Visual-Somatosensory Integration in Older Adults: Links to Sensory Functioning

Source: Volume 29, Issue 4-5, pp 397 - 420Research investigating multisensory integration (MSI) processes in aging is scarce, but converging evidence for larger behavioral MSI effects in older compared to younger adults exists. The current study employed a three-prong approach to determine whether inherent age-related sensory processing declines were associated with larger (i.e., worse) visual-somatosensory (VS) reaction time (RT) facilitation effects. Non-demented older adults ( n = 156 ; mean age = 77 years; 55% female) without any medical or psychiatric conditions were included. Participants were instructed to make speeded foot-pedal responses as soon as they detected visual, somatosensory, or VS stimulation. Visual acuity was assessed using the Snellen test while somatosensory sensitivity was determined using vibration thresholds. The aims of the current study were to: (1) replicate a reliable MSI effect; (2) investigate the effect of unisensory functioning on VS RT facilitation; and (3) determine whether sensory functioning combination groups manifested differential MSI effects. Results revealed a significant VS RT facilitation effect that was influenced by somatosensory sensitivity but not visual acuity. That is, older adults with poor somatosensory sensitivity demonstrated significantly larger MSI effects than those with intact somatosensory sensitivity. Additionally, a significant interaction between st...
Source: Multisensory research - Category: Neuroscience Authors: Source Type: research