More Drinking, More Dopamine?
Results from a study published in the Proceedings of the National Academy of Science suggest that a gene involved in dopamine release may be associated with binge drinking in teens. RASGRF-2 knockout mice did not release dopamine from neurons in the ventral tegmental area (VTA) area of the brain. Dopamine is a neurotransmitter brain cells release when we do something that feels good, also known as the “reward” system. A study in teenage boys found a RASGRF-2 variant tied to more brain activity associated with the VTA and dopamine release, and at 16, those with the variant drank alcohol more often. Alcohol abuse kills 2.5 million people around the world annually and is predicted to lead to the early deaths of 210,000 people over the next twenty years in England and Wales.
If Partner Dozes off, No Problem
Roughly 40 percent of our daily speech is devoted to one primary subject: ourselves. Neuroscientists at Harvard wondered if there was more than mere vanity or self-absorption behind this phenomenon, and conducted a series of tests which indicated that we talk about our own thoughts, feelings and accomplishments because it turns us on. More accurately, MRI scans have revealed that talking about ourselves triggers heightened activity in our brain's mesolimbic dopamine system, the area of the brain that produces the rewarding feeling of satisfaction associated with sex, food, and money. It may be even stronger than money: when offered small cash amounts to discuss other people, volunteers turned down up to 25 percent of the possible income to reveal information about themselves instead.
Pursued by Parkinson's
People with REM sleep behavior disorder may be more at risk for developing Parkinson's disease, say researchers. For the third time in five years, Lancet Neurology has published work on the link between Parkinson's disease and REM disorder. Individuals with the REM disorder have nightmares in which they're being pursued or attacked, but they also act out those dreams with cries, punches, screams or kicks. In the new study, researchers used brain SPECT to discover that levels of dopamine in the brain decrease more quickly in patients with REM disorder. The three-year study compared the evolution of brain SPECT in 20 patients with the REM disorder and 20 controls. Patients with the REM disorder experienced a 20 percent drop in dopamine compared with an 8 percent drop in the controls.
Biological Reason for Anorexia
While most people finding dieting and losing weight difficult, people with anorexia nervosa can starve themselves, even to death. Researchers cite dopamine, a brain chemical that is released by eating as the cause. In healthy people, dopamine triggers feelings of extreme pleasure in the reward center of the brain. In those with anorexia, dopamine activates the part of the brain that makes people anxious. "This is the first study to demonstrate a biological reason why individuals with anorexia nervosa have a paradoxical response to food," said lead researcher Walter Kaye, MD, UC San Diego. It’s important to note that the study was of people who’d recovered from anorexia for at least a year indicating that anorexia may be due to pre-existing traits, say researchers.
Hope Is a Reward in Parkinson's
Brain scans of people with Parkinson’s disease who were told they had a 75 percent chance of receiving levodopa showed dopamine was released even though they only received a placebo. Some of the 35 individuals were also told they had a 25, 50 and 100 percent chance of receiving the drug but only received the placebo as well, but the response was only seen in the 75 percent chance group. Sarah C. Lidstone, of the Pacific Parkinson's Research Centre at Vancouver Coastal Health and the University of British Columbia, Vancouver, and colleagues wrote that "This is in keeping with studies on conditioned learning in which dopaminergic activation is seen when reward is deemed likely but not certain." The study can be found in the August issue of the journal Archives of General Psychiatry.
Not Only Due to Estrogen Loss
Up to 70 percent of new mothers experience symptoms of depression within the first week after giving birth. While, the symptoms dissipate in most cases, up to 13 percent of women experience clinical level postpartum depression (PPD). Fluctuations in estrogen have been to blame but now new research reveals that, while estrogen levels drop 100 to 1000 fold after giving birth, levels of the enzyme monoamine oxidase A (MAO-A) increase dramatically throughout the brain. MAO-A is responsible for breaking down neurotransmitters serotonin, dopamine, and norepinephrine, and, ultimately, for controlling our moods. By balancing MAO-A, this research “could have an impact on prevention and treatment of postpartum depression in the future", says lead author Julia Sacher.
Could Explain Vincent Van Gogh
Creativity has been found to be linked to a slightly higher incidence of bipolar disorder and schizophrenia say researchers at the Karolinska Institutet, Sweden, who also found that the extremely creative have a higher incidence of mental illness in their families. Researchers point to the brain’s dopamine system, the receptor genes of which are linked to a person’s ability to find different solutions to a problem. Psychological testing shows that highly creative problem solvers had similar dopamine brain chemistries as schizophrenics. "Fewer D2 receptors in the [brain] probably means a lower degree of signal filtering, and thus a higher flow of information, says researcher Dr. Fredrik Ullén, who adds, “Thinking outside the box might be facilitated by having a somewhat less intact box."