RESUMO
BACKGROUND AND PURPOSE: Cognitive decline is a function of normal aging; however, the effect of age on various domains is differential. This study examined the effect of age on verbal fluency and showed how speed of processing modifies fluency performance in healthy older adults compared to younger individuals. METHODS: Three age groups, 62 young (17-40 years), 30 middle-aged (41-59 years), and 38 older adults (60-78 years), were studied using the Controlled Oral Word Association Test, National Adult Reading Test, and speed-of-processing composite score. The study examined the effect of age on fluency before and after controlling for processing speed and intelligence quotient. RESULTS: The young group performed better than the older group on category fluency as measured by animal category (p < .001) and on processing speed composite score (p < .001). However, the older group performed better than the young group on the National Adult Reading Test (p < .05) and on letter fluency after controlling for the decline in processing speed (p < .05). Processing speed had a significant effect on both category and letter fluency (p < .01) in older adults. CONCLUSIONS: This study suggests that aging adversely affects some but not all cognitive domains and that age-related decline in processing speed contributes to age-related changes in fluency.
RESUMO
Nicotinic acetylcholine receptor stimulation is a potential target for controlling symptoms in several psychiatric disorders. Galantamine is a cholinesterase inhibitor that can modulate the nicotinic receptor sites. In this study, we examined the effect of galantamine on the quantitative EEG in patients with major depression. Twenty patients were included in a randomized, double-blinded, placebo-controlled trial. Patients received galantamine (8 mg/day for 4 weeks then 16 mg/day for another 4 weeks) or placebo for eight weeks. Quantitative EEG using the international 10 to 20 configuration, 9 minutes of resting, eyes closed, and eyes open was done before and after the study period. Nineteen patients completed the study and their data were included in the final analysis. The results showed that galantamine compared with placebo reduced absolute band power that was statistically significant (using multivariate analysis of variance) for beta wave [F(1,17) = 2.48, P = 0.03]; the between-subject effect was significant on the left and right posterior, and left central regions. The multivariate analysis of variance model for alpha was not significant [F(1,17) = 1.07, P = 0.43]. We suggest that the reduction in absolute power after galantamine administration could be a sign of brain activation as a result of modulation of neurotransmitter release. We recommend the initiation of a larger study to confirm our findings and help in understanding the neuropathology of major depression.
