Cognitive Performance in Older Males is Associated with Growth Hormone Secretion

Decreases in GH secretion with age may contribute to cognitive changes associated with aging. We evaluated the relation between GH secretion and cognition in elderly males by assessing correlations between GH secretion and performance on cognitive tests in conjunction with recording of event-related potentials (ERPs) to assess underlying neurophysiological mechanisms. GH secretion of 17 elderly male participants was assessed by a GHRH-GHRP-6 test. Standardized neuropsychological tests were used to assess cognitive function. EEG/ERPs were recorded to assess on-line electrocortical correlates of sensory-cortical processing and selective attention. GH secretion was significantly correlated with target detections and speed of responding in the selection-potential task. Furthermore, GH peak was significantly correlated with the performance letter-digit span test. The present data confirm that cognitive performance in elderly males is associated with GH secretion, with respect to target detection and speed of responding in conditions of selective attention, short-term memory, and basic processing speed.