elective alteration of song production to study sensorimotor integration in zebra finches

A. AMADOR AND D. MARGOLIASH

Salamanca

Conferencia; 9th International Congress of Neuroethology; 2010

International Society of Neuroethology

Songbirds has been widely studied as a model for vocal learning. As humans, they rely on hearing a tutor and own vocalizations during the learning process. Auditory feedback is also a key feature in humans and songbirds for maintaining adult vocalizations, as deafened individuals present gradually degradation of the vocal production. However, the mechanisms underlying the role of auditory feedback remain largely unknown. To allow for better experimental control of the auditory feedback a bird experiences during singing, we are developing a novel method for individual syllable manipulation. We have achieved fine control of the song production in zebra finches by modifying the subsyringeal pressure. A phonation pressure threshold can be defined as the minimum subsyringeal pressure required to initiate labial oscillation required for sound production. This threshold may be syllable dependent. We reduce the air sac pressure to subthreshold values by opening a flexible tube that is inserted in the air sac system. Dynamic control of the opening is achieved with a miniature valve (circa 10 ms opening time) that is attached at the end of the tube. The muting interval can be less than a syllable but extend to an entire motif, which is major unit of song production comprising multiple syllables. The advantage of this method is that for short duration disruptions, the motor gestures (defined as the activity of syringeal and respiratory muscles) are not directly compromised. It is important to notice that this method is reversible as the implant can be removed and the air sac sealed. Prior studies of the role of auditory feedback in song control in normal hearing birds have relied either on noise playback or delayed syllable playback. These have the disadvantage of superimposing external sounds onto feedback from the bird's singing. In the present experiment, we are studying the sensorimotor integration when no auditory input is received (muted syllable) and when the muted syllable is replaced with an acoustically modified syllable.