Is impaired dopaminergic function associated with mobility capacity in older adults?

Area of Science:

• Neuroscience
• Gerontology
• Movement Science

Background:

• Mobility is crucial for independence and declines with age, often linked to negative health outcomes.
• While musculoskeletal factors were traditionally studied, the nervous system's role in age-related mobility decline is increasingly recognized.

Purpose of the Study:

• To investigate the contribution of the basal ganglia and dopaminergic function to age-related reductions in mobility.
• To explore behavioral, genetic, and neuroimaging evidence supporting this link.

Main Methods:

• Analysis of an existing dataset using four complementary approaches.
• Examined central activation of ballistic force, catecholamine-O-methyl-transferase (COMT) genotype, movement speed as a trait, and functional connectivity within the medial orbitofrontal (mOFC) cortico-striatal network.

Main Results:

• Slower central activation of ballistic force correlated with worse mobility in older adults.
• An intermediate COMT genotype (Val/Met), affecting dopamine degradation, was associated with better mobility.
• Movement speed across tasks was a stable attribute in older adults.
• Functional connectivity in the mOFC cortico-striatal network related to mobility measures.

Conclusions:

• The basal ganglia and its dopaminergic function are implicated in age-related mobility decline.
• Deterioration in the mOFC cortico-striatal network may be a neural mechanism underlying impaired mobility in aging.