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Open AccessOriginal Article

The Effects of a Single Relaxation Hypnosis Session on Mental Stress in Chronically Stressed Individuals

An Explorative Experiment

Published Online:December 16, 2022https://doi.org/10.1026/1616-3443/a000679

Abstract

Abstract.Background: Chronically stressed people often suffer from anxiety and depressive mood. Hypnosis is a technique that can induce a relaxation response and reduce negative stress symptoms. Objective: This explorative study investigated the impact of a single relaxation hypnosis session on stress-related psychological symptoms. Method: 47 suggestible, stressed individuals (87 % female) were randomized to a hypnosis group (n = 23, 20-minute hypnosis) or a control group (n = 24, 20-minute scientific documentary). Before and after the intervention, we assessed perceived stress, negative affect, anxiety, and depressive mood. Results: After the hypnosis intervention, depressive mood (d = 0.36) and state anxiety (d = 1.00) decreased, while negative affect remained stable (d = 0.04). Perceived stress was reduced in both groups. Conclusion: A single relaxation hypnosis session decreased stress-related symptoms in chronically stressed individuals. Our results substantiated the stress-alleviating effects of hypnosis.

Die Wirkung einer einzelnen Entspannungshypnose auf das psychische Wohlbefinden bei chronisch gestressten Personen. Ein exploratives Experiment

Zusammenfassung.Theoretischer Hintergrund: Chronisch gestresste Menschen leiden häufig unter Angstzuständen und depressiven Verstimmungen. Hypnose ist eine Technik, die eine Entspannungsreaktion hervorrufen und negative Stresssymptome reduzieren kann. Fragestellung: Das Ziel dieser Studie ist es, die Wirkung einer einzelnen Entspannungshypnose auf stressbedingte psychologische Symptome zu untersuchen. Methode: 47 suggestible, gestresste Personen (87 % Frauen) wurden in eine Hypnosegruppe (n = 23, 20-minütige Hypnose) oder eine Kontrollgruppe (n = 24, 20-minütigen Dokumentarfilm) randomisiert. Vor und nach der Intervention wurden Stressempfinden, negativer Affekt, Ängstlichkeit und depressive Stimmung erhoben. Ergebnisse: Nach der Hypnose war die depressive Stimmung (d = 0.36) und die Angstzustände (d = 1.00) reduziert, während sich der negative Affekt nicht verändert hatte (d = 0.04). Das Stressempfinden verringerte sich in beiden Gruppen. Schlussfolgerung: Schon eine einzelne Entspannungshypnose verringerte stressbedingte Symptome bei chronisch gestressten Personen. Unsere Ergebnisse untermauern daher die stresslindernde Wirkung der Hypnose.

Chronic stress can compromise psychological well-being of affected persons by reducing important resources (Kocalevent et al., 2013). This process can lead to a state of exhaustion that manifests in various psychological and affective aspects, like depressive mood, negativity, and anxiety (Weber & Jaekel-Reinhard, 2000). Over time, exposure to chronic stress increases the risk of a variety of mental and physical health issues, including fatigue, burnout, depression, and anxiety (Bale, 2006; Weber & Jaekel-Reinhard, 2000) as well as cardiovascular diseases (Strike & Steptoe, 2004), obesity, and type II diabetes (Kyrou et al., 2006). The prevalence of these stress-related health issues is increasing worldwide (Heinrichs et al., 2015), as is the need for effective prevention and intervention measures.

Hypnotic interventions as preventive and interventional measures are highly beneficial for individuals with persistent stress exposure. Hypnosis is “a state of consciousness with focused concentration and diminished peripheral awareness, distinguished by a heightened ability for reaction to suggestion” (APA definition; Elkins et al., 2015, p. 381). Hypnosis often refers to both the state of consciousness and the technique itself (Revenstorf, 2003). In the following article, we therefore use the word hypnotic intervention when the technique is concerned.

The ability to respond to suggestions is called hypnotic suggestibility. Hypnotic interventions use suggestions to induce a change in behavior, attitude, or perception in an individual (e. g., “You feel very relaxed right now”). However, individual differences in hypnotic suggestibility may influence the overall positive effects of hypnotic interventions: Lower suggestibility may diminish the individual benefits of hypnotic interventions (Johnson et al., 1996). Nevertheless, the evidence on the influence of suggestibility is inconsistent (e. g., Cardeña et al., 2013; Gruzelier et al., 2001).

