Process-instructed Self Neuro-Modulation (PRISM) for Attention Deficit/ Hyperactivity Disorder - Adults

Inclusion Criteria: * Adults ages 18-60 years, inclusive at the time of consent * Able to provide signed informed consent * Any gender * Subjects with a current primary DSM-5 diagnosis of ADHD (including predominantly inattentive presentation, hyperactive presentation, or combined presentations) as confirmed by the ACDS Version 1.2. * Subjects who are not receiving any pharmacological treatment for ADHD must have an AISRS score of ≥ 28 at screening. Subjects who are receiving pharmacological treatment for ADHD at screening must have a minimum AISRS score of ≥ 22 at screening * Not requiring treatment for any comorbid psychiatric condition for at least 2 months * Normal or corrected-to-normal vision * Normal or corrected-to-normal hearing * No intention of changing medication or psychotherapy for the duration of the study at the time of recruitment Exclusion Criteria: * Concurrent substance abuse and/or history of substance use within 6 months * Use of any prescribed benzodiazepine * Lifetime bipolar disorder, psychotic disorder, autism, intellectual disability. Comorbid mood and anxiety disorders determined by the MINI will be permitted if they are not the primary focus of clinical attention * Active suicidality within past year, or history of suicide attempt in past 2 years * Any history of severe past drug dependence determined by the MINI (i.e., a focus of clinical attention or a cause of substantial social or occupational difficulty) * Any unstable medical or neurological condition * Any history of brain surgery, of penetrating, neurovascular, infectious, or other major brain injury, of epilepsy, or of other major neurological abnormality (including a history of traumatic brain injury \[TBI\] with loss of consciousness for more than 24 hours or posttraumatic amnesia for more than 7 days) * Any psychotropic medication * Recent initiation (within the past 3 months) of cognitive-behavioral therapy or any evidence-based PTSD psychotherapy (Cognitive Processing Therapy \[CPT\], Prolonged Exposure \[PE\], Eye Movement Desensitization and Reprocessing \[EMDR\]); continuation of established maintenance supportive therapy will be permitted * Significant hearing loss or severe sensory impairment * Enrollment in another research study testing an experimental, clinical, or behavioral intervention intended to affect symptoms initiated within the last 2 months, or intended enrollment within the next 2.5 months