Short Term Antidepressant Administration Reduces Negative Self-referential Processing in the Medial Prefrontal Cortex in Subjects at Risk for Depression

Martina Di Simplicio (1) , Raymond Norbury (1) , Catherine Harmer (1)

1 Psychiatry

Depression has been associated with changes in responses within the medial prefrontal (mPFC) cortex during emotional information processing. Antidepressant drug treatment has been shown to modify neural responses in healthy volunteers early in treatment within similar circuitry. However it is unclear whether the same early effect occurs in depressed patients, prior to changes in mood. The current study therefore investigated the effects of 7 days administration of the SSRI citalopram versus placebo in volunteers (n=29) at high risk for the development of depression using the personality phenotype of high neuroticism in a double-blind, between-groups design. On the last day of treatment resting haemoperfusion and functional MRI data were acquired during a self-referential words categorization task. A significant activation in a cluster of mPFC areas, including dorsal Anterior Cingulate and right Orbitofrontal Cortex was revealed, driven by decreased responses to negative self-descriptors following citalopram compared to placebo, in the absence of any mood differences. These findings show a normalization of neural abnormalities in a population at risk early in treatment, supporting the theory that antidepressants may indeed act by modifying specific neural dysfunctions correlated to negative cognitive biases.

Mots clés: depression; SSRI; emotion; neuroticism; prefrontal cortex

Martina Di Simplicio, Raymond Norbury, Catherine Harmer. Short Term Antidepressant Administration Reduces Negative Self-referential Processing in the Medial Prefrontal Cortex in Subjects at Risk for Depression. Molecular Psychiatry, 2011, ⟨10.1038/mp.2011.16⟩. ⟨hal-00618172⟩