DELAYED MATCH-TO-SAMPLE PERFORMANCE IN AUTISTIC-CHILDREN

The involvement of temporal lobe structures in autism has found support in several animal and human studies. The delayed match- and nonmatch-to-sample paradigms are two tasks that are sensitive to temporal lobe and frontal lobe development and damage and may be useful in the study of autism. High- and low-functioning autistic disordered (HAD, LAD) subjects and developmental language-disordered (DLD) and mentally retarded (MR) control subjects were tested on a two stimuli matching paradigm. Both trial-unique and repeated-stimuli procedures were used. All subjects performed equally well with both procedures. Performances of HAD subjects and controls of similar nonverbal intelligence (DLD subjects) were not significantly different. The LAD group performed at chance levels and scored significantly lower than all other groups, but convarying for nonverbal intelligence elminated all signficant group differences. These results indicate successful performance on a visual recognition memory task by HAD subjects. These findings are more consistent with the possibility of temporal rather than frontal lobe dysfunction in autism. The involvement of specific temporal lobe structures, including the amygdala and hippocampus, in autism is discussed.