Nerve Conduction Velocity (NCV): The Hardware Limit
Human cognitive response speed is not merely an athletic metric; it depends partly on how quickly the central nervous system transmits and processes information. One relevant factor is Neural Conduction Velocity (NCV). Electrical signals travel along an axon — the long projection of a nerve cell. Their speed depends on factors including the axon's diameter and the thickness of its myelin sheath. Myelin insulates the axon, allowing the signal to "jump" between nodes of Ranvier through saltatory conduction, reaching speeds of up to 120 meters per second.
Hick's Law and Decision Latency
Known in psychology as Hick's Law, reaction time generally increases logarithmically as the number of choices increases. Each doubling of equally likely choices adds one "bit" of information. Our assessment asks you to rate your own reaction speed; it does not measure response latency.
Reaction Time and General Intelligence (g-factor)
Arthur Jensen and other psychometricians studied the negative correlation between measured reaction time and general intelligence (g). Faster reaction times are associated with higher intelligence test scores on average, but reaction time alone cannot establish a person's intelligence or neurological efficiency.
Response Time Variability (RTV) — The Hidden Indicator
Often, the variability of your responses can be more informative than your single fastest response. Reaction times naturally vary and can be affected by attention, fatigue, the task and the device used. Greater variability alone cannot identify ADHD or establish whether a person's neurochemical balance is altered.
Environmental Impact and Biological Rhythms
Your cognitive speed is not fixed. It fluctuates partly with your circadian rhythm. Reaction speed can vary throughout the day and is often slower during the biological night, although timing varies between individuals. Illness, fatigue and other factors can also affect how quickly you respond.