Test-retest reliability and practice effects of the virtual environment grocery store (VEGS)

Performance on a virtual environment shopping task and adaptive functioning among older adults

Neuropsychologists are often asked to evaluate patients' functional capacities, yet traditional neuropsychological tests have limited correspondence with real-world outcomes. The Virtual Environment Grocery Store (VEGS) is a virtual environment that simulates shopping tasks. The purpose of this study was to investigate the relationship between older adults' performance on the VEGS in relation to their self-reported adaptive functioning as well as performance on a performance-based adaptive functioning measure. Older adults (n = 98; age 65-90, M = 75.82, SD = 6.27) were administered the VEGS, the Instrumental Activities of Daily Living Scale (IADLS), and the Texas Functional Living Scale (TFLS). Neither premorbid functioning nor the VEGS variables were associated with self-rated adaptive functioning. However, all three VEGS variables were associated with performance-based adaptive functioning (i.e., the TFLS). Performance on the VEGS measure of correct items in the shopping cart explained 13.9% of the variance in performance on the performance-based adaptive functioning task. Whether the participant picked up the VEGS prescription explained 12.6% of the variance in performance on the performance-based adaptive functioning task. Performance on VEGS long delay free recall explained 35.1% of the variance in performance on the performance-based adaptive functioning task. These results suggest that the VEGS demonstrates value in predicting older adults' functional capacities.

Comparison of Traditional and Virtual Reality-Based Episodic Memory Performance in Clinical and Non-Clinical Cohorts

The California Verbal Learning Test, Second Edition (CVLT-II) and the Virtual Environment Grocery Store (VEGS) use list learning and recognition tasks to assess episodic memory. This study aims to: (1) Replicate prior construct validity results among a new sample of young adults and healthy older adults; (2) Extend this work to a clinical sample of older adults with a neurocognitive diagnosis; (3) Compare CVLT-II and VEGS performance among these groups; and (4) Validate the independence of CVLT and VEGS episodic memory performance measures from executive functioning performance measures. Typically developing young adults (n = 53) and older adults (n = 85), as well as older adults with a neurocognitive diagnosis (n = 18), were administered the CVLT-II, VEGS, and D-KEFS CWIT. Results found that (1) the relationship of the VEGS and CVLT-II measures was highly correlated on all variables, (2) compared to the CVLT-II, participants (particularly older adults) recalled fewer items on the VEGS, and (3) the CVLT-II and VEGS were generally independent of D-KEFS CWIT. It appeared that the VEGS may be more difficult than the CVLT-II, possibly reflecting the word length effect. Performance may have also been impacted by the presence of everyday distractors in the virtual environment.