The relationship between feline pupil size and luminance

  title={The relationship between feline pupil size and luminance},
  author={Peter Hammond and G. S. V. Mouat},
  journal={Experimental Brain Research},
SummaryThe relationships between luminance and height, width or area of the feline pupil were investigated in awake, normal adult cats whose pupils were photographed over a range of light levels with the aid of electronic flash. The results are compared with previous measurements of pupil width and height in awake animals (Kappauf 1943); and with estimates of pupil width, height and area in lightly-anaesthetised cats (Wilcox and Barlow 1975). The implications of these results for retinal… 

Mechanistic modeling of vertebrate spatial contrast sensitivity and acuity at low luminance

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A mechanistic inter-species comparison of flicker sensitivity

X and Y ganglion cells inform the cat's brain about contrast in the retinal image

The results indicate strongly that X and Y cells inform the cat's brain about contrast in the retinal image when nonoptimal spatial frequencies were used as stimuli.

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This thesis has been the product of three projects which are all related to depth perception, within the core discipline of vision science. The first project was collaborative work between the



The size and shape of the pupil in lightly anaesthetized cats as a function of luminance

The Purkinje shift in cat: extent of the mesopic range

The technique employed involves measurement of the relative shift in threshold with adaptation level, between two wave‐lengths respectively selective for cones and rods at threshold, which compares with that predicted from the Dartnall nomogram for visual pigments 556 and 507.


The size and shape of rod and cone centres of cat retinal ganglion cells

  • B. Ahmed
  • Biology
    Experimental Brain Research
  • 2004
SummaryReceptive field centres of cat retinal ganglion cells, as mediated by rod and by cone inputs, were mapped as contours of iso-sensitivity at a mid-mesopic adapting luminance using,

Photoreceptor inputs to cat lateral geniculate nucleus cells

  • G. Mouat
  • Biology
    Experimental Brain Research
  • 2004
The spectral sensitivities of single on- and off-centre, brisk sustained and brisk transient cells recorded from the A laminae of the lateral geniculate nucleus (LGNd) in cats anaesthetised with nitrous oxide and oxygen supplemented with halothane are interpreted as suggesting that the cells of the LGNd receive inputs from rods with maximum sensitivity at 507 nm and a single class of cones maximally sensitive at 556 nm.

Suprathreshold spectral properties of single optic tract fibres in cat, under mesopic adaptation; cone—rod interaction

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

Receptive field mechanisms of sustained and transient retinal ganglion cells in the cat

Receptive field organization in lightly pentobarbitone-anaesthetised cats was investigated, suggesting that the surround mechanism in sustained cells is spatially more extensive than the centre mechanism but does not extend entirely through the centre of the field.

Cat colour vision: evidence for more than one cone process

1. The ability of cats to distinguish colours was investigated at mesopic and photopic levels to test the hypothesis that cats discriminate wavelength by using rods in conjunction with a single type