The REMIND Study- SPARK Neuro Software Study

Inclusion Criteria: 1. Age 55 to 85 at the time of consent 2. Informant available and willing (remotely or in-person) to provide information about sleep patterns and cognitive functioning who spends \>8 hours per week with primary subject 3. Subject or Legally Authorized Representative (LAR) has the ability to provide informed consent and comply with the protocol. Exclusion Criteria: 1. Unable to remain still for up to 30 minutes during EEG data recording 2. Subjects currently on and unable to wash out concomitant medications, including: 1) opiates; 2) benzodiazepines and nonbenzodiazepine hypnotics; 3) sedative antihistamines; 4) tricyclic anti-depressants; 5) skeletal muscle relaxants; 6) antiepileptics; 7) antipsychotics; 8) antimanic agents; 9) THC; 10) anticholinergics 3. Previous history of craniotomy 4. Medical or psychiatric illness that would interfere with study participation 5. History of epilepsy or chronic seizure disorder 6. Presence of non-dental metal in head 7. Currently experiencing a skin disease on scalp that would affect electrode contacts 8. Subject meets at least one of the following criteria: 1. Diagnosis of cognitive impairment from various underlying pathologies as indicated by one of the diagnostic codes listed in Appendix A (protocol) 2. MMSE score of 27 or less 3. Treating physician or PI have documented that the patient is cognitively impaired, with judgment of cognitive impairment having been made within the 6 months prior to enrollment 9. Substance Use Disorder, including Alcohol