Distinct age-related brain activity patterns in the prefrontal cortex when increasing cognitive load: A functional...

Area of Science:

• Neuroscience
• Cognitive Psychology
• Aging Research

Background:

• Distinct brain activity patterns observed between younger and older adults correlate with cognitive performance.
• Older adults often show over-recruitment of bilateral brain regions, interpreted as compensation, particularly at lower cognitive loads.

Purpose of the Study:

• To investigate age-related differences in prefrontal cortex (PFC) activity and cognitive performance.
• To examine the compensatory mechanisms in older adults using functional near-infrared spectroscopy (fNIRS) during N-back tasks.

Main Methods:

• Recruited 27 young adults (18-27 years) and 31 older adults (64-84 years).
• Utilized functional near-infrared spectroscopy (fNIRS) to measure PFC activity during single and dual N-back tasks.
• Employed channel and region of interest analyses for robust fNIRS data interpretation.

Main Results:

• Older adults showed more bilateral PFC activation than young adults across all tasks.
• Brain activity increased in older adults from low to high cognitive load conditions.
• Performance differences were noted between task loads, with age-related differences in reaction times but not accuracy.

Conclusions:

• Findings support the compensatory recruitment theory in older adults' PFC to maintain cognitive performance.
• Evidence suggests that compensatory mechanisms are present even at higher cognitive loads in older adults.
• fNIRS is a sensitive tool for characterizing adaptive cortical changes in healthy aging.