Neural Determinants of Age-Related Changes in Cross-Sensory Plasticity and Multisensory Integration Affecting Audiovisual Speech Perception

影响视听言语感知的跨感觉可塑性和多感觉整合的年龄相关变化的神经决定因素

• 批准号: 10675866
• 负责人: James William Dias
• 金额: $ 45.53万
• 依托单位: MEDICAL UNIVERSITY OF SOUTH CAROLINA
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-01 至 2028-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10675866
• 关键词: Affect; Age; Area; Auditory; Auditory Evoked Potentials; Auditory area; Blindness; Cognitive; Communication; Compensation; Development; Diffusion; Elderly; Electrophysiology (science); Evoked Potentials; Exhibits; Hearing; Image; Individual Differences; Inferior; Intervention; Knowledge; Measures; Modality; Modeling; Neurophysiology - biologic function; Patient Self-Report; Research; Research Project Grants; Role; Sensory; Source; Speech; Speech Perception; Stream; Structure; System; Testing; Translating; Vision; Visual; Visual Cortex; Visual evoked cortical potential; age effect; age group; age related; audiovisual speech; auditory stimulus; behavior test; cognitive ability; frontal lobe; hearing impairment; improved; individual variation; innovation; interest; multisensory; neural; neuromechanism; novel; preservation; processing speed; programs; response; sensory cortex; sensory input; sensory integration; sensory stimulus; speech in noise; structural imaging; transmission process; visual speech; visual stimulus; white matter; young adult

PROJECT SUMMARY Older adults have more difficulty than younger adults identifying auditory (AO) and visual (VO) speech. Despite these unisensory deficits, some older adults can identify audiovisual (AV) speech as accurately as younger adults. Older adults have been found to exhibit more cross-modal plasticity, multisensory integration, and frontal-cortical modulation of sensory input, but the extent to which these age-related changes are beneficial and explain the conserved AV speech of older adults is a critical knowledge gap. The aims of the proposed research program will use an innovative neural systems approach incorporating electrophysiology (EEG), structural imaging (sMRI), and diffusion imaging (DKI) to characterize the specific neural mechanisms that adapt with age to support AV speech. Source-constrained analyses incorporating EEG and sMRI will be used to calculate potentials generated in specific regions of interest and the functional connectivity between regions of interest. Cross-modal plasticity will be characterized by cross-sensory response amplitudes (visual-evoked potentials generated in auditory cortex and auditory-evoked potentials generated in visual cortex) and the functional connectivity between auditory and visual cortex (Aim 1). Multisensory integration will be characterized by AV response amplitudes generated in temporoparietal cortex and the functional connectivity between temporoparietal cortex and sensory cortex (Aim 2). Frontal-cortical modulation of sensory input will be characterized by speech-evoked potentials generated in inferior frontal cortex and the functional connectivity between inferior frontal cortex and sensory cortex and between inferior frontal cortex and temporoparietal cortex (Aim 3). We hypothesize that the negative effects of age-related unisensory deficits on AV speech perception will be ameliorated by greater reliance on cross-modal plasticity (Aim 1), multisensory integration (Aim 2), and/or frontal-cortical modulation of sensory input (Aim 3). Though functional connectivity is hypothesized to facilitate each of these mechanisms and conserve the AV speech of older adults, age- related white matter degradation (DKI) is expected to limit functional connectivity, such that any age-related increases in functional connectivity may be moderated by age-related deficits in white mater integrity. While we hypothesize that each mechanism can on its own partially account for the conserved AV speech of some older adults, individual differences and variability between mechanisms are expected to account for why some older adults exhibit conserved AV speech perception while others do not. Importantly, we will also examine the extent to which the conserved AV speech demonstrated by some older adults translates to better perceived speech communication ability in day-to-day settings, as measured by self-report assessments. Identifying the mechanisms important for the conservation of AV speech in older adults can elucidate new targets for intervention to help preserve or even restore the communicative abilities of older adults with sensory deficits.

项目摘要 老年人比识别听觉（AO）和视觉（VO）演讲的年轻人更加困难。尽管 这些单性缺陷，一些老年人可以像年轻人一样准确地识别视听（AV） 成年人。已经发现老年人表现出更多的跨模式可塑性，多感官整合和 感觉输入的额叶皮质调制，但是这些与年龄相关的变化的程度是有益的 并解释老年人保守的AV演讲是一个关键的知识差距。提议的目的 研究计划将使用融合电生理学（EEG）的创新神经系统方法， 结构成像（SMRI）和扩散成像（DKI），以表征特定的神经机制 随着年龄的增长以支持AV演讲。将使用汇总EEG和SMRI的源限制的分析 计算在特定的感兴趣区域和区域之间的功能连通性中产生的电位 感兴趣的。跨模式可塑性的特征是跨感官响应幅度（视觉诱发的 在听觉皮层和听觉诱发的电位中产生的电位在Visual Cortex中产生的电位）和 听觉和视觉皮层之间的功能连接性（AIM 1）。多感官集成将是 以颞叶层皮质和功能连接性产生的AV响应幅度为特征 在颞叶皮质和感觉皮层之间（AIM 2）。感觉输入的正面皮质调制将 以下额皮层和功能性产生的语音诱发电位为特征 下额皮层和感觉皮质之间以及下部额叶皮层和感觉皮质之间的连通性 颞叶皮质（AIM 3）。我们假设与年龄相关的单性缺陷的负面影响对 AV语音感知将通过更大的跨模具可塑性（AIM 1），多感官来改善 集成（AIM 2）和/或感觉输入的额叶皮层调制（AIM 3）。虽然功能连接 假设可以促进这些机制中的每一种，并保留老年人的AV语言，年龄 相关的白质降解（DKI）有望限制功能连接，因此任何与年龄有关的连通性 功能连通性的提高可能会通过白人孕妇完整性与年龄相关的缺陷来调节。当我们 假设每种机制都可以自身解释一些较旧的较旧的AV演讲 成人，个体差异和机制之间的变异性应解释为什么有些年龄较大 成年人表现出保守的AV语音感知，而其他人则没有。重要的是，我们还将检查 保守的AV语音在某些老年人中所展示的范围转化为更好的感知 通过自我报告评估衡量的日常设置中的语音交流能力。识别 对于老年人保护AV语音至关重要的机制可以阐明新目标 干预措施有助于保存甚至恢复具有感官缺陷的老年人的交流能力。