Abstract
Does aging affect neural processing similarly across cognitive tasks or does it target specific cognitive processing mechanisms? Frequent findings of increased latency and reduced amplitude in older adults suggest the possibility of a general mechanism. However, no study has tested this hypothesis directly by comparing processing within the same individuals across multiple tasks. In our study, older (ages 60-85) and younger (ages 18-30) adults participated in four tasks (CORE; Kappenman et al., 2020) while EEG was collected: face processing (N170; one-back for faces, cars, scrambled faces, and scrambled cars), attention and categorization (P3; visual odd-ball), semantic processing (N400; word-pair semantic judgment), and error processing (ERN; flanker task). Each group had 17 participants with complete data across all tasks. Results showed differential age-related condition effects for different tasks. For the N170, older and younger adults showed similar amplitude differences between faces and cars at P07/P08 electrodes. For the ERN, no significant age-related differences were found for error versus correct response amplitude differences at central electrodes. In contrast, age-related differences were found for the P3 and N400 ERPs at centroparietal electrodes in terms of smaller condition amplitude differences and less focal distributions of neural responses. Specifically, older adult amplitudes differed from younger adults for the target, but not the standard, condition (P3) and for the related, but not the unrelated, word-pair conditions (N400). An age by task interaction of standardized difference wave amplitudes confirmed significant age-group differences for the P3 and N400, but not for the N170 and ERN. Thus, aging does not affect neural processing similarly across these four cognitive tasks within individuals.