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The effects of attention were assessed on novelty P3 amplitude and scalp distribution elicited by environmental sounds in young and elderly volunteers who participated in either actively attended or ignored oddball conditions. For the young, novelty P3 amplitude decreased with time on task during both attend and ignore sequences. Amplitude decrements were greatest at frontal sites during the attend condition, but at all sites during the ignore condition. A reliable amplitude decrement was not observed for the elderly in either the attend or ignore oddball series. The data suggest that attention differentially activates multiple generators that contribute to scalp-recorded novelty P3 activity. The lack of novelty P3 habituation seen in the elderly is consistent with changes in frontal lobe function as age increases.

Brief nontonal sounds are used in electrophysiology in the novelty oddball paradigm. These sounds vary in the brain activity they elicit and in the degree to which they can be identified, named, and remembered. Because ease of sound identification may influence sound processing, naming and conceptual norms were determined for 100 sounds for 77 young adults (Experiment 1). Naming ability decreases in normal and pathological aging. Therefore, norms were also derived for older adults (Experiment 2) and for probable Alzheimer's disease patients (Experiment 3). With respect to the young adults, perseverative naming behavior increased in these groups, and sound and picture naming performance were correlated. In Experiment 4, the sound-naming performance of children aged 5-6, 9-11, and 14-16 years was compared. Name and conceptual agreements improved with age, whereas perseverative behavior decreased. These normative data should be useful in guiding sound selection in future studies and help clarify the relationships between sound naming and other variables, including direct and indirect memory performance.

Cognitive control involves adjustments in behavior to conflicting information, develops throughout childhood and declines in aging. Accordingly, developmental and age-related changes in cognitive control and response-conflict detection were assessed in a response-compatibility task. We recorded performance measures, pre-RT activity and medial frontal negativity (MFN), sequentially-occurring, putative ERP indices, respectively, of cognitive control and response-conflict detection. When response conflict reached the highest levels by requiring incompatible responses on post-error trials, children and older adults showed the greatest performance decrements. ERPs indicated that young adults implemented control (pre-RT) and detected the increased conflict (MFN) only when that conflict was at the highest levels, whereas children and older adults did so at lower levels (e.g., post-error, compatible responses). Consequently, the developmental and age-related performance decrements observed here may be due to the undifferentiated and inefficient manner in which children and older adults recruited the processes associated with cognitive-control and response-conflict detection.