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Psychopharmacology

, Volume 185, Issue 3, pp 339–347 | Cite as

The effects of escitalopram on working memory and brain activity in healthy adults during performance of the n-back task

  • Emma J. Rose
  • Enrico Simonotto
  • Edgar P. Spencer
  • Klaus P. EbmeierEmail author
Original Investigation

Abstract

Rationale

Psychotropic medication affects cognition and brain function, making it a potential confounder in functional neuroimaging studies of psychiatric patients.

Objective

To determine whether the sub-acute administration of an antidepressant (escitalopram) would induce differences in cognitive performance and associated brain function, which could be observed within the normal power of a functional imaging study.

Materials and methods

Healthy adults (N=10) received a short course of escitalopram (10 mg/day for 7 days). Participants performed a parametric working memory (WM) task during BOLD fMRI, both while medication-free and after medication. To control for order effects, the medication-free examination was completed by half the subjects before starting medication and by the other half at least one week after medication.

Results

Escitalopram had no significant effect on WM accuracy or reaction time. Preliminary analysis of the imaging data revealed no significant (p corrected<0.05) differences in memory-load-dependent activation between conditions. However, small volume correction analysis of regions that were significant prior to correction for multiple comparisons highlighted between condition differences in regions likely to be susceptible to antidepressant effects (i.e. thalamus, anterior cingulate and inferior frontal gyrus).

Conclusions

These results suggest that the sub-acute administration of antidepressants in healthy controls does not affect cognitive or hemodynamic function in healthy adults to a magnitude greater than one standard deviation unit. Therefore, the confounding effect of antidepressants on signal intensity in imaging studies of medicated, depressed individuals may be limited.

Keywords

Escitalopram Working memory Major depression Functional MRI 

Notes

Acknowledgements

This work was funded in part by a research studentship from the Medical Research Council (EJR), by a SHEFC Research Development Grant (KPE) and funds from the Gordon Small Charitable Trust (KPE). None of the authors declares an interest that may bias the results presented.

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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Emma J. Rose
    • 1
    • 2
    • 3
  • Enrico Simonotto
    • 1
    • 2
  • Edgar P. Spencer
    • 4
  • Klaus P. Ebmeier
    • 1
    • 2
    Email author
  1. 1.Department of PsychiatryUniversity of EdinburghEdinburghUK
  2. 2.SHEFC Brain Imaging Research Centre for Scotland, Department of Clinical NeurosciencesWestern General HospitalEdinburghUK
  3. 3.Intramural Research ProgrammeNational Institute on Drug AbuseBaltimoreUSA
  4. 4.Medical Toxicology UnitGuys’ and Saint Thomas’ HospitalLondonUK

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