Science: great progress! It is revealed that the primary tremor is caused by the hyperactive brain waves at the bottom of the brain

January 18, 2020 / BIOON / - -- essential tremor, also known as idiopathic tremor, is a kind of movement disorder that causes the involuntary tremor of hands, arms and head Its origin has always been a mystery, blocking the development of effective therapies for 4% of people over 40 with the disease Now, in a new study, researchers from Taiwan University, Columbia University, Yale University and other research institutions point out that primary tremor is caused by over active brain waves at the bottom of the brain, which increases the possibility of using neural regulation to treat this kind of motor disorder The related research results were published in the Journal of Science Translational Medicine on January 15, 2020 The title of the paper is "cerebellar constructions driven by synthetic pruning defects of cerebellar clipping fibers contribution to tremor pathway" Picture from Science Translational Medicine, 2020, DOI: 10.1126/scitranslmed.aay1769 "Past studies have identified structural changes in the brain in patients with primary tremor, but we don't know how these changes lead to tremor," said Dr Sheng Han Kuo, associate professor of Neurology at the waglos School of internal and external Sciences at Columbia University This new study determines how these structural changes affect brain activity, which can cause tremors " About primary tremor primary tremor is the most common motor disorder in the United States, affecting about 10 million Americans (about eight times as many as Parkinson's patients) The disease usually causes unconscious, rhythmic tremors, which usually occur on the hands, especially when buttoning shirts or using utensils Although primary tremor is not life-threatening, it can seriously affect the quality of life Some beta blockers and antiepileptics can reduce symptoms, but they have side effects such as fatigue and shortness of breath They also do not work well in patients with primary tremor Kuo said this was not surprising because the cause of the disease has not been well understood Patients with primary tremor have excessive brain activity in the cerebellum Researchers have previously identified changes in the structure of the cerebellum in patients with primary tremor and used a new electroencephalogram (EEG) technology to search for abnormal brain waves in this part of the brain Most of the 20 patients with primary tremor who were examined by cerebellar electrogram had strong cerebellar vibrations (between 4 and 12 Hz), which were not found in 20 control subjects Patients with more severe primary tremor had stronger tremors Brain tremors were first found in mice The researchers first found cerebellar tremors in mice, which produce tremors very similar to those observed in patients with primary tremor Stimulation of some neurons in the mouse brain, alternately inhibiting and releasing brain vibration, can lead to tremor "These results establish a causal relationship between brain vibration and tremor, which cannot be tested directly in patients," Kuo said Excessive vibration is caused by too many synapses In previous studies on the dead brain tissues of patients with primary tremor, Kuo's team has found that there are abnormally large synapses between two types of neurons in the cerebellum of patients with primary tremor: the climbing fiber and the Purkinje cell In this new study, using postmortem brain tissue again, the researchers found that the formation of these synapses (i.e., neural connections) appears to be influenced by a protein called glutamate receptor δ 2 (GluR δ 2) "When this protein is underexpressed, any excess synapses formed between reptile fibers and Purkinje cells are not eliminated, resulting in excessive neural connections," Kuo said When the Kuo team reduced the expression of GluR δ 2 in mice, they experienced tremors similar to those in humans Restoration of GluR δ 2 function can inhibit tremor, thus confirming that the protein plays a key role in primary tremor Kuo said the new study opens up a variety of new possibilities for the treatment of primary tremor "Guided by cerebellar EEG, we may be able to use neuromodulation techniques, such as tDCS (transcranial direct current stimulation) or TMS, to reduce tremor, or even drugs to reduce the transmission between reptile fibers and Purkinje cells," Kuo said Kuo is also working on drugs that increase the expression of GluR δ 2 in the brain, which may reduce tremor (BIOON Com) reference: 1 Ming Kai pan et al Cerebellar constructions driven by synthetic pruning modifications of cerebellar clipping fibers contribution to tremor pathway Science Translational Medicine, 2020, doi:10.1126/scitranslmed.aay1769 2.Cerebellar oscillations driven by synaptic pruning deficits of cerebellar climbing fibers contribute to tremor pathophysiology https://medicalxpress.com/news/2020-01-overactive-brain-trigger-essential-tremor.html