pathway can be described by linear systems analysis. An oblique effect for the S-pathway is demonstrated. Additional findings which bear on the nature of postreceptoral processing in the S-pathway are considered. Included are measurements from a patient with diabetic retinopathy. This study underscores the potential importance of the S-pathway for spatial information processing.
Rabin
J
J
School of Optometry, University of California, Berkeley.
Adams
A J
AJ
D000328:Adult; D000550:Amblyopia / Q000503:physiopathology; D003930:Diabetic Retinopathy / Q000503:physiopathology; D005074:Evoked Potentials, Visual / Q000502:physiology*; D006801:Humans; D008027:Light; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010786:Photoreceptor Cells / Q000502:physiology; D011601:Psychophysics; D014793:Visual Cortex / Q000502:physiology* / Q000503:physiopathology; D014795:Visual Pathways / Q000502:physiology; D014796:Visual Perception / Q000502:physiology