A recent study has discovered a connection between the neurotransmitter dopamine and the mentalizing abilities of healthy individuals. This is the first time that such a link has been established. Mentalizing refers to the ability to attribute and comprehend mental states, such as thoughts, feelings, and intentions, in oneself and others. Scientists at the University of Birmingham have found that altering dopamine levels in the brain can impact a person’s mentalizing skills. Their findings have been published.A new study published in PLOS Biology today explores the role of dopamine in the brain. Dopamine is a neurotransmitter, which is a chemical messenger in the brain that is known for its involvement in pleasure, motivation, and learning. It is also understood that low levels of dopamine in the brain areas that control movement are responsible for the main symptoms of conditions like Parkinson’s disease.
Additionally, Parkinson’s disease is also associated with socio-cognitive problems, such as difficulties with recognizing emotions or mentalizing. However, there has not been a definitive link established between these problems and imbalances in dopamine. More commonly, theory of mind issues are often associated with Parkinson’s disease.Psychosocial changes such as isolation and social withdrawal have been linked to difficulties that are commonly seen in dopamine-related disorders.
Dr Bianca Schuster, the lead author from the University of Birmingham’s School of Psychology, explained that while the mental abilities of individuals with Parkinson’s may not be the main focus of treatment, it still greatly impacts those with the disease. Understanding how dopamine imbalances can affect mental processes in the brain could be very important for individuals with the disease.Secondary effects of the medications prescribed for Parkinson’s and other disorders were the focus of the study. It involved 33 healthy volunteers who participated in a double-blind, placebo-controlled experiment. The participants were given haloperidol, a drug that blocks dopamine receptors in the brain, on one day and a placebo on another day. They completed an animations task, where they interpreted videos of interacting triangles.The researchers conducted a study where participants watched videos and selected the label that best described the ongoing scene. Another part of the study involved participants judging emotions portrayed by whole-body point light displays (videos of actors with only visible joint movements; published here: Schuster et al., 2021, Journal of Neuroscience).
The researchers discovered that participants who took haloperidol were noticeably less accurate in attributing mental states to the interactions depicted in the animations. This was linked to the drug’s impact on emotion recognition.
Dr. Schuster noted that in disorders involving dopamine dysfunctions, the imbalance of dopamine not only causes the main symptoms of the disorder (such as motor symptoms in Parkinson’s disease), but also impacts the socio-cognitive abilities of individuals. He also mentioned that this research could potentially influence the treatment of Parkinson’s disease in the future, as well as the use of drugs that affect dopamine action in the brain.
