Kurzgesagt – In a Nutshell
Sources – Friendship / How to make friends
We thank the following experts for their help with this script:
Prof. Jeffrey A. Hall
Department of Communication Studies, University of Kansas
Prof. Robin Dunbar
Department of Experimental Psychology, University of Oxford
Lydia Denworth
Contributing Editor, Scientific American
Almost nothing predicts how happy you will be as how connected you feel and a lack of social connection is associated with a number of diseases and a shorter life.
Loneliness can shorten life. The following review found an increased likelihood of up to 32% (depending on the specific situation).
#Holt-Lunstad, J. et al. (2015): Loneliness and Social Isolation as Risk Factors for Mortality: A Meta-Analytic Review. Perspectives on Psychological Science 2015, Vol. 10(2), pp. 227–237
https://pubmed.ncbi.nlm.nih.gov/25910392/
Quote: “Social isolation results in higher likelihood of mortality, whether measured objectively or subjectively. Cumulative data from 70 independent prospective studies, with 3,407,134 participants followed for an average of 7 years, revealed a significant effect of social isolation, loneliness, and living alone on odds of mortality. After accounting for multiple covariates, the increased likelihood of death was 26% for reported loneliness, 29% for social isolation, and 32% for living alone. These data indicated essentially no difference between objective and subjective measures of social isolation when predicting mortality.”
More specifically and as an example, loneliness can increase the risk of heart disease (e.g., stroke) by a similar order of magnitude (around 30%).
#Valtorta, N. K. et al. (2016): Loneliness and social isolation as risk factors for coronary heart disease and stroke: systematic review and meta-analysis of longitudinal observational studies. Heart Vol. 102, pp. 1009–1016
https://heart.bmj.com/content/102/13/1009
Quote: “Results Of the 35 925 records retrieved, 23 papers met inclusion criteria for the narrative review. They reported data from 16 longitudinal datasets, for a total of 4628 CHD and 3002 stroke events recorded over follow-up periods ranging from 3 to 21 years. Reports of 11 CHD studies and 8 stroke studies provided data suitable for meta-analysis. Poor social relationships were associated with a 29% increase in risk of incident CHD (pooled relative risk: 1.29, 95% CI 1.04 to 1.59) and a 32% increase in risk of stroke (pooled relative risk: 1.32, 95% CI 1.04 to 1.68). Subgroup analyses did not identify any differences by gender. Conclusions Our findings suggest that deficiencies in social relationships are associated with an increased risk of developing CHD and stroke. Future studies are needed to investigate whether interventions targeting loneliness and social isolation can help to prevent two of the leading causes of death and disability in high-income countries.
Surprisingly nowadays loneliness is highest among young people – whose relationships were also hit especially hard by the global pandemic.
Although it is difficult to make general statements, since "loneliness" also depends on cultural background and specific age, there are some studies that indicate that the problem is more prevalent among younger people. The following source is an example.
#Achterbergh, L. et al. (2020): The experience of loneliness among young people with depression: a qualitative meta-synthesis of the literature. BMC Psychiatry Vol. 20 (415)
https://bmcpsychiatry.biomedcentral.com/articles/10.1186/s12888-020-02818-3#citeas
Quote: “Extrapolating the findings of studies in older age groups to younger people is problematic given that experiences of loneliness vary in different demographic and cultural groups. The social context of loneliness is also very different in young people to later stages of life. Additionally, the experience of depression is also likely to vary by age, with symptoms of irritability and interpersonal difficulties being particularly prominent among adolescents.”
The 2018-19 Community Life Survey from England shows that 16% of all 16 to 34 year olds often/always feel lonely, compared to 11% of people 65 and older.
The difference seems small, but when you look at the fact that 27% of 16 to 34 year olds never feel lonely and 61% of those over 65, it's easier to see that younger people tend to be more affected by loneliness.
#Department for Digital, Culture, Media & Sport (2019): Community Life Survey 2018-19
If you suffer from chronic loneliness you can also watch the video we made about it.
