Effect of eye movement reactivation on visual memory among individuals with moderate-to-severe traumatic brain injury (TBI)

Objective: Previous research has shown that when individuals are asked questions referring to previously seen visual stimuli, their eye movements spontaneously return to the visual area where the stimuli were first seen. This recurring eye movement phenomenon has been shown to assist the memory retrieval of visual images. Individuals with moderate-to-severe traumatic brain injury (TBI) typically suffer from visual memory deficits as well as difficulty in spontaneously initiating mnemonic strategies. Perhaps TBI patients have trouble employing the eye movement reactivation strategy, thus further contributing to the visual memory deficits so prevalent among this population. Method: In this study, 27 healthy individuals and 27 patients with moderate-to-severe TBI from the Lowenstein Rehabilitation Hospital participated in a memory task. Participants were first exposed to stimuli and were then asked questions about the displayed stimuli. The testing session was conducted for each participant under two conditions: (1) while eyes were free to move over the screen; (2) while eyes were fixated. Results: Study findings show that the control group significantly benefitted from the free viewing in comparison to the fixed viewing condition, while this effect was absent among the TBI group. This was corroborated by eye tracking data showing that participants with TBI showed a minimal tendency to reactivate eye movements effectively, as occurs among the healthy group. Conclusions: The research findings expand our comprehension of visual memory among the TBI population, presenting rehabilitation health clinicians with new directions in understanding visual memory deficits.