There's no single "highest" mental age because mental abilities peak at different times, with some skills like vocabulary rising into the 60s/70s, while quick processing peaks in the 20s/30s, and overall functioning often peaks around 55-60 before declining. The concept of "mental age" (MA) itself, derived from comparing a child's IQ to age norms, isn't used for adults; instead, modern tests use standardized scores (IQ) relative to peers, with 100 being the average.
Overall mental functioning peaked between ages 55 and 60, before beginning to decline from around 65. That decline became more pronounced after age 75, suggesting that later-life reductions in functioning can accelerate once they begin.
“Overall mental functioning peaked between ages 55 and 60, before beginning to decline from around 65,” explained author Gilles Gignac, associate professor of psychology at The University of Western Australia, in 'The Conversation'(opens in new window).
Research Results. It has been shown that scores on IQ tests actually decrease with age. This chart shows how scores on Wechsler IQ tests peak between 25 and 29 years old, then decline throughout the rest of adulthood, with a decline becoming more steep after the age of 70.
When A child of 16 years scores 75, his mental age will be: 75 = MA / 16 x 100. MA = 75 x 16 /100. MA = 12.
Snoop Dogg has publicly stated he has an IQ of 147, a score that falls into the "highly gifted" or "genius" category, much to his own surprise given his self-described average school performance (straight Cs). While this self-reported score suggests exceptional intellect, IQ tests measure specific cognitive abilities, and success in life and business (like Snoop Dogg's multifaceted career as a rapper, entrepreneur, and media personality) reflects a broader range of intelligence and skills.
A 72 IQ is considered Borderline Intellectual Functioning (BIF), falling just above the threshold for intellectual disability (usually around 70), placing it in the lower end of the spectrum (70-79) and indicating slower learning and potential needs for support in daily living, though it's not low enough for an official intellectual disability diagnosis by itself, notes Quora user. It's in the bottom few percentiles of the population, requiring more time to grasp complex concepts but not necessarily severe impairment.
No, an IQ of 97 is not considered dumb; it falls squarely in the average range (90-109), indicating typical cognitive abilities, though some tests might place it slightly below the exact midpoint of 100. An IQ score of 97 means you performed better than 42% of people, and due to the test's margin of error, your score could be anywhere from the high 80s to the mid-100s, still within normal intelligence.
Brain Development, IX: Human Brain Growth
Although total brain volume is about 95% of its adult size by the age of 5 years, various subcomponents of the brain do undergo age-related changes. In general, white matter—an indication of myelination—increases with age, while gray matter decreases with age.
Albert Einstein never took an official IQ test, so his score is an estimate, but most sources place it around 160, considered genius level, though some believe it could have been higher. This figure is based on his revolutionary scientific achievements, like the theory of relativity, rather than a standardized test. IQ tests from his era weren't as developed, and his unique thinking style makes accurate modern comparison difficult.
The last part of the brain to mature is the part that makes us human: the prefrontal cortex. It controls complex thinking, decision-making, impulse control, and personality. The neurons in the prefrontal cortex are present at birth, but they aren't fully myelinated and connected until around the age of 25.
Now we can compare Full Scale (global) IQs for adults of different ages. A clear decline is evident. The mean WAIS-IV IQ is 100 for ages 20-24 and is 99 for ages 25-44. Then it drops to 97 for ages 45-54, to 94 for ages 55-64, to 90 for 65-69, to 86 for ages 70-74 and to 79 for ages 75+.
The "2-finger test" for dementia involves an examiner showing a hand gesture (like interlocking index and middle fingers) and asking the patient to copy it, testing motor skills, visual memory, and coordination, as difficulties can signal early cognitive decline, but it's a screening tool, not a definitive diagnosis, prompting further medical evaluation. Other related tests include finger-tapping and finger-to-nose, looking for hesitation or misjudgment in movement.
Some mental skills are sharpest at different ages, with many not peaking until age 40 or later. Short-term memory is strongest at age 25, stays steady until 35, and then starts to decline. Emotional understanding peaks during middle age, while vocabulary and crystallized intelligence peak in the 60s and 70s.
Because there is no single standardized test that measures intelligence, determining the highest IQ ever will always be contentious. Bearing these caveats in mind, it is generally believed that the highest IQ score ever recorded is that of William James Sidis, who is believed to have had an IQ of between 250 and 300.
But the age of seven has been considered the age where common sense and maturity start to kick in, for centuries. In Medieval times, court apprenticeships began at age seven. Under English Common Law, children under seven weren't considered responsible for their crimes.
A new study has found that adolescence can continue until the age of 32, as humans hit four major “turning points” in brain development at the ages of about nine, 32, 66 and 83.
“The first three years are extremely, completely important for kids because that's when those neurons connect and then they're there for life,” George said. “That's a permanent infrastructure and at age 4, the brain changes. Any neurons that haven't been connected get purged out of the brain.”
Whilst there might be some truth to the idea that learning new things becomes slower after the prefrontal cortex matures, this difference is likely less significant than previously thought. With dedicated practice and the right strategies, people of all ages can continue to learn and grow.
Tom Hanks as Forrest Gump: At an early age, Forrest is deemed to have a below-average IQ of 75. He has an endearing character and shows devotion to his loved ones and duties, character traits that bring him into many life-changing situations.
Over 125 - Only 5% of people have an IQ this high. Over 130 - Only 2.5% of people have an IQ this high. Over 135 - You are in the top 1%. raw IQ score.
Studies have shown that intelligence has a genetic component, but they have not conclusively identified any single genes that have major roles in differences in intelligence. It is likely that intelligence involves many genes that each make only a small contribution to a person's intelligence.
To calculate IQ, take a person's mental age, divide it by chronological age, and then multiply that number by 100. For example, if a person has a mental age of 12 but is 10 years old, then you'd divide 12 by 10, and multiply that number by 100, which would result in an IQ of 120.
In the early 2000s another large epidemiological study reported that an IQ < 70 was observed in only 50% of children with ASD (6), while a more recent epidemiological study (7) reported a further decline toward an amount of 31% of children with ASD, that were classified in the range of cognitive impairment (IQ < 70).
The term borderline intellectual functioning describes a group of people who function on the border between normal intellectual functioning and intellectual disability, between 1 and 2 standard deviations below the mean on the normal curve of the distribution of intelligence, roughly an IQ between 70 and 85.