Electrophysiological Studies of Gating, Timing and Connectivity in Autism

Although autism is defined by three types of behavioral impairments, findings in autism research are pointing toward widespread network signal coordination or connectivity problems as underlying what we see as autism – various parts of the brain do not synchronize normally. Reduced connectivity has been found using methods that are better at locating things in space than in time; for example, functional MRI can give us pictures of where the brain activates but is not useful for revealing the sequence of activation, because it cannot register changes that happen in intervals shorter than a second. Electroencephalography (EEG) on the other hand has a time resolution at the millisecond level-more than a thousand times more fine-grained time resolution than can be achieved with MRI. To get the most detailed measurements of short range and long range coordination it is necessary to use a high-density electrode array which covers as much of the entire scalp as possible with electrodes that are closely spaced. To do so, the NLM Family Foundation supported the purchase of a 128-lead EEG machine to upgrade the investigator’s capacity from her 32 lead system which limits the measurements she can make. The investigator believes that electrophysiological measures are key to showing the ways that brain functional changes are related to sensorimotor, perceptual, learning and behavioral differences in autism.