Visual discomfort: the influence of spatial frequency.
The response of different visual discomfort groups to a range of spatial frequencies at threshold and suprathreshold was investigated. In experiment 1, a paired-comparison task was conducted. The high visual discomfort group judged a spatial frequency of 4 cycles deg-1 as the most perceptually distorted and somatically unpleasant to view. The moderate and low visual discomfort groups judged 8 and 12 cycles deg-1 as more perceptually and somatically unpleasant to view than lower spatial frequencies. In experiment 2, the spatial contrast-sensitivity function (CSF) for the high visual discomfort group was depressed for spatial frequencies between 1 and 12 cycles deg-1 in comparison with the moderate and low visual discomfort groups. When these same spatial frequencies were modulated at 6 Hz, CSFs were the same for all groups. These results are discussed in relation to a failure of inhibition across spatial-frequency channels in the high visual discomfort group. This may be explained by a more generalised parvocellular system processing deficit. Possible similarities between some forms of migraine and visual discomfort are highlighted.
Conlon
E
E
School of Applied Psychology, Griffith University, PMB 50 Gold Coast Mail Centre, QLD 9726, Australia. e.conlon@mailbox.gu.edu.au
Lovegrove
W
W
Barker
S
S
Chekaluk
E
E
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D015350:Contrast Sensitivity / Q000502:physiology; D006801:Humans; D008029:Lighting; D008881:Migraine Disorders / Q000503:physiopathology; D009433:Neural Inhibition / Q000502:physiology; D010469:Perceptual Distortion / Q000502:physiology*; D012044:Regression Analysis; D014796:Visual Perception / Q000502:physiology*