Inclusion Criteria:  Be over 18 years of age Present permanent chronic pain (for more than 3 months), secondary to a peripheral pathology (traumatic, orthopedic or neurological), located in the hand or forearm.  Exclusion Criteria:  Pregnant women People in emergency situations Persons unable to give informed consent Persons who are mentally or linguistically unable to understand the research test instructions Individuals who are not available to complete the entire study protocol Cognitive impairments that prevent the use of the equipment Psychiatric disorders Patients with seizure disorders Patients with central hemineglect Pain secondary to central nervous system pathology Patients with arrhythmia Patients with head tremors or head shaking.