Development and Initial Validation of the Perceptual Assessment of Memory (PASSOM): A Simulator Study.

OBJECTIVE: Performance validity tests (PVTs) are an integral component of neuropsychological assessment. There is a need for the development of more PVTs, especially those employing covert determinations. The aim of the present study was to provide initial validation of a new computerized PVT, the Perceptual Assessment of Memory (PASSOM). METHOD: Participants were 58 undergraduate students randomly assigned to a simulator (SIM) or control (CON) group. All participants were provided written instructions for their role prior to testing and were administered the PASSOM as part of a brief battery of neurocognitive tests. Indices of interest included response accuracy for Trials 1 and 2, and total errors across Trials, as well as response time (RT) for Trials 1 and 2, and total RT for both Trials. RESULTS: The SIM group produced significantly more errors than the CON group for Trials 1 and 2, and committed more total errors across trials. Significantly longer response latencies were found for the SIM group compared to the CON group for all RT indices examined. Linear regression modeling indicated excellent group classification for all indices studied, with areas under the curve ranging from 0.92 to 0.95. Sensitivity and specificity rates were good for several cut scores across all of the accuracy and RT indices, and sensitivity improved greatly by combining RT cut scores with the more traditional accuracy cut scores. CONCLUSION: Findings demonstrate the ability of the PASSOM to distinguish individuals instructed to feign cognitive impairment from those told to perform to the best of their ability.

Measures of cognitive functioning as predictors of treatment outcome for cocaine dependence.

Amlodipine is a calcium-channel antagonist with neuropharmacological properties believed to be protective against cerebral hypoperfusion, microinfarcts, and excitoxic cell death. Based on its pharmacological properties, we hypothesized that amlodipine would be associated with improved attention, processing speed, memory, and executive functioning at treatment follow-up in 84 cocaine-dependent individuals enrolled in a 12-week, placebo-controlled, double-blind clinical trial of amlodipine. We also hypothesized that better cognitive functioning at baseline would be associated with reduced cocaine use (negative urine drug screens) and longer treatment retention (last session attended). Results indicated that amlodipine produced no measurable benefit in cognitive functioning. Percent perseverative errors on Wisconsin Card Sorting Test was negatively correlated with treatment retention (n = 84, r = -.350, p < .01). No other findings were significant. Thus, cocaine-dependent individuals who repeated mistakes and benefited less from corrective feedback on a problem-solving task discontinued treatment earlier. Notably, no other cognitive measures predicted treatment outcome. The observed relationship implicates the relevance of executive functioning to treatment outcome for cocaine dependence.

A controlled trial of amlodipine for cocaine dependence: a negative report.

Preclinical models of cocaine dependence have shown favorable reductions in cocaine use using dihydropyridine calcium channel antagonists. This is one of the first reports testing the efficacy of the long-acting calcium channel antagonist, amlodipine, for the treatment of cocaine dependence. This was a 12-week, double-blind, randomized, placebo-controlled, parallel patient group trial of amlodipine vs. placebo for the treatment of cocaine dependence. One hundred and sixteen subjects participated in a 12-week medication trial in which 60 subjects received medication and 56 received placebo. Subjects in both groups received up to 12 standard manual-driven cognitive behavioral therapy sessions. Overall, drop-out rate for both groups was high, with only about 20% of subjects completing all 12 weeks of treatment. Both groups showed comparable levels of medication compliance and therapy attendance. In the end, amlodipine was no more effective than placebo in reducing craving or measured levels of cocaine use.

Substance abuse treatment outcomes for cognitively impaired and intact outpatients.

The purpose of this research was to examine the effects of cognitive impairment on the efficacy of substance abuse treatment outcome. Alcohol, drug, medical, legal, psychological, employment, and family functioning related treatment outcomes were examined for 26 cognitively impaired and 68 cognitively intact abusing outpatients. Subjects were enrolled in an intensive, 3-week, outpatient program for the treatment of their substance abuse. Subjects were administered a battery of neuropsychological tests prior to treatment onset, and outcome data were obtained at 1, 3, 6, and 12 months posttreatment entry. No significant between-group differences were found on any of the outcome measures, and significant treatment gains were observed across all problem domains in both groups. Subjects' largest improvements were made in the first month of treatment for alcohol, drug, legal, family, and psychological problems. Improvements for employment and medical problems were not observed until 6 months posttreatment. Success across domains was maintained through 12 months follow-up, with the exception of psychological problems; 12-month data indicated a return to thelevel observed at 30 days posttreatment for psychological problems, a level that reflected significant improvement from baseline functioning. A greater proportion of treatment dropouts (i.e., no follow-up data obtained after 30 days) were cognitively impaired as compared to treatment completers. These results suggest that this method of intensive substance abuse outpatient treatment is effective for cognitively impaired patients, an important finding given that research evaluating the efficacy of interventions for such patients is limited. Additionally, neuropsychological evaluation may be important in reducing treatment dropouts, as the present findings indicated that greater cognitive impairment was related to an increased likelihood of treatment dropout.