Investigating the Effects of Repetitive Transcranial Magnetic Stimulation on Voice Function in Adults with Laryngeal Dystonia

What this Trial Is About

Laryngeal dystonia LD is a condition that causes excessive opening or closing of the vocal folds, leading to problems with voice quality, job prospects, self-worth, and overall quality of life. People with LD often experience symptoms like breathy voice, pitch breaks, and vocal tremor. While brain imaging has shown differences in brain areas related to voice control, the exact brain function behind LD is not fully understood. Current treatments like voice therapy and Botox injections provide temporary relief but have limitations. This research aims to study a non-invasive brain stimulation technique called repetitive transcranial magnetic stimulation rTMS to better understand and potentially improve brain control of voice muscles in LD. The study will compare 5 days of daily rTMS treatment targeting the left laryngeal motor cortex with a sham placebo rTMS treatment. Participants will receive about 20 minutes of rTMS each day using a specialized coil to stimulate brain areas responsible for voice muscle control. The sham treatment mimics the sensation and sound without actual brain stimulation. After the initial 5-day treatment and assessments, participants will cross over to receive the other treatment after at least 3 months. The study will measure voice changes and brain responses before and after each treatment phase. Participants will undergo detailed voice assessments, including listening tests, acoustic analysis, and self-reported voice effort ratings. Brain activity will be measured using a specialized neurophysiology assessment involving fine-wire electrodes inserted into voice muscles and brain stimulation tests to evaluate muscle control. Safety screenings will be done before treatments. Researchers will track changes in voice function and brain excitability at baseline, after treatment, and follow-up times. The total involvement includes initial screening, two treatment phases with assessments, and a follow-up period lasting several months.

Effects of Neuromodulation in Laryngeal Dystonia