What is a correct statement about age-related changes in the nervous system?

• A. Interconnections between brain cells often prevent a loss of knowledge or skill, despite a loss of neurons
• B. The metabolic rate in the brain increases with age while oxygen consumption decreases
• C. The brain increases in size by 10% to 20% by age 80
• D. Intelligence decreases with age due to a decrease in the number of brain cells

Answer: (A)

The statement regarding interconnections between brain cells accurately reflects a phenomenon known as neural plasticity. As individuals age, there is a natural decline in the number of neurons and connections in the brain; however, the brain often compensates for this loss through the strengthening of existing connections and forming new synapses. This adaptability can help preserve knowledge, skills, and cognitive functions despite the overall reduction in neurons. Essentially, the brain retains its ability to process information and maintain cognitive abilities by relying on its existing networks and enhancing the interconnections between remaining cells.

In contrast, the other statements do not accurately represent the relationship between aging and the nervous system. The metabolic rate in the brain typically decreases with age, and while some cognitive functions may be affected, the brain does not increase in size as suggested in the statement about the aging process. Intelligence is complex and cannot be merely attributed to the number of brain cells; rather, it is influenced by a multitude of factors including the integrity of neural connections, experience, and ongoing learning.