#Kurzgesagt - In a Nutshell (2019): Loneliness
https://www.youtube.com/watch?v=n3Xv_g3g-mA
People make friends with other people when they spend casual time together.
A study that followed college students for 18 months and examined their relationships with friends and relatives (“kin relations”) found that friendships are more sensitive to less contact or shared activities than kinships.
Even though the study primarily focused on the difference between friendships and kinships, you can see how important proximity and shared spare time are for friendships.
#Roberts, S. & Dunbar, R. (2011): The costs of family and friends: an 18-month longitudinal study of relationship maintenance and decay. Evolution and Human Behavior, Vol. 32 (3), pp. 186-197
https://www.sciencedirect.com/science/article/abs/pii/S1090513810000966?via%3Dihub
Quote: “First, the emotional intensity of friendships, as compared to kin relations, was more sensitive to decreases in contact frequency between the participant and the friend. Second, the emotional intensity of friendships, as compared to kin relations, was more sensitive to decreases in the number of activities performed together in the preceding time period. These results were not affected by including control variables such as gender of participant or network member, ethnic group or destination of participant after school in the models. Thus, when followed over the course of 18 months, kin relations and friendship showed important differences. Friendships required more maintenance — in terms of communication and performing activities together — than kin relations to sustain at particular levels of emotional intensity.”
One study found that in student dormitories, the distance between rooms was the strongest friendship predictor – living closer together meant a higher chance of becoming friends.
In very simplified terms, all 320 residents of a student dormitory were asked over several years who their roommates and friends were, and they were asked to say, on the basis of a list of names of all residents, whether they had seen this person before, knew him or her, or did not know him or her at all.
The result: The roommates liked each other the most and the more "distant" the other students were in terms of living situation (same floor, same house, tower, i.e. between different houses) the less they liked each other.
#Priest, R. F. & Sawyer, J. (1967): Proximity and Peership: Bases of Balance in Interpersonal Attraction. American Journal of Sociology, Vol. 72 (6), pp. 633-649
This also showed that within a corridor, for example, it makes a difference whether there is only one room between two people or, say, four. The closer the rooms were to each other, the more the respondents liked each other.
#Priest, R. F. & Sawyer, J. (1967): Proximity and Peership: Bases of Balance in Interpersonal Attraction. American Journal of Sociology, Vol. 72 (6), pp. 633-649
Another study showed that being physically present in a class a lot, without saying a word, makes others more sympathetic to you.
#Moreland, R. L. & Beach, S. R. (1992): Exposure Effects in the Classroom: The Development of Affinity among Students. Journal of Experimental Social Psychology Vol. 28 (3), pp. 255-276
https://www.sciencedirect.com/science/article/abs/pii/002210319290055O
Quote: “The actual results of our field experiment are summarized in Table 2. The effects of mere exposure on the various measures of familiarity, attraction, and similarity were assessed through another series of singlefactor (Number of Visits: 0/5/10/15) repeated-measures analyses of variance. (...) Mere exposure had its weakest effects on familiarity. None of the students knew any of the women. Only a few of the students (8 to 13%) remembered seeing even one of the women, and women who attended more class sessions were not significantly more likely to be remembered. All of the women were rated as unfamiliar (M < 4.00) by the students. Women who attended more class sessions were indeed rated as significantly more familiar, but this effect was very small in size (.012). These results indicated that familiarity was largely unaffected by exposure. Given the conditions under which exposure occurred, this may not seem surprising. We were surprised, however, by the relatively strong effects of mere exposure on attraction. These effects ranged in size from .056 to 603, with a mean of .273. Women who attended more class sessions earned significantly higher scores on the attraction index, and the students believed that they would be significantly more likely to befriend those women, enjoy spending time with them, and work with them on some project. (...) Finally, mere exposure also affected similarity, although these effects were weaker than those for attraction. The effects of exposure on similarity ranged in size from .023 to .122, with a mean of .077. Women who attended more class sessions earned significantly higher scores on the similarity index, and the students believed that they would be significantly more likely to share the social backgrounds of those women, understand their personalities, and have similar plans for the future.”