Furthermore, hypnotherapy is a resource-oriented therapy approach used since the 19th century to benefit patients’ body, mind, and behavior (Sawni & Breuner, 2017). As a therapeutic technique, it has many aims, including activating and strengthening positive emotional resources through reinforcement and re-experiencing these positive emotions in trance. The latter is achieved through suggestive messages repeated to stimulate positive effects, such as reducing anxiety and chronic perceived stress (e. g., Fisch et al., 2017; Hammond, 2010). For example, in a Randomized Controlled Trial (RCT), Fisch et al. (2020) observed a reduction in perceived stress (measured with a visual analog scale) after 5 weeks of group hypnotherapeutic intervention (five weekly sessions) and a 12-week follow-up, indicating an enduring stress-al‍leviating effect from a multiple session hypnosis intervention. Another RCT showed that 2 weeks of listening to a hypnosis intervention consisting of progressive relaxation, imagery, and anchoring significantly reduced stress and burnout symptoms (Cardeña et al., 2013). Thus, hypnotic interventions are also effective in alleviating preclinical stress symptoms, such as elevated state anxiety (d = 0.71; Bongartz et al., 2002) and subthreshold depressive mood (d = 0.52; Milling et al., 2018) at a perceptual level.

A relaxation hypnosis is characterized by the use of relaxing images (e. g., forest, sea, mountains) to stimulate all the senses (e. g., olfactory: “… simply breathing the fresh air of the sea, and a feeling of looseness occurs …”). A relaxation hypnosis allows the induction of a physiological relaxation response as a counterpart to a stress response in the body (Kossak, 2000). As there is much research on the stress response evoked in the laboratory (e. g., Hellhammer & Schubert, 2012), a relaxation hypnosis may also be appropriate in the laboratory setting to explore the previously poorly characterized relaxation response at the cognitive, emotional, and physiological levels.

There is physiological evidence for the benefits of a single session of a hypnotic intervention on the stress response, such as a reduced heart rate (Yüksel et al., 2013), altered brain activity and connectivity (Landry et al., 2017), as well as reduced stress hormones (Bongartz, 1996). However, there are few methodologically rigorous studies on the short-term effects of single-session hypnotic interventions on stress perception and well-being. For example, some existing studies on this topic did not include a control group, and others did not clearly distinguish hypnotic interventions from other techniques or did not consider suggestibility as a confounding variable (Airosa et al., 2011; Houghton, 1996).

To address these limitations, in this randomized controlled experiment, we aimed to explore the short-term effects of a single session of relaxation hypnosis on the preclinical negative consequences of stress, acute perceived stress, negative affect, subthreshold depressive mood, and anxiety compared to a control activity (i. e., watching a TV documentary) in individuals with subjectively high stress levels. We assume a reduction in perceived stress, depressive mood, anxiety, and negative mood, as well as an increase in perceived relaxation. The study was conducted as a part of the project “HypnoTreat” at Ulm University, which explores the change of biomolecular parameters through hypnosis (cf. Karrasch, Matits et al., 2022). In addition to biological outcomes (mitochondrial respirometry, blood count, inflammatory parameters), psychological parameters were collected to investigate the research question addressed here. Previous hypnosis studies mostly investigated younger participants: Five of the nine studies in the systematic review of Fisch et al. (2017) reported an age range of 20 – 25 years, and three referred to a cohort of 30 – 42 year-old participants. In the present study, we recruited a moderate to high suggestible adult cohort (age range 28 – 80) with persistent stress from caregiving, high job demands, and the COVID-19 pandemic (Appendix A, Table A1).

