Mechanisms of Change in Cognitive Behavioral Therapy for Insomnia (CBTi)

The purpose of this study is to investigate the mechanisms of change in Cognitive Behavioral Therapy for insomnia (CBTi) in a sample of adults aged 50-65. This study aims to evaluate the pre-post treatment change in sleep, circadian rhythms, biomarkers, cognitive performance, and structural and functional magnetic resonance imaging scans (MRI).

Baseline Part 1:

* Online demographic and contact information
* Schedule Baseline Part 2 with the investigators via online link
* 1 week of daily sleep diaries

Baseline Part 2:

* Internet-based interview with the investigators to confirm study eligibility requirements
* Online self-report questionnaires
* 2 weeks of daily sleep diaries
* 2 weeks of sleep/wake assessment wearing a watch-like activity monitor (Actiwatch)

Objective Baseline:

* Single-night, diagnostic in-home sleep study, including and the following equipment:

  * Adhesive patch which will adhere to the arm
  * Sensor belts worn around the chest, fitted with nasal canula, pulse oximeter, and 3 electrodes which will adhere to the back of the neck and behind each ear
* Next-day appointment:

  * Neuropsychological assessment
  * Structural and functional magnetic resonance imaging scan (MRI)
  * Non-invasive blood pressure readings
  * Low-volume Blood draw (used to obtain genetic biomarkers)
  * Removal of adhesive patch
* Next-day evening (2-nights):

  * Consumable capsule
  * Sensor belt worn around the chest/abdomen Random Assignment: If it is determined the participant is eligible for the study, participants will be randomly assigned to one of the treatment groups (in-person, telehealth or internet delivered) or asked to wait to start treatment.

Treatment Phase I:

* Participants will complete up to 12 weeks of insomnia treatment or wait for treatment ("waitlist") 12-Week Post-treatment Part 1:
* Complete 2 weeks of an online daily sleep diary and actigraphy
* Complete online self-report questionnaires

Objective 12-Week Post-treatment:

• Repeat "Objective Baseline" outlined above

Treatment Phase II (WLC):

* Treatment will start for participants who had been assigned to the waitlist condition 3-Month Follow-Up:
* Complete online self-report questionnaires

Eligibility Criteria:
Inclusion Criteria:

* Aged 50-65
* Normal hearing with or without hearing aids
* Ability to speak and read English and ability to give informed consent
* Possession of a computer with video and audio capabilities
* Meets DSM-5 Criteria for Insomnia Disorder
* Internet speed sufficient for participating in teletherapy (e.g., Zoom Health) or SHUTi (for iCBTi group)
* MoCA scores ≥24 will be deemed normal cognitive status and considered eligible for study participation and/or assessed by the ability to comprehend the baseline screening questionnaires
* Willing to refrain from new external behavioral health or medication treatment for issues pertaining to sleep during participation in the study
* Indication that the individual plans to be in the area for the 6 months following the first baseline assessment

Exclusion Criteria:

* Failure to meet the above "inclusion criteria"
* Current circadian rhythm disorder, sleep deprivation, or hypersomnia and related sleep disorders (assessed with clinical interview and/or self-report) as CBTi has not been validated in these populations. Verified by self-report and/or clinical interview (SCISD-R)
* Untreated sleep disordered breathing (e.g., obstructive sleep apnea) assessed by self-report, clinical interview, and/or diagnostic sleep study (i.e., baseline sleep study PSG)
* Failing to meet criteria for MRI scan (e.g., having metallic implants); see Pre-screen MRI Checklist for full list of exclusions for MRI scans.
* Fear/phobia of needles (conflict with blood draw) and/or small spaces (conflict with MRI scanner)
* Current suicide risk meriting crisis intervention as assessed by the Patient Health Questionnaire (PHQ-9) and/or disclosure of serious suicidal ideation
* Pregnancy (self-report, proposed instruments and treatments have not been validated in this population)
* Sleep efficiency \> 85%, assessed by the sleep diary
* Serious mental health diagnosis (e.g., bipolar disorder or psychosis) assessed by structured interview (M.I.N.I.)
* Currently engaged in evidence-based psychotherapy for Insomnia (i.e., Cognitive Behavioral Therapy) by self-report
* Failure to follow protocol (e.g., consistent "no show" for appointments, answering questionnaires dishonestly, refusal to complete more than 2 assessments \[e.g., fMRI and Neuropsych\])