Theta power is reduced in healthy cognitive aging

Area of Science:

• Neuroscience
• Cognitive Psychology
• Gerontology

Background:

• Cognitive aging is associated with changes in brain activity.
• Electroencephalography (EEG) measures electrical activity in the brain.
• Theta power, particularly frontal midline theta (fmtheta), is linked to cognitive processes.

Purpose of the Study:

• To investigate the effects of healthy cognitive aging on EEG theta power during a word recognition task.
• To compare theta power differences between young and older adults.
• To explore whether theta power is a more sensitive marker of cognitive aging than task performance.

Main Methods:

• Participants: 14 young (mean age 21.9) and 14 older (mean age 68.4) adults.
• Task: Modified Sternberg word recognition task.
• Measures: EEG theta power (4.9-6.8 Hz) during task performance and resting state; recognition accuracy.

Main Results:

• Older adults exhibited significantly lower theta power during task retention and recognition intervals compared to young adults.
• The theta power difference was most pronounced at the fronto-central midline electrode.
• A smaller decrease in theta power was observed in resting EEG, and recognition accuracy showed a non-significant decrease in older adults.

Conclusions:

• Task-specific frontal midline theta (fmtheta) power may serve as a more sensitive neurophysiological marker of cognitive aging than behavioral measures.
• Findings support the role of brain networks involving the anterior cingulate cortex in cognitive aging, as fmtheta is primarily generated there.