To understand the neurobiology behind autism, we need data at the cellular level. This is difficult to come by in humans, as the data are typically limited to analyses of postmortem tissue, or data from animal models. However, there is an opportunity to obtain physiological data directly from neurons in the human brain in a clinical setting — through depth electrode and surface grid monitoring in neurosurgical patients for the treatment of medically refractory epilepsy. This project involves several hospitals where such data can be recorded.
The significance of recording from the brain in people with autism is high, because this would be the first opportunity to investigate data at the neuronal level. What are the basic electrophysiological response properties in autism? What are evoked responses to stimuli such as faces, which are known to be processed abnormally in autism? Such data can be compared with data obtained from fMRI studies as well.
Furthermore, the neuronal data could eventually be linked to synaptic, molecular and genetic data that underlie abnormal physiology. Ralph Adolphs and his colleagues at the California Institute of Technology aim to begin with a characterization of the basic electrical properties of neurons: Do their firing rates and waveforms appear normal?
Next, the researchers hope to present a standardized series of stimuli at all the participating hospitals in order to measure evoked responses to a range of stimuli, including faces, landscapes and objects of special interest. This portion of the project is intended to survey the overall response profiles of neurons. Finally, the investigators plan to examine, in detail, the responses to faces. Taken together, the studies aim to provide the first direct measures of neuronal responses from the brain in individuals with autism.