Fluid Intelligence Fluid intelligence is tied to biology.
Fluid intelligence is important to psychologists as it relates to the study of aging.
There is ongoing intense debate among psychologists as to whether or not intelligence declines with aging. This is because of the physiological changes that accompany aging. The development of CNS structures is exceeded by the rate of CNS breakdown. The psychology of aging theory, research, and interventions . Organization of data on life-span development of human abilities.