Differences in the neural basis of human amblyopia: the distribution of the anomaly across the visual field.
Spatio-temporal contrast sensitivities to horizontally-oriented Gaussian-weighted patches of sinusoidal grating stimuli were determined across the nasal and temporal visual fields of strabismic and non-strabismic, anisometropic amblyopes. The visual field distribution of the amblyopic anomaly differs in strabismic and non-strabismic, anisometropic eyes. In strabismus the peripheral region of one or both hemifields is spared; in non-strabismic, anisometropic cases the loss is evenly distributed across the binocular visual field but is not present in the monocular temporal field. These findings suggest that the non-strabismic forms of amblyopia in humans result from binocular competitive imbalance in early life. The strabismic results pose two problems for the present competitive model of amblyopia: in strabismus, amblyopia is mainly limited to central vision and shows an asymmetric distribution.
D000293:Adolescent; D000328:Adult; D000550:Amblyopia / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D010364:Pattern Recognition, Visual / Q000502:physiology; D012030:Refractive Errors / Q000503:physiopathology; D012684:Sensory Thresholds / Q000502:physiology; D013285:Strabismus / Q000503:physiopathology; D014792:Visual Acuity; D014794:Visual Fields