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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

March 18, 2026

Your morning coffee or tea could be quietly supporting your brain health. A long-term study found that moderate consumption of caffeinated coffee or tea was linked to an 18% lower risk of dementia and better cognitive performance over time. The ...
Early life stress may set the stage for long-term digestive problems by disrupting the gut-brain connection. Studies in both mice and thousands of children found links to symptoms like pain, constipation, and IBS. Scientists discovered that ...
A key Alzheimer’s drug has finally revealed its secret. Researchers discovered that lecanemab works by activating the brain’s immune cells—but only through a specific part of the antibody called the Fc fragment. This piece acts like a trigger, ...
Researchers have identified a surprising brain pattern that may help explain why people with ADHD often struggle to stay focused. Even while awake, their brains can slip into brief episodes of “sleep-like” activity during demanding tasks. These ...
A new UCLA Health study suggests that long-term exposure to the pesticide chlorpyrifos may dramatically raise the risk of Parkinson’s disease. Researchers found that people living in areas with sustained exposure had more than 2.5 times the ...
A protein tied to ALS and dementia may have a much bigger role in disease than scientists realized. Researchers found that TDP43 controls a key DNA repair process, but when the protein becomes ...
Tiny plastic particles may be quietly threatening brain health. New research suggests microplastics—now widely found in food, water, and even household dust—could trigger inflammation and damage ...
Researchers have discovered a surprising change in how cells produce energy in people with depression. Brain and blood cells in young adults with major depressive disorder produced more energy molecules at rest but had trouble increasing energy ...
A new study suggests Alzheimer’s disease may be detectable through subtle shape changes in proteins found in the blood. Researchers discovered that structural differences in three blood proteins closely track the progression of the disease. By ...
Scientists have developed a promising new approach to treating Alzheimer’s disease by turning ordinary brain cells into powerful plaque-clearing machines. Instead of requiring frequent antibody infusions like current therapies, the experimental ...
THC doesn’t just blur memories—it can create new ones that never happened. In a controlled experiment, cannabis users were much more likely to recall words that were never shown and struggled with tasks like remembering to do something later. ...
A new brain-imaging study has revealed how ketamine produces its fast antidepressant effects in people with treatment-resistant depression. Researchers tracked changes in a critical brain receptor that helps neurons communicate and found that ...

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