title: Different forms of effective connectivity in primate frontotemporal pathways.
abstract: It is generally held that non-primary sensory regions of the brain have a strong impact on frontal cortex. However, the effective connectivity of pathways to frontal cortex is poorly understood. Here we microstimulate sites in the superior temporal and ventral frontal cortex of monkeys and use functional magnetic resonance imaging to evaluate the functional activity resulting from the stimulation of interconnected regions. Surprisingly, we find that, although certain earlier stages of auditory cortical processing can strongly activate frontal cortex, downstream auditory regions, such as voice-sensitive cortex, appear to functionally engage primarily an ipsilateral temporal lobe network. Stimulating other sites within this activated temporal lobe network shows strong activation of frontal cortex. The results indicate that the relative stage of sensory processing does not predict the level of functional access to the frontal lobes. Rather, certain brain regions engage local networks, only parts of which have a strong functional impact on frontal cortex.
authors.affiliation: 1] Institute of Neuroscience, Framlington Place, Newcastle University, Newcastle upon Tyne NE2 4HH, UK [2] Department of Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, 38 Spemannstrasse, 72076 Tübingen, Germany.
authors.forename: Christopher I
authors.initials: CI
authors.lastname: Petkov
authors.affiliation: 1] Institute of Neuroscience, Framlington Place, Newcastle University, Newcastle upon Tyne NE2 4HH, UK [2] Laboratory of Neuropsychology, NIMH, NIH, 31 Center Drive, Bethesda, Maryland 20892, USA [3] Department of Neuroscience, Georgetown University Medical Center, 3970 Reservoir Road, N.W., Washington, District of Columbia 20057, USA.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Kikuchi
authors.affiliation: Institute of Neuroscience, Framlington Place, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
authors.forename: Alice E
authors.initials: AE
authors.lastname: Milne
authors.affiliation: Laboratory of Neuropsychology, NIMH, NIH, 31 Center Drive, Bethesda, Maryland 20892, USA.
authors.forename: Mortimer
authors.initials: M
authors.lastname: Mishkin
authors.affiliation: 1] Department of Neuroscience, Georgetown University Medical Center, 3970 Reservoir Road, N.W., Washington, District of Columbia 20057, USA [2] Institute for Advanced Study, Technische Universität München, Lichtenbergstrasse 2a, Garching 85748, Germany.
authors.forename: Josef P
authors.initials: JP
authors.lastname: Rauschecker
authors.affiliation: 1] Department of Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, 38 Spemannstrasse, 72076 Tübingen, Germany [2] Division of Imaging Science and Biomedical Engineering, University of Manchester, Stopford Building, Oxford Road, Manchester M13 9PT, UK.
authors.forename: Nikos K
authors.initials: NK
authors.lastname: Logothetis
mesh_terms: D000818:Animals; D001303:Auditory Cortex / Q000502:physiology; D001306:Auditory Pathways / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods; D005625:Frontal Lobe / Q000473:pathology*; D007091:Image Processing, Computer-Assisted; D008253:Macaca mulatta; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009415:Nerve Net / Q000502:physiology; D009434:Neural Pathways / Q000502:physiology; D011323:Primates; D013016:Sound; D013702:Temporal Lobe / Q000473:pathology*