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Plot represents the relationship between change in NK cell functioning and subject humor response (24).
Source publication
This is the final article in a four part series reviewing the influence of humor and laughter on physiological and psychological well-being. This final article reviews the evidence for the effect of sense of humor, exposure to a humor stimulus and laughter on various immune system components, with a focus on the effects of laughter on natural kille...
Context in source publication
Context 1
... Scale (P < 0.05). This finding indicated that only the subjects who laughed out loud during the humor video had significantly increased immune function following the intervention. Persons who just smiled or did not have observable responses to the humor video did not have positive changes in immune function. This finding is demonstrated in Fig. 1, indicating a significant relation- ship between the amount of laughter and change in immune function for persons in the humor group. Similar to findings from other studies, there was no connection between sense of humor (as measured Situ- ational Humor Response Scale and the Multidimensional Humor Scale) and change in any of the study ...
Citations
... Laughter also contributes to psychosocial and physical health, and several studies [10][11][12][13][14][15] have shown that it can help alleviate anxiety and depression. Physiologically, laughter reduces stress hormones [6,14] and increases T lymphocytes by activating natural killer cells, which causes an upsurge in white blood cells and immunoglobulin levels, thus increasing a body's immunity [15][16][17]. ...
... Laughter also contributes to psychosocial and physical health, and several studies [10][11][12][13][14][15] have shown that it can help alleviate anxiety and depression. Physiologically, laughter reduces stress hormones [6,14] and increases T lymphocytes by activating natural killer cells, which causes an upsurge in white blood cells and immunoglobulin levels, thus increasing a body's immunity [15][16][17]. Laughter also lowers blood pressure: it reduces vasoconstriction through a decrease in the breakdown of nitric oxide-a vasorelaxant substance-and raises blood glucose levels by reducing cortisol [14,18,19]. Laughter therapy is non-invasive, non-pharmacological, and relatively easy to implement; it is thus considered an effective complementary treatment that can reduce the intensity of many diseases [20] and is expected to improve the health of middle-aged adults [21]. ...
Background
Disorders associated with mental health significantly impact disability-adjusted life year values and represent an ongoing problem in stressed societies. Worsening mental health also affects cognitive function and quality of life. Increasing attention has thus been attracted to preventive measures for mental and brain health in daily life. This has created a growing interest in care using laughter. This study assessed the effects of a short-term, laughter-based intervention on the mental health and cognitive functions of middle-aged adults.
Methods
The study applied a single-blind, crossover-controlled trial design. Cognitive tasks (e.g., digit vigilance) were performed after participants viewed a video clip of approximately four minutes (comedic or control video), and the resulting scores were treated as the primary endpoint. The secondary endpoints included cerebral blood flow in the dorsolateral prefrontal cortex (measured using NIRS), heart rate variability (calculated from ECG), subjective mood assessment, and salivary stress biomarkers (e.g., α-amylase activity).
Results
The study was conducted on 25 healthy Japanese-speaking adults aged 40 to 65. Results revealed a significant increase in digit vigilance scores. Compared to viewing the control video, participants evinced a trend toward an increase in serial seven subtraction scores after viewing the comedic video. No significant differences were found for other cognitive tasks. The cerebral blood flow was also significantly higher in the dorsolateral prefrontal cortex during the cognitive tasks performed after the participants viewed the comedic video compared to the control video. The outcomes of heart rate variability, subjective mood state assessment, and salivary stress markers also suggested that the comedic video intervention could subsequently contribute to the activation of parasympathetic activity and reduce psychological stress levels.
Conclusions
The outcomes indicated that interventions using short comedic videos can improve focus and may reduce psychological stress. These results support the clinical benefits of humor, which can be utilized as a simple, non-invasive approach to promoting the health of middle-aged adults.
Trial Registration
The study was approved by the ethics committee of Kirin Holdings Company (No. 2020–014) and registered in the University Hospital Medical Information Network (UMIN) database (Registration No. UMIN000043332; http://www.umin.ac.jp/ctr/) on February 15, 2021.
... 28 In addition, laughter temporarily increases salivary immunoglobulin A (IgA) levels, suggesting that laughter may enhance certain aspects of immune function. 29 Laughter is also known to have positive effects on health 30 and has been shown to reduce stress hormones. 31 In a six-year follow-up cohort study, shared social interactions, through laughter, were associated more strongly with a reduced risk of functional disability than laughing alone (e.g., laughing while watching television). ...
Objectives: This study aims to investigate the association between frailty and oral function in rheumatoid arthritis (RA) patients and to identify practical markers for early frailty detection and potential intervention strategies.
