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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

July 22, 2026

Miniature brain models grown from patients’ cells revealed striking differences in how Alzheimer’s-related tissue responds to an antidepressant. The organoids and the particles they release could eventually guide more personalized treatments and ...
A single dose of psilocybin produced measurable changes in brain activity and possible changes in brain structure that lasted for up to a month. Participants who experienced the greatest increase in flexible, varied brain activity also reported more ...
Watching television very often in midlife may be linked to troubling brain changes decades later. In a study of about 1,700 adults, frequent TV viewers later showed smaller brain regions involved in memory, decision-making, and visual processing, ...
Researchers have uncovered a surprising culprit behind sleep loss in Alzheimer’s disease: the brain’s own immune cells. In mice with amyloid plaques, overactive microglia triggered inflammation ...
A protein called SORLA may act as a powerful defense against the toxic tau tangles involved in Alzheimer’s disease. Mice with extra SORLA had less tau accumulation, less brain atrophy, and ...
The mysterious sound known as The Hum has been reported worldwide for decades, yet its source often remains impossible to find. Researchers tested whether people who hear it have exceptional low-frequency hearing or measurable sounds produced inside ...
A low-cost antidepressant may offer new hope for people struggling with long COVID fatigue. In a randomized clinical trial involving 399 adults, fluvoxamine significantly reduced fatigue and improved quality of life compared with a placebo, making ...
Several popular sugar substitutes may not be as harmless as they seem. Adults who consumed the most artificial sweeteners showed substantially faster declines in memory and thinking, especially if they were under 60 or had diabetes. The highest ...
The Mediterranean diet may influence aging through tiny proteins produced inside the cell’s mitochondria. Older adults who followed the diet most closely had higher levels of humanin and SHMOOSE, ...
A drug originally developed for spinal cord injury may offer a fresh approach to treating Alzheimer’s disease. In mouse studies, KCL-286 repaired dangerous DNA damage, reduced inflammation, and targeted multiple disease-related pathways instead of ...
A new experimental treatment may have found a way to outsmart glioblastoma’s toughest defense: the blood-brain barrier. Researchers used sugar-coated nanoparticles to ferry genetic instructions ...
An existing constipation drug may have an unexpected new use: helping clear the "brain fog" that often lingers after depression. In a small clinical trial, people with a history of depression who took the medication prucalopride for about a week ...

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