Cognitive Difficulty Intensifies Age-related Changes in Anterior Frontal Hemodynamics: Novel Evidence from Near-infrared Spectroscopy.
Alongside age-related brain deterioration, cognitive functioning declines, particularly for more demanding tasks. Past research indicates that, to offset this decline, older adults exhibit hemodynamic changes consistent with recruitment of more anterior brain regions. However, the nature of the hemodynamic changes remains unclear. To address this knowledge gap, we used near-infrared spectroscopy in 36 young adults (aged 18-30 years) and 36 older adults (aged 60-72 years) to assess anterior frontal hemodynamic responses to engagement in three cognitive tasks of increasing difficulty. Behavioral results for all three tasks confirmed aging deficits (evidenced by slower reaction times and reduced accuracy rates) that progressively increased with task difficulty. Hemodynamic results showed opposing effects in young versus older adults, with oxygenated and total hemoglobin decreasing in young but increasing in older adults, particularly during the harder tasks. Also, tissue oxygenation increased only in older adults during the harder tasks. Among the older adults only, anterior frontal hemodynamic changes correlated with better cognitive performance, indicating that they were compensatory in nature. These findings provide novel evidence of age-related anterior frontal hemodynamic changes that intensify with cognitive demands and compensate for performance deficits.
['Bierre|Kirstin L|KL|', 'Lucas|Samuel J E|SJ|', 'Guiney|Hayley|H|', 'Cotter|James D|JD|', 'Machado|Liana|L|']
D000293:Adolescent D000328:Adult D000367:Age Factors D000368:Aged D003071:Cognition D005260:Female D005625:Frontal Lobe D006439:Hemodynamics D006801:Humans D008297:Male D008875:Middle Aged D019265:Spectroscopy, Near-Infrared D055815:Young Adult
Aging Task difficulty Cerebral hemodynamics Executive function NIRS