DOES LAUGHTER MAKE YOU SMARTER? BENEFITS OF HUMOR FOR MENTAL HEALTH
Medically Reviewed by Dr. Rosmy Barrios - October 7, 2024
In light of evidence from the last several decades, it may be true that our sense of humor is not taken as seriously as it should be. Humor and laughter are both a product of our social evolution as a species. Moreover, they both have been shown to contribute significantly towards our overall intelligence, mental health and well-being.
The below article explores humor and laughter concerning their effects on cognition and health. In addition, the biology of humor, humor styles, the danger of using humor and tips for increasing humor in one’s life are also discussed.
Why Do We Laugh? The Biology of Humor and Laughter
While humor and laughter have both been studied as subsets of positive human emotion, they are still not very well understood. The origins of laughter have been traced back to both tickling and play in primate species.[1] It is speculated that complex humor evolved alongside language in early human history.
It is currently theorized that laughter emerged biologically for the following reasons:
- Situational Reappraisal. Laughter evolved from play and tickling. Tickling is theorized to be a tool for reappraisal as it simulates a threatening situation in a safe context, thus producing laughter. Children often play games with similar elements that create laughter. This type of play helps to release stress, bond, and recontextualize (and reconsolidate) potentially stressful events that may have occurred, such as the memory of a physical fight between siblings. In the same way, having a sense of humor about any given situation or concept typically tends to change one’s perception of it, serving to recontextualize it in a more positive manner. This can help to expand one’s ability to think and perceive the situation or concept, as is highlighted by the cognition-enhancing effects of laughter.
- Emotional Control. Lightening the mood with humor can be a potent coping mechanism for stress. Humor is used to recontextualize stressful events and memories by producing laughter, and changing the mood associated with an idea or situation. This can prevent stress or other negative emotions from taking hold as much, some of which may pose damaging consequences to health if experienced on a long-term basis.
- Social Bonding. Laughter’s natural place amongst conversations reflects how it has evolved alongside language as an integrated part of socialization. Humor and laughter promote the release of feel-good hormones such as endorphins and oxytocin[2] [3], also known as the social bonding (“trust”) hormone. This underscores how we naturally use it to ease tension in social situations and facilitate bonding.
Why Am I Even Laughing? The Components of Humor
There are three main components involved in detecting and appreciating humor:
- The Resolution of Incongruency. Humorous events, jokes or ideas are often defined as a mild form of cognitive dissonance, meaning that they consist of contradictory information or perceived incongruencies.[4] As the brain grapples with the slight conflict, the resolution of the incongruencies typically produces laughter. This can be seen in most jokes, wherein the punchline often reveals an unexpected twist or surprising turn (incongruency) that the context of the joke sets up and emphasizes.
- Intentionality. In one study, the jokes of top comedians (relative to their respective audiences) were analyzed to identify common elements that contributed to their success. It was revealed that jokes demand a certain level of complexity in order to be humorous, often conveying between 3 to 5 levels of intentionality. This refers to the communicated intentions of variables or people in the joke, which the comedian may directly or indirectly convey. The intentions are often subconsciously processed and form part of the incongruencies that make a joke funny. It was ascertained from the study that the average brain could process up to 5 different points of intentionality before a joke becomes overly complex and unamusing to an audience.[5]
- Cognitive Ability. The above finding highlights that it takes a certain level of cognition to interpret and appreciate various forms of humor. In other words, a basic level of human intelligence is necessary for finding humor in situations and ideas. This may explain the link between aging, depression, other mental disorders, and the loss of humor in some individuals, where cognitive ability is often negatively affected. As humor is known to boost certain aspects of cognition, and can be an effective therapy for related mental disorders (see below), it may be possible to practice and develop a sense of humor just like any other skill set. In this sense, humor begets more humor.
6 Benefits of Humor for Cognition and Mental Health
As previously explained, humor resulting in laughter improves mood and is a potent tool for emotional cognitive reappraisal of situations and concepts.
Positive and negative emotions have differing effects on resultant cognition, with the negatives often reducing our ability to think and reason effectively. Positive emotion may be just as overwhelming to our rational sensibilities, yet it has generally been proven to enhance overall cognition by enhancing brain connectivity and lowering stress levels.
1. Memory
Both the emotional and cognitive aspects of humor and laughter have been shown to improve our ability to remember.
