A Study Of Binocular Rivalry In Patients With Depression

Objective: Binocular rivalry is an interesting phenomenon that exists in the field of vision. When different images are presented to each eye simultaneously, at a certain moment, one image is visible while the other is suppressed, and the next is the opposite. Perception alternates between the two stimuli at irregular intervals and the visual stimuli from both eyes were all striving for the dominant position. This separation between objective constant physical stimulus and subjective perception changes of visual physiology phenomenon called binocular rivalry. The neuroscientists are interested in what is the neural mechanisms of this separation change? Recently, the involvement of serotonin systems has been reported to be related to the phenomenon. Depression is a debilitating and highly recurrent chronic psychiatric disorder that has a lifetime prevalence of up to 20% in the community and typically characterized by sadness, despair, insomnia and low self-esteem. More importantly, severe depression can result in death and disability. An aberrant serotonin system has been hypothesized to play a crucial role in the pathogenesis of depression. Therefore, here we assessed the rivalry rate in patients with depression and aimed to explore whether perceptual rivalry was affected by a dysfunctional serotonin system in patients with depression and whether there was a rivalry rate difference between episode and remission states in depression patients.Materials and Methods: Twenty-eight patients with depression and 30 healthy controls were recruited in the study. We assessed the rivalry rate and the 17-item Hamilton Depression Rating Scale(HAMD) in patients with depression during clinical episode and remission states. The control participants also performed the task at two time points which are interval the same time with depression.Results:(1)The rivalry rates in patients with depression were significantly slower than in the controls(F = 23.779, df = 1, p <0.001).(2) The rivalry rates in ED were significantly slower than in RD(t=-5.406, p <0.001).(3)No significant differences in the rivalry rates between patients only receiving SSRIs and patients receiving SNRIs or SSRIs + NASSAs(F=0.302, df=1, p=0.588).(4)No significant correlation was observed between the changes in HAMD scores and those in the proportion of rivalry rates in patients with depression(r = 0.076,p = 0.701).Conclusions: Our findings demonstrate slow perceptual alternation rates in binocular rivalry in patients with depression and binocular rivalry rates in patients with depression during episodes were significantly slower than during remission in the same patients after regular antidepressant treatments. These results may provide further clues to serotonergic neural systems contribute to the dynamics of perception rivalry.