Syllable breaking after telencephalic cooling unveils the presence of nonlinearly interacting timescales in birdsong motor pathway

MATÍAS A. GOLDIN; LEANDRO M. ALONSO; JORGE A. ALLIENDE; FRANZ GOLLER; GABRIEL B. MINDLIN

Lyon

Congreso; 11th Neuroscience Congress; 2013

Societé Française des Neurosciences

P { margin-bottom: 0.21cm; direction: ltr; color: rgb(0, 0, 0); line-height: 115%; text-align: left; widows: 2; orphans: 2; }P.western { font-family: "Calibri",sans-serif; font-size: 11pt; }P.cjk { font-family: "Calibri",sans-serif; font-size: 11pt; }P.ctl { font-family: "Calibri",sans-serif; font-size: 11pt; } We study the emergence of complex behaviors in the birdsong motor pathway. Stereotyped motor activities may originate in precise telencephalic control or may arise from its interaction with downstream nuclei. Here we present a minimalistic dynamical model that accounts for the diverse respiratory patterns found in the song of birds. Air-sac pressure gestures are obtained as the output of an excitatory-inhibitory non-linear interaction between two neuron populations, driven by an upstream telencephalic instruction. Considering a simple and precise time pattern, we can build a map of frequency and amplitude of this instruction. This picture, called bifurcation diagram, accounts for most of the syllabic morphologies found in canaries (Serinus canaria). It also illustrates patterns of subharmonicity and bifurcation, which makes predictions for how cooling of HVC should affect song. We then tested these predictions by bilateral cooling of the telencephalic nucleus HVC in canaries. Cooling is thought to reduce the frequency of HVC motor output. Cooling resulted in song and subsyringeal air sac pressure patterns that matched the predictions of the model: syllables were stretched initially and syllable breaking occurred upon further cooling.