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Reference Terms
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Intelligence quotient

An intelligence quotient or IQ is a score derived from a set of standardized tests developed to measure a person's cognitive abilities ("intelligence") in relation to their age group. An IQ test does not measure intelligence the way a ruler measures height (absolutely), but rather the way a race measures speed (relatively). Modern IQ tests produce scores for different areas (e.g., language fluency, three-dimensional thinking, etc.), with the summary score calculated from subtest scores. The average score, according to the bell curve, is 100.

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Mind & Brain News

January 15, 2026

Spikes in blood sugar after eating may be more dangerous for the brain than previously thought. In a massive genetic study, people with higher post-meal blood sugar had a much greater risk of Alzheimer’s disease. The effect couldn’t be explained ...
A massive international brain study has revealed that memory decline with age isn’t driven by a single brain region or gene, but by widespread structural changes across the brain that build up over time. Analyzing thousands of MRI scans and memory ...
Despite longstanding guidelines, many dementia patients are still prescribed brain-altering medications that can raise the risk of falls and confusion. A new study shows that while prescribing has decreased overall, people with cognitive impairment ...
Researchers have discovered a brain activity pattern that can predict which people with mild cognitive impairment are likely to develop Alzheimer’s disease. Using a noninvasive brain scanning technique and a custom analysis tool, they detected ...
A large review of studies suggests that exercise can ease depression about as effectively as psychological therapy. Compared with antidepressants, exercise showed similar benefits, though the evidence was less certain. Researchers found that light ...
Teens who sleep in on weekends may be giving their mental health a boost. A new study found that young people who made up for lost weekday sleep had a significantly lower risk of depression. While consistent sleep is still best, weekend catch-up ...
A familiar mouth bacterium best known for causing cavities may also be quietly influencing the brain. Scientists found that when this microbe settles in the gut, it produces compounds that can travel through the bloodstream and harm neurons involved ...
Many people with multiple sclerosis struggle with balance and coordination, and this study uncovers a hidden reason why. Researchers found that inflammation in the brain disrupts the energy supply of vital movement-controlling neurons. As their ...
A long-running debate over Tamiflu’s safety in children may finally be settled. Researchers found that influenza, not the antiviral medication, was linked to serious neuropsychiatric events like seizures and hallucinations. Even more striking, ...
Nearly all women in STEM graduate programs report feeling like impostors, despite strong evidence of success. This mindset leads many to dismiss their achievements as luck and fear being “found out.” Research links impostorism to worse mental ...
New research shows gut bacteria can directly influence how the brain develops and functions. When scientists transferred microbes from different primates into mice, the animals’ brains began to resemble those of the original host species. Microbes ...
Researchers compared a traditional Chinese medicine, Yueju Pill, with a standard antidepressant and found both reduced depression symptoms. However, only Yueju Pill increased a brain-supporting protein associated with mood improvement. Brain imaging ...

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