Young children are diagnosed with autism when they fail to develop language and have social difficulties and overly repetitive behaviors. To understand the biological bases of autism and develop treatments for these problems, basic information about how the brain produces language must be known. Currently, we have insufficient knowledge about the molecular and cellular events that underlie language development. Since we would not want to do invasive experiments with humans, we need to develop animal models for autism. However, traditional laboratory animals, such as rats, mice, and non-human primates, are not vocal learners. Fortunately, songbirds are vocal learners and thus offer the potential to identify socially sensitive brain mechanisms for vocal learning. Vocal learning in songbirds shares key aspects with human speech learning, namely: (1) it happens during critical developmental windows; (2) it occurs within discrete regions of the brain; (3) it depends on social interactions. Importantly, one can conduct molecular and behavioral experiments on songbirds.
Our proposed experiments will use songbirds to investigate the role of a molecule known as Cntnap2, an autism susceptibility gene. Variations of this molecule have been linked to autism and to other developmental disorders in which language is affected. We know that Cntnap2 gene expression is expressed in a strikingly similar pattern in human and songbird brains that is distinct from patterns observed in rodents. Now we want to find out how it works in songbirds with the goal of applying these findings to humans. The results of this work will help to establish songbirds as one of a panel of animal models for testing therapeutic interventions for ASD, and, specifically, to detect their efficacy in improving socially learned vocal communication. While this research is of a basic nature, within the next 10 years we expect it to assist in formulating novel approaches to improve social interactions and speech learning, and thus the quality of life, of autistic children.
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