Type 2 Diabetes and Blood Brain Barrier Improvement

Inclusion Criteria: * Diagnosed T2DM * Outpatient status * Able to lay flat for imaging Exclusion Criteria: * A previous history of stroke * Current in-take of thiamine * Known thiamine allergy * Seizure disorder * Head trauma * Myocardial infarction * Current pregnancy (if female) * Diagnosed neuropsychiatric disorders (clinical depression, schizophrenia, manic-depression) * Diagnosed dementia * Sleep disordered breathing * Airway or chest deformities that would interfere with breathing * Chronic obstructive pulmonary disease * Cystic fibrosis * Presence of brain mass lesions * Any history of drug abuse (e.g., cocaine, tobacco, or cannabis) * Renal failure (requiring dialysis) * All T2DM adults with metallic and electronic implants (phrenic or cardiac pacemakers; although some pacemakers and cardioverter defibrillators are safe at a low magnetic field, they are not safe at 3.0-Tesla scanner) * Non-removable insulin pump/glucose sensor * Braces * Body weight more than 300 pounds (weight and height will be used to calculate BMI to determine if the patient will fit in the scanner and stay within parameters of size restrictions of MRI scanner table) * Any other contraindications to MRI, such as claustrophobia, or metallic-based tattoos, as per MRI safety website suggestions, will also be excluded.