Parkinson's alters emotion-related bodily sensations

Researchers at the University of Turku and Turku University Hospital have shown that bodily sensations related to emotions are altered by the neurological movement disorder known as Parkinson’s disease. Their findings have been published in the journal Movement Disorders.

Emotions regulate our hormones and many of the body’s vital functions, and can also be associated with strong physical reactions and sensations — such as an increase in heart rate and blood pressure when we’re frightened or butterflies in the stomach when going on a first date. Parkinson’s disease, meanwhile, is characterised by motor symptoms (such as slowness, stiffness and tremor) but is also associated with a number of non-motor symptoms — including dysfunction of the autonomic nervous system, which has an influence on blood circulation and gastrointestinal tract function.

Doctoral researcher Kalle Niemi and his colleagues investigated the bodily sensations of basic emotions (anger, disgust, fear, happiness, sadness, surprise and neutral) in Finnish Parkinson’s disease patients. The subjects were asked to identify their symptoms and bodily sensations associated with different emotions by drawing them on an electronic human body map using a computer mouse.

People with Parkinson’s disease were found to have significant differences in all bodily sensations related to basic emotions when compared with the control subjects. The differences were most pronounced in the bodily sensations of anger, which in healthy people are focused in the chest area. In people with Parkinson’s disease, the bodily sensation of anger in the chest was reduced and seemed to shift more to the abdominal region as the disease progressed, consistent with the dysfunction of the autonomic nervous system associated with Parkinson’s disease.

The descriptions of the Parkinson’s disease patients on their emotion-related bodily sensations differed from those of the control subjects. Image credit: Clinical Neurosciences, University of Turku.

“In recent years, there has been a growing realisation that the non-motor symptoms of Parkinson’s disease have a significant impact on the patients’ quality of life,” Niemi said. “The results of our study highlight yet another non-motor phenomenon.”

Emotional abnormalities are common in psychiatric disorders — with negative emotions often increasing disease symptoms — but this is the first known study to show abnormalities in the emotion-related bodily sensations in a neurological disorder. The results may open up new perspectives into the symptoms and possibly even treatment of symptoms in neurological disorders.

“The results of our study raise many interesting questions about the role of emotions in the symptoms of Parkinson's disease,” said Professor Juho Joutsa, principal investigator of the study. “Extending our research method to other diseases offers new possibilities for neurology research.”

Top image credit: iStock.com/Alexey Koza