The effects of memory trace strength on eyewitness recall in children with and without intellectual disabilities

Children with mild moderate intellectual disabilities (ID) were compared with typically developing peers of the same chronological age (CA) on an eyewitness memory task in which memory trace strength was manipulated to examine whether increased memory trace strength would benefit those with ID more than those without ID. No evidence was found for this claim or for the notion that different mechanisms are implicated in memory processes for children with ID versus CA controls. Fuzzy-trace theory was also used to contrast question types that probed verbatim memory versus gist memory. Manipulations of trace strength, when used with immediate recall (to reduce the impact of decay), were predicted to improve verbatim memory more than gist memory. The results broadly supported the predictions. Performance was not improved in the stronger trace strength condition on measures of recall that tapped gist memory (e.g., open-ended recall), whereas performance was significantly better in the stronger trace strength condition on two of the three measures of recall that tapped verbatim memory (i.e., closed misleading questions, open-ended specific questions). Differences in performance between the groups were quite marked on several question types, supporting previous findings that those with ID have certain vulnerabilities as potential witnesses compared with peers of the same CA.