Bottom-up activation of the vocal motor forebrain by the respiratory brainstem

Using both sides of your brain: the case for rapid interhemispheric switching

Individual brain hemispheres are often specialized for specific aspects of a behavior. How both sides of the brain coordinate their output to produce a perfectly seamless behavior is not known. Songbirds appear to achieve this by rapidly switching back and forth between hemispheres.

Using temperature to analyse temporal dynamics in the songbird motor pathway

Many complex behaviors, like speech or music, have a hierarchical organization with structure on many timescales. How does the brain control the timing of behavioral sequences? Do different circuits control different timescales of the behavior? To address these questions, we use temperature to manipulate the biophysical dynamics in different regions of the songbird forebrain involved in song production. We found that cooling premotor nucleus HVC (proper name) slows song speed across all timescales by up to 45% while only slightly altering the acoustic structure, whereas cooling downstream motor nucleus RA (robust nucleus of the arcopallium) has no observable effect on song timing. Our observations suggest that dynamics within HVC are involved in the control of song timing, perhaps through a chain-like organization. Local manipulation of brain temperature should be broadly applicable to identify neural circuitry that controls the timing of behavioral sequences and, more generally, to study the origin and role of oscillatory and other forms of brain dynamics in neural systems.