Reference Terms
from Wikipedia, the free encyclopedia
Homosexuality
Homosexuality can refer to both attraction or sexual behavior between people of the same sex, or to a sexual orientation. When describing the latter, it refers to enduring sexual and romantic attraction towards those of the same sex, but not necessarily to sexual behavior. Homosexuality is contrasted with heterosexuality, bisexuality and asexuality.
Lesbian denotes a homosexual woman.
Most scientist today agree that sexual orientation is most likely the result of a complex interaction of environmental, cognitive and biological factors. Although homosexuality does not appear to be adaptive from an evolutionary standpoint, because homosexual sex does not produce children, there is evidence of its existence through human history.
Although a number of biological factors have been considered by scientists, such as prenatal hormones, chromosomes, polygenetic effects, brain structure and viral influences, no scientific consensus exists as to how biology influences sexual orientation.
Most scientists agree that it is unlikely that there is a single "gay gene" that determines something as complex as sexual orientation, and that it is more likely to be the result of an interaction of genetic, biological and environmental/cultural factors.
Related Stories
1
2
Mind & Brain News
October 29, 2026
Oct. 29, 2026 A surprising discovery at UC San Diego suggests that chronic lower back pain may become deeply embedded in the brain's sense of personal identity. Researchers found that movement-triggered pain activates a brain network associated with ...
Oct. 29, 2026 Scientists have identified a weakened brain signal that may connect several seemingly unrelated symptoms of schizophrenia, including sensory processing difficulties, disorganized speech, and greater symptom severity. The surprising discovery could ...
Oct. 29, 2026 A study of nearly 13,000 adults found that people consuming the most artificial sweeteners experienced a 62% faster decline in memory and thinking skills, equivalent to approximately 1.6 additional years of brain aging. Six popular sweeteners were ...
Oct. 29, 2026 Getting more daylight could be linked to a surprisingly powerful benefit for brain health. In a study of more than 87,000 adults, researchers found that higher daytime light exposure was associated with a 16% lower risk of dementia, with longer ...
Oct. 28, 2026 Researchers have discovered a small group of brain cells that prevents dangerous blood pressure swings, even when average readings appear normal. The finding reveals a hidden source of cardiovascular risk and could open the door to new treatments ...
Oct. 27, 2026 Why do some people stay mentally sharp even when their brains show signs of Alzheimer’s disease? Scientists in the Netherlands may have uncovered an important clue hidden in a rare group of ...
Oct. 26, 2026 Mayo Clinic scientists have uncovered surprising new insights into “zombie cells,” aging cells that linger in the body and contribute to inflammation and disease. Seven studies reveal why these ...
Oct. 25, 2026 A common, inexpensive medication could hold an unexpected clue to preventing dementia. Researchers found that older adults with a specific genetic profile had a 70% lower relative risk of dementia when taking low-dose aspirin, even though previous ...
Oct. 25, 2026 A cannabis-derived ingredient commonly found in sleep gummies may be more habit-forming than previously thought, with new research showing that repeated exposure caused tolerance and withdrawal symptoms in mice. Scientists warn that CBN may carry ...
Oct. 24, 2026 Scientists have uncovered a surprising new clue to why the Mediterranean diet is so good for the heart, brain, and healthy aging. Researchers at USC found that older adults who closely followed the diet had higher levels of two tiny proteins, ...
Oct. 23, 2026 Scientists discovered that the thick, sticky fluid surrounding glioblastoma tumors can make brain cancer cells smaller, more flexible, and better at invading surrounding tissue. Even more troubling, ...
Oct. 23, 2026 A newly FDA-cleared PTSD treatment uses personalized brain mapping and magnetic stimulation to target abnormal brain activity, with a clinical trial reporting a 52% reduction in symptoms and 68% remission. Researchers believe the technology could ...
Latest Headlines
updated 12:56 pm ET
Oct. 27, 2026 A major new study reveals that autistic children’s brains process faces differently, and those differences may begin earlier than scientists previously thought. Researchers found that brain signals ...
Oct. 25, 2026 For nearly a century, people in distant parts of the world have reported a bizarre experience after eating certain wild mushrooms: seeing dozens or even hundreds of tiny, colorful humans moving ...
Oct. 23, 2026 A seven-year study found that people with Parkinson’s disease who were more physically active experienced slower declines in memory, thinking, and ...
Oct. 23, 2026 A tiny region deep within the brain has surprised scientists by revealing a remarkably sophisticated communication system. Previously thought to broadcast the same chemical signal throughout the ...
Oct. 22, 2026 A surprising two-year clinical trial found that fish oil supplements successfully delivered omega-3s to the brain but failed to improve memory or protect against Alzheimer's-related brain shrinkage. ...
Oct. 22, 2026 Scientists have discovered why common marmosets have unusually small, smooth brains despite starting development much like other primates. The secret lies in subtle changes to brain-building cells ...
Oct. 20, 2026 The aging brain may be undergoing a remarkable transformation rather than simply losing its abilities, shifting its focus from remembering details to understanding the bigger picture. Scientists ...
Oct. 20, 2026 Scientists have found a promising way to protect the brain from Alzheimer’s-related damage by blocking immune cells that contribute to the ...
Oct. 19, 2026 Scientists have discovered why some people with a high genetic risk of Alzheimer’s remain mentally sharp into their 80s, uncovering a rare mutation that protects the brain from harmful protein ...
Oct. 19, 2026 Walking just 3,000 steps a day could help slow Alzheimer’s-related brain changes, according to new research. Scientists discovered that physical activity was linked to less buildup of harmful tau ...