title: Intrinsic Connections of the Core Auditory Cortical Regions and Rostral Supratemporal Plane in the Macaque Monkey.
abstract: In the ventral stream of the primate auditory cortex, cortico-cortical projections emanate from the primary auditory cortex (AI) along 2 principal axes: one mediolateral, the other caudorostral. Connections in the mediolateral direction from core, to belt, to parabelt, have been well described, but less is known about the flow of information along the supratemporal plane (STP) in the caudorostral dimension. Neuroanatomical tracers were injected throughout the caudorostral extent of the auditory core and rostral STP by direct visualization of the cortical surface. Auditory cortical areas were distinguished by SMI-32 immunostaining for neurofilament, in addition to established cytoarchitectonic criteria. The results describe a pathway comprising step-wise projections from AI through the rostral and rostrotemporal fields of the core (R and RT), continuing to the recently identified rostrotemporal polar field (RTp) and the dorsal temporal pole. Each area was strongly and reciprocally connected with the areas immediately caudal and rostral to it, though deviations from strictly serial connectivity were observed. In RTp, inputs converged from core, belt, parabelt, and the auditory thalamus, as well as higher order cortical regions. The results support a rostrally directed flow of auditory information with complex and recurrent connections, similar to the ventral stream of macaque visual cortex.
authors.affiliation: Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health (NIMH/NIH), Bethesda, MD 20892, USA.
authors.forename: Brian H
authors.initials: BH
authors.lastname: Scott
authors.affiliation: Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health (NIMH/NIH), Bethesda, MD 20892, USA.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Leccese
authors.affiliation: Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health (NIMH/NIH), Bethesda, MD 20892, USA.
authors.forename: Kadharbatcha S
authors.initials: KS
authors.lastname: Saleem
authors.affiliation: Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health (NIMH/NIH), Bethesda, MD 20892, USA.|Present address: Institute of Neuroscience, Newcastle University Medical School, Newcastle Upon Tyne NE2 4HH, UK.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Kikuchi
authors.affiliation: Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health (NIMH/NIH), Bethesda, MD 20892, USA.
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Mullarkey
authors.affiliation: Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health (NIMH/NIH), Bethesda, MD 20892, USA.
authors.forename: Makoto
authors.initials: M
authors.lastname: Fukushima
authors.affiliation: Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health (NIMH/NIH), Bethesda, MD 20892, USA.
authors.forename: Mortimer
authors.initials: M
authors.lastname: Mishkin
authors.affiliation: Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health (NIMH/NIH), Bethesda, MD 20892, USA.
authors.forename: Richard C
authors.initials: RC
authors.lastname: Saunders
mesh_terms: D000818:Animals; D001303:Auditory Cortex / Q000166:cytology*; D001306:Auditory Pathways / Q000166:cytology; D005260:Female; D008253:Macaca mulatta; D008297:Male; D056347:Neuroanatomical Tract-Tracing Techniques; D009474:Neurons / Q000166:cytology
keywords: SMI-32; auditory cortex; pathways; rhesus; temporal lobe