Patients and methods: A multi-center observational cohort study (T-FLAG) included a total of 661 RA patients (475 males, 186 females; mean age: 68.5±13.5 years; range, 18 to 100 years) between June 2023 and August 2023. Frailty was assessed using the Kihon Checklist (KCL) (frailty: score ≥8). Oral function scores were based on Question 13 (“difficulty eating hard foods”), Question 14 (“choking”), and Question 15 (“dry mouth”) of the KCL. Receiver operating characteristic (ROC) curves were generated to assess the association between frailty and oral function scores. Multivariate logistic regression was used to analyze factors associated with oral function.
Results: Among the 661 participants, 39.5% were frail. Frailty rates tended to increase with increasing oral function scores. The optimal cut-off score for oral function corresponding to frailty was 2 points, with a specificity of 89.2% and a sensitivity of 54.8%. Multivariate analysis identified age and Health Assessment Questionnaire-Disability Index (HAQ-DI) as significant factors associated with oral function decline (i.e., a total score of ≥2 for Questions 13-15 of the KCL).
Conclusion: Frailty is strongly associated with oral function decline in RA patients. This finding highlights the importance of monitoring the oral function of RA patients, since it not only reflects physical function, but also serves as a potential marker of frailty. Targeted interventions to improve oral function may play a vital role in reducing frailty risk and enhancing the overall well-being of RA patients.
... In the clinical context, laughter describes its meaning in various performances related to the release of psychic energy, stress, anxiety, depression, and interpersonal relationships [4,6,24,35,45]. Especially in the counseling context, the presence or absence of laughter could ...
... The results of our study can be extended in that we observed the role of cheerful laughter by referring to the significant relationship between client laughter and session outcomes. Addressing variables such as a sense of humor or cheerfulness in therapy sessions may suggest positive effects resulting from happiness and may be linked to mitigating the effects of stress [2,4,14]. Based on this assumption, cheerful laughter can be expanded to be a major variable for predicting session outcomes. ...
Considering the growing interest in VR psychotherapy, this study investigated the relationship between client laughter and session outcomes in metaverse counseling. To investigate the relationships between types of client laughter and session outcomes in metaverse counseling, we employed a multilevel analysis by separating the variables into two levels: session-level (between-sessions) and client-level (between-clients). The dataset included 159 sessions nested among 26 clients. This study found that clients’ cheerful and nervous laughter positively impacted session outcomes at the session level (within individual clients). However, when considering client-level laughter events (between-client), nervous laughter at the session level was not significantly related to session outcomes. Polite, reflective, and contemptuous laughter showed no significant relationship with the session outcomes. None of the laughter events were related to session outcomes at the client level (between clients). However, there was a significant within-level interaction effect between session and cheerful laughter on session outcomes. The implications of the effects of client laughter are discussed in metaverse counseling by comparing them with those of in-person counseling.
... So gesehen kann Humor auch unter ernsthafter Betrachtung als "gesund" gelten [13]. Relevant im hiesigen Kontext sind Wirkmechanismen wie der Einfluss auf die Kortisol-Response unter Stress [1,25], mentale Entlastung [28], die allgemeine Stärkung der Resilienz [26,28,40], die Stärkung des Zusammengehörigkeitsgefühls [39] und die Förderung einer Verarbeitung traumatischer Erlebnisse [26,28]. ...
Humor has been shown to have protective effects against the increased risk of posttraumatic stress symptomatology in emergency professionals. However, the acceptance of humor in the context of emergency medicine is controversial. The aim of this study is to investigate how often and in what context humor is used by emergency workers and physicians, and what subjective helpfulness is attributed to it.
A survey was conducted in Germany with n = 160 physicians and n = 100 employees from rescue professions. The survey assessed subjective emotional stress and secondary traumatization using PTSS-10. Additionally, a questionnaire was administered to evaluate the use and subjective meaning of humor.
The majority of participants found humor to be helpful and attributed high importance to it. Notably, it was found that “black humor” was widely accepted, and together with coping humor, it was significantly more preferred than telling jokes. Making “Jokes” about children and the deceased were considered inappropriate. Approximately 80% of the sample agrees that there is a unique sense of humor shared only among medical professionals. More than 25% of the sample exhibits secondary traumatization, which correlates with occupational and private stress as well as acceptance of black humor.
In emergency professions, humor is often considered to be resilience-strengthening, including black humor. Guidelines for dealing with humor in supervision and training contexts are limited. The potential effects of humor include a reduction in assignment anxiety and an improvement in group cohesion. Despite this, the topic of humor in rescue professions has received little attention in medical ethics.
... Laughter also contributes to psychosocial and physical health aspects and several studies [10,11,12,13,14,15] have shown that it can effectively alleviate negative emotions such as anxiety and depression. Physiologically, laughter reduces stress hormones [6, 14] and increases T lymphocytes by activating natural killer cells, which causes an upsurge in white blood cells and immunoglobulin (Ig) levels, thus increasing a body's immunity [15,16,17]. ...
