Functional anatomy of the auditory pathways

听觉通路的功能解剖学

• 批准号: 7089846
• 负责人: Brett R Schofield
• 金额: $ 33.08万
• 依托单位: NORTHEAST OHIO MEDICAL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-07-01 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7089846
• 关键词: acetylcholine; auditory cortex; auditory pathways; axon; electron microscopy; gamma aminobutyrate; guinea pigs; immunocytochemistry; inferior colliculus; neural information processing; neuroanatomy

DESCRIPTION (provided by applicant):The auditory system consists of ascending pathways that transmit information from the ear to the cortex, where sound is perceived, and descending pathways from the cortex that modulate the processing and flow of ascending information. The descending pathways are believed to play a role in a variety of functions, such as selective attention and discrimination of speech sounds, but understanding these roles is hindered by a lack of information on the neural circuitry. One of the largest descending pathways is from cortex to the inferior colliculus (IC), a prominent midbrain structure In at processes almost all ascending auditory information. Cortical projections activate subcortical circuits that use the neurotransmitters GABA and acetylcholine. These transmitters play prominent roles in the IC in normal function, in dysfunction such as tinnitus and in declining function associated with aging. The current proposal is focused on the relationships between descending cortical projections and the subcortical circuits that use GABA or acetylcholine to affect the IC. The proposed experiments will identify the source of acetylcholine inputs to the IC and characterize the cellular targets of those inputs. The experiments will also determine whether cortical proejctions make direct connections with the subcorical ceils that use GABA or acetylcholine and innervate the IC. The results will provide essential information on descending auditory pathways and specific subcortical circuits.

描述（由申请人提供）：听觉系统由将信息从耳朵传输到感知声音的皮层的上行通路和调节上行信息的处理和流动的来自皮层的下行通路组成。据信，下行通路在多种功能中发挥作用，例如选择性注意和语音辨别，但由于缺乏神经回路信息，理解这些作用受到阻碍。最大的下行通路之一是从皮质到下丘（IC），下丘是一种突出的中脑结构，负责处理几乎所有上行听觉信息。皮质投射激活使用神经递质 GABA 和乙酰胆碱的皮质下回路。这些递质在 IC 的正常功能、耳鸣等功能障碍以及与衰老相关的功能衰退中发挥着重要作用。目前的提案重点关注皮质下降投射与使用 GABA 或乙酰胆碱影响 IC 的皮质下回路之间的关系。拟议的实验将确定 IC 乙酰胆碱输入的来源，并表征这些输入的细胞靶标。实验还将确定皮质投射是否与使用 GABA 或乙酰胆碱并支配 IC 的皮质下细胞直接连接。结果将提供有关下行听觉通路和特定皮层下回路的重要信息。