ECoG Signals for Motor and Speech Control in Neurological Disorders

Inclusion Criteria: 1. Age \> 21 2. Limited ability to use upper limbs, based on neurological examination, due to stroke, amyotrophic lateral sclerosis (ALS), multiple sclerosis, cervical spinal cord injury, brainstem stroke, muscular dystrophy, myopathy or severe neuropathy. 3. Disability, defined by a 4 or greater score on the Modified Rankin Scale, must be severe enough to cause loss of independence and inability to perform activities of daily living. 4. If stroke or spinal cord injury, at least 1 year has passed since onset of symptoms 5. Must live within a two-hour drive of UCSF Exclusion Criteria: 1. Pregnancy or breastfeeding 2. Inability to understand and/or read English 3. Inability to give consent 4. Dementia, based on history, physical exam, and MMSE 5. Active depression (BDI \> 20) or other psychiatric illness (active general anxiety disorder, schizophrenia, bipolar disorder, obsessive-compulsive disorder (OCD), or personality disorders (e.g. multiple personality disorder, borderline personality disorder, etc.) 6. History of suicide attempt or suicidal ideation 7. History of substance abuse 8. Co-morbidities including ongoing anticoagulation, uncontrolled hypertension, cancer, or major organ system failure 9. Inability to comply with study follow-up visits 10. Any prior intracranial surgery 11. History of seizures 12. Immunocompromised 13. Has an active infection 14. Has a CSF drainage system or an active CSF leak 15. Requires diathermy, electroconvulsive therapy (ECT), or transcranial magnetic stimulation (TMS) to treat a chronic condition 16. Has an implanted electronic device such as a neurostimulator, cardiac pacemaker/defibrillator or medication pump, or presence of any head or neck metallic foreign bodies 17. Allergies or known hypersensitivity to materials in the Blackrock NeuroPort Array (i.e. silicone, titanium) or the PMT Subdural Cortical Electrode (silicone, platinum iridium, nichrome)