The average American teenager spends more time on Tik Tok every day, than socializing at parties, events or on the phone with friends combined.
According to a study of 400,000 families with children between the ages of 4 and 18 from around the world (with a focus on the US, UK and Spain), US children use TikTok for 99 minutes a day.
Between 2020 and 2021, the duration increased (from 87 to 99 minutes), which may be due to growing popularity, but may also be a result of the Corona pandemic.
#Qustodio (2022): Living and learning in a digital world. Annual Data Report 2021, p. 29
https://static.qustodio.com/public-site/uploads/ADR_2022_en_040422.pdf
While 15-17 year old Americans spend most of the day sleeping, a relevant part takes place in front of the screen (without direct reference to school, e.g. as homework) and only about one hour can be classified as socializing.
The figures are from 2014 to 2017 and may be slightly different today. A higher proportion of "screen time" can be expected, especially due to the Corona pandemic.
#Pew Research Center (2019): The way U.S. teens spend their time is changing, but differences between boys and girls persist.
The friendship paradox is the phenomenon that on average, most people have fewer friends than their friends. Which makes sense, since you are more likely to be friends with someone who has many friends, than with someone who has few.
Rather than being densely interconnected, friend networks are often built around central hubs. So if central people disappear from your life, this can deprive you of many connections at once. And it can lead to a distorted self perception: that you are less popular than others, although you are perfectly average.
It’s just a mathematical problem from the theory on networks.
#Feld, S. L. (1991): Why Your Friends Have More Friends Than You Do. American Journal of Sociology, Vol. 96 (6), pp. 1464-1477
https://www.jstor.org/stable/2781907
Quote: “The basic logic can be described simply. If there are some people with many friendship ties and others with few, those with many ties show up disproportionately in sets of friends. For example, those with 40 friends show up in each of 40 individual friendship networks and thus can make 40 people feel relatively deprived, while those with only one friend show up in only one friendship network and can make only that one person feel relatively advantaged. Thus, it is inevitable that individual friendship networks disproportionately include those with the most friends.”
Studies have shown that new friendships can develop quite quickly, weeks after you meet someone.
In one study, nearly 90 female and male freshmen were followed for several weeks and had to answer questionnaires about their relationships with two other students they had just met. The questions asked about activities but also characteristics about the relationship with each other.
As a result, the researchers were able to make statements about the development over time, intensity or quality of a friendship, among other things.
#Hays, R. B. (1985): A Longitudinal Study of Friendship Development. Journal of Personality and Social Psychology 1985, Vol. 48 (4), pp. 909-924
https://pubmed.ncbi.nlm.nih.gov/3989674/
Quote: “The period between the 3rd and 6th weeks of the dyads' acquaintance appeared to be a relationship-building phase. Not only was it the most behaviorally intensive period for the close friends, whose interaction rates increased considerably in virtually all casual and intimate behavior categories, but it also showed the greatest rise in the successfully progressing dyads' friendship intensity ratings. This stage of friendship may represent an exploratory period in which the potential friends were getting to know each other and—in social exchange terms—sampling the reward potential of the relationships before evolving to a more stable pattern of interaction. The intercorrelations among the dyads' friendship intensity scores at the various assessment times showed that by the 6th week the friendships had become relatively stable.”
But it takes a few months for a casual friendship to become a close relationship – with the biggest impediment being time invested and the quality of your interactions.
You can find an introduction to the complex topic of "friendship and time" here:
#Miritello, G. et al. (2013): Time as a limited resource: Communication strategy in mobile phone networks. Social Networks, Vol. 35 (1), pp. 89-95
https://www.sciencedirect.com/science/article/abs/pii/S037887331300004X?via%3Dihub
Quote: “Time is an inelastic resource, and people only have a limited amount of time in each day to devote to social interaction. Further, the emotional intensity of a tie is strongly related to the frequency of communication between the two individuals and frequent communication is necessary to prevent a tie from decaying in emotional intensity over time. Since communication always takes time,the limited amount oftime available for communication acts as a constraint on the number of ties that can be maintained at each level of emotional intensity.”
