DLD Journal F01

Researchers have hypothesized that autistics are missing core modules of the brain, critical neural tissue necessary for accomplishing various processes. In this article, we critically review the evidence supporting two such hypothesized deficits. We ask whether autistic brains lack a module for understanding the behavior of others (i.e., theory of mind) and whether they lack a module for processing faces. We illustrate that successful performance on theory of mind tasks depends on linguistic ability; therefore, it is not surprising that autistics are more likely to fail theory of mind tasks because a qualitative impairment in communication is one of the primary diagnostic criteria for autism. Similarly, we illustrate that autistics are less likely to fixate the eye region of facial photographs and that the amount of time spent fixating the eye region correlates with activation in the face processing “module”; therefore, it is not surprising that autistics are less likely to activate the putative face processing area. These illustrations cast doubt on the arguments that the autistic brain is missing the core modules responsible for understanding theory of mind and for processing faces. During the 1990s, which were deemed the “Decade of the Brain,” less invasive techniques for imaging the human brain were developed. For centuries before, we humans had wanted to look inside our heads, to see what makes us tick, and to identify commonalities that unite us and differences that distinguish us. Therefore, starting in the late 1990’s, these less invasive brain imaging techniques began to be applied to numerous special populations, including individuals with autism. The application of less-invasive brain imaging techniques to special populations has allowed testing of previously conceived hypotheses. In this article we review critically two such hypotheses: Whether the brains of autistics lack two fundamental brain modules, one that controls the ability to mentalize about other people, which is known as Theory of Mind, and one that allows the ability to recognize faces. Does the Autistic Brain Lack Core