We have proposed that the primate auditory cortex is organized into three major regions: a core region of three primary-like areas, a belt region containing seven or eight areas bordering the core laterally and medially, and a parabelt region that has at least two subdivisions. Each region represents a successive level of processing, and subdivisions within each region are activated by parallel inputs. The first specific aim is directed at one of the most tentative aspects of this model, which suggests that the medial and lateral portions of the belt region are functionally-distinct. Patterns of cortical and subcortical connections differ between these two regions, and there is compelling electrophysiological evidence of auditory and somatosensory convergence in at least part of the medial belt. We will test the hypothesis that the medial and lateral belt regions mediate different aspects of auditory processing in experiments designed to determine the functional organization of individual fields. Multiunit recordings will be used to identify receptive field properties of neuronal clusters, topographic patterns, and boundaries between subdivisions. These data will guide the placement of neuronal tracers within individual fields to reveal cortical and subcortical connections. The anatomical and physiological data will be combined into functional profiles of each area to evaluate their contributions to auditory cortical processing, in general, and signficance with respect to the general hypothesis. A related issue concerns the extent to which the basic principles of auditory cortical organization in monkeys can be generalized to humans. As a second aim, we will compare architectonic features of auditory cortex in nonhuman primates and humans. Analyses of cytoarchitecture, myeloarchitecture, and the distribution of acetyicholinesterase, cytochrome oxidase, parvalbumin, calbindin, SMI-32, and CAT-301 will be combined to characterize and compare the architecture of core, belt, and parabelt fields in the auditory cortex of monkeys, apes, and humans. As suggested by functional studies in humans and nonhuman primates, we expect to find similarities across species, but important differences may exist that relate to functional specializations. Advancing our understanding of basic auditory cortical organization and processing is essential for continued efforts to evaluate the effects of pathology on auditory function, the capacity for recovery after injury, and the effeSECONDARY

Agency
National Institute of Health (NIH)
Institute
National Institute on Deafness and Other Communication Disorders (NIDCD)
Type
Research Project (R01)
Project #
5R01DC004318-03
Application #
6634510
Study Section
Special Emphasis Panel (ZRG1-IFCN-6 (01))
Program Officer
Luethke, Lynn E
Project Start
2001-04-01
Project End
2006-03-31
Budget Start
2003-04-01
Budget End
2004-03-31
Support Year
3
Fiscal Year
2003
Total Cost
$264,250
Indirect Cost
Name
Vanderbilt University Medical Center
Department
Otolaryngology
Type
Schools of Medicine
DUNS #
004413456
City
Nashville
State
TN
Country
United States
Zip Code
37212
Hackett, Troy A (2015) Anatomic organization of the auditory cortex. Handb Clin Neurol 129:27-53
Kajikawa, Yoshinao; Frey, Stephen; Ross, Deborah et al. (2015) Auditory properties in the parabelt regions of the superior temporal gyrus in the awake macaque monkey: an initial survey. J Neurosci 35:4140-50
Torii, Masaaki; Hackett, Troy A; Rakic, Pasko et al. (2013) EphA signaling impacts development of topographic connectivity in auditory corticofugal systems. Cereb Cortex 23:775-85
Smiley, John F; Hackett, Troy A; Preuss, Todd M et al. (2013) Hemispheric asymmetry of primary auditory cortex and Heschl's gyrus in schizophrenia and nonpsychiatric brains. Psychiatry Res 214:435-43
Balaram, Pooja; Hackett, Troy A; Kaas, Jon H (2013) Differential expression of vesicular glutamate transporters 1 and 2 may identify distinct modes of glutamatergic transmission in the macaque visual system. J Chem Neuroanat 50-51:21-38
Miller, Daniel J; Lackey, Elizabeth P; Hackett, Troy A et al. (2013) Development of myelination and cholinergic innervation in the central auditory system of a prosimian primate (Otolemur garnetti). J Comp Neurol 521:3804-16
Smiley, John F; Bleiwas, Cynthia (2012) Embedding matrix for simultaneous processing of multiple histological samples. J Neurosci Methods 209:195-8
de la Mothe, Lisa A; Blumell, Suzanne; Kajikawa, Yoshinao et al. (2012) Cortical connections of auditory cortex in marmoset monkeys: lateral belt and parabelt regions. Anat Rec (Hoboken) 295:800-21
Bryant, Katherine L; Suwyn, Carolyn; Reding, Katherine M et al. (2012) Evidence for ape and human specializations in geniculostriate projections from VGLUT2 immunohistochemistry. Brain Behav Evol 80:210-21
Camalier, Corrie R; D'Angelo, William R; Sterbing-D'Angelo, Susanne J et al. (2012) Neural latencies across auditory cortex of macaque support a dorsal stream supramodal timing advantage in primates. Proc Natl Acad Sci U S A 109:18168-73

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