dopamine tagged posts

Marijuana plant (stock image). Evidence of a compromised dopamine system has been found in heavy users of marijuana. Credit: © Vasily Merkushev / Fotolia

Evidence of a compromised dopamine system has been found in heavy users of marijuana. Effect similar to other addictions. Lower dopamine release was found in the striatum – involved in working memory, impulsive behavior, and attention. Previous studies have shown that addiction to other drugs of abuse, such as cocaine and heroin, have similar effects on dopamine release, but such evidence for cannabis was missing until now.

“In light of the more widespread acceptance and use of marijuana, especially by young people, we believe it is important to look more closely at the potentially addictive effects of cannabis on key regions of the brai...

Dopamine innervation into the hippocampus. Green denotes general catecholamine — a general name for dopamine — innervation of the CA1 region of the hippocampus. Yellows denotes dopamine nerve endings in the same region. Scale bar is 50 microns. Credit: John Dani, Ph.D., Perelman School of Medicine, University of Pennsylvania

Dopamine regulates how mice learn to avoid a disagreeable encounter, according to new research from the Perelman School of Medicine at the University of Pennsylvania. “We know that dopamine reinforces ‘rewarding’ behaviors, but to our surprise, we have now shown that situations that animals learn to avoid are also regulated by dopamine,” said John Dani, PhD, chair of the department of Neuroscience.

Special neurons in the brain send out a burst of dopamine in both negat...

Image of a rodent brain cell, with insulin receptors (seen as many green dots) that when activated spur release of dopamine (In background in pink is neuron nucleus.) Credit: Courtesy of Nature Communications

Insulin, essential for controlling blood sugar levels and feeling of being full after eating, plays a much stronger role than previously known in regulating release of dopamine, a neurotransmitter that helps control the brain’s reward and pleasure centers, new studies by researchers at NYU Langone Medical Center show.

“We found that when there’s more insulin in the brain, there will be more dopamine released, not less,” says study senior investigator and NYU Langone neuroscientist Margaret Rice, PhD...

Dopamine-dependent long term depression of mediated transmission profoundly disrupts normal synaptic transmission between hippocampus and PFC. These results show how dopaminergic activation induces long-term hypofunction of NMDARs, which can contribute to disordered functional connectivity, a characteristic that is a hallmark of psychiatric disorders such as schizophrenia. Credit: https://neurowiki2012.wikispaces.com/file/view/Reward_circuit.jpg/315908202/Reward_circuit.jpg

New research reveals mechanisms that trigger disruption in the brain’s communication channels linked to symptoms in psychiatric disorders. This research could have important implications for treating symptoms of brain disorders.

Many of our everyday cognitive functions such as learning and memory rely on normal communic...