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Acute fluoxetine modulates emotional processing in young adult volunteers

Published online by Cambridge University Press:  13 April 2015

L. P. Capitão ,
S. E. Murphy ,
M. Browning ,
P. J. Cowen  and
C. J. Harmer
L. P. Capitão*
Affiliation:
University Department of Psychiatry, Warneford Hospital, Oxford, UK
S. E. Murphy
Affiliation:
University Department of Psychiatry, Warneford Hospital, Oxford, UK
M. Browning
Affiliation:
University Department of Psychiatry, Warneford Hospital, Oxford, UK
P. J. Cowen
Affiliation:
University Department of Psychiatry, Warneford Hospital, Oxford, UK
C. J. Harmer
Affiliation:
University Department of Psychiatry, Warneford Hospital, Oxford, UK
*
* Address for correspondence: L. P. Capitão, Oxford University Department of Psychiatry, Warneford Hospital, Oxford OX3 7JX, UK. (Email: [email protected])
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Abstract

Background

Fluoxetine is generally regarded as the first-line pharmacological treatment for young people, as it is believed to show a more favourable benefit:risk ratio than other antidepressants. However, the mechanisms through which fluoxetine influences symptoms in youth have been little investigated. This study examined whether acute administration of fluoxetine in a sample of young healthy adults altered the processing of affective information, including positive, sad and anger cues.

Method

A total of 35 male and female volunteers aged between 18 and 21 years old were randomized to receive a single 20 mg dose of fluoxetine or placebo. At 6 h after administration, participants completed a facial expression recognition task, an emotion-potentiated startle task, an attentional dot-probe task and the Rapid Serial Visual Presentation. Subjective ratings of mood, anxiety and side effects were also taken pre- and post-fluoxetine/placebo administration.

Results

Relative to placebo-treated participants, participants receiving fluoxetine were less accurate at identifying anger and sadness and did not show the emotion-potentiated startle effect. There were no overall significant effects of fluoxetine on subjective ratings of mood.

Conclusions

Fluoxetine can modulate emotional processing after a single dose in young adults. This pattern of effects suggests a potential cognitive mechanism for the greater benefit:risk ratio of fluoxetine in adolescent patients.

Keywords

Adolescent depressionanger processingantidepressantsanxietyfluoxetineselective serotonin reuptake inhibitors
Type
Original Articles
Information
Psychological Medicine , Volume 45 , Issue 11 , August 2015 , pp. 2295 - 2308
Copyright
Copyright © Cambridge University Press 2015 

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