Studies recognize cognitive behavioral therapy for insomnia (CBT-I) as empirically effective; however, few studies have examined its therapeutic mechanism. This study attempts to remedy that gap by examining the mediation effects of cognitive behavioral factors on the improvement of insomnia symptoms. We extracted six studies after doing a literature search on PsycINFO, PubMed, CiNii, and medical online journals for the terms insomnia, CBT-I, mechanism, and mediator in both English and Japanese. Four studies indicate that dysfunctional beliefs about sleep, safety behavior, rise time variability, and pre-sleep arousal may mediate improvement of insomnia. This paper ends by discussing future research in understanding CBT-I mechanisms. It would be important for future studies to (a) develop assessments for cognitive behavioral factors about insomnia, (b) examine mediating effect including some cognitive behavioral factors, and (c) develop intervention techniques to safety behavior.

While habit reversal (HR) has been shown to be effective for treating tics, scholars in both Japan and elsewhere have noted a small number of documented cases involving severe vocal tics. In this study, we conducted behavioral therapy incorporating HR with a client experiencing severe vocal tics in the form of shouting. We then verified the effects using single-case study research methods. The client was a woman in her 40s, and she started behavioral therapy after a month of medication following hospitalization did not produce a complete response. We collected data for five hours per day over four days to establish a baseline, finding an average shouting frequency of 93.5 times per day. The intervention consisted of 15 minutes of competing reaction training with a psychologist, using throat clearing whenever shouting occurred; the client was asked to practice this training daily. The intervention was conducted 10 times over 25 days. The frequency of shouting declined considerably after the intervention, and the shouting stopped completely four weeks later, the client was then discharged. Three years after the intervention, no recurrence of symptoms has been observed. This study showed that HR was effective for severe vocal tics.

This case study performed acceptance and commitment therapy on a woman with head discomfort that prevented her from going out alone or with her daughter. The intervention improved her behaviors of leaving her home, as measured by three dimensions: departure frequency, distance from the house, and number of the places visited. Results revealed improvements in all dimensions, suggesting the effectiveness of ACT for clients with difficulties leaving home. The effectiveness of the intervention and the usefulness of measuring behaviors through several dimensions was discussed.