Cognitive Behavioral Therapy for Insomnia (CBT-I) is the internationally preferred non-pharmacological therapy for the treatment of insomnia [2] . Traditional protocols for CBT-I often contain five main elements, as detailed below ( Table 3 ).

Table 3. Elements in current CBT-I protocol.

In our work, we noticed that participants frequently reported difficulties in putting the cognitive aspects of CBT-I into practice, and we proposed that people would benefit by adding specific learning paths to the valuable components of the usual CBT-I program.

The IT-I program has been built on the usual CBT-I elements [1] and extends it with elements of an integrative and systemic approach. An overview of the program per session is included in Table A2 . Figure 1 shows the major behavioral measures and cognitive techniques as program elements that act upon the participant’s disruptive behavior and disruptive arousal. Behavior and cognition together influence the two processes that shape an adequate sleep/wake cycle [5] . These two processes work together and mutually influence each other and prepare a person for sleep or wake: The homeostatic sleep drive regulates the internal need for sleep and the circadian system acts as a master clock, following sunrise and sunset, wherever on earth one may be. In Figure 1 , the extensions are printed in Bold & Italic.

It is expected that the extension with exercises, including sensory-motor stimuli, addressing the mirror neuron system, and Mental Contrasting with Implementation Intentions (MCII), will create opportunities to relearn sleeping. Some examples of exercises are briefly described in Table 4 .

Table 4. Examples of exercises.

To help participants regulate their behavioral and cognitive change, Mental Contrasting with Implementation Intentions (MCII) [11] was introduced in the program. Mental contrasting is a way of thinking about a future desired situation that contrasts with the current reality. It includes cognitive, motivational, and neural mediators. The introduction of sensory-motor stimuli within the MCII approach activates the mirror neuron system [12] . Sensory-motor stimuli encompass physical movements and visual, auditory, smell, touch, and proprioceptive inputs. The effect of mirror neurons comes through participating in exercises, but also when observing exercises and accompanying emotions are observed when performed by a facilitator or other participants. Repetition of one’s own practices and observation of others’ performance strengthens the neural pathways and helps to develop an automatic stimulus-response pattern [12] [13] . This type of learning is coordinated in an interplay of the mirror neuron system and brain networks [14] . Together the different routes and access points to embedded information and experiences facilitate the application and thereby initiate or support change. Another extension to the program is the exercise of learning to handle nightmares through Imagery Rehearsal [6] . It starts with first writing the nightmare, changing it by adapting the participant’s role and position in the story, and learning the new version by heart.

Furthermore, the program entails various relaxation exercises such as a focus on breathing, progressive muscle relaxation, virtual relaxation, and mindfulness. Participants initially participate in all types of relaxation and practice them daily at home to finally choose their preferred method. It is stressed that frequent exercise is required to be able to apply a technique automatically in stressful circumstances. It can be helpful for some to add a (virtual) image, scent, or motor action such as caressing a cuddly toy or fresh pillow.

To evaluate the efficacy of this IT-I program a qualitative multi-method was used: the program was preceded and concluded, baseline and post-treatment, by interviews and scoring on the Insomnia Severity Index (ISI). The ISI is a validated questionnaire used to measure the severity of insomnia at baseline and at the end of the intervention [15] . The interview at baseline provided context information, history of sleep, information about comorbid conditions, and the use of sleep medication. In the post-treatment session, the participants reflected on the learning process, the outcome, and the plan to anchor the results. A post-treatment inventory was emailed 3 months after the end of the program to gather information on the participants’ subjective sleep perception. This inventory was replied to by 19 participants. This study did not collect information on other health management or evaluations participants underwent during the treatment.

For analysis and interpretation of the obtained ISI scores, we refer to Morin et al. [16] ( Table 5 ).

Building on the categories developed by Morin et al. [16] , a cut-off score of 10 points was used, which is the proposed score for a population-based sample. To conclude on the clinical effect of the therapy, a change of >7 was considered significant [16] [17] . At the end of session 1 the participants were given the assignment to use a sleep/wake diary for at least for two weeks to picture their daily sleep/wake pattern. Additionally, their subjective assessment of their sleep quality, “How do you feel the day after” could be indicated by selecting one out of three emojis. Participants were instructed to fill the diary between 30 - 60’ after awakening to avoid the effect of morning inertia. Building on the available information such as Sleep Onset Latency (SOL), Time In Bed (TIB), and Wake After Sleep Onset (WASO) provided by the participants, each of them received dedicated advice to adapt their pattern including the moment to go to sleep, to get out of bed, and bed restriction. The use of the sleep diary was continued so long as the sleep was not satisfactory, which differed per person.

Inclusion in the treatment was based on an application to a federally funded convention for specialized psychological treatment. The convention fits the federal objective to avoid pharmaceutical treatment and lowers the threshold for participation in non-pharmaceutical treatment, by making this affordable. The convention rules include that:

Figure 2 shows the procedure from start to finish, including the participation screening. The therapy was delivered by three therapists, two psychologists, and one medical doctor-somnologist in the period from Q4 2022 to Q2 2024.

All involved participants consented by a written statement to have their data used for this study purpose.

Table 6 shows the participants, gender, age, and medication. A total of 18 people were taking non-sleep-specific medication which points to comorbid insomnia, e.g., depression, psychosis, and chronic pain. The diagnoses of comorbidity were obtained with informed consent from their medical records. Of the 32 people who started the therapy, 29 finished the complete intervention program with ISI scores.

Table 6. Participants, age, and medication post-treatment.

The below graph ( Figure 3 ) shows the ISI scores for the 29 participants, in blue at baseline before treatment and red at post-treatment. Given the limited number of male participants in the groups (n = 7) it was decided to refrain from gender-specific analysis.

The clinical significance of the observed change in scores is defined as “responsive to treatment” if a change from baseline to post-treatment is more than 7

Points [16] [17] . In our study, this was realized in 14 cases. Moreover, if an intervention leads to the final total score of <8 on the ISI, the participant is not suffering from insomnia [16] and in case of comorbid insomnia with substance addiction the participant is considered to be in complete remission [16] [17] . After the therapy, 7 participants arrived at a score < 8. From the initial 5 severe cases, 1 participant moved to moderate, 2 improved to sub-threshold level and 2 realized full remission ( Figure 4 ).

To support clinical significance the obtained data were used for some basic statistical calculations on significance.

Table 7. Calculations.

Table 7 shows the means at baseline and post-treatment, resulting in an average improvement in n = 29 of 7.2 points. The paired t-test including the two measurement sets, results in t = 8.08 and a p-value of 8.9E−10 or p < 0.01. Pearson’s correlation calculation shows a moderate negative correlation of r = −0.43 between age and the change of ISI results before/after treatment. This correlation could suggest that older people might benefit less from the therapy as was also concluded by Montgomery & Dennis in a Systematic Review [18] .

A summary of participants’ statements (n = 18) expressed after the therapy illustrates the appreciation for the program, a greater subjective sleep satisfaction, a decrease in the use of sleep medication, and an experience of improved functioning ( Table A1 ).