Along with cognitive decline, aging can lead to which of the following changes in the nervous system?

Aging is associated with various physiological changes in the nervous system, one of which is decreased synaptic plasticity. Synaptic plasticity refers to the ability of synapses to strengthen or weaken over time, in response to increases or decreases in their activity. This process is crucial for learning, memory, and overall cognitive function. As individuals age, the mechanisms that support synaptic plasticity tend to decline, resulting in less flexibility in synaptic connections. This is partly due to structural changes in the brain, such as a reduction in the number of synapses and changes in neurotransmitter functioning.

In contrast, the other choices describe processes that either do not typically improve with age or are not consistent with the established understanding of age-related changes in the nervous system. For example, reflexes may slow down rather than enhance with age, neurotransmitter efficiency generally decreases, and brain elasticity, or neuroplasticity, might also diminish. Therefore, the decreased synaptic plasticity is a key characteristic of the aging nervous system, reflecting the difficulties often faced in cognitive tasks and memory associated with older age.