Modafinil, but not escitalopram, improves working memory and sustained attention in long-term, high-dose cocaine users.
OBJECTIVE
The purpose of the present study was to determine the effects of modafinil, escitalopram, and modafinil + escitalopram administration on neurocognition in a sample of long-term, high-dose cocaine users.


METHODS
Sixty-one cocaine-dependent individuals were randomly assigned to receive placebo (n = 14), modafinil, 200 mg, once daily (n = 16), escitalopram, 20 mg, once daily (n = 16), or modafinil and escitalopram, once daily (n = 15), for five days on an inpatient basis. Urinanalysis was used to confirm abstinence from cocaine on the day of admission and the next five days. Baseline neurocognitive assessment, which included measures of attention/information processing, episodic memory, and working memory, was conducted immediately after the washout phase and prior to the administration of modafinil. The follow-up assessment was conducted after participants had received modafinil or placebo for five days.


RESULTS
Repeated-measures, mixed model analysis of variance showed that modafinil administration was associated with significantly improved performance on two measures of working memory span (mean n-back span, maximum n-back span) and a trend toward significant improvement on a measure of visual working memory (visual accuracy) and two measures of sustained attention, consistency of response time (Variability) and reduced impulsivity (Perseveration). Modafinil administration did not modulate performance on measures of information processing speed or episodic memory. Escitalopram did not modulate performance on measures of cognition, either alone or in combination with modafinil.


CONCLUSIONS
This study provides initial data showing that, in a sample of long-term, high-dose cocaine users, administration of psychotropic medications, such as modafinil, can improve performance on measures of working memory. Moreover, it confirms the utility of studying the interactive effects of psychotropic medications to confirm the manner in which the candidate medications independently and interactively affect neurocognition. These effects are likely relevant in the treatment of cocaine dependence, in which the remediation of impaired working memory may be associated with improved treatment outcomes. This article is part of a Special Issue entitled 'Cognitive Enhancers'.
Baylor College of Medicine, Menninger Department of Psychiatry and Behavioral Sciences, 1977 Butler Blvd., Ste. E4.163, Houston, TX 77030, USA. ari.kalechstein@bcm.edu
A D
AD
Kalechstein
J J
JJ
Mahoney
J H
JH
Yoon
R
R
Bennett
R
R
De la Garza
D000328:Adult; D001741:Black or African American; D001559:Benzhydryl Compounds / Q000627:therapeutic use*; D015283:Citalopram / Q000627:therapeutic use; D019970:Cocaine-Related Disorders / Q000188:drug therapy* / Q000208:ethnology / Q000503:physiopathology; D003071:Cognition / Q000187:drug effects; D003072:Cognition Disorders / Q000209:etiology / Q000517:prevention & control*; D039721:Diagnostic and Statistical Manual of Mental Disorders; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D005500:Follow-Up Studies; D006787:Hospitals, Veterans; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000209:etiology / Q000517:prevention & control*; D008570:Memory, Short-Term / Q000187:drug effects; D008875:Middle Aged; D000077408:Modafinil; D018697:Nootropic Agents / Q000627:therapeutic use*; D011619:Psychotropic Drugs / Q000627:therapeutic use*; D017367:Selective Serotonin Reuptake Inhibitors / Q000627:therapeutic use; D013781:Texas
D001559:Benzhydryl Compounds; D015283:Citalopram; D000077408:Modafinil; D018697:Nootropic Agents; D011619:Psychotropic Drugs; D017367:Selective Serotonin Reuptake Inhibitors