Improving Memory Performance by Applying Cognitive Training

Duke University33 enrolled

Overview

The proposed study will test the efficacy of a cognitive training program to improve working memory in a sample of HIV-infected persons. Investigators will assign 40 HIV-infected adults with poor medication adherence to one of two conditions (20/group): the experimental cognitive training intervention or a control training condition. Participants will complete 12 training sessions across 10 weeks and will complete assessments at baseline and post-training. The specific aims are to: 1. Investigate the effects of the cognitive training intervention on working memory and delay discounting in HIV-infected persons. Hypothesis 1: Participants assigned to active cognitive training, compared to those in the attention-matched control group, will have greater improvements in working memory and reductions in delay discounting. 2. Characterize adherence to antiretroviral medications in this population and examine medication adherence after cognitive training. Hypothesis 2: Participants assigned to active cognitive training, compared to those in the attention-matched control group, will have greater improvements in medication adherence.

This study tests the feasibility and preliminary efficacy of a computerized cognitive training program to improve working memory and decrease impulsivity among HIV-infected individuals with poor medication adherence. The specific aims are to: (1) Investigate the effects of the cognitive training intervention on working memory and delay discounting in HIV-infected persons; and (2) Characterize adherence to antiretroviral medications in this population and examine medication adherence after cognitive training. The research design includes two parts: an eligibility screening and the Cognitive Training study. In Part 1, Eligibility Screening, participants will complete a 2-3 hour battery of standardized measures to assess for study eligibility. Eligible individuals will then be invited to enroll in Part 2, Cognitive Training Study. Part 1 of the study will involved screening approximately 60 participants, with an estimated eligibility rate of 67% for Part 2. In Part 2, participants will be assigned to one of two groups (active cognitive training or control training; 20 participants per group) and will complete 12 training sessions over 10 weeks. Participants assigned to the active cognitive training group will complete computerized modules designed to enhance working memory, while those assigned to the attention-matched control group will complete inactive modules that are not designed to enhance memory. All Part 2 participants will complete assessments at baseline and post-training to evaluate the impact of the training program.

Study Type

Eligibility

Sex: ALLMin age: 18 YearsMax age: 60 Years

Medical Language ↔ Plain English

Inclusion Criteria: * HIV infection, diagnosed for \> 6 months * Currently on treatment with antiretroviral medications for \> 3 months * Self-reported medication adherence at less than 90% * Lives within 15 miles of the research site in stable housing and with no plans to move from the area in the next 3 months Exclusion Criteria: * Current substance use disorder * Any drug use other than alcohol or marijuana in the past year * Pregnancy * English non-fluency or illiteracy * ≤ 8th grade education * serious neurological disorders, including HIV dementia * traumatic brain injury * severe mental illness or acute psychiatric distress * impaired mental status

Outcomes

Primary Outcomes

Change in Working Memory

Standardized neuropsychological tests of working memory used in this study were the Paced Auditory Serial Addition Task-50 and Neuropsychological Assessment Battery Digits Forward/Digits Backward Test. Using the most up-to-date published normative data, raw test scores were converted to T-scores that corrected for demographic factors such as age and education. T scores can range from 0 to 100, with 50 being average and higher scores indicating better function. The overall working memory score was computed by averaging T-scores of each of the individual tests. To examine intervention effects on working memory outcomes, we conducted a 2 (Arm: ACT vs. CON) × 2 (Time: Baseline vs. Post) mixed-model general linear model analyses. Time was the within-subjects factor defined by baseline versus 10 week follow-up, and study arm was the between-subjects factor. Age and years of education were included as covariates. The means reported here are the mean scores at 10 weeks.

Time frame: Baseline and 10 weeks

Secondary Outcomes

Change in Delay Discounting

Measured by Monetary-Choice Questionnaire (MCQ), a standardized task that measures delay discounting. Participants are presented with choices between smaller, immediate rewards and larger, delayed rewards (e.g., "Would you prefer $54 today or $80 in 30 days?). Participants' hyperbolic discount parameter (k value) is determined by fitting data to the following discount function equation: Vimmediate = Vdelayed / (1 + kD), in which V is the reward value in dollars and D is delay in days. K-values on this scale can range from 0.00016 to 4.00 and to normalize scores, these values were ranked from 1 to 13 for analyses. A higher rank indicates greater delay discounting.