Brief Trial of ACT-i for Adults With Chronic Insomnia

This is a prospective, randomized-controlled trial that assesses the efficacy of a brief Acceptance and Commitment Therapy (ACT-i), compared to an attentional control group, in adults with chronic insomnia. The interventions will be evaluated for their impact on insomnia severity, cognitive function, depression, anxiety, psychological flexibility, and sleep beliefs - measured before treatment, two weeks after and at a three-month follow-up.

Inclusion Criteria: * clinical/ subclinical diagnosis of chronic insomnia either already diagnosed by a professional, or identified with SCISD-R by our team of clinicians * age over 18 and older, but not over 59 years old; * minimal/ mild symptomatology of depression (scores ≤ 9 on PHQ-9) and/ or anxiety (scores ≤ 9 on GAD-7) or as diagnosed with SCID-5-CV; Exclusion Criteria: * diagnosed with a neurological degenerative disorder, or any moderate/ severe psychiatric disorder; * diagnosed with other sleep disorder (e.g., sleep apnea, restless legs/ periodic limb movements, circadian-based sleep disorder); * diagnosed with cognitive impairments; * unable to understand Romanian; * unable to attend to online-sessions (e.g., no laptop, microphone, camera);