Positive Emotional Memory Enhancement. The best remembered memories we have are the ones that elicit the strongest emotion, whether positive or negative.[6] This is evident in conditions such as PTSD, in which fearful memories keep on replaying in the individual. As seen with negative effects, positive memories are also well-remembered. In case of humor, it has long been observed that humorous information is better remembered than non-humorous information[7]. While negative emotions can enhance memory and are often linked with heightened stress levels, excessive stress can often result in reduced memory recall.
Memory Contextualization. Humor has been shown to improve memory recall pertaining to negative memories through reducing negative feelings[8]. It may also improve memory recall of difficult situations that would have otherwise been too stressful to remember. This becomes possible if humor formed part of the memory at the time or was used shortly after to reappraise the memory.
Sleep. In a small trial, laughter was shown to improve symptoms of insomnia and quality of sleep in elderly individuals[9] and those with depression[10]. It may enhance sleep in those prone to anxiety as well by lowering stress levels. Memory and cognitive performance are directly correlated with the quality of sleep. Sleep is a vital component of memory consolidation and serves to facilitate optimal cognition by ridding the brain of the bulk of its waste products. This is why after a good night’s sleep, we wake up feeling refreshed and ready to start the day.
Short-Term Memory. Humor is known to promote improved connectivity between brain areas that are also involved in maintaining short-term memory. Humor and laughter have been linked with better short-term memory function across studies[11], as well as in patients with neurologic and metabolic diseases[12].
2. Mood, Executive Control and Focus
Our mood is linked to our ability to focus and think coherently. Humor and laughter are great tools for exerting emotional regulation and control, thereby improving cognition. This is highlighted in the following points:
Mood and Neurotransmission. A good stable mood indicative of balanced neurotransmission is optimal for focus, executive control, and cognition. Laughter is known to release endorphins (feel-good chemicals) and elicit (or be preceded by) a positive mood. In trials evaluating laughter therapy for depression, laughter has been shown to increase both dopamine and serotonin levels, as well as help preserve stable dopamine activity in the brain.[13]
Social Reward and Motivated Cognition. In presentations, talks, and classroom settings, humor has been shown to foster a more socially supportive environment conducive to learning as well as improve attention towards the subject matter.[14] [15] Pleasant social activity and humor are both known to be rewarding[16], and able to enhance cognition through increasing social motivation. This can be explained by the way in which reward enhances goal-oriented focus and behavior. In the context of socialization, this typically improves mood, attention, and cognition pertaining to the conversation and participants.[17]
Reappraisal and Stress Resilience. While it has always been known, studies in the last decade have proven that humor is one of the best strategies for coping emotionally with stressful situations. In one such trial, 57 participants were shown negative images and were then asked to rate their emotional responses. The group that used humor as a coping strategy scored the best in terms of emotional regulation, having a greater increase in positive emotions after reappraising the situation from a humorous perspective. This group scored better than a second experimental group that used a serious cognitive reappraisal strategy, recontextualizing the images in the absence of humor. In this way, humor can improve emotional resilience towards stressful stimuli.[18]
Enhanced Emotional Control. Humor has been shown to increase connectivity between areas of the brain involved in processing logic and emotions.[19] Under usual circumstances, these serve contradictory functions, which is highlighted by how emotions can overshadow rational thinking and vice versa. Humor processing can therefore strengthen rational thinking in emotional situations and improve emotional control.[1]
May Favorably Strengthen Personality. Brain areas involved in personality development have been shown to play a role in emotional processing as well as humor appreciation[20]. As less resilient personalities are often more prone to stress or negative emotion, humor may be able to encourage resilience and better emotional control during stressful circumstances.
Emotional Distraction. Naturally, humor can serve to distract one’s focus from factors that may promote stress or negative affect[21]. Stress and negative emotion are both associated with diminished executive control and focus.
3. Neurogenesis
Humor and laughter can enhance emotional and executive control, which influences behavior, reaction times and more. This also alludes to its ability to promote enhanced brain growth.
Stress Reductions. Neurogenesis shares a bidirectional relationship with one’s stress levels, as reflected by the levels of neuronal growth factors. Naturally, laughter can reduce stress levels[22], which can increase the levels of BDNF (brain-derived neurotrophic factor) in the brain, and hence may enhance neurogenesis.
Immune Function. Proper functioning of the immune system in the nervous system is a crucial aspect of cognition, memory consolidation, neuroplasticity, and neurogenesis[23]. In a study conducted on 52 healthy men, mirthful laughter was shown to improve neurologic immune markers. The findings included heightened levels of antibodies, lymphocytes, and helper T cells (vs suppressor cells). Many other immune cells showed functional enhancements, including granulocytes, natural killer cells, B cells and T cell subtypes. Interferon gamma levels were shown to improve as well. Most of these observations were documented to last up to 12 hours post-laughter.[24] Other studies also concur with these observations, proving how laughter is able to lower inflammation[25]. Together, this highlights how laughter supports cognition and neurogenesis by enhancing immune function.
