Galantamine Effects on Cognitive Function in Abstinent Cocaine Users

Rapid Visual Processing test (RVIP) is a measure of sustained attention with a small working memory component that is sensitive to cholinergic enhancers. In the RVIP, subjects must detect either odd or even 3 digit sequences appearing in a box in a pseudo-random order at 100 digits per minute. Reaction time (RT) to correct answers, total hits, correct rejections and A' (sensitivity to target sequences) were determined. Paired Associate Learning (PAL) measures visual memory and new learning by testing a the ability to remember the initial location of a pattern after it is re-presented in the middle of the screen. Errors result in a reminder presentation of the original location. The stages completed and number of errors are measures of interest. Pattern Recognition Memory (PRM) tests visual pattern recognition memory in a two choice forced discrimination paradigm. 12 visual patterns are presented, then the subject must choose between each of these patterns and a novel pattern.

The SART is a Go / NoGo task measuring the ability to activate or inhibit responses. Cocaine users are know to have deficits in response inhibition on such tasks. The number of errors on NoGo and Go trials, as well as the mean reaction time (RT in milliseconds) for correct responses on Go Trials were measured. Complete data for 3 subjects in the Placebo group, and for 1 subject in the galantamine group were not capture do to experimenter and computer errors.

The Cocaine-Stroop task measures attention capture (attentional bias) secondary to cocaine cues; (Stroop effect - calculated as the difference between mean RT on cocaine words and mean RT on control words). Subjects completed 2 counterbalanced blocks (150 trials per block). One block contained 15 cocaine words and neutral words in a mixed order. The other block contained 15 control words matched in length and frequency to cocaine words, and a different set of neutral words. Subjects were required to indicate the colors in which the words were written as quickly and accurately as possible. Reaction times for identification of word color was measured. In addition, the difference in RT to words following cocaine and control words were measured (carry-over effect). Complete data for 3 participants (2 placebo and 1 galantamine) were not capture due to experimenter and computer errors.