Search

Objective: Acute administration of an antidepressant increases positive affective processing in healthy volunteers, an effect that may be relevant to the therapeutic actions of these medications. The authors investigated whether this effect is apparent in depressed patients early in treatment, prior to changes in mood and symptoms. Method: In a double-blind, placebo-controlled, between-groups randomized design, the authors examined the effect of a single 4-mg dose of the norepinephrine reuptake inhibitor reboxetine on emotional processing. Thirty-three depressed patients were recruited through primary care clinics and the community and matched to 31 healthy comparison subjects. Three hours after dosing, participants were given a battery of emotional processing tasks comprising facial expression recognition, emotional categorization, and memory. Ratings of mood, anxiety, and side effects were also obtained before and after treatment. Results: Depressed patients who received placebo showed reduced recognition of positive facial expressions, decreased speed in responding to positive self-relevant personality adjectives, and reduced memory for this positive information compared to healthy volunteers receiving placebo. However, this effect was reversed in patients who received a single dose of reboxetine, despite the absence of changes in subjective ratings of mood or anxiety. Conclusions: Antidepressant drug administration modulates emotional processing in depressed patients very early in treatment, before changes occur in mood and symptoms. This effect may ameliorate the negative biases in information processing that characterize mood and anxiety disorders. It also suggests a mechanism of action compatible with cognitive theories of depression. [ABSTRACT FROM AUTHOR]

Objective: Antidepressants that inhibit the reuptake of serotonin (SSRI5) or nor- epinephrine (SNRIs) are effective in the treatment of disorders such as depression and anxiety. Cognitive psychological theories emphasize the importance of correcting negative biases of information processing in the nonpharmacological treatment of these disorders, but it is not known whether antidepressant drugs can directly modulate the neural processing of affective information. The present study therefore assessed the actions of repeated antidepressant administration on perception and memory for positive and negative emotional information in healthy volunteers. Method: Forty-two male and female volunteers were randomly assigned to 7 days of double-blind intervention with the SSRI citalopram (20 mg/day), the SNRI reboxetine (8 mg/day), or placebo. On the final day, facial expression recognition, emotion-potentiated startle response, and memory for affect-laden words were assessed. Questionnaires monitoring mood, hostility, and anxiety were given before and after treatment. Results: In the facial expression recognition task, citalopram and reboxetine reduced the identification of the negative facial expressions of anger and fear. Citalopram also abolished the increased startle response found in the context of negative affective images. Both antidepressants increased the relative recall of positive (versus negative) emotional material. These changes in emotional processing occurred in the absence of significant differences in ratings of mood and anxiety. However, reboxetine decreased subjective ratings of hostility and elevated energy Conclusions: Short-term administration of two different antidepressant types had similar effects on emotion-related tasks in healthy volunteers, reducing the processing of negative relative to positive emotional material. Such effects of antidepresants may ameliorate the negative biases in information processing that characterize mood and anxiety disorders. They also suggest a mechanism of action potentially compatible with cognitive theories of anxiety and depression. [ABSTRACT FROM AUTHOR]