Methods

Participants

We screened 90 subjects, recruited through advertisements in newspapers and flyers, via telephone for the following exclusion criteria: age of at least 18 years; increased stress exposure in the past month (see below for details); German native speakers; inflammatory or epileptic disease; current psychotherapy; psychotic or personality disorders; as well as current alcohol or drug intoxication. In light of these criteria, we further screened 71 of the 90 participants for suggestibility in a preceding group testing. Only suggestible individuals, i. e., those scoring > 6 in the Harvard Group Scale of Hypnotic Susceptibility Form A (HGSHS:A) and > 24 in the Determination of Emotional Resource Potential (DER) questionnaire, were invited to participate in the main experiment (Bongartz, 1982; Wolf & Bongartz, 2009). In the case of incongruency between the two questionnaires, we used the clinical judgment of the achieved hypnotic experience by the present hypnotherapist as an additional criterion. The final sample consisted of 47 participants (87 % women) with a mean age of 59 years (SD = 11.70; range 28 – 80 years; Mdn = 60, 25 %-quantile = 53, 75 %-quantile = 68) and a perceived stress level (PSS-14 sum score) in the past month of M = 28.76 (SD = 1.28). displays the flow diagram of the study. For a detailed overview of the sociodemographic characteristics, see Appendix A, Table A1. The 47 participants were block-randomized via coin toss by age and sex into parallel groups in a 1:1 ratio, with 23 assigned to the hypnosis group and 24 to the attention-control group. The study coordinator was in charge of this randomization.

Figure 1 Participants’ flowchart.

Experimental Protocol

Participants took part in a group testing to assess their suggestibility (HGSHS:A, see Measures section) and emotional resource potential (DER; see Measures section) before being selected for inclusion in the study. Each group consisted of five to eight participants, and the test lasted about 2 hours in a quiet room at Ulm University. After filling out the consent form, the participants were played the audio file with the 30-minute hypnosis text of the DER via speakers. The participants were seated in comfortable chairs. At the end of the hypnosis tape, the experienced emotions were rated, followed by a break of about 15 minutes, during which the participants were asked to go outside. A questionnaire on sociodemographic information was then completed. Afterwards, while in a sitting position, the participants listened to the audio file of the HGSHS:A (60 minutes). They were then asked to complete the questionnaire while listening to the instructions of the experienced hypnotherapist, who was present during the whole procedure and noted the clinical observations. After the evaluation of the questionnaires by the study staff, the participants were informed via telephone whether they could participate in the main experiment.

The main experiment took place at Ulm University in an individual setting from January to November 2020. Participants were invited to the testing between 8:00 a.m. and 9:00 a.m. After filling out psychological questionnaires, participants rested for 15 minutes. During this time, they were instructed to lie down comfortably. Afterward, the hypnosis group listened to a 20-minute relaxation hypnosis audiotape via headphones and was instructed to close their eyes during the hypnotic intervention. The tape suggested a walk along the beach and employed traditional trance speech patterns found in traditional societies based on a cross-cultural study by Bongartz and Bongatz (2019; for more information, see Appendix B and Table B1). We validated in a preliminary study that this language pattern increases imagination, reduces cognitive activation, and enhances the hypnotic state, compared to the modern hypnotic language (Karrasch, Jung et al., 2022). In the control condition, the same protocol was conducted as in the experimental group, except that the intervention was a 20-minute documentary about the origins of the universe and life. In this way, we wanted to create a comparison between a relaxation hypnosis and a natural everday relaxing situation. In addition, we chose content of the video which was neutral in nature to minimize possible emotional stimuli.

Immediately after the intervention, participants rated their relaxation experience and repeated the mood and emotional state questionnaires. While both the participants and the investigator were aware of the allocated experimental group, outcome assessors and data analysts were blinded to the allocation. The study was approved by the ethics committee of Ulm University and registered in retrospect on 7 December 2021 at https://www.drks.de (DRKS00027356). Written informed consent was obtained from all participants. Participants received reimbursement of €10 for each testing, and they received the hypnosis audiotape for their personal use.

Measures

Inclusion and Control Variables

Stress

The stress level of the participants was assessed in three steps: (1) The advertising for the study targeted people who subjectively felt chronically stressed. (2) To assess the current perceived stress level in the context of their subjective chronic stress, the screening item “On a scale of 1 – 10: How stressed do you currently feel?” ranging from 0 (not at all) to 10 (extreme), was queried in the telephone screening: Chronically stressed participants with a current perceived stress level of ≥ 5 were invited to participate in the study. (3) After enrolment, perceived stress within the last month was assessed with the German translation of the Perceived Stress Scale (PSS-14; Cohen et al., 1983), which is commonly used for assessing chronic stress levels (e. g., Bay & de-Leon, 2011; Covassin & Bay, 2012; Harville et al., 2009; Khosrowabadi et al., 2011). On 14 items, participants reported the degree to which they experienced situations as excessively uncontrollable and overwhelming in the last month. Responses were recorded on a 4-point Likert scale ranging from 0 (not at all) to 4 (very much) and aggregated to a sum score (range: 0 to 56; Cronbach’s αpre = 0.91, Cronbach’s αpost = 0.92).

