Fatigue, depression, and cognitive performance among aged persons

Previous research by the authors has suggested that older persons who are depressed may be especially susceptible to the effects of fatigue in situations where multiple skills are assessed. The impact of fatigue and the effects of depression on cognitive performance have long been recognized as impediments to the accurate assessment of competence in the aged. To investigate such influences, data were gathered from 72 aged persons who had been screened for depression and assigned to one of three conditions varying in effort and the fatigue-inducing nature of the tasks to be solved. Results suggested depressed persons were more prone to fatigue. For measures of both active and passive short-term memory, depression and task effort impacted on performance. Such effects were considerably weaker for measures of intelligence.