title: Auditory synapses to song premotor neurons are gated off during vocalization in zebra finches.
abstract: Songbirds use auditory feedback to learn and maintain their songs, but how feedback interacts with vocal motor circuitry remains unclear. A potential site for this interaction is the song premotor nucleus HVC, which receives auditory input and contains neurons (HVCX cells) that innervate an anterior forebrain pathway (AFP) important to feedback-dependent vocal plasticity. Although the singing-related output of HVCX cells is unaltered by distorted auditory feedback (DAF), deafening gradually weakens synapses on HVCX cells, raising the possibility that they integrate feedback only at subthreshold levels during singing. Using intracellular recordings in singing zebra finches, we found that DAF failed to perturb singing-related synaptic activity of HVCX cells, although many of these cells responded to auditory stimuli in non-singing states. Moreover, in vivo multiphoton imaging revealed that deafening-induced changes to HVCX synapses require intact AFP output. These findings support a model in which the AFP accesses feedback independent of HVC. DOI: http://dx.doi.org/10.7554/eLife.01833.001.
authors.affiliation: Department of Neurobiology, Duke University Medical Center, Durham, United States.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Hamaguchi
authors.forename: Katherine A
authors.initials: KA
authors.lastname: Tschida
authors.forename: Inho
authors.initials: I
authors.lastname: Yoon
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Donald
authors.forename: Richard
authors.initials: R
authors.lastname: Mooney
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D001306:Auditory Pathways / Q000166:cytology / Q000502:physiology*; D001307:Auditory Perception; D001309:Auditory Threshold; D001931:Brain Mapping; D005072:Evoked Potentials, Auditory; D025461:Feedback, Physiological; D046369:Finches / Q000502:physiology*; D008297:Male; D008959:Models, Neurological; D009044:Motor Cortex / Q000166:cytology / Q000502:physiology*; D009473:Neuronal Plasticity; D013018:Sound Spectrography; D009435:Synaptic Transmission; D013997:Time Factors; D014828:Vocalization, Animal
keywords: auditory feedback; birdsong; sensorimotor; zebra finch