Discuss the relationship between IQ, intelligence, and neural processing speed.

Question

What will be an ideal response?

Answer 1

Intelligence involves several cognitive processes that must be retrieved, combined, and related in one way or another. Thus, the speed and efficiency at which this occurs is important. Studies have shown a correlation between reaction time and IQ scores. There is also a correlation between IQ scores and neural conduction speed, which is determined by the white matter tracts (myelinated axons). In turn, white matter integrity has been shown to explain at least 10% of the variance in intelligence. In the same way, as white matter integrity decreases with age, so does intelligence.
Both white matter integrity and nerve conduction velocity determine how well information travels throughout the brain - conduction speed increases within myelinated neurons. Studies show that IQ varies among individuals with the degree of myelination. All three - myelination, speed of information processing, and intelligence - follow a curvilinear time path, increasing from childhood to maturity and then declining in old age.
Individuals with higher IQ scores use less brain energy; individuals with mild intellectual disability require 20% more neural activity to perform the same cognitive tasks as more intelligent individuals.