Improved Brain Connectivity in Humor-Related Areas. As with any other skill, engaging with our sense of humor may promote enhanced development and renewal in brain areas pertaining to humor processing and emotional regulation.
May Boost BDNF in those with Schizophrenia and Neurological Conditions. The sound of laughter has been shown to increase BDNF in patients with schizophrenia over the course of 8 weeks.[26] Schizophrenia is neurologically characterized by destruction of brain tissue due to an unknown cause. Therefore, laughter therapy may be complementary to the treatment of schizophrenia for promoting better cognition and possibly neurogenesis.
4. Neuroplasticity
Both the creation and appreciation of humor can influence neuroplasticity positively in a number of ways:
Creativity and Flexibility of Thought. Humor shares major overlaps with creative cognition[27], in which multiple brain areas are commanded in order to produce a novel or unexpected “creative” outcome – in this case, with humorous effect. Genetic studies have confirmed that creative processing in the brain is linked to enhanced neuroplasticity and flexibility of thought[28]. Therefore, having a sense of humor and putting it to good use is conducive to promoting brain neuroplasticity, thereby enhancing overall cognition.
Humor Promotes Brain Connectivity and Restructuring. As explained above, humor cognition promotes structural brain changes that are associated with reappraisal of a situation or concept. Furthermore, positive emotion induced via laughter has been shown to increase connectivity between the thalamus and frontal cortex, in order to facilitate mental restructuring and reappraisal.[29] In accordance with these findings, the more one practices or indulges in humor, the more flexible one can be in shifting one’s perspective, which can lead to adaptive thinking and new ideas.
5. Cardiovascular Health Benefits of Humor and Overall Cognition
The benefits of physical activity on cognition have partially been attributed to cardiorespiratory fitness and one’s state of cardiovascular health. Recent studies show how humor improves aspects of cardiovascular health similarly to exercise, albeit not to the same degree!
A few of the potential cardiovascular benefits of humor and laughter are discussed below in relation to mental well-being:
May Improve Cardiovascular Disease Outcomes. Laughing on a daily basis is associated with a reduced risk of cardiovascular disease[30], lower cardiovascular mortality and improved chances of recovering from a cardiovascular condition.
Laughter is Comparable to Exercising. Intensive laughter has been shown to emulate a similar cardio-protective benefit of exercise by increasing the heart rate, lowering its variability[31], relaxing the muscles, improving blood flow, and enhancing blood oxygenation[32]. Reduced heart rate variability is associated with lower stress levels and has been proven to encourage optimal overall cognition in a study conducted on over 19000 participants[33].
Laughing May Improve Vascular Tone, Memory, and Learning. Preliminary evidence suggests that laughter may improve vascular tone. This is suggested to be the case as laughter is known to promote relaxation of the nervous system, better cardiovascular outcomes, and the release of beta-endorphins. Laughter-induced beta-endorphins have been shown to activate specific opioid receptors that are associated with the production of nitric oxide, as well as good mood and better overall cardiovascular health.[34] Nitric oxide is known to relax the blood vessels, enhance vascular tone, and therefore, improve brain and body circulation. Additionally, nitric oxide is known to act as a neurotransmitter in the brain that is capable of enhancing both memory and learning processes. [35] [36]
6. Humor Maintains Mental Well-Being for Life
Several long-term studies have highlighted that maintaining humor for life has lifelong effects on mental well-being, quality of life and overall health.
Humor May Protect Against All-Cause Mortality. During the course of a 15-year follow-up trial in which over 50,000 participants were surveyed, humor was shown to be associated with a reduced risk for all-cause mortality up until 85 years of age[37]. These effects were attributed to the cognition-enhancing effects of humor, and not to the emotional or social effects. Therefore, not only does humor improve our quality of life, it may also prolong the consequences of age-related diseases, including dementia.
4 Other Benefits of Humor and Laughter
Cognitive benefits aside, humor and laughter may enhance well-being in the four following ways:
Pain Relief. Several trials over the years have confirmed that laughter makes us feel good, not just emotionally but physically as well. Laughter can enhance our tolerance towards pain and promote the release of endorphins which serve as painkillers.
Potentially Regulates Blood Sugar Levels. Laughter served to reduce elevations in blood sugar in diabetic individuals 2hrs after consuming a meal.[38] This effect is similar to that of adequate physical activity; however, the underlying mechanism was proven to be unique and, therefore, complementary to exercise in terms of controlling blood sugar levels.
