Alertness and visuospatial attention in clinical depression

BACKGROUND: Cognitive deficits are a substantial burden in clinical depression. The present study considered dysfunction in the right-hemispheric attention network in depression, examining alertness and visuospatial attention. METHODS: Three computerized visuospatial attention tests and an alertness test were administered to 16 depressive patients and 16 matched healthy controls. RESULTS: Although no significant group effect was observed, alertness predicted reduced visuospatial performance in the left hemifield. Furthermore, sad mood showed a trend towards predicting left visual field omissions. CONCLUSIONS: Decreased alertness may lead to lower left hemifield visuospatial attention; this mechanism may be responsible for a spatial bias to the right side in depression, even though treatment of depression and anxiety may reduce this cognitive deficit.