Recent cocaine use and memory impairment in HIV

Impaired verbal memory in individuals living with HIV and cocaine dependence

INTRODUCTION

Our study aimed to understand the independent and combined effects of cocaine dependence and HIV status across aspects of verbal memory.

METHOD

Our sample consisted of a total of 102 individuals: 28 individuals living with HIV and cocaine dependence (HIV+/CD), 28 individuals who are HIV-negative with cocaine dependence (HIV-/CD), 20 individuals living with HIV without cocaine dependence (HIV+/ND), and 26 individuals who are HIV-negative without cocaine dependence (HIV-/ND). We utilized the Hopkins Verbal Learning Test-Revised Version (HVLT-R) to assess components of verbal memory, including encoding, recall, and recognition. A 2 (HIV: Yes/No) × 2 (Cocaine: Yes/No) MANCOVA on Total and Delayed Recall while controlling for premorbid intelligence was conducted. We used a Kruskal-Wallis H test to examine retrieval and recognition.

RESULTS

The combination of HIV and cocaine dependence amplified deficits on Total Recall. We found comparably poor performance across Delayed Recall between all three clinical groups. People living with HIV without cocaine dependence demonstrated intact recognition, whereas those with cocaine dependence had poor recognition.

CONCLUSIONS

HIV and cocaine both impacted verbal memory. However, there are potential subtle differences in the role cocaine versus HIV has on the memory process. People living with HIV without cocaine dependence recognized significantly more words than they could freely recall. In contrast, cocaine dependence impacted recognition in HIV and non-HIV groups. These performance patterns suggest HIV may be associated with retrieval deficits, whereas cocaine dependence may be associated with encoding deficits. Further research assessing these specific components of the memory process will help clarify these potential differences.

Memory in multiple sclerosis: A reappraisal using the item specific deficit approach

OBJECTIVE

As many as 65% of people with multiple sclerosis (MS) have clinically significant memory impairment, but the nature of this deficit is controversial. Some investigations suggest that an inability to retrieve newly learned information from memory is prominent, whereas others imply that compromised acquisition accounts for impairment. Prior research has not simultaneously evaluated acquisition and retrieval processes in MS, and fewer have attempted to account for initial acquisition when studying retrieval. The Item Specific Deficit Approach (ISDA) offers a method of quantifying acquisition, retrieval, and retention processes, with the latter two mechanisms being adjusted for initial acquisition. To simultaneously quantify acquisition and retrieval abilities, the ISDA was applied to list learning performance in two independent samples of people with MS and corresponding healthy comparison groups.

PARTICIPANTS AND METHODS

Study 1 included 85 people with MS and 47 healthy individuals. Study 2 involved a separate sample of 79 people with MS and 22 healthy people. They were administered neuropsychological batteries, and participants with MS were classified as globally impaired or unimpaired. The California Verbal Learning Test-II was administered to assess new-learning in both studies, and responses were scored using the ISDA.

RESULTS

Both studies revealed that cognitively impaired people with MS manifest weaknesses involving acquisition and retrieval. Nearly identical effect sizes emerged across samples, with cognitive impairment achieving a medium effect upon acquisition and a large effect upon retrieval.

CONCLUSIONS

These findings accord well with previous research showing diminished acquisition and retrieval among people with MS. The results may also reconcile contradictory findings in the extant literature by showing that memory impairment in MS is not exclusively attributable to either acquisition or retrieval. Rather, both processes may manifest across people with MS. The replication across samples with nearly identical effect sizes implies that these effects are reliable and possess external validity. These data hold implications for memory rehabilitation interventions involving people with MS, and suggest that acquisition and retrieval processes should be addressed in treatment. (PsycInfo Database Record (c) 2021 APA, all rights reserved).