Effects of enactment in episodic memory: a pilot virtual reality study with young and elderly adults.

Najate Jebara,Eric Orriols,Mohamed Zaoui,Alain Berthoz,Pascale Piolino

doi:10.3389/fnagi.2014.00338

Abstract

None of the previous studies on aging have tested the influence of action with respect to the degree of interaction with the environment (active or passive navigation) and the source of itinerary choice (self or externally imposed), on episodic memory (EM) encoding. The aim of this pilot study was to explore the influence of these factors on feature binding (the association between what, where, and when) in EM and on the subjective sense of remembering. Navigation in a virtual city was performed by 64 young and 64 older adults in one of four modes of exploration: (1) passive condition where participants were immersed as passengers of a virtual car [no interaction, no itinerary control (IC)], (2) IC (the subject chose the itinerary, but did not drive the car), (3) low, or (4) high navigation control (the subject just moved the car on rails or drove the car with a steering-wheel and a gas pedal on a fixed itinerary, respectively). The task was to memorize as many events encountered in the virtual environment as possible along with their factual (what), spatial (where), and temporal (when) details, and then to perform immediate and delayed memory tests. An age-related decline was evidenced for immediate and delayed feature binding. Compared to passive and high navigation conditions, and regardless of age-groups, feature binding was enhanced by low navigation and IC conditions. The subjective sense of remembering was boosted by the IC in older adults. Memory performance following high navigation was specifically linked to variability in executive functions. The present findings suggest that the decision of the itinerary is beneficial to boost EM in aging, although it does not eliminate age-related deficits. Active navigation can also enhance EM when it is not too demanding for subjects’ cognitive resources.

Highlights

Episodic memory (EM) contains specific events of one’s life and enables humans to travel back in personal time to re-experience events
The older participants were well matched across the four conditions concerning their cognitive flexibility and subjective memory complaints
Using a naturalistic environment created with virtual reality (VR), the present study aimed to assess the distinctive role of decision or motor control on feature binding, and to illuminate the relationships between binding, form of encoding, and aging in order to suggest new procedures that could improve feature binding by focusing on the influence of action at encoding

Summary

Introduction

Episodic memory (EM) contains specific events of one’s life and enables humans to travel back in personal time to re-experience events. People generally perform better on tests of item memory than on tests that require feature binding (Spencer and Raz, 1995; Chalfonte and Johnson, 1996; Mitchell et al, 2000; Kessels et al, 2007; Mitchell and Johnson, 2009). These deficits have been mainly associated with age-related effects on both the associative and strategic components of EM (Moscovitch, 1992; Shing et al, 2008; Piolino et al, 2010). The strategic component refers to cognitive control processes based on prefrontal regions that monitor memory functions at both encoding and retrieval (Simons and Spiers, 2003)

Methods

Results

Conclusion