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Opioid drug
An opioid is any agent that binds to opioid receptors, found principally in the central nervous system and gastrointestinal tract. There are four broad classes of opioids: endogenous opioid peptides, produced in the body; opium alkaloids, such as morphine (the prototypical opioid) and codeine; semi-synthetic opioids such as heroin and oxycodone; and fully synthetic opioids such as pethidine and methadone that have structures unrelated to the opium alkaloids. Opioids have long been used to treat acute pain (such as post-operative pain). They have also found to be invaluable in palliative care to alleviate the severe, chronic, disabling pain of terminal conditions such as cancer. Very high doses are often required in palliation to improve the patients' terminal quality-of-life.
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Mind & Brain News
January 29, 2026
Jan. 29, 2026 Scientists in Sweden and Norway have uncovered a promising way to spot Parkinson’s disease years—possibly decades—before its most damaging symptoms appear. By detecting subtle biological signals in the blood tied to how cells handle stress and ...
Jan. 28, 2026 A massive international study of more than 3,100 long COVID patients uncovered a striking divide in how brain-related symptoms are reported around the world. In the U.S., the vast majority of non-hospitalized patients described brain fog, ...
Jan. 28, 2026 Where your body stores fat may matter just as much as how much you carry—especially for your brain. Using advanced MRI scans and data from nearly 26,000 people, researchers identified two surprising fat patterns tied to faster brain aging, ...
Jan. 28, 2026 AI may learn better when it’s allowed to talk to itself. Researchers showed that internal “mumbling,” combined with short-term memory, helps AI adapt to new tasks, switch goals, and handle complex challenges more easily. This approach boosts ...
Jan. 27, 2026 A common parasite long thought to lie dormant is actually much more active and complex. Researchers found that Toxoplasma gondii cysts contain multiple parasite subtypes, not just one sleeping form. Some are primed to reactivate and cause disease, ...
Jan. 27, 2026 Findings could create new opportunities to treat and study neurodegenerative diseasesScientists discovered that sugar metabolism plays a surprising role in whether injured neurons collapse or cling to life. By activating internal protective ...
Jan. 27, 2026 Carbohydrates don’t just fuel the body—they may also influence how the brain ages. A large long-term study found that diets high in fast-acting carbs that rapidly raise blood sugar were linked to a higher risk of dementia. People who ate more ...
Jan. 26, 2026 A new genetic study suggests that obesity and high blood pressure may play a direct role in causing dementia, not just increasing the risk. By analyzing data from large populations in Denmark and the U.K., researchers found strong evidence that ...
Jan. 26, 2026 Alzheimer’s may destroy memory by flipping a single molecular switch that tells neurons to prune their own connections. Researchers found that both amyloid beta and inflammation converge on the same receptor, triggering synapse loss. Surprisingly, ...
Jan. 25, 2026 A massive new study comparing more than 100,000 people with today’s most advanced AI systems delivers a surprising result: generative AI can now beat the average human on certain creativity tests. Models like GPT-4 showed strong performance on ...
Jan. 25, 2026 Researchers have found that a natural aging-related molecule can repair key memory processes affected by Alzheimer’s disease. The compound improves communication between brain cells and restores early memory abilities that typically fade first. ...
Jan. 24, 2026 People with spinal cord injuries often lose movement even though their brains still send the right signals. Researchers tested whether EEG brain scans could capture those signals and reroute them to spinal stimulators. The system can detect when a ...
Latest Headlines
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Jan. 24, 2026 A large, decades-long study suggests that signs of ADHD in childhood may have consequences that extend well beyond school and behavior. Researchers followed nearly 11,000 people from childhood into ...
Jan. 23, 2026 Alzheimer’s may be driven far more by genetics than previously thought, with one gene playing an outsized role. Researchers found that up to nine in ten cases could be linked to the APOE gene — ...
Jan. 23, 2026 New research suggests that auditory hallucinations in schizophrenia may come from a brain glitch that confuses inner thoughts for external voices. Normally, the brain predicts the sound of its own ...
Jan. 22, 2026 A new study reveals that super agers over 80 have a distinct genetic edge. They are much less likely to carry the gene most associated with Alzheimer’s risk, even when compared with other healthy ...
Jan. 22, 2026 New research suggests that consistent aerobic exercise can help keep your brain biologically younger. Adults who exercised regularly for a year showed brains that appeared nearly a year younger than ...
Jan. 21, 2026 Scientists have discovered that the human brain understands spoken language in a way that closely resembles how advanced AI language models work. By tracking brain activity as people listened to a ...
Jan. 20, 2026 Researchers report that vagus nerve stimulation helped many people with long-standing, treatment-resistant depression feel better—and stay ...
Jan. 20, 2026 Researchers have identified a key molecular interaction that accelerates Parkinson’s disease by damaging the brain’s energy systems. They ...
Jan. 20, 2026 When you’re short on sleep and your focus suddenly drifts, your brain may be briefly slipping into cleanup mode. Scientists discovered that these attention lapses coincide with waves of fluid ...
Jan. 19, 2026 Scientists at Johns Hopkins have uncovered a surprising new way to influence brain activity by targeting a long-mysterious class of proteins linked to anxiety, schizophrenia, and movement disorders. ...