Learning and self-regulation of slow cortical potentials in older adults.

Two groups of subjects, aged 20-28 and 50-64, respectively, matched for health status and verbal abilities, learned to control their slow cortical potentials (SCP) in a feedback paradigm by producing, on command, SCP shifts in either positive or negative direction. Both groups were able to differentiate significantly between the positivity task and the negativity task, with the differentiation score being only slightly (and not significantly) lower in older than in younger subjects. In all conditions, however, significantly more negative brain responses were obtained in older than in younger subjects.