Dr. P. Andrews

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Curvature discrimination thresholds were measured for a wide range of stimulus curvatures and sizes. Results are compared with an ideal processor of curvature to provide relative efficiencies. The results lead to three major findings. (i) Curved lines may be processed with the same precision as straight lines for decisions of shape, demonstrating a new(More)
Sharpness and symmetry of orientation tuning were quantitatively investigated and compared in ninety-seven cells from areas 17 and 18 of the lightly-anaesthetised feline visual cortex. Halfwidths of orientation tuning at half-height ranged between 5 ° and 73 ° for long stimuli, with an extreme exception at 111 ° (excluding untuned cells). There was a(More)
1. Mesopic increment threshold spectral sensitivities of sixty-six on-centre and twenty-five off-centre ganglion cells in the cat were determined by recording from single fibres of the left optic tract at a level posterior to the optic chiasma.2. All units were monocularly driven; receptive fields were located almost exclusively in the right visual(More)
1. Responses of 122 on-centre or off-centre ganglion cells in cat to suprathreshold monochromatic stimulation have been analysed under mesopic adaptation with white light, recording from their single fibres in the optic tract at a level posterior to the chiasma. Fields described are monocularly driven, located in the right half-fields of either eye, and are(More)