title: Differences in the strength of cortical and brainstem inputs to SSA and non-SSA neurons in the inferior colliculus.
abstract: In an ever changing auditory scene, change detection is an ongoing task performed by the auditory brain. Neurons in the midbrain and auditory cortex that exhibit stimulus-specific adaptation (SSA) may contribute to this process. Those neurons adapt to frequent sounds while retaining their excitability to rare sounds. Here, we test whether neurons exhibiting SSA and those without are part of the same networks in the inferior colliculus (IC). We recorded the responses to frequent and rare sounds and then marked the sites of these neurons with a retrograde tracer to correlate the source of projections with the physiological response. SSA neurons were confined to the non-lemniscal subdivisions and exhibited broad receptive fields, while the non-SSA were confined to the central nucleus and displayed narrow receptive fields. SSA neurons receive strong inputs from auditory cortical areas and very poor or even absent projections from the brainstem nuclei. On the contrary, the major sources of inputs to the neurons that lacked SSA were from the brainstem nuclei. These findings demonstrate that auditory cortical inputs are biased in favor of IC synaptic domains that are populated by SSA neurons enabling them to compare top-down signals with incoming sensory information from lower areas.
authors.affiliation: Auditory Neurophysiology Laboratory. Institute of Neuroscience of Castilla Y León, University of Salamanca, C/Pintor Fernando Gallego, 1, 37007 Salamanca, Spain.
authors.forename: Yaneri A
authors.initials: YA
authors.lastname: Ayala
authors.affiliation: Department of Neuroscience, University of Connecticut Health Center, Farmington, CT 06030-3401, USA.
authors.forename: Adanna
authors.initials: A
authors.lastname: Udeh
authors.affiliation: Department of Neuroscience, University of Connecticut Health Center, Farmington, CT 06030-3401, USA.
authors.forename: Kelsey
authors.initials: K
authors.lastname: Dutta
authors.affiliation: Department of Neuroscience, University of Connecticut Health Center, Farmington, CT 06030-3401, USA.
authors.forename: Deborah
authors.initials: D
authors.lastname: Bishop
authors.affiliation: 1] Auditory Neurophysiology Laboratory. Institute of Neuroscience of Castilla Y León, University of Salamanca, C/Pintor Fernando Gallego, 1, 37007 Salamanca, Spain [2] Department of Neuroscience, University of Connecticut Health Center, Farmington, CT 06030-3401, USA [3] Department of Cell Biology and Pathology, Faculty of Medicine, University of Salamanca, Campus Miguel de Unamuno, 37007 Salamanca, Spain.
authors.forename: Manuel S
authors.initials: MS
authors.lastname: Malmierca
authors.affiliation: Department of Neuroscience, University of Connecticut Health Center, Farmington, CT 06030-3401, USA.
authors.forename: Douglas L
authors.initials: DL
authors.lastname: Oliver
mesh_terms: D000161:Acoustic Stimulation; D000222:Adaptation, Physiological; D000818:Animals; D001303:Auditory Cortex / Q000473:pathology / Q000502:physiology*; D001921:Brain / Q000473:pathology; D001931:Brain Mapping; D055724:Electrophysiological Phenomena; D005260:Female; D007150:Immunohistochemistry; D007245:Inferior Colliculi / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D010784:Photomicrography; D051381:Rats; D020318:Rats, Long-Evans