Using neurofeedback from motor cortex to reduce tremor in essential tremor

Abstract

Elusive to a cause, Essential Tremor (ET) has been classified as the most common adult movement disorder. Current research suggests that ET may be centrally driven and stem from an oscillating neural network involving motor cortex and subcortical regions. ET is typically treated through costly, invasive methods to disrupt this oscillating network by targeting subcortical regions within the brain. Another, non-invasive, method which may disrupt this same network is neurofeedback (NF). Using real-time representation of activity in the brain, NF is a technique which encourages the user to self-manipulate their own brain activity. However, many people have difficulty controlling the NF signal. Current research lacks a determinant of who can and cannot use NF successfully. To that end, the purpose of this study is to determine whether individuals diagnosed with ET are capable of manipulating power of the theta and beta (4:8hz, and 12-15hz) frequency bands using NF. Participants were given audio feedback, through headphones, to train them to enhance and suppress a theta/beta ratio, in separate sessions, using EEG recorded over motor cortex. During each session participants underwent, eight, three-minute blocks of NF. Tremor was recorded pre and post training using accelerometers. Similar to previous work using other patient populations and healthy controls, there were individual differences in the ET patients who were able to control the NF signal. Exploring these individual differences provides a basis of knowledge for future NF studies to explore the impact of using longer training protocols to reduce tremor in patients with ET.

Acknowledgments: Nova Scotia Health Research Foundation