| dc.description.abstract | Human speech production and grammatical organization of language is controlled primarily by the left hemisphere of brain. Broca's area is a specialized area in the left frontal cortex that is responsible for our ability to construct grammatically correct sentences. Songbirds are studied as an animal model for understanding human language production. Our research sought to explore whether the neural control of birdsong syntax of the Bengalese finch is also lateralized; if so, the Bengalese finch would provide a good animal model to further study syntax generation in humans. To investigate this question, we recorded the birdsongs of 8 different Bengalese finches. Then, the HVC (letters used as proper name) brain region, a brain area thought to control birdsong syntax, was lesioned in either the right or the left hemisphere for each bird. Birdsong was then recorded for five months following the surgery. Song syllables were coded and analyzed to measure the syntactic structure of the song. The birdsongs were grouped into a right lesion group and a left lesion group, and they were compared based on three measures of song syntax; sequence stereotypy, sequence consistency, and sequence linearity were measured at each time point. HVC lesion initially disrupted song syntax, but song syntax recovered. There was no significant difference between the left and right lesion groups. When looking at individual time points, the right lesion group seemed to initially lose more syntactic control four days after surgery, but overall, the trends between the two groups are relatively similar. Our results suggest that the HVC control of Bengalese finch song syntax is not lateralized as it is in human speech. Our results show that HVC does play a role in the syntactic structure of birdsong, but the recovery of song syntax following brain injury suggests other areas of the brain contribute to the generation of the Bengalese finch song syntax. | |
