Neurophysiological signals of working memory in normal aging

Area of Science:

• Neuroscience
• Cognitive Psychology
• Gerontology

Background:

• Working memory (WM) is crucial for cognitive function.
• Understanding age-related changes in WM neurophysiology is important for healthy aging research.

Purpose of the Study:

• To investigate how neurophysiological signals of working memory change across the adult lifespan.
• To compare brain activity patterns during a spatial WM task in young, middle-aged, and older adults.

Main Methods:

• Electroencephalography (EEG) was recorded from healthy young, middle-aged, and older adults performing spatial WM tasks of varying difficulty.
• Event-related potentials (ERPs), specifically P300 and P200 components, and EEG spectral features (theta and alpha rhythms) were analyzed.
• Groups were matched for IQ and task practice to control for confounding factors.

Main Results:

• Cognitive performance slowed with age, especially on difficult tasks.
• Advanced age was linked to decreased P300 amplitude and increased latency, and increased frontal P200 amplitude.
• Younger adults showed increased frontal midline theta rhythm with task difficulty, unlike older adults.
• Age-related changes in alpha power indicated differing recruitment of neural resources for spatial WM processing across age groups.

Conclusions:

• Normal aging is associated with alterations in fronto-parietal networks supporting spatial working memory.
• Younger adults may rely more on parietal regions, while older adults might shift towards frontal brain regions for spatial WM processing.
• These findings highlight age-related neuroplasticity and strategy adjustments in working memory.