Suggestibility

Moderate to high suggestibility was defined as an inclusion criterion for study participation. Suggestibility was assessed with the German version of the HGSHS:A, a screening of suggestibility within groups (Bongartz, 1982; Shor & Orne, 1963). It consists of 12 hypnotic suggestions with motor and cognitive tasks (e. g., inability to open the closed eyes because they feel so heavy), to which the participants listened via audio file in small groups under the instruction and supervision of the instructor. Afterward, they were asked whether they followed these suggestions. A sum score was calculated (range: 1 to 12, Cronbach’s α = 0.67 to 0.73) to validate the suggestibility of the participants.

Emotional Resource Potential

To measure whether emotional experiences can be perceived during hypnosis, we conducted the German DER questionnaire (Wolf & Bongartz, 2009) before including the participants. It consists of six short narratives of nature scenes for activating six emotions (e. g., strength, security, hope). After listening to a 30-minute audio file with six narratives describing nature scenes, the participants had to rate whether they were able to feel the described emotional experience and whether they were familiar with this feeling in their everyday life on a 9-point Likert scale from 0 (not at all) to 8 (very good). The DER is a reliable and valid questionnaire to investigate emotional resources (Cronbach’s α = 0.75 to 0.89; Wolf & Bongartz, 2009).

Intervention Experience / Distraction

After the intervention, the participants rated the depth of hypnosis or, respectively, the absorption through the documentary. Additionally, they reported possible distraction by external stimuli or internal states (e. g., thoughts, emotions) on a visual analog scale (VAS) ranging from 0 (not at all) to 10 (extremely). Moreover, they were asked to note down their internal observations (e. g., “I felt my body temperature lower”).

Outcome Variables

Acute Stress and Relaxation

Perceived acute stress was assessed with two items (“I feel stressed right now” and “I am under pressure”) using a VAS ranging from 0 % (none) to 100 % (maximum). Ratings of both items were averaged to achieve a total score of acute perceived stress. Acute relaxation was assessed with another two items (“I am relaxed right now” and “I can shut down very well at the moment”). The items were averaged to calculate a mean score of acute perceived relaxation.

Negative Affect

The negative emotional affect was measured using a subscale of the German Positive and Negative Affect Schedule, state version (PANAS-S; Watson et al., 1988) that included ten adjectives (e. g., upset, scared) describing ten negative feelings and sensations. Participants responded on a five-point Likert scale from 1 (not at all) to 5 (extremely). For the measurement of the negative affect, the mean of the items related to the subscale was calculated, ranging from 1 to 5 (Cronbach’s αpre = 0.62, Cronbach’s αpost = 0.56). The change of negative affect in the control condition was additionally used to examine the emotional neutrality of the scientific documentary.

Depressive Mood

The German Beck’s Depression Inventory (BDI; Beck et al., 1961) was used to assess the participants’ self-reported depressive mood. The BDI consists of 21 statements on depressive symptoms experienced within the last week. Participants respond on a 4-point Likert scale ranging from 0 (e. g., I do not feel sad) to 3 (e. g., I am so sad and unhappy that I can’t stand it). All responses were combined to calculate a sum of scores (range: 0 to 63; Cronbach’s αpre = 0.85, Cronbach’s αpost = 0.85).

State Anxiety

State anxiety was measured with the state anxiety scale of the German State-Trait Anxiety Inventory (STAI-S; Laux et al., 1981). The STAI-S comprises 20 items (e. g., “I am excited”). Participants evaluated how they felt at that moment on a 4-point Likert scale ranging from 1 (almost never) to 4 (almost always). Responses were combined to a sum of scores ranging from 20 to 80 (Cronbach’s αpre = 0.84, Cronbach’s αpost = 0.91), with higher values indicating stronger state anxiety.

