Dumas Kristina, Holtzer Roee, Mahoney Jeannette R
Multisens Res. 2016;29(4-5):397-420. doi: 10.1163/22134808-00002521.
Research 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 stimulus condition and sensory functioning group suggested that the group with poor visual acuity and poor somatosensory functioning demonstrated the largest MSI effect compared to the other groups. In summary, the current study reveals that worse somatosensory functioning is associated with larger MSI effects in older adults. To our knowledge, this is first study to identify potential mechanisms behind increased RT facilitation in aging.
关于衰老过程中多感官整合（MSI）过程的研究很少，但有越来越多的证据表明，与年轻人相比，老年人在行为上的MSI效应更大。本研究采用了一种三管齐下的方法，以确定与年龄相关的固有感觉处理能力下降是否与更大（即更差）的视觉-体感（VS）反应时间（RT）促进效应有关。纳入了156名无任何医学或精神疾病的非痴呆老年人（平均年龄 = 77岁；55%为女性）。参与者被要求在检测到视觉、体感或VS刺激后尽快做出快速的脚踏反应。使用斯内伦视力表评估视力，同时使用振动阈值确定体感敏感性。本研究的目的是：（1）复制可靠的MSI效应；（2）研究单感官功能对VS RT促进的影响；（3）确定感觉功能组合组是否表现出不同的MSI效应。结果显示，VS RT促进效应显著，且受体感敏感性影响，但不受视力影响。也就是说，体感敏感性差的老年人表现出的MSI效应明显大于体感敏感性正常的老年人。此外，刺激条件和感觉功能组之间的显著交互作用表明，与其他组相比，视力差且体感功能差的组表现出最大的MSI效应。总之，本研究表明，较差的体感功能与老年人更大的MSI效应有关。据我们所知，这是第一项确定衰老过程中RT促进增加背后潜在机制的研究。