Following study investigates the time required to set up a friendship.
#Hall, J. A. (2018): How many hours does it take to make a friend?
https://journals.sagepub.com/doi/full/10.1177/0265407518761225
Quote: “To answer the primary question about the number of hours to make friends at different levels (RQ1), Figure 1 should be examined in conjunction with the results of the three logistic regressions. According to Figure 1, at low amounts of time (<10 hr), relationships are best described as acquaintances (51%) or friends of friends (16%). Casual friendships emerge around 30 hr, followed by friendships around 50 hr. Good friendships begin to emerge after 140 hr. Best friendships do not emerge until after 300 hr of time spent. Whether spending 30 or 600 hr of time together, the percentage of all relationships formed in closed systems (e.g., work, school) remains relatively constant. Logistic regressions offered 3-point estimates: 94 hr when acquaintances become casual friends, 164 hr when casual friends become friends, and 219 hr when friends become good/best friends. These numbers are likely conservative estimates due to the inclusion of both closed system and chosen relationships and due to the retrospective nature of the study. It is quite likely that the friendship status transitioned to a higher level before these cut-point estimates.”
Generally speaking, extroverts tend to crave sensory stimulation, spicier foods, loud music, or the excitement of engaging a crowd. Introverts, often confused with shy people, tend to be more sensitive to sensory stimulants and prefer quieter surroundings, fewer people and even less spicy food.
Put simply, this might be because certain brain activities are naturally stronger in introverts than in extroverts. Introverts are "hyper-actived" and therefore tend to engage in activities that are calming. Extroverts, on the other hand, tend to be "under-active" (or "infra-activated" as the quote describes it). They therefore need stronger stimulation (“arousal”) to achieve optimal brain activity. In the source below you will find a first entry to this topic.
#Gomes, A. C. et al. (2021): Caffeine Produces Neutral Effects on Extraverts’ and Introverts’ Performance of Fundamental Motor Skills. Journal of human kinetics, Vol. 78, pp. 229-237.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8120956/#j_hukin-2021-0038_ref_007
Quote: “Individual differences associated with extraversion reflect contrasts in the neurophysiological functioning, specifically cortical activation (arousal), which is the energy required for basic cortical processes to occur, such as perception, memory, and reasoning. Extraverts are typically sociable and talkative because they bear low levels of cortical activation. Introverts, in turn, have predispositions to be quiet and withdrawn due to their high levels of arousal. For these particular characteristics, extraverts tend to seek high-intensity stimuli, whereas introverts prefer lower intensity ones. The level of arousal is influenced by the environment and other external factors, thereby extremely high or low arousal levels may provoke discomfort. This pattern has been explained by the inverted-U principle: extraverts are infraactivated, thus they seek stimulating factors to achieve pleasant cortical activation levels, while introverts are hyper-activated and, as a result, they tend to select places or situations to reduce arousal to the optimal level. These extreme levels of arousal might lead extraverts and introverts to have different reactions to the same stimuli or situation. For example, extraverts tend to prefer speed over accuracy, while introverts are more inclined to accuracy over speed.”
Men especially form friendships around shared activities but in general it is a good idea to go to places that feel comfortable, where there are people you might like, who do things you find interesting.
The following resource provides an initial start on the topic of “friendship and sex/gender”.
It provides an overview of what evolutionary and cultural conditions may have led to different expressions of male and female friendships.