Recovery and Rehabilitation. Humor and laughter have both been shown to improve recovery and rehabilitation outcomes post-surgery, particularly pertaining to heart surgery.[39] Due to the positive immune benefits of laughter and the recontextualizing powers of humor, it is hardly surprising that patients did better with the inclusion of both during recovery.
Promoting a Healthy Social Life. Humor is a prominent feature of positive social interactions, bonding, and long-lasting relationships. It can therefore be viewed as foundational to establishing a healthy social life. Maintaining close social relations throughout one’s life is generally associated with longevity and better health[40]. In one study, it was found that women who socialize frequently live up to 10% longer on average and are 41% more likely to make it to the age of 85[41].
Different Types of Humor and Their Mental Effects
Humor differs in accordance with one’s age, social context, personality, and exposure.
Benign vs Detrimental Humor
Benign humor is a more positive type of humor that is not derived at the expense of others, whereas detrimental humor is the opposite. Dark or black humor, while potentially highlighting someone’s misfortune, can be either benign or detrimental.
Benign Humor is Better for Emotional Regulation. Benign humor was shown to improve cognition and reappraisal of negative emotional stimuli or situations better than dark (detrimental) humor.[42] Benign humor has also been associated with a larger degree of brain activity, as opposed to detrimental humor[43]. This suggests that benign humor is healthier and better for improving cognition than detrimental humor.
The Intention Behind the Joke Counts. Humor typically loses its impact the less benign it is, with the intention having the greatest impact on the emotions and mental health of the viewer. This has been documented in recovery scenarios, where humor applied in an effort to control a conversation or to socially distance a person, were both associated with negative perceptions of social and psychological health. A positive sense of humor that emphasized health and recovery appeared to boost the perceived social and psychological well-being of patients.[44] These findings highlight that humor is a powerful tool for appraisal and contextualization, which outwardly affects health and wellness outcomes across people.
Other Possible Benefits of Benign Humor include:
- Improved Conflict Resolution. Studies reveal that creative cognition can effectively promote conflict resolution by changing negative conflict-related thought processes[45]. As humor overlaps with creative cognition and is a fantastic tool for positive reappraisal of situations, it is likely that humorous thinking may be the most effective form of creative cognition for reducing conflict at the mental and emotional levels.
Humor Styles, Brain Regions, and Personality Differences
Four main humor styles have been identified in the literature that are associated with various mental health effects:
- Affiliative humor typically supports harmonious social interactions by enforcing positive assertions about others and has been linked with a higher level of conscientiousness.
- Self-defeating humor positively enhances socialization by indirectly bolstering the image of others at one’s own expense. It can be psychologically limiting for the one purporting it. Associated with lower levels of conscientiousness and increased neuroticism, it is generally linked with higher levels of openness among individuals.
- Self-enhancing humor is usually a benign form of humor that serves to humorously bolster one’s self image. It has been shown to maintain mental health and has been linked with reduced neuroticism. However, it can detract from group socializing.
- Aggressive humor is generally detrimental, offensive, and used to indirectly bolster self-image at the expense of others. It has been associated with a higher frequency of negative social interactions, low conscientiousness, increased neuroticism, reduced agreeableness, and less openness in comparison to other humor styles.
Further investigation confirms that changes in white brain matter and neural connectivity can influence one’s preferred humor style, as well as activity in various brain areas.[46] These findings may suggest that various forms of humor are able to enhance white matter integrity and connectivity in parts of the brain pertaining to emotional regulation, personality, empathy, and self-reflexivity.
Humor Type and Depression. In depressed individuals, the use of aggressive and self-defeating humor styles were associated with promoting depressive symptoms. Self-enhancing and affiliative humor proved to be beneficial for counteracting depressive thinking and improving mood, in some but not all studies.[47]
Other Types of Humor
Dark Humor: may be more cognitively demanding. Benign forms of dark humor may elicit laughter in those able to appreciate it, without lending itself as a tool for reappraisal of dark situations. Despite this, dark humor appreciation has been linked to higher educational status and intelligence, and is believed to be related to a person’s ability to treat dark humor as a form of playful fiction. It is theorized that this requires a higher level of cognition to achieve.[48]
Nonsense humor: refers to an absurd situation or idea in which there is partial or no resolution towards perceived incongruency. By contrast to conventional types, nonsense humor is known to increase activity in regions associated with word processing and language.[49] It also requires less activation of ordinary humor-related brain regions, including less self-referential processing[50], suggesting that it may be easier to comprehend and less mentally stimulating than conventional humor forms.
