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Reference Terms
from Wikipedia, the free encyclopedia

Laughter

Laughter is the biological reaction of humans to moments or occasions of humor: an outward expression of amusement. Laughter is subcategorised into various groupings depending upon the extent and pitch of the laughter: giggles, clicks (which can be almost silent), chortles, chuckles, hoots, cackles, sniggers and guffaws are all types of laughter. Smiling may be considered a mild silent form of laughter. Some studies indicate that laughter differs depending upon the gender of the laughing person: women tend to laugh in a more "sing-song" way, while men more often grunt or snort.

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Mind & Brain News

February 27, 2026

Worrying about getting older—especially fearing future health problems—may actually speed up aging at the cellular level, according to new research from NYU. In a study of more than 700 women, those who felt more anxious about aging showed signs ...
Scientists have zeroed in on a critical weak spot behind a rare but devastating brain autoimmune disorder often known as “Brain on Fire.” The disease strikes when the immune system attacks NMDA receptors—key molecules involved in memory and ...
A weeklong, high-intensity version of TMS may work nearly as well as the standard six-week treatment for depression. In a UCLA study, patients who received five sessions a day for five days experienced meaningful symptom relief comparable to those ...
Subtle changes in brain blood flow and oxygen use are closely linked to hallmark signs of Alzheimer’s, including amyloid plaques and memory-related brain shrinkage. Simple, noninvasive scans may one day help spot risk earlier—by looking at the ...
Scientists have created a blood test that can estimate when Alzheimer’s symptoms are likely to begin. By measuring a protein called p-tau217, the model predicts symptom onset within roughly three to four years. The protein mirrors the silent ...
A common bacterium best known for causing pneumonia and sinus infections may also play a surprising role in Alzheimer’s disease. Researchers found that Chlamydia pneumoniae can invade the retina and brain, where it sparks inflammation, nerve cell ...
Exercise may sharpen the mind by repairing the brain’s protective shield. Researchers found that physical activity prompts the liver to release an enzyme that removes a harmful protein causing the blood-brain barrier to become leaky with age. In ...
A groundbreaking clinical trial is testing whether specially engineered stem cells can help the brain restore its own dopamine production in people with Parkinson’s disease. Because the condition is driven by the gradual loss of dopamine-producing ...
Breathing polluted air may do more than harm your lungs — it could also increase your risk of Alzheimer’s disease. In a sweeping study of nearly 28 million older Americans, researchers found that ...
Sugary drinks may be linked to more than just physical health problems in teens. A new review of multiple studies found a consistent association between high consumption of beverages like soda, energy drinks, sweetened juices, and flavored milks and ...
A major new study has spotlighted three familiar medicines that could take on an unexpected new role in the fight against Alzheimer’s disease — with a shingles vaccine emerging as the front-runner. After reviewing 80 existing drugs, an ...
Researchers have identified two brain receptors that help the brain clear away amyloid beta, a hallmark of Alzheimer’s disease. By stimulating these receptors in mice, scientists increased levels of a natural amyloid-breaking enzyme, reduced ...

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