PSYB51H3 Chapter Notes -Retinal Ganglion Cell, Visual Acuity, Receptive Field
Document Summary
Chapter 3: spatial vision from stars to stripes. Sine wave gratings: a grating with a sinusoidal luminance profile misperception of a grating due to undersampling. Acuity for low-contrast stripes: number of cycles of a grating per unit of visual angle. Although pure swg maybe rare in real world, patterns of stripes w/ more or less fuzzy boundaries are quite common (trees in forests, books on bookshelves) Visual system appears to break down real-world images into vast number of components essentially a swg with a particular spatial frequency. Phase: matches its receptive field size relative position of a grating. Important features of the visual cortex: topographical mapping, dramatic scaling of info. Coritcal magnification: specific region (eg: 1 degree) in the visual field amount of cortical area (usually in mm) devoted to: imp. Consequence visual acuity declines in an orderly fashion with eccentricity. Hubel + wiesel: cat experiement: most fundamental discovery: neurons in striate cortex respond to stripes not stars.
