Age-Related Differences in Neural Correlates of Auditory Spatial Change Detection in Real and Virtual Environments.

Although virtual environments are increasingly used in research, their ecological validity in simulating real-life scenarios, for example, to investigate cognitive changes in aging populations, remains relatively unexplored. This study aims to evaluate the validity of a virtual environment for investigating auditory spatial change detection in younger and older adults. This evaluation was performed by comparing behavioral and neurophysiological responses between real and virtual environments. Participants completed an auditory change detection task, identifying sound source position changes relative to a reference position. In the real environment, sounds were presented through physical loudspeakers in a reverberant room. In the virtual environment, stimuli were delivered through headphones, accompanied by a head-mounted display showing a visual replica of the room. Participants showed higher accuracy for azimuth than for distance changes, regardless of age or environment, emphasizing humans' larger sensitivity to lateralized sounds. Event-related potentials were mostly consistent across environments, with significantly higher N1 and P2 amplitudes in older compared with younger adults. Mismatch negativity was reduced in older adults, and both reduced and delayed in the virtual environment. The P3b showed larger amplitudes and shorter latencies for azimuth changes, reflecting greater salience of directional cues, whereas responses in the virtual environment were slightly diminished, especially among older adults. Bayesian analyses validated the observed effects. Results support virtual environments as reliable tools for exploring spatial perception and underlying neural and behavioral processes in realistic contexts. Furthermore, differences in the processing of spatial changes in azimuth and distance, as well as age-related effects, could be highlighted.