Day 121 MCAT Practice Question

Passage 1

Declining long-term memory (LTM) impacts diverse aspects of cognitive

performance and overall quality of life for many healthy older adults. Chronic

memory loss is typically first apparent as reduced capability for high-fidelity

memory, which is the most precise form of LTM. High-fidelity memory depends

upon flexible association of diverse bits of information for facts and events that

are remembered in distinct and detailed terms, and it can be conceptualized in

terms of source, associative, and autobiographical memory, as well as mnemonic

discrimination as a behavioral task to operationalize pattern separation processes.

To our knowledge, there has yet to be any cognitive or pharmaceutical interventions

that have demonstrated restorative effects for the decline in high-fidelity LTM that

occurs with aging.

We developed a virtual reality (VR) spatial wayfinding game (Labyrinth-VR) as a

cognitive intervention with the hypothesis that it could improve detailed, highfidelity LTM capability.

In the current study, 48 older adults (mean age 68.7±6.4 years) with average

cognitive abilities for their age were randomly assigned to 12 h of computer game

play over four weeks in either the Labyrinth-VR or placebo control game arms.

Promptly before and after each participant’s treatment regimen, high-fidelity LTM

outcome measures were tested to assess mnemonic discrimination and other

memory measures.

Figure 1: Comparisons of LDI for Younger, Older and Labyrinth-VR Participants. (A)

Mean LDI scores for participants in the Labyrinth-VR arm in Experiment 2 (i.e., at

baseline, T1, and post-training assessments, T2) are compared to the mean LDI

scores for groups of younger and older adults that completed the same Mnemonic

Discrimination Task in Experiment 1. Labyrinth-VR participants at T1 showed a

diminished level of LDI typical of older adults (OA), and then they improved this

important high-fidelity LTM capability at T2 up to a level typical for younger adults

(YA). (B) Mean LDI scores for participants in the Control arm in Experiment 2, at both

T1 and T2, were below the mean level of YA in experiment 1. ** indicates a difference

between means, p < 0.001, and * indicates a difference between means, p < 0.05.

The results showed a post-treatment gain in high-fidelity LTM capability for the

Labyrinth-VR arm, relative to placebo, which reached the levels attained by younger

adults in another experiment. This novel finding demonstrates generalization of

benefits from the VR wayfinding game to important, and untrained, LTM capabilities.

In summary, comparisons for the effects of the Labyrinth-VR intervention on

mnemonic discrimination found that older participants, who, on average, had shown

an age-typical level of diminished LDI at baseline, then improved this important

high-fidelity LTM capability after treatment up to a level typical for younger adults. This pattern in improvement suggests that the Labyrinth-VR intervention can restore

high-fidelity LTM capability for older adults to the typical level of younger adults.

Virtual reality video game improves high-fidelity memory in older adults. Adapted

from Wais et al. (2021).

The passage describes various forms of high-fidelity memory. Which of

the following memory types are correctly paired with their description? -

COMPLETE

A) Source memory: long-term memories that are associated with sensory

information, such as olfactory or tactile data

B) Long-term memory: memories that have undergone permanent

consolidation and cannot be altered

C) Autobiographical memory: memory of personal details gained from one’s

own experiences

D) Associative memory: memory that allows one to associate long-term

memories with short-term memories