Contributions of the Frontal and Medial Temporal Lobes to Recognition Memory Performance in Young Adults

Previous research with older adults suggests that the frontal lobes and the medial temporal lobes play an important role in recognition memory. The goal of this study was to investigate the impact of high/low frontal lobe and medial temporal lobe status in younger adults’ recognition memory performance. Twenty-four college-aged women completed a neuropsychological battery and a recognition memory task. Behavioral and event related potential (ERP) data were collected during the recognition memory task. The results indicated that, in young adults, the medial temporal lobe showed the greatest contribution in both the old/new effect and in subsequent recollection and familiarity responses, with frontal lobe contributing minimally to either the old/new judgment or the recollection and familiarity judgment. In summary, though the frontal lobe plays a great role in the differentiation of recollect/familiar responses in older adults, we do not see this pattern in young adults. This suggests a developmental change occurring in the frontal lobe in older adulthood, where the frontal lobe assumes a bigger role in judgments succeeding the old/new judgment, either due to compensatory mechanisms or dedifferentiation.