#Hall, J. (2015): Same-Sex Friendships. In: The International Encyclopedia of Interpersonal Communication.
https://www.researchgate.net/publication/314826577_Same-Sex_Friendships
Quote: “Biological and cultural processes influence characteristics of same‐sex friendships, both individually and in tandem. Biological accounts of sex difference in friendship identify and differentiate adaptive properties of friendship shared by both males and 3 females from those that may have produced differences between the sexes. Evolutionary accounts of sex difference in friendship start with the principle of individual difference in aptitudes and characteristics present in potential friends. Potential friends possess varying association values; some individuals have more useful, enjoyable, adaptive, or beneficial characteristics than others (Tooby & Cosmides, 1996). Thus, because the formation of a friendship implies reciprocity, especially in a close friendship, befriending one individual over others offers a greater association value. Inasmuch as some traits offer benefits to or serve the needs of females more than the needs of males (or vice versa), females should select, maintain, and value friends with those beneficial behaviors or qualities. From an evolutionary point of view, sex differences in friendships evolved due to differences between females and males in benefits obtained by befriending individuals with particular qualities and attributes.
(...)
Cultural accounts for sex difference point to more proximal, culturally sensitive, temporally situated, and historically contextualized explanations for sex differences. One example of this perspective is articulated in social role theory, which suggests that gender roles are produced and reinforced through social interaction. The similar value of same‐sex friends and the importance of inclusion for both males and females reinforce these within‐sex gender role proscriptions.”
And of course there are friends you’ve lost touch with. You may be able to revive some of these relationships. In some cases all it needs is a call or an invitation. Research shows that more often than not, the other person will appreciate that you’ve reached out!
The study by a social media platform surveyed 40,000 people between 13 and 40. They came from 16 different countries, including Germany, Japan, USA, Saudi Arabia, India and Australia, and were representative of their countries.
Nearly half of the respondents would like to repair broken friendships.
#Snapchat (2020): The Friendship Report 2020. Insights on how to maintain friendships, navigate endships, and stay connected in COVID-19, p. 24
https://forbusiness.snapchat.com/blog/the-friendship-report-2020-global
Quote: “Given the pain of losing a close friend, it’s no surprise that many of
us want to get back in touch.
Nearly half (47%) of respondents said that they are interested in repairing a broken friendship. After a rupture, one of the most widely shared reasons for needing to repair a friendship is “missing the person” (35%), followed by “they apologized” (28%), and finding the conflict stressful (27%).”
#Liu, P. J. et al. (2022): The Surprise of Reaching Out: Appreciated More Than We Think. Journal of Personality and Social Psychology
https://www.apa.org/pubs/journals/releases/psp-pspi0000402.pdf
Quote: “We find evidence compatible with an account wherein one reason this underestimation of appreciation occurs is because responders (vs. initiators) are more focused on their feelings of surprise at being reached out to. A focus on feelings of surprise in turn predicts greater appreciation. We further identify process-consistent moderators of the underestimation of reach-out appreciation, finding that it is magnified when the reach-out context is more surprising: when it occurs within a surprising (vs. unsurprising) context for the recipient and when it occurs between more socially distant (vs. socially close) others. Altogether, this research thus identifies when and why we underestimate how much other people appreciate us reaching out to them, implicating a heightened focus on feelings of surprise as one underlying explanation.”
Just as important as caring about others is reciprocity and openness.
An example of this is a study in which adolescents used various questionnaires to make statements about different aspects of intimacy (attachment style, sense of coherence, self-disclosure.) in relation to a friendship of course, intimacy itself.
#Bauminger, N. et al. (2008): Intimacy in adolescent friendship: The roles of attachment, coherence, and self-disclosure. Journal of Social and Personal Relationships, Vol. 25(3), pp. 409–428
https://journals.sagepub.com/doi/abs/10.1177/0265407508090866
Quote: “In sum, this study aimed to explore gender and grade-level differences in intimacy; correlations between intimacy, attachment, coherence, and self-disclosure; the contribution of attachment, coherence, and self-disclosure (while controlling for gender and grade level) as predictors of intimacy during adolescence; and to examine a mediational model of intimacy development in which self-coherence and self-disclosure mediate between attachment styles and intimacy in adolescence (e.g., see Figure 1). Based on the preceding literature review, we assumed that internal resources, namely a secure attachment with a primary caregiver and a strong sense of coherence, and external resources, namely self-disclosure with friends, would influence the development of intimacy during adolescence.”
