RT Journal Article SR Electronic T1 Enhanced Visual Motion Perception in Major Depressive Disorder JF The Journal of Neuroscience JO J. Neurosci. FD Society for Neuroscience SP 9072 OP 9077 DO 10.1523/JNEUROSCI.1003-09.2009 VO 29 IS 28 A1 Julie D. Golomb A1 Jenika R. B. McDavitt A1 Barbara M. Ruf A1 Jason I. Chen A1 Aybala Saricicek A1 Kathleen H. Maloney A1 Jian Hu A1 Marvin M. Chun A1 Zubin Bhagwagar YR 2009 UL http://www.jneurosci.org/content/29/28/9072.abstract AB Major depressive disorder (MDD) is a mood disorder that is not traditionally considered to affect the visual system. However, recent findings have reported decreased cortical levels of the inhibitory neurotransmitter GABA in occipital cortex. To explore possible functional consequences of MDD on visual processing, we applied a psychophysical visual motion processing task in which healthy young adults typically exhibit impaired perceptual discrimination of large high-contrast stimuli. It has been suggested that this phenomenon, spatial suppression, is mediated by GABAergic center–surround antagonism in visual pathways. Based on previous findings linking MDD to occipital GABA dysfunction, we hypothesized that MDD patients would exhibit decreased spatial suppression, leading to the counterintuitive hypothesis of better psychophysical performance. Indeed, motion perception for typically suppressed stimuli was enhanced in patients with MDD compared with age-matched controls. Furthermore, the degree of spatial suppression correlated with an individual's illness load; patients with greater lifetime duration of depression exhibited the least spatial suppression and performed the best in the high-contrast motion discrimination task. Notably, this decrease in spatial suppression persisted beyond recovery and without the confound of acute illness or treatment; all patients had been clinically recovered and unmedicated for several months at the time of testing, suggesting that depression has ubiquitous consequences that may persist long after mood symptoms have receded. This finding raises the possibility that spatial suppression may represent a sensitive endophenotypic marker of trait vulnerability in MDD.