Data Analysis

The data were analyzed using R (R Core Team, 2020). Bivariate associations were examined with nonparametric Kendall’s τ rank correlations, as most variables were not normally distributed. Linear mixed effect regression models (using the R package lme4; Bates et al., 2014) with the two factors Group (hypnosis vs. control group) and Time (pre- vs. post intervention) were modeled to test for hypnosis-specific improvements (i. e., Group ⨯ Time interactions) in the outcome variables. Shapiro-Wilk tests were used to determine the normality of model residuals. The nature of significant Group ⨯ Time interactions was explored using post hoc linear contrasts (using the emmeans package for R; Lenth et al., 2021). Except for negative affect, all reported p–values were two-tailed with a significance level of α < .05. P-values of post hoc tests were adjusted for multiple comparisons according to the procedure of Benjamini-Hochberg (false discovery rate; Benjamini & Hochberg, 1995). To review the robustness of the results, we repeated the analyses adjusting for possible covariates (age, suggestibility, and sex). Table 1 summarizes the descriptive statistics for the outcome variables. Linear mixed effect regression models with random intercept were computed for each outcome variable (see Appendix C, Table C1). Except for negative affect, all models were statistically significant (p ≤ .025) and explained a small to medium proportion of the variance (R² = .023 to .250). The models indicated that at baseline, the intervention and control groups did not differ in any outcome variable (see )

Figure 2 Interaction plots for the stress-related outcome variables in the hypnosis and control group (pre- and postintervention). The depicted p–values refer to the interaction effects; *p < .050, **p < .010; State-Trait Anxiety Inventory state version (STAI-S); Beck’s Depression Inventory (BDI).

Results

Acute perceived stress decreased in both groups from pre to post treatment, F‍(1, 43.87) = 49.49, p < .001, ηp2 = 0.27, (), whereas acute relaxation, F‍(1, 44.17) = 11.07, p = .002, ηp2 = 0.24, () increased in both conditions with time. However, the reduction in perceived stress and the increase in acute relaxation in the hypnosis condition did not significantly differ from alterations in the control condition (no significant Group ´ Time interaction). Descriptively, there was a stronger reduction in acute stress in the hypnosis condition (see ). There were no significant main or interaction effects on negative affect (see Appendix C, Table C1).

Significant Group ´ Time interaction effects were found for both state anxiety () and depressive mood (). Post hoc tests indicated that state anxiety significantly decreased in both groups from pre to post treatment, although the decrease was stronger in hypnotized participants (pre-post mean difference: ΔPost-Pre = -8.78, SE = 0.35, pFDR < .001, d = 1.00) than controls (ΔPost-Pre = -4.14, SE = 0.53, p = .018, d = 0.37). Moreover, depressive mood significantly decreased in the hypnosis group (ΔPost- Pre = -2.65, SE = 0.63, pFDR < .001, d = 0.36) but not in the control group (ΔPost-Pre = -0.46, SE = 0.54, pFDR = .641, d = 0.09). A detailed overview of the results can be found in Table C1. We additionally explored which symptom clusters in depressive mood were influenced by relaxation hypnosis. Supplementary analyses (see Table C2) indicated that hypnotic intervention reduced the participants’ negative attitudes but did not influence their somatic symptoms and performance difficulties.

Table 1 Psychological outcome parameters pre- and postintervention

Potential Covariates

All analyses were repeated to review the robustness of findings while adjusting for age, sex, BMI, and suggestibility, respectively. The covariates BMI, suggestibility, and sex did not alter the pattern of the above results. There was a significant main effect of the emotional resource potential on negative affect, F‍(1, 43) = 6.38, p = .015, ηp2 = .13, indicating that individuals with greater emotional resources had a higher negative affect. Nevertheless, the emotional resource potential as a covariate did not alter the overall findings for negative affect.

Discussion

This explorative study indicates that as little as one session of relaxation hypnosis reduces stress-related states in the short term and has greater antidepressant and anxiolytic effects than a typical daily relaxing situation such as watching television. Acute perceived stress was reduced in both groups. However, the negative affect after hypnosis remained unchanged.

Essentially, our study demonstrates that one session of inducing relaxation through hypnotic intervention has a stress-relieving effect in chronically stressed individuals, thereby extending previous findings concerning the beneficial long-term effects of multiple-session relaxation hypnosis. Cardeña et al. (2013) reported a medium to large effect after 2 weeks of daily hypnotic intervention on perceived stress, and Fisch et al. (2020) found decreased perceived stress after 5 weeks of hypnotic intervention as well as at the 12-week follow-up. In both studies, the effects of the hypnotic intervention were assessed after a treatment period of 2 respectively 5 weeks. However, our study demonstrates that even a single session of relaxation hypnosis can significantly reduce stress symptoms, although the stress-relieving effect of the hypnotic intervention was not superior to the effect of watching a documentary. The task now for future studies is to determine whether these results are sustainable, and whether there is an advantage of hypnosis in long-term interventions.

