"The archeologist's career ended in ruins": hemispheric differences in pun comprehension in autism

Appropriate interpretation of figurative language involves inferring the speaker's intent by integrating word meaning with context. In disorders like autism, understanding intended and contextual meanings in language may pose a challenge. Such difficulties are prevalent even when individuals exhibit otherwise fluent language ability (Szatmari et al., 1990). A pun is a rhetorical technique in which a speaker deliberately invokes multiple meanings through a word or phrase likely resulting in a joke. Comprehending puns may involve identifying multiple meanings of a word, embedding it in right contexts, and understanding the underlying humor. This fMRI study investigated the brain responses associated with figures of speech like puns. In the fMRI scanner, participants read sentences containing puns (e.g. To write with a broken pencil is pointless) and control sentences (literal meaning) presented in a blocked design format. The participants' task was to silently read and understand one meaning (in the literal condition) or two meanings (in the pun condition). Participants with autism, relative to typical controls, showed an increase in overall activation while comprehending sentences containing puns, particularly within the right hemisphere as well as in relatively posterior brain areas. Overall, there was reduced response in left hemisphere areas, reduced response to humor, and more distributed recruitment of regions in autism relative to control participants. We also examined the relationship between symptom severity in autism and verbal ability with brain responses to pun comprehension finding negative and positive correlations respectively. Overall, the results from the present study suggest that individuals with autism resort to altered neural routes in comprehending language in general, and figurative language in particular.