Reference Terms
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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
October 26, 2025
Oct. 26, 2025 — GLP-1 drugs, originally developed for diabetes and obesity, may also curb addictive behaviors by acting on reward circuits in the brain. Early trials show reductions in alcohol intake, opioid seeking, and nicotine use. Though more research is ...
Oct. 25, 2025 — A new study shows that eating more fruits and vegetables during the day can significantly improve sleep that same night. Researchers found a clear link between diet quality and sleep depth, with participants who met the CDC’s daily produce ...
Oct. 25, 2025 — Researchers found that neurons can use fat, not just sugar, to power the brain. When a protein called DDHD2 fails, this process breaks down and leads to serious brain problems. Scientists were able to restore damaged cells by feeding them fatty ...
Oct. 25, 2025 — Inside your body, an intricate communication network constantly monitors breathing, heart rate, digestion, and immune function — a hidden “sixth sense” called interoception. Now, Nobel laureate ...
Oct. 24, 2025 — A massive genetic study found that naturally lower cholesterol is linked to a dramatically reduced risk of dementia. The research simulated the effects of cholesterol-lowering drugs and showed up to an 80% lower risk for certain genetic profiles. ...
Oct. 24, 2025 — Researchers have finally seen and measured the tiny alpha-synuclein oligomers that may ignite Parkinson’s disease. With the ultra-sensitive ASA-PD imaging method, they captured these clusters in brain tissue, finding larger and more numerous ...
Oct. 23, 2025 — Cedars-Sinai researchers created “young” immune cells from human stem cells that reversed cognitive decline and Alzheimer’s symptoms in mice. The treated animals showed better memory and healthier brain structures. The cells seemed to protect ...
Oct. 22, 2025 — Scientists have uncovered a toxic alliance between Aβ and fibrinogen that may explain how Alzheimer’s disease begins. The two proteins together create stubborn clots that damage blood vessels and spark inflammation in the brain. These effects ...
Oct. 21, 2025 — New research reveals that exercise counteracts the mood-damaging effects of a Western-style diet through specific gut and hormonal mechanisms. Running restored metabolites tied to mental well-being and balanced key hormones like insulin and leptin. ...
Oct. 21, 2025 — Mizzou scientists are exploring how a ketogenic diet may protect the brain and prevent Alzheimer’s in people genetically predisposed to it. Their study found that female mice with the APOE4 gene benefited most, showing improved gut and brain ...
Oct. 21, 2025 — Menopause brings profound shifts not just in hormones but in the very structure of the brain. Scientists have found that gray matter in regions tied to memory and thinking can shrink, while white matter may show damage linked to blood flow issues. ...
Oct. 21, 2025 — Scientists at UCSF have uncovered evidence that multiple sclerosis silently damages the brain years before diagnosis. By studying proteins in blood samples, they identified early immune signals and markers of nerve damage. The findings point to IL-3 ...
Latest Headlines
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Oct. 20, 2025 — Feeling in control may be the key to conquering daily stress. Penn State researchers found that people were 62% more likely to resolve everyday hassles on days when they felt greater control. This ...
Oct. 20, 2025 — A massive brain imaging study of nearly 30,000 people has uncovered striking connections between eating ultra-processed foods and measurable changes in brain structure. These changes may be tied to ...
Oct. 20, 2025 — A major collaboration between UC San Diego and 23andMe identified genes that shape cannabis use behaviors. The study linked the CADM2 and GRM3 genes to cannabis use and connected these patterns to ...
Oct. 19, 2025 — SuperAgers defy normal aging by keeping sharp memories and healthy brains well into their 80s. Northwestern scientists discovered that these ...
Oct. 18, 2025 — Stanford scientists have solved a long-standing challenge in growing brain organoids by using a simple food additive to keep them from sticking ...
Oct. 18, 2025 — A long-term Australian study found that calcium supplements do not raise dementia risk in older women, countering previous fears. The research followed more than 1,400 participants for nearly 15 ...
Oct. 16, 2025 — Long before humans built cities or wrote words, our ancestors may have faced a hidden threat that shaped who we became. Scientists studying ancient teeth found that early humans, great apes, and even ...
Oct. 16, 2025 — Johns Hopkins scientists uncovered microscopic “nanotube” channels that neurons use to transfer toxic molecules. While this process clears waste, it can also spread harmful proteins like ...
Oct. 14, 2025 — Researchers have synthesized enhanced vitamin K analogues that outperform natural vitamin K in promoting neuron growth. The new compounds, which combine vitamin K with retinoic acid, activate the ...
Oct. 14, 2025 — Researchers at USC have created the first method to noninvasively measure microscopic blood vessel pulses in the human brain. Using advanced 7T MRI, they found these tiny pulsations grow stronger ...