Persistent stress can lead to an impairment of psychological well-being, which expresses itself, for example, in pessimism, helplessness, and excessive demands. In the long-run, persistent exposure to stress contributes to establishing negative cognitive schemata and ruminative thinking, which may favor the development of anxiety and depression (Hansch, 2021). It can be assumed that hypnosis may interrupt this negative process on two levels. First, on a physiological level, hypnosis-induced relaxation reduces the somatic components of stress by influencing hematological components and inflammatory activity (Karrasch, Matits et al., 2022). A hypnosis-induced reduction in inflammatory activity could counteract depressive and anxiolytic symptoms, since both depression and anxiety are associated with higher inflammation (Costello et al., 2019; Matits et al., 2022; Osimo et al., 2020). Second, hypnosis enables individuals to dissociate directly from feelings of being stressed, anxiety, and depression (Spiegel & Spiegel, 2004). From a neurophysiological perspective, it has been suggested that hypnotic trance leads to a transient decrease in prefrontal cortex activity (the transient hypofrontality hypothesis; Dietrich, 2003). Research from another field shows that transcranial magnetic stimulation of the dorsolateral prefrontal cortex leads to changes in the cognitive control network, which is involved in emotion regulation and may counteract depressive symptoms (Lantrip et al., 2017). This decrease contributes to a reduction in cognitive and emotional activity and may explain the detachment of feelings and cognitions during and shortly after hypnosis (Andò et al., 2021; Davidson, 2004; Gruzelier et al., 1984).

In this study, additional analyses indicated that, among the depressive symptoms, hypnosis specifically reduced the participants’ negative attitude, which is the cognitive component of depressive symptoms, but not somatic symptoms or cognitive performance difficulties, at least in the short term. This supports the hypothesis of a change in cognitive control networks through hypnosis. Further research is necessary to advance our understanding of the neurophysiological and biological processes underlying the hypnotic state. Besides, additional studies are needed to determine the minimal number of hypnosis sessions required to obtain positive changes and to sustain the beneficial long-term effects of hypnosis intervention even after session completion. These new findings incorporated into hypnosis therapy could significantly optimize the therapeutic effect.

Here, we assessed depressive mood with the BDI, which measures depressive symptoms over the past week. Since the pre and post measurement refer to the same period (past week), it cannot be assumed that symptoms have actually changed. A change in self-reported depressive symptoms, as shown in the present results, can rather be explained by a change in either the perception of the symptoms during the past week or a change in the current feelings of depressiveness, exhaustion, fatigue, and lack of energy. For example, the former was observed in a study by Caponnetto et al. (2019), who showed the perception of stress can be changed by a stress management program using autogenic training. In addition, it has been demonstrated that hypnosis can improve current feelings of emotional exhaustion and perceived stress (Fisch et al., 2017, 2020). This could make individuals feel less tired and exhausted.

Strengths and Limitations

As the individuals interested in participation were not skeptical about hypnosis, there might have been a self-selection bias regarding the participants’ openness to the intervention. In Western societies, women are typically more interested in complementary medicine and relaxation techniques than men. Therefore, this present study and previous studies with convenience samples enrolled higher proportions of female than male participants (Fisch et al., 2017, 2020; Karrasch, Jung et al., 2022), which limits the study’s generalizability. Individual differences in suggestibility might have influenced the effects of hypnosis, which previous studies have often disregarded (e. g., Kiecolt-Glaser et al., 1986). To control for this, we decided to enroll exclusively participants who were sufficiently suggestible according to multiple criteria. Since some established suggestibility questionnaires have received criticism (see review in Acunzo & Terhune, 2021), this study additionally surveyed emotional resource potential as a predictor of experiencing a hypnotic trance and included the clinical judgment of an experienced hypnotherapist. A further strength is the heterogeneity of the participants: By recruiting chronically stressed adults of all ages, not just students, we provide a more representative sample. In previous studies, the definition of the assessed stress was often unclear and inconsistent. Therefore, in this study, we selected chronically stressed participants using the PSS-14 as a well-established stress questionnaire. A further strength of the study was the use of a previously validated hypnosis text (Karrasch, Jung et al., 2022). This specific trance language proved to be more effective than modern and common trance languages in reducing cognitive activity and enhancing imagery during hypnosis.

