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Left-handed
A person who is left-handed primarily uses his or her left hand, more so than the right hand; a left-hander will probably use the left hand for tasks such as personal care, cooking, and so on. Writing is not as precise an indicator of handedness as it might seem, because many left-handed people write with their right hand but use their left hand for other tasks. Approximately 8 to 15% of the adult population is left-handed. Studies indicate that left-handedness is more common in males than females. Left-handedness, in comparison to the general population, also appears to occur more frequently in identical twins, and several groups of neurologically disordered individuals (people suffering from epilepsy, Down's Syndrome, autism, mental retardation, dyslexia, etc.)There have been many famous left-handed people, and the associated right brain hemisphere that is said to be more active in left-handed people has been found in some circumstances to be associated with genius and is correlated with artistic and visual skill.
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Mind & Brain News
December 12, 2025
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Dec. 10, 2025 A Virginia Tech study shows that ultra-processed foods may influence adolescents differently from slightly older young adults. Participants aged 18 to 21 ate more at a buffet and snacked even when not hungry after two weeks on an ultra-processed ...
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Dec. 10, 2025 Researchers discovered that unusually high temperatures can hinder early childhood development. Children living in hotter conditions were less likely to reach key learning milestones, especially in reading and basic math skills. Those facing ...
Dec. 9, 2025 BISC is an ultra-thin neural implant that creates a high-bandwidth wireless link between the brain and computers. Its tiny single-chip design packs tens of thousands of electrodes and supports advanced AI models for decoding movement, perception, ...
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Dec. 9, 2025 Researchers discovered that a tiny structural feature of the enzyme GPX4 helps keep neurons safe. A rare mutation removes this protection, allowing harmful molecules to damage cell membranes and trigger early dementia. Mouse and cell studies showed ...
Dec. 8, 2025 Deep-brain recordings showed that Mounjaro and Zepbound briefly shut down the craving circuits linked to food noise in a patient with severe obesity. Her obsessive thoughts about food disappeared as the medication quieted the nucleus accumbens, the ...
Dec. 8, 2025 Researchers have built a fully implantable device that sends light-based messages directly to the brain. Mice learned to interpret these artificial patterns as meaningful signals, even without touch, sight, or sound. The system uses up to 64 ...
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Dec. 6, 2025 Scientists uncovered a surprising four-layer structure hidden inside the hippocampal CA1 region, one of the brain’s major centers for memory, navigation, and emotion. Using advanced RNA imaging techniques, the team mapped more than 330,000 genetic ...
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Dec. 10, 2025 Researchers uncovered how shifting levels of a brain protein called KCC2 can reshape the way cues become linked with rewards, sometimes making habits form more quickly or more powerfully than ...
Dec. 10, 2025 Humans don’t just recognize each other’s voices—our brains also light up for the calls of chimpanzees, hinting at ancient communication roots shared with our closest primate relatives. ...
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Dec. 4, 2025 Researchers found that people with anxiety disorders consistently show lower choline levels in key brain regions that regulate thinking and emotions. This biochemical difference may help explain why ...
Dec. 4, 2025 Researchers studying people with major psychiatric disorders found that drinking up to four cups of coffee a day is associated with longer telomeres. This suggests a potential slowing of biological ...
Dec. 3, 2025 A unique vaccine rollout in Wales gave researchers an accidental natural experiment that revealed a striking reduction in dementia among seniors who received the shingles vaccine. The protective ...
Dec. 2, 2025 Researchers have solved the decades-old mystery behind how a common pregnancy drug lowers blood pressure. It turns out the medication blocks a ...
Dec. 2, 2025 Scientists have discovered that a single gene, GRIN2A, can directly cause mental illness—something previously thought to stem only from many genes acting together. People with certain variants of ...
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