The statistical analysis showed a clear correlation between self-disclosure and intimacy.
#Bauminger, N. et al. (2008): Intimacy in adolescent friendship: The roles of attachment, coherence, and self-disclosure. Journal of Social and Personal Relationships, Vol. 25(3), pp. 409–428
https://journals.sagepub.com/doi/abs/10.1177/0265407508090866
Quote: “Relationships among intimacy, attachment, coherence, and self-disclosure Table 3 presents the correlations among intimacy, attachment, coherence, and self-disclosure. All the correlations were statistically significant and in the expected direction. First, avoidant and anxious attachment correlated negatively with all the intimacy subscales and with the overall category. Second, all three dimensions of self-disclosure (family, friends, and physical appearance) correlated positively with all the dimensions of intimacy. Finally, a greater sense of coherence correlated with higher levels of all four intimacy dimensions and with the overall category.”
If this sounds a bit scary, the good news is that human brains are hardwired to seek connection.
The following book summarizes the research on the influence of social connection and draws evidence together from different areas like genetics, medicine, evolutionary biology, psychology and neuroscience. It has been helpful for us to gain a general understanding of the subject.
#Cacioppo, J. T. & Patric, W. (2008). Loneliness: Human Nature and the Need for Social Connection.
Following papers from the same author also provides evidence from neuroimaging and reviews literature on the evolutionary and neurobiological mechanisms of loneliness.
#Cacioppo S. et al. (2015): Loneliness and implicit attention to social threat: A high-performance electrical neuroimaging study. Cognitive Neuroscience, Vol. 7(1-4), pp. 1-22
Quote: “In sum, the current research provides additional information on how loneliness impacts the processing of threatening stimuli. For instance, the brain microstates evoked in lonely individuals varied as a function of social threats and nonsocial threats with fewer microstates evoked by social than nonsocial threats. The microstates evoked in
non-lonely individuals by social and nonsocial threats, in contrast, were similar in number with the early microstates showing striking commonality. The estimated regions of brain activation need to be validated in statistically well-powered fMRI studies (Button et al., 2013), but the present results suggest there were a greater number of evoked brain
microstates and a much richer spatial and temporal sequence of regional brain activation than hypothesized and observed in prior research.”
#Cacioppo, J. T. et aL. (2014): Evolutionary Mechanisms for Loneliness. Cognition and Emotion, Vol. 28 (1), pp. 3-21
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3855545/
Quote: “First, loneliness increases explicit attention to social stimuli and increases implicit attention to social threats have a counterpart in hunger. Hunger increases one’s attention to and motivation to find food. Not everything that appears edible is safe to eat by humans, however. Over an evolutionary timescale, our taste buds have developed to be much more sensitive to bitter (e.g., concentrations of 1:2,000,000) than to sweet (e.g., concentrations of 1:200). Poisons tend to have a bitter taste, so this difference in sensitivity has evolved to protect the individual from dangers that arise as a result of the drive to find food. Given it is more costly to fall victim to a fatal assault than to forego a friendship, becoming more sensitive to social threats may be beneficial, especially in environments populated by dangerous foes.”
#Cacioppo S. et al. (2016): Toward a Neurology of Loneliness. Psychological Bulletin, Vol. 140 (6), pp. 1464–1504
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5130107/
Quote: “Experimental studies show that social isolation produces significant changes in brain structures and processes in adult social animals. These effects are not uniform across the brain or across species but instead are most evident in brain regions that reflect differences in the functional demands of solitary versus social living for a particular species. The human and animal literatures have developed independently, however, and significant gaps also exist. The current review underscores the importance of integrating human and animal research to delineate the mechanisms through which social relationships impact the brain, health, and well-being.”
Following book also compiles the relevant research in social neuroscience and social connection as a primary drive of human behavior.
#Lieberman, M. D. (2014): Social: Why Our Brains Are Wired To Connect.