Slapstick Humor refers to situational non-verbal comedy and is one of the earliest forms of humor. As with nonsense humor, it is more simple than verbal humor, and often able to reach a larger audience as a result.
How Do the Cognitive Benefits of Humor Compare Against Other Healthy Lifestyle Habits?
The cognitive-enhancing[2] effects of humor and laughter are comparable to physical exercise and creative activities, yet not as pronounced. However, humor and laughter rank far higher than any of these activities in terms of improving mood and emotional reappraisal of stressful situations. These features of humor and laughter make them indispensable for our quality of life at every step.
Laughter and Exercise. Laughter in particular has been shown to lengthen lifespan in a way similar to that of physical exercise. However, it has also been shown to modulate immune function in a different way than exercise, suggesting that both are complementary activities that serve to enhance overall vitality.
Humor and Creative Cognition. Despite sharing neuro-biological commonality, humor is not able to influence our creative abilities in the same way as a physical creative hobby would. Humor lacks physical and spatial components that contribute more towards brain development. However, developing a sense of humor may enhance one’s ability to think creatively and, therefore, may contribute towards the development of creative skill sets.
When Laughter is a Bad Thing
Humor and laughter can be problematic in the contexts of propaganda, damaging divisive thinking, and disease.
Superiority Encouragement. Historically, laughter has been scorned for upholding ideals of superiority by some of the world’s greatest philosophers, including Plato and Aristotle.[51] Unfortunately, there may be truth to these sentiments. Superiority, inferiority and similarity to others can form enough of a contrast that acts as a medium for humor (i.e. an incongruence to be resolved). As humor and laughter are potent tools for reappraisal and recontextualization of situations and concepts, including one’s personality and self-image, developing this type of humor may be dangerous, as it can serve to enforce superiority, delusions of grandeur and violent thinking, and eventually, violent behavior. Just as humor can be used detrimentally, it can also be used to discourage this type of divisive thinking (see dark vs benign humor above).
Pathological Laughter. Laughter in the absence of humor and/or self-control is typically deemed pathological.[52] This form of laughter has been associated with rare types of strokes and seizures, various mental disorders, including schizophrenia, mania, mood disorders, dementia, and various forms of mental retardation. [53] Laughter in these situations may be viewed as a physiological coping mechanism in response to the disease, a neurochemical imbalance and/or a manifestation of brain damage that triggers laughter.
5 Tips for Encouraging More Humor in One’s Life
While humor can be an effective tool in promoting cognition, a dull mind is also known to limit humor appreciation and laughter.[54] Thus, enhancing mood and cognitive abilities improves one’s ability to identify mirth in their life.
The following suggestions may help to encourage more opportunities to appreciate humor:
- Living Healthily. Adequate physical exercise and consuming a healthy balanced diet can easily promote better health overall, which includes improved cognition and mood. These principles, in conjunction with getting good quality sleep and sun exposure, are fundamental to well-being and a positive mindset.
- Self-Reflection and Positive Self Image. A positive self image can be conducive for appreciating more benign and beneficial forms of humor that are known to enhance cognition better than detrimental humor styles. Self reflection can be used as a tool for boosting one’s self image. It also tends to provide many opportunities to practice one’s sense of humor in a way that can help to positively shape one’s personality, increase emotional control and offer mental resilience.
- Watching Comedy is a great way to engage with humor and promote more laughter. Over time, it can expand one’s sense of humor as well and provide more opportunities for laughter during social interactions.
- Social Connection. Humor is largely a social invention that strengthens social ties and connections. Investing time in healthy social relations can provide chances to engage with humor as well as positively influence one’s humor style.
- Creative Hobbies. By taking up creative hobbies, one can increase their inherent creativity and promote brain activity that can indirectly enhance their sense of humor. Creative endeavors are also rewarding and tend to uplift one’s mood, which can promote humorous ideas as well.
Conclusion
Despite humor’s non-serious connotations, evidence suggests that it holds a serious place in the context of human health and wellbeing. Humor and laughter promote mental stability, emotional control, and optimal cognition, indicative of a positive and resilient personality. The physiological impact of laughter almost matches up to the likes of physical activity, and has been shown to be complementary. Those with a sense of humor tend to laugh more often and live longer, more fulfilling lives than those who lack humor or do not laugh as much. Humor can be cultivated through comedy and social interactions, and enhanced through self-development, the pursuit of creative hobbies and leading a healthy lifestyle.
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