Using a close to real-life control condition (i. e., watching a video) offers a means of comparing hypnosis with a common situation (i. e., watching television) in everyday life. We have now evidence that, although both activities are frequently judged as relaxing, hypnosis is superior to watching TV in the reduction in anxiety and depressive mood, although both do reduce perceived stress. However, in hypnosis research, a hypnotic intervention is commonly compared with an audio tape as both rely on the auditory modality. This has the disadvantage of introducing an artificial control condition (that might also be too similar to the hypnotic intervention). Further, our preliminary assumption of the documentary being emotionally neutral is being supported by the fact that there was no change in negative affect in the control group (as measured by the PANAS-S) from before to after watching the TV documentary.

Moreover, the relatively low BDI and PANAS-S scores of the present sample indicate low depressed mood and negative affect, suggesting that the sample may not be highly emotionally distressed because of increased subjective stress. Therefore, the representativeness of the results, especially concerning a chronically stressed population, is limited. For practical therapeutic work, it is particularly important to investigate the long-term effects of hypnosis in clinical cohorts (with high levels of anxiety and depression) on markers of chronic stress and clinical symptom reduction.

Conclusion

This explorative experimental study suggests beneficial effects of a single session of relaxation hypnosis on perceived stress, emotional affect, state anxiety, and depressive mood in chronically stressed individuals. Our findings highlight the potential of hypnotic intervention as an affordable, readily available preventive measure to benefit the psychological well-being of chronically stressed individuals. Subsequent studies need to investigate the number of hypnosis sessions needed to establish a positive psychological change in long-term interventions. In addition, the underlying biological effects should be investigated to address them more specifically through multimodal treatments.

Appendix A

Sample Characteristics

Table A1 Sociodemographic characteristics of the participants

Appendix B

Transcript of the Hypnosis Text With Traditional Trance Language Used in the Study

In a cross-cultural comparison of traditional trance texts, Bongartz and Bongartz (2019) showed that all trance rituals are based on the same formal structure: Mainly the texts consist of two-line descriptions of a scene or an event and of multi-line text units (up to 10) expressing requests, wishes, or emotional experiences. The following text was developped by one of the coauthors (WB) and was used in the study as hypnosis condition (20 minutes):

„Bitte die Augen schließen und sich einmal Zeit nehmen, da zu sein. Und da zu sein lässt sich leicht erfahren über die Haltung des Körpers insgesamt. Dazu mit geschlossenen Augen eine bequeme Körperhaltung einnehmen und sich dabei des Körpers von oben nach unten bewusstwerden … Gut … Dann bitte einmal tief einatmen, kurz Luft anhalten und dann beim Ausatmen, so eine Oberflächenspannung weg atmen … Genauso … Und es nun der Atmung überlassen, eine beginnende Ruhe zu vertiefen … Einfach dem Atemrhythmus zuschauen, wie er das macht … Und wenn man dem Atemrhythmus genau zuschaut, ist es überraschend, wie präzise die begleitenden Bewegungen im Brustbereich wahrnehmbar sind … Und dann möchte ich dazu einladen, einem anderen Rhythmus zu begegnen …

Und wer hat es nicht schon erlebt, alleine vor einem Meer zu stehen und hier auf einen anderen Rhythmus zu treffen? Auf den Rhythmus der Wellen … Der Wellen, die hier schon seit Jahrtausenden ans Ufer schlagen … Ein zeitloses Kommen und Gehen der Wellen … In einem gleichmäßigen Rhythmus. Und je mehr das zeitlose Kommen und Gehen der Wellen beobachtet wird, umso mehr verschwimmt das Vorher und Nachher … Umso mehr verschwimmen das Gegenwärtige, Künftige und Vergangene im Rauschen des Wassers, das immerwährend kommt und geht … Und ein Raum der Zeitlosigkeit tut sich auf, der den Blick weitet für das unmittelbar Vorhandene, das im hellen Licht hier am Meer klar hervortritt …

Die riesige Weite des Meeres
Die Farbe des Meeres
Der Horizont … ganz hinten
Die Frische des Windes aus der Ferne
Der Geruch des salzigen, frischen Wassers
Die zunehmende Ruhe

Und der Körper kennt diese zeitlose Ruhe, die das Meer ausstrahlt.

