PT  - JOURNAL ARTICLE
AU  - Julie D. Golomb
AU  - Jenika R. B. McDavitt
AU  - Barbara M. Ruf
AU  - Jason I. Chen
AU  - Aybala Saricicek
AU  - Kathleen H. Maloney
AU  - Jian Hu
AU  - Marvin M. Chun
AU  - Zubin Bhagwagar
TI  - Enhanced Visual Motion Perception in Major Depressive Disorder
AID  - 10.1523/JNEUROSCI.1003-09.2009
DP  - 2009 Jul 15
TA  - The Journal of Neuroscience
PG  - 9072--9077
VI  - 29
IP  - 28
4099  - http://www.jneurosci.org/content/29/28/9072.short
4100  - http://www.jneurosci.org/content/29/28/9072.full
SO  - J. Neurosci.2009 Jul 15; 29
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.