For a study, the researchers used eye-tracking to analyze attention and recognition memory in Phelan-McDermid syndrome (PMS), a rare genetic disorder characterized by intellectual disability, motor delays, and a high likelihood of comorbid autism spectrum disorder (ASD). Social deficits represented a core feature of ASD, including decreased propensity to orient to or showed preference for social stimuli. On measures of attention, the PMS group with a comorbid ASD diagnosis spent less time viewing the social images than non-social images; the rate of looking back and forth between images was lowest in the iASD with ID group. Furthermore, while all groups demonstrated intact recognition memory when novel non-social stimuli were initially presented (pre-switch), participants with PMS showed no preference during the post-switch memory presentation. In iASD, the group without ID, but not the group with ID, showed a novelty preference for social stimuli. Across indices, individuals with PMS and ASD performed more similarly to PMS without ASD and less to the iASD group. Researchers demonstrated further contrast in attention and memory for social stimuli in ASD and provided distinctions between iASD and PMS.