The investigators hypothesized that during the 9-week course of Engage & Connect treatment there will be an increase in brain functions of the Positive Valence System which in turn will lead to reduction in suicidality.

Social disconnection peaks in middle and late life and leads to an increased risk of suicide, persistent depression, and poor response to psychosocial interventions. There is a critical need to develop a mechanistic understanding of the link between social disconnection and suicidality, identify biological targets, and address targets with scalable interventions. The investigators developed a novel psychotherapy, Engage & Connect, aimed to improve functions of the Positive Valence System (PVS) that are impaired in suicidality through increased engagement in rewarding social activities. This study will use state-of-the-art precision imaging methods and clinical measures to evaluate brain- and behavioral changes in the PVS during psychotherapy.

Participants will:

• Be randomly assigned to 9-weekly sessions of either Engage & Connect therapy or Symptom Review and Psychoeducation
• Complete 4 research assessments
• Complete 3 MRI scans

Inclusion Criteria:

• Ages aged 50-80 [stratified so that 50% are older than 65]
• Endorsement of Suicidal Ideation [Structured Clinical Interview for the Diagnostic and Statistical Manual for Mental Disorders-5 (SCID-5) Suicide Item (Item 9) with a score of 2
• Major Depressive Disorder as determined by the SCID-5
• Depression Rating Scale [Montgomery-Åsberg Depression Rating Scale (MADRS)] score of 16 or greater.
• Mini Mental Status Exam (MMSE) equal or greater than a score of 23
• Off antidepressants or on a stable dose of an antidepressant for 8 weeks and do not intend to change the dose in the next 10 weeks, without individual psychotherapy services during the study period.
• Capacity to provide consent for research assessment and treatment.

Exclusion Criteria:

• Intent or plan to attempt suicide in the near future.
• History or presence of psychiatric diagnoses other than major depressive disorder without psychotic features, generalized anxiety disorder, or specific phobia.
• Use of psychotropic drugs or cholinesterase inhibitors other than use of 0.5 mg or less of lorazepam daily up to seven times per week.
• Neurological disorders (dementias, amnestic and multidomain Mild Cognitive Impairment, Parkinson's disease, epilepsy, etc.).
• Acute or severe medical illness in the past 3 months (metastatic cancer, multiple sclerosis, decompensated cardiac, liver or kidney failure, major surgery, stroke or myocardial infarction, cardiac, renal, or respiratory failure; severe chronic obstructive pulmonary disease, etc.) that may be the primary cause depressive symptoms, influence brain systems of interest, or impact ability to participate in the study.
• Contraindications to MRI scanning including cardiac pacemaker, heart valve replacement, vascular stent, insulin pump, cochlear implant, any other metallic biomedical implant contraindicating to MRI, and claustrophobia.](streamdown:incomplete-link)

Individual participant data that underlie the results reported in publications, after de-identification, as well as study protocol, treatment manuals, statistical analysis plan and informed consent. The investigators will also share the fMRI tasks and analytic code by request with all interested researchers.

After the investigators publish the main results, they will make de-identified data available to other researchers, under a data-sharing agreement overseen by the DSMB, and in compliance with policy of the IRB and NIMH.

Investigators whose proposed use of the data has been approved by an independent review committee identified for this purpose. All researchers requesting data will commit to using the data solely for research purpose; secure the data; return or destroy it once analyses are completed; do not share it with other researchers.