AGE-RELATED-CHANGES IN COGNITIVE ERPS OF ATTENUATION

This investigation explored developmental changes in passive and effor tful components of ERPs associated with a visual attention task in chi ldren, adolescents, and adults. The task was a 'go-go' version of a co ntinuous performance task, coupled with a passive attending phase in w hich the subjects merely watched the stimuli of the task. The three ag e groups featured a constellation of EXP components that shared the sa me general morphological appearance and distribution, but differences were seen with respect to latencies and amplitudes. Consistent with ot her studies, there was an inverse relationship with respect to age and peak latencies of the major passive and effortful components. With re spect to peak amplitudes, however, the most impressive changes with ag e were observed in the passive processing components. For example, the P150 and P250 components presented greater amplitudes in children, wh ereas the N200 component presented its greatest amplitude in adults. W hile passive in the sense that their appearances were independent of t he 'decision-making' process, these components were found to be upward ly adjustable by effort. The late positive component was found to be a combination of a passive P350 and an effortful P450. The P350 compone nt was judged to be largely passive in character as it was well develo ped in subjects of all age groups when passively attending to the visu al stimuli. There was no marked amplitude difference between the child and adult P450 components, but the components peaked in amplitude lat er in the children. Finally, the children's ERPs featured a distinct f rontal negativity (FN) that was present in the Passive phase, but grea tly enhanced during the Effortful phase. This study, as have many othe rs, showed that there are reliable developmental changes in the compon ents of visual ERPs. Therefore, the characteristics of the various com ponents of cognitive ERPs may be effective markers of neurodevelopment al status, especially of those neuronal systems vital to attentional p rocessing and effort regulation.