Scientists have long noted that people suffering from Parkinsons disease commonly exhibit a specific personality type characterized by, among other things, a lower-than-average tendency to seek out new experiences. In explanation, investigators suggested that this trait was rooted in an inability to reap the pleasurable rewards of increased dopamine levels normally brought about by new stimuli because the disease destroys the neurotransmitter. Previous studies of personality and dopamine activity in Parkinsons patients involved subjects receiving treatment for their disease. Now, for the first time, scientists have examined the link between personality and Parkinsons in patients yet to receive medication. The report, published in the current issue of the Proceedings of the National Academy of Sciences indicates that, in fact, dopamine is not involved in regulating the low-novelty-seeking trait associated with Parkinsons.
Valtteri Kaasinen of the University of Turku in Finland and colleagues studied 61 patients who had been diagnosed with Parkinsons within the past five years but were not taking medication and compared them to a control group of 45 healthy subjects. Using personality questionnaires, the scientists compared traits such as novelty seeking and harm avoidance between the two groups. Unlike previously reported studies involving medicated patients, the correlation between low novelty seeking and Parkinsons was not highly significant. The authors suggest the previously demonstrated link may have been due in part to the medication administered to treat the disease. Parkinsons patients did, however, score significantly higher than control subjects for the harm avoidance personality trait, often associated with anxiety and depression. But the authors note that this trait is not disease-specific and "possibly reflects a psychological response to a chronic disease."
The team next investigated the explicit role of dopamine in mediating the personality of a Parkinsons patient. Using positron emission tomography (PET), the scientists studied the uptake of radioactively labeled L-DOPA (a precursor to dopamine) in the brains of 47 of the Parkinsons patients. Participants with high scores for harm avoidance demonstrated increased uptake of L-DOPA in the brains right caudate region. But patients with low scores for novelty seeking did not show a similar reaction to L-DOPA. "Although the results of this study are not in disagreement with the concept of low-novelty-seeking personality type in Parkinsons disease," the authors conclude, "the personality type does not seem to be dopamine dependent."
Sarah Graham | Scientific American
Researchers release the brakes on the immune system
18.10.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn
Norovirus evades immune system by hiding out in rare gut cells
12.10.2017 | University of Pennsylvania School of Medicine
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
18.10.2017 | Health and Medicine
18.10.2017 | Life Sciences
17.10.2017 | Life Sciences