... Laughter also contributes to psychosocial and physical health aspects and several studies [10,11,12,13,14,15] have shown that it can effectively alleviate negative emotions such as anxiety and depression. Physiologically, laughter reduces stress hormones [6, 14] and increases T lymphocytes by activating natural killer cells, which causes an upsurge in white blood cells and immunoglobulin (Ig) levels, thus increasing a body's immunity [15,16,17]. Laughter also lowers blood pressure: it reduces vasoconstriction through a decrease in the breakdown of nitric oxide, a vasorelaxant substance, and raises blood glucose levels by reducing cortisol [14,18,19]. ...
Background
Disorders associated with mental health significantly impact disability-adjusted life year values and represent a social problem in stressed societies. Worsening mental health also affects cognitive functions and quality of life. To address these issues, increasing attention is attracted to preventive measures vis-à-vis mental and brain health in daily life. Therefore, growing interest in care using laughter has recently been noted. This study was designed to assess the effects of a short-term laughter-based intervention on the mental health and cognitive functions of middle-aged and older adults.
Methods
The study applied a single-blind, crossover-controlled trial design. Cognitive tasks were performed after participants viewed a video clip of approximately four minutes (humor or control video) and the resulting scores were treated as the primary endpoint. Secondary endpoints included cerebral blood flow in the dorsolateral prefrontal cortex, heart rate variability, subjective mood state assessment, and salivary stress biomarkers.
Results
The study was conducted on 25 healthy Japanese-speaking adults aged 40 to 65 years. Results revealed a significant increase in digit vigilance scores and in comparison to viewing the control video, participants evinced a trend toward an increase in serial 7 subtraction scores after viewing the humor video. No significant differences were found in scores on other cognitive tasks. The cerebral blood flow was also significantly higher in the dorsolateral prefrontal cortex during cognitive tasks performed after participants viewed the humor video compared to the control video. The outcomes of heart rate variability, subjective mood state assessment, and salivary stress markers also suggested that the humor video intervention could subsequently contribute to the activation of parasympathetic activity and reduce psychological stress levels induced by the cognitive tasks.
Conclusions
The study outcomes indicated that interventions using short humor videos can improve attention focus and may help to reduce psychological stress levels. These results support the clinical benefits of humor, which could be utilized as a simple and non-invasive approach to promoting the health of middle-aged and older adults.
Trial registration
The study was registered at the University Hospital Medical Information Network (UMIN) database (Registration No. UMIN000043332||http://www.umin.ac.jp/ctr/) on 15/02/2021.
... In manchen Studien wurden daher mehrere Filme zur Auswahl gestellt, damit die Versuchsperson den wählen konnte, welcher dem eigenen Geschmack entspricht. Dennoch muss auch dann die Humorreaktion der Versuchspersonen auf das Material in objektiver Weise gemessen werden (Bennett & Lengacher, 2009;Pérez-Aranda et al., 2019). So muss bei der Wahl von Stimulusmaterial für eine Humorstudie Sorge getragen werden, dass bei den Versuchspersonen tatsächlich jene Emotionen durch das Material ausgelöst werden, die auch intendiert waren. ...
... Humor hat vielfältige Auswirkungen auf Wahrnehmungen, Einstellungen, Bewertungen und Emotionen, die sich direkt oder indirekt positiv auf die physische und psychische Gesundheit auswirken können. Studien haben Humor und Lachen mit verschiedenen physiologischen, psychologischen, soziologischen und verhaltensbezogenen Vorteilen in Verbindung gebracht (Bennett & Lengacher, 2009;Claxton-Oldfield & Bhatt, 2017;Fry, 2013;Martin, 2001;Mora-Ripoll, 2010). Direkte präventive Wirkungen sind der Schutz vor Krankheiten durch Stressabbau (Berk et al., 1989), Verbesserungen der Gefäßfunktionen (Sugawara et al., 2010;Tan et al., 2007) und eine Steigerung der Funktion des Immunsystems (Bennett & Lengacher, 2009;Lefcourt, 2005). ...
... Studien haben Humor und Lachen mit verschiedenen physiologischen, psychologischen, soziologischen und verhaltensbezogenen Vorteilen in Verbindung gebracht (Bennett & Lengacher, 2009;Claxton-Oldfield & Bhatt, 2017;Fry, 2013;Martin, 2001;Mora-Ripoll, 2010). Direkte präventive Wirkungen sind der Schutz vor Krankheiten durch Stressabbau (Berk et al., 1989), Verbesserungen der Gefäßfunktionen (Sugawara et al., 2010;Tan et al., 2007) und eine Steigerung der Funktion des Immunsystems (Bennett & Lengacher, 2009;Lefcourt, 2005). Weitere Forschungen haben ergeben, dass Humor die Schmerztoleranz erhöht (Alcantara et al., 2016;Felluga et al., 2016;Weisenberg et al., 1995) und dass die physiologischen Veränderungen durch Humor insgesamt denen durch körperliche Aktivität ähnlich sind (Bains et al., 2015;Mora-Ripoll, 2010;Sugawara et al., 2010). ...
