Synchronized HVC activity in auditory perception in canaries

AMADOR, A.; MINDLIN, G.B.; BOARI, S.

San Diego, CA

Congreso; SFN Neuroscience 2018; 2018

Society for Neuroscience

Songbirds have been the focus of neuroethological research of the principles underlying vocal production, perception and learning. The ´song system´ is a network of neural nuclei of a songbird´s brain dedicated to these tasks. Telencephalic nucleus HVC is involved in the generation of the motor commands for vocal production and receives highly processed auditory inputs. In asleep or anesthetized adult male zebra finches (Taeniopygia guttata), HVC selective single units respond to a playback of the bird?s own song (BOS). This elicited auditory response presents a similar firing pattern to the one measured while the bird is singing, suggesting a shared coding mechanism for the motor production and sensory perception of the BOS. For singing zebra finches, a recent study showed that HVC local field potentials (LFP) present defined oscillations in the 25-35 Hz band (Markowitz et al. 2015). While a correlation between LFP features and neuron firing was reported, it remains to be seen whether a link between LFP rhythmicity and song features can be established. In this work, we studied the auditory responses to BOS at HVC in urethane-anesthetized male adult canaries (Serinus canaria). Differently than the highly stereotyped song of zebra finches, canaries present song bouts that are longer and more variable, composed of subunits called phrases. Each phrase is, in turn, composed by the repetition of the same syllable, with repetition rates that range from 2 Hz to 35 Hz. For this species, the BOS was determined by assessing the most probable song bout within the bird?s natural repertoire. Acute extracellular neural recordings were conducted at HVC with 32 channel multi-electrode arrays, which provided the possibility to study spatial information together with temporal modulations of the neural activity. We recorded the LFP at different HVC sites and depths. As was reported for singing zebra finches, we have found that the LFPs at HVC present rhythmic oscillations. In this case, we found them to be locked to the syllabic rate of different song phrases, which could provide a new perspective on the study of the neural coding of auditory processing of song and its link to vocal behavior in songbirds