White-matter connectivity shapes visual and semantic representations in the aging brain

Area of Science:

• Neuroscience
• Cognitive Aging
• Neuroimaging

Background:

• Aging is linked to reduced sensory processing and increased reliance on semantic memory.
• Functional MRI studies show older adults have weaker visual and stronger semantic representations.
• The underlying mechanisms of this visuo-semantic representational shift (VSRS) are not fully understood.

Purpose of the Study:

• To investigate if structural connectivity within the brain's representational network predicts age-related shifts in visual and semantic information processing.
• To explore the role of structural connectivity in mediating age-related declines in perceptual memory and supporting mnemonic representations in older adults.

Main Methods:

• Analysis of structural connectivity using neuroimaging techniques.
• Correlational analyses linking structural connectivity measures with perceptual and semantic memory performance in aging individuals.

Main Results:

• Structural connectivity was found to mediate age-related declines in perceptual representation.
• In older adults, structural connectivity supports both semantic and perceptual mnemonic representations.
• Findings observed despite typical age-related decreases in visual memory and structural connectivity.

Conclusions:

• Structural brain connectivity may be a key mechanism underlying age-related changes in perceptual processing.
• The brain's memory system demonstrates adaptability with age, potentially through preserved or altered connectivity.
• Understanding these neural mechanisms can inform interventions for cognitive aging.