... Humour has been purported to contribute to psychological well-being in many different ways [1]. Positive emotions such as mirth, happiness, and joy are part of the experience of humour and laughter, and are linked to lower levels of neurotransmitters and hormones involved in the stress response [2][3][4]. Using humour to change one's perspective in stressful situations can help alleviate stress and anxiety, and doing so habitually may be an effective coping strategy [5][6][7][8]. ...
Research has found that humour styles can moderate the relationship between various facets of mental health and well-being. Most of these studies have used college student samples, however, and the generalizability of these findings has not been firmly established. This study examined how humour styles moderate the relationship between hopelessness and suicide ideation in both student and community samples. Community participants from the U.S. and Canada (n = 554) and student participants from a Canadian university (n = 208) completed several self-report measures including the Humor Styles Questionnaire. Analyses revealed differences in humour styles between the samples, as well as differences in humour styles between men and women. Regression analyses showed that self-defeating humour moderated the relationship between hopelessness and suicide ideation for student participants but not for community participants. Conversely, self-enhancing humour moderated the relationship between hopelessness and suicide ideation for community participants but not for student participants. These results suggest that high levels of self-defeating humour and self-enhancing humour may be uniquely maladaptive for these respective samples. These and other findings point to the necessity of recruiting diverse samples to better understand the beneficial and detrimental associations between humour styles and mental health. The potential to use measures of humour style as a tool to help identify at-risk individuals and to inform the development of intervention programs is discussed.
... 27 Laughing promotes the production of endorphins, which raise immunity by activating natural killer cells. 43,44 In the study of Sakai et al 45 which examined the effects of laughter yoga in cancer patients undergoing surgery or chemotherapy, a conclusion was reached that laughter exercises can significantly improve the immune function of patients. This suggests that laughter yoga is effective in improving the exercise capacity of patients. ...
Background
Lung cancer is the malignant tumor with the highest morbidity and mortality rate in China. Although chemotherapy is effective in improving clinical symptoms, it causes a variety of acute and chronic side effects, seriously aggravating the psychological stress of patients. Laughter Yoga as a new type of aerobic exercise can effectively reduce stress levels and increase positive mood in patients. This study aimed to examine the effects of laughter yoga on perceived stress, positive psychological capital, and exercise capacity in lung cancer patients.
Methods
This study was a randomized, single-blind, parallel-group trial. The study enrolled 84 lung cancer chemotherapy patients from a general hospital in central China. These patients were randomly allocated to control and intervention groups (n = 42 per group) after baseline assessments. Patients in the control group received routine care and those in the intervention group received laughter yoga intervention. Perceived stress, positive psychological capital, and exercise capacity were assessed at baseline, immediately post-intervention.
Results
During the implementation of the study, there were 2 dropouts in each of the intervention and control groups. Ultimately, 80 patients in the control and intervention groups completed the trial. Patients who received laughter yoga intervention had significantly higher scores in positive psychological capital (P < .01, Cohen’s d = 0.692) and exercise capacity (P < .01, Cohen’s d = 0.659). Discernible differences were also observed in perceived stress (P < .01, Cohen’s d = 1.087) between the 2 groups.
Conclusions
The results of this study suggest that laughter yoga is an effective way and may produce beneficial effects on perceived stress, positive psychological capital and exercise capacity.
... Humor is employed both as a cognitive and behavioral strategy to deal with stress. While humor physiologically decreases the level of pro-stress factors, it improves mood-elevating anti-stress factors, thereby resulting in a reduction of stress responses (Bennett & Lengacher, 2009). In a recent study (Fritz et al., 2017), humor was found to have stress-buffering effects and a negative relationship with stress in a sample of patients with diagnosed fibromyalgia syndrome. ...
Despite increasing interest in the relationship between humor and psychological distress, investigations have failed to focus on specific categories of humor and negative mental conditions. A sample of 686 Italian participants (187 men and 499 women), aged between 20 and 76 years, completed an online survey, data from which was used to investigate the relationship between eight comic styles, depression, anxiety, and stress. Findings from the multiple linear regression demonstrate benign humor as a protective factor of all three variables considered, while irony was positively associated with anxiety and stress. Wit was a protective factor associated with anxiety, while sarcasm was positively related to depression. No significant correlations emerged between the other variables considered. These findings highlight how specific categories are linked to varying dimensions of emotional distress, which are discussed with reference to the extant literature.