Could gentle electrical pulses steady shaky hands?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria for Healthy Participants: * Age from 18 to 80 years, inclusive * No history of a brain and/or skull lesion * Normal hearing and (corrected) vision * Able to understand and give informed consent * No neurological disorders * No tremor * Able to understand and speak English Exclusion Criteria for Healthy Participants: * History of significant head trauma (i.e., extended loss of consciousness, neurological damage) * Known structural brain lesion * Prior neurosurgical procedures * Tremors (as determined by study team) * Co-existence of other neurological diseases * Parkinsonism * Medical (e.g., cardiological, renal, hepatic, oncological) or psychiatric disease that would interfere with study procedures * Pathology that could cause abnormal movements of extremities (e.g., epilepsy, stroke, marked arthritis, etc.) * Inability to perform study tasks or assessments (e.g., follow instructions to stay still during asES procedures) or unable/unwilling to complete study forms * Non-prescribed drug use or recreational marijuana use * History of current substance abuse (exception: current nicotine use is allowed) * Pregnancy * Prisoners Inclusion Criteria for ET Patients: * Age from 18 to 80 years, inclusive * No prior history of skull lesions or craniotomy * Normal hearing and (corrected) vision * Able to understand and give informed consent * Diagnosis of ET (Tremor Research investigation Group criteria) by a physician * At least moderate-severe tremor (based on the TETRAS Tremor Rating Scale) in an upper limb with pure flexion-extension wrist tremor during posture * Stable medication doses for at least 30 days prior to study enrollment and during entire study period * Able to understand and speak English Exclusion Criteria for ET Patients: * History of significant head trauma (i.e., extended loss of consciousness, neurological damage) * Known structural brain lesion * Prior neurosurgical procedures * Mixed or complex tremors (as determined by study team) * Co-existence of other neurological diseases * Parkinsonism * Medical (e.g., cardiological, renal, hepatic, oncological) or psychiatric disease that would - interfere with study procedures * Pathology that could cause abnormal movements of extremities (e.g., epilepsy, stroke, marked arthritis, etc.) * Inability to perform the study tasks or assessments (e.g., follow instructions to stay still during asES procedures) or unable/unwilling to complete study forms * Non-prescribed drug use or recreational marijuana use * History of current substance abuse (exception: current nicotine use is allowed) * Pregnancy * Prisoners