Dorsolateral prefrontal lobe activation declines significantly with age--functional NIRS study.

Dorsolateral prefrontal cortex (DLPF) activation in response to cognitive paradigms engaging working memory was quantitatively evaluated using functional near infrared spectroscopy (fNIRS) in cognitively normal individuals across the age spectrum (20-90 years; 8 females, 52 males). DLPF activation score (DAS) demonstrated a significant decline (r(2) = -0561, p < 0.05) as a function of age. The study indicates that blood flow response associated with DLPF activation declines as a function of age in cognitively normal individuals and that fNIRS can be used as a convenient, portable tool for assessing such activation.