Und die Ruhe des Meeres strömt dann in Schultern, Arme und Hände.
Eine tiefe Ruhe.

Die Ruhe des Meeres strömt in den Rücken.
Eine tiefe Ruhe.

Die Ruhe des Meeres strömt in den Brustbereich.
Eine tiefe Ruhe.

Die Ruhe des Meeres strömt in die Mitte des Körpers.
Eine tiefe Ruhe.

Die Ruhe des Meeres strömt in das Becken.
Eine tiefe Ruhe.

Die Ruhe des Meeres strömt in die Beine hinunter, bis in die Füße.
Eine tiefe Ruhe.

Und dann am Meer entlang schlendern … spüren, wie der Sand unter den Füßen dazu einlädt, freier zu gehen, ohne irgendwelchen Zielen hinterhereilen zu müssen … Die Leichtigkeit und Frische des Windes überträgt sich dabei auf den Körper. Die Bewegungen von Armen und Beinen sind frei und selbstbestimmt. Und mit dem freien Rhythmus der Bewegungen tritt eine Gelöstheit auf. Eine Gelöstheit, die den ganzen Körper löst und frei macht …

Und die Schultern lassen dann einfach los, Verspüren eine freie Gelöstheit.

Arme und Hände lassen einfach los, Verspüren eine freie Gelöstheit.

Der Rücken lässt einfach los, Verspürt eine freie Gelöstheit.

Der Brustbereich lässt einfach los, Verspürt eine freie Gelöstheit.

Der Bauch lässt einfach los, Verspürt eine freie Gelöstheit.

Der Beckenbereich lässt einfach los, Verspürt eine freie Gelöstheit.

Die Oberschenkel lassen einfach los, Verspüren eine freie Gelöstheit.

Waden und Füße lassen einfach los, Verspüren eine freie Gelöstheit.

Manchmal ist es dann angenehm, mit bloßen Füßen auf das Meer zuzugehen. Und im Wasser wird dann die Bewegtheit des Meeres an Füßen und Waden gespürt. Und dann wird die Atmung tiefer, nimmt sich Zeit, um die Weite und Frische des Meeres ganz zu erfassen.

Und die Frische des Meeres findet dann den Weg in die Brust.
Macht die Brust weit und frei.

Die Frische des Meeres verbreitet sich in die Brust.
Macht die Brust weit und frei.

Die Frische des Meeres füllt die Brust völlig aus.
Macht die Brust weit und frei.

Die Frische des Meeres erreicht das Bewusstsein.
Macht das Bewusstsein weit und frei.

Die Ruhe des Meeres und die freie Gelöstheit des Körpers bilden dann ein Fundament, bilden die Basis für eine tiefe Gelassenheit.

Und die Gelassenheit breitet sich im Rücken aus.
Und Sie müssen nichts tun.

Die Gelassenheit breitet sich in Schultern und Armen aus.
Und Sie müssen nichts tun.

Die Gelassenheit breitet sich im Brustbereich aus.
Und Sie müssen nichts tun.

Die Gelassenheit breitet sich in Becken und Beinen aus.
Und Sie müssen nichts tun.

Gut … Und wenn wir jetzt diese Phase beenden, ist sie natürlich nicht zu Ende. Die gemachten Erfahrungen bestehen weiter, auch wenn sich das Bewusstsein später auf andere Dinge richtet.

… Genauso wie der Atemrhythmus weitergeht, auch wenn Sie nicht darauf achten … Und wenn ich jetzt von 3 auf 1 zähle, nehmen Sie sich die Zeit, die Ihnen recht ist, um wieder die Augen zu öffnen … 3 … 2 … 1.

Appendix C

Results of the Main Analyses

Table C1 Results of linear mixed effect models for the psychological outcome variables

   

Supplementary Analysis for the Subcategories of the Beck′s Depression Inventory

Table C2 Results of linear mixed effect models for the subcategories of the Beck′s Depression Inventory (BDI)

We cordially thank Natascha Pye and Suchithra Varadarajan for language proofreading.

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