Autism spectrum disorders represent a major cause of disability both in the U.S. and worldwide, but medical treatments are nearly nonexistent. Many major pharmaceutical companies have closed down psychiatry-related drug development programs.

Among the reasons for this withdrawal is a lack of understanding of the neural basis of complex behavioral states and symptoms, including social dysfunction. This lack of information impedes the identification of targets for treatment.

Karl Deisseroth and his colleagues at Stanford University in California are setting out to find ways to observe fine details of symptomatic brains without losing larger-scale neural circuit perspective. They plan to apply a new suite of technologies called CLARITY to autism spectrum disorders. In CLARITY, the lipids of an intact brain are replaced with hydrogel components, providing both optical and molecular access to the brain.

CLARITY is suitable for postmortem studies of brains from people who had autism, as it allows researchers to visualize cellular components of brain tissue and to identify neurons and their interconnections over large brain volumes. It also provides distinct information about the three-dimensional and topological morphology of traced neurons. The resulting information from this project may help shed light on the structural underpinnings of autism.