Humans with traumatic brain injuries show place-learning deficits in computer-generated virtual space

Spatial learning and memory has been linked to the hippocampus and temporal lobes and though these areas are often damaged in traumatic brain injury (TBI), spatial learning deficits after TBI have not received much attention. In the present study, a virtual environment was used to challenge people with TBI to solve a task comparable to the Morris water maze, which in turn has been shown to be highly sensitive to hippocampal and frontal lobe dysfunction in laboratory animals. A regular computer monitor was used to present 12 participants with TBI and 12 age- and sex-matched comparison participants with a computer-generated, three-dimensional 'virtual arena maze,' consisting of a large round arena within a very large square room. Participants were required to learn the place of an invisible target on the floor of the room based solely on distal cues on the walls of the room. Eight of the 12 participants with moderate to severe TBI showed substantial place- learning deficits in comparison to the uninjured participants. Performance in the virtual environment correlated with self-reported frequency of wayfinding problems in everyday life and with scores on a test of episodic memory, the Rivermead Behavioural Memory Task. These data confirm that deficits in spatial learning and memory follow TBI, and suggest that the virtual arena maze may provide a new method for objectively assessing them.