New! Sign up for our free email newsletter.
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
 


Mind & Brain News

August 7, 2026

Blocking the glycine transporter SLC6A20 restored important brain signaling and improved social, communication, and repetitive behaviors in autism-related mouse models. The treatment also worked in human brain organoids and showed lasting effects in ...
A ten-month Antarctic experiment found that astronauts may struggle not only with loneliness but also with spending too much time around the same people. Frequent contact was linked to greater ...
A new wearable patch may help people reach REM sleep faster and remain there longer without medication or surgery. In a study of 28 participants, the device shortened the time to REM by 43 minutes and extended it by about 16 minutes. Researchers ...
Beginning around age 50, the brain’s memory center appears to lose many of its longtime immune cells and replace them with more inflammatory ones. This surprising shift may help explain how normal aging sets the stage for Alzheimer’s disease and ...
A long-term brain study found that common risks such as smoking, high blood pressure, heart disease, and high blood lipids were strongly linked to damage associated with vascular dementia. The findings suggest that healthier lifestyle choices could ...
A prescription form of THC helped many people with PTSD escape recurring trauma-related nightmares, with more than one-third reporting that the nightmares disappeared completely after ten weeks. The ...
A simple change in posture may subtly affect how people feel and make decisions. Participants who sat upright reported greater feelings of pride and took more successful risks in a virtual balloon game than those who hunched over. Most did not ...
Weight loss is not simply a test of willpower. The human brain evolved to protect body fat during times of scarcity, and it can treat a previously higher weight as the new normal, triggering stronger hunger, cravings, and lower energy use after ...
Scientists have identified a molecular switch that may help explain why aging makes the brain more vulnerable to diseases such as ALS and Huntington’s. In worms, the protein EPS8 builds up with age and triggers signaling that encourages toxic ...
Vanderbilt researchers created the first selective compound designed to inhibit TAOK-1, a poorly understood protein connected to Alzheimer’s disease. They also discovered a second compound that activates the entire TAOK protein family, offering ...
A new report suggests that blood pressure may be controlled more effectively by increasing potassium while also cutting sodium. Potassium-rich foods can help balance sodium’s effects, but most people consume far less potassium than ...
A gene involved in the brain’s overnight cleaning system may change how strongly poor sleep affects Alzheimer’s-related brain changes. The findings point toward more personalized prevention strategies based on both genetics and sleep ...

Latest Headlines

updated 12:56 pm ET