Abstract
Purpose :
Sensory dominance occurs when there is perceptual dominance of one eye over the other, amblyopes usually expressed extreme sensory eye dominance, information from the amblyopic eye (commonly non-dominated eye) is regularly suppressed, which showed larger response variability and louder random internal noise. However, most normal individuals also exhibited strong sensory eye dominance, but we still had no idea about the difference of random noise and distribution in response variance in normal group. So we evaluated the distribution of response time and signal-noise-ratio using a new interocular suppression technique, to see the difference in distribution of response consistency between the sensory dominant eye and the non-dominant eye in ordinary people.
Methods :
Ocular dominance was evaluated with continuous flash technique. The tested eye viewed a Gabor patch signal with increasing contrast, starting from 0%, and the other eye viewed a Mondrian noise with decreasing contrast, starting from 100%, at 1% per 100ms. The time needed to detect the Gabor patch in the noise was recorded (Tbreak) for each eye, CV of Tbreak was also calculated as subjects’ response variance. The log ratio of Mondrian to Gabor’s contrasts(SNR) at the moment of detection was computed. T-test was used to compare 50 SNR values collected for each eye. A p value<0.05 was regarded as having unbalanced eyes, the eye with lower SNR was dominant eye. Exp-Gauss model was used to fit distribution of SNR for each subject.
Results :
112 subjects with two balanced eyes and 174 subjects with two unbalanced eyes were included. The mean Tbreak in balance group was 5.98±1.56s, which was significantly different from Tbreak in unbalance group (5.12±1.71s in dominant eyes and 6.83±1.65s in non-dominant eyes respectively, one-way ANOVA, p<0.01). CV of balance group was 0.30±0.14, which was significantly higher than CV of non-dominant eyes in unbalance group (0.24±0.12,one-way ANOVA, p<0.01). For SNR values in unbalance group, when fitted by Exp-Gauss model, tau values was significantly higher in non-dominant eyes than dominant eyes（paired sample T-test，p<0.01）, but tau values in balance group showed no significant difference(p=0.67).
Conclusions :
Subjects in balance group showed consistent response distributions between two eyes. However, for subjects in unbalance group, although the sensory dominant eye needed shorter Tbreak time, the dominant eye showed higher response variance.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.