Neurobiology of vocal creativity

Vocal communication is a critical part of our everyday lives, facilitating social exchange. At the center of this process is lexical retrieval, a process in which an appropriate word can be selected from a mental dictionary (lexicon) to express a specific concept. Lexical retrieval is affected in many communication disorders, including aphasia following stroke, neurodegenerative disorders like Parkinson’s disease, and age-related dementia. How the brain can flexibly retrieve concepts to compose vocal messages is poorly understood, in part because of the lack of an appropriate animal model. To address this need, our laboratory has recently been studying the budgerigar, a parrot species that can rapidly mimic a range of environmental sounds, including human speech. We found a representation of vocal sounds in a key forebrain center with functional properties analogous to vocal production centers in humans. We are now expanding this discovery to understand how individual ‘words’ are formed in the parrot brain, what they mean, and how they can be transferred to others. These efforts are part of a comparative approach that leverages a range of animal models to gain a window into different aspects of human spoken communication in health and disease.