Project 2 - Behavioral/Neuroscience

正常的衰老伴随着认知控制的下降，这部分是由受损的 前额皮质功能然而前额叶的变化对其他皮质结构的影响 被招募来进行认知控制的人还不太了解。在这个项目中，听觉空间注意力的控制将 可以用来研究前额叶和后皮质区域之间的相互作用，以及这些相互作用是如何发生的。 受年龄和任务要求的影响。我们的总体假设是，与年龄相关的认知变化 控制是由前额叶和顶叶/颞叶之间协调的网络水平损伤介导的 叶区。推论假设是，老化与空间注意力梯度受限有关 (Aim 1），和更大的敏感性，空间定向知觉和短期记忆负荷操纵 (Aim磁刺激大脑皮层可改善上述两种情况（目的3）。方法包括使用 脑电图和事件相关电位，以确定皮层处理和前额叶和 后区。空间梯度将通过呈现来自位置的声学虚拟现实刺激来映射 在执行任务期间的正面方位平面中。经颅磁刺激将用于 暂时影响前额叶皮层活动经颅磁刺激的效果将是 使用行为和EEG/事件相关电位测量进行评估。提出了三个具体目标。 在目标1中，空间注意力梯度的年龄差异将使用神经电测量进行评估， 自动（不匹配负性）和控制（P3 a）处理分心刺激。目标2将测试 假设认知控制的下降与感知能力的降低有关， 对短期记忆的前摄干扰单独的实验将参数化地改变感知或 短期记忆负荷，并单独评估高与低主动干扰条件， 记忆负荷实验目标3将确定磁刺激皮质是否可以扩大空间 注意力梯度和提高认知控制任务的性能。

Normal aging is accompanied by declines in cognitive control that are mediated, in part, by compromised prefrontal cortex function. However the repercussions of prefrontal changes on other cortical structures recruited for cognitive control are not well understood. In this project control of auditory spatial attention will be used to study interactions between prefrontal and posterior cortical regions, and how these interactions are affected by age and task demands. Our overarching hypothesis is that age-related changes in cognitive control are mediated by network level impairments in coordination between prefrontal and parietal/temporal lobe areas. Corollary hypotheses are that aging is associated with constrained spatial attention gradients (Aim 1), and greater sensitivity of spatial orienting to perceptual and short-term memory load manipulations (Aim 2), both of which can be improved by magnetic stimulation of cortex (Aim 3). Methods include using EEG and event-related potentials to define cortical processing and interactions between prefrontal and posterior areas. Spatial gradients will be mapped by presenting acoustic virtual reality stimuli from locations in the frontal azimuth plane during task performance. Transcranial magnetic stimulation will be used to temporarily influence prefrontal cortical activity. The effects of transcranial magnetic stimulation will be assessed using behavioral and EEG/event-related potential measures. Three Specific Aims are proposed. In Aim 1 age differences in spatial attention gradients will be assessed using neuroelectric measures of automatic (mismatch negativity) and controlled (P3a) processing of distractor stimuli. Aim 2 will test the hypothesis that declines in cognitive control are associated with reduced perceptual capacity and greater proactive interference in short-term memory. Separate experiments will parametrically vary perceptual or short-term memory load, with a separate assessment of high vs. low proactive interference conditions in the memory load experiments. Aim 3 will determine if magnetic stimulation of cortex can broaden spatial attention gradients and improve performance on cognitive control tasks.