Loneliness: Human Nature and the Need for Social Connection

A Q&A with John T. Cacioppo, Ph.D. University of Chicago

What is social neuroscience?

 We like to think of ourselves as mythic individualists, but humans are fundamentally a social species. As a social species, we create emergent organizations beyond the individual – structures that range from dyads, families, and groups to cities, civilizations, and cultures. These emergent structures evolved hand in hand with neural and hormonal mechanisms to support them because the consequent social behaviors helped these organisms survive, reproduce, and care for offspring sufficiently long that they too survived to reproduce. Social neuroscience represents an interdisciplinary approach devoted to understanding how biological systems implement social processes and behavior and to using biological concepts and methods to inform and refine theories of social processes and behavior.

Please tell us about the research you conducted for your book, Loneliness.

To examine the role of the social world on neural, hormonal, and genetic mechanisms, we have compared the differences between individuals who are or feel socially isolated from those who do not. A wide variety of differences have been documented in socially isolated versus socially housed animals, including decreased lifespan in the Drosophilia melanogaster (fruit fly) to obesity and Type 2 diabetes in mice. Human studies have similarly found social isolation to be associated with higher rates of morbidity and mortality.

Our own research has focused on analyses including brain imaging, autonomic and neuroendocrine assays, gene transcript analyses, twin studies, sleep studies, and various psychological and behavioral analyses. We have drawn upon a large number of cross-sectional studies of lonely young and older adults; various experimental studies in which we manipulate loneliness; longitudinal studies of twins and their families; and longitudinal studies of middle-aged and older adults in Chicago. As we discuss in our book, one of the surprising early findings was that experimentally manipulating loneliness produced changes in a wide variety of other psychological and behavioral states, including self-esteem, depressive mood, anxiety, hostility, shyness, and social skills, that were as dramatic as those we observed in cross sectional studies. Our longitudinal studies have confirmed that loneliness appears to cause a wide variety of potentially deleterious effects on neural, hormonal, and genetic mechanisms as well as on health, cognition, and well being.

How does loneliness differ from physical isolation or solitude?

Physical isolation can contribute to feelings of loneliness, but people can be lonely in a marriage, family, or crowd. Loneliness is the pain you feel when your need for connection isn’t being met, and you can feel that anywhere—even when surrounded by friends or family. What matters is how you feel about it, your subjective response. The pain of being alone is termed loneliness, whereas the bliss of being alone is termed solitude. We and others have found that it is not the number of friends or contact that predicts loneliness, it is the quality of those relationships.

Can people be surrounded by family and friends and have a very active social life and still be lonely?

 Yes, for instance, freshman when they arrive at college are sharing housing and are surrounded by hundreds of other students, yet on average their feelings of loneliness are heightened by the fact that they have severed their normal ties with friends and family, in many instances for the first time in their lives. Similarly, a bereaved spouse may suffer the searing pain of loneliness despite the presence of more supportive family and friends than typically are around them. But it does not require a life-changing event to find oneself lonely in the midst of an active social life. The frenetic pace with which many in contemporary society move from work to family obligations to social activities can leave one feeling at a loss for any meaningful human contact.

About a quarter century ago, when Americans in a national survey were asked the number of confidants they had, the most frequent response was three. This question was asked again a few years ago, and the most frequent response was zero. This finding is consistent with the robust finding that it is the quality of our social relationships, not the quantity, which is an essential part of what it takes for us to be healthy and happy.

Where was the science of loneliness when you entered the field? How is your view different?

 The science previously tended to characterize loneliness as an aversive state with no redeeming features, and as a state barely different from general negativity or depressed mood. Our research suggests a very different depiction of loneliness. We have adopted the perspective of loneliness as a biological construct, a state that has evolved as a signal to change behavior – very much like hunger, thirst, or physical pain – that serves to help one avoid damage and promote the transmission of genes to the gene pool. In the case of loneliness, the signal is a prompt to renew the connections we need to survive and prosper.

Do you think that American culture influences people to devalue human connection and community?

 Our culture stands on both sides of this continuum. We espouse that “united we stand, divided we fall,” and we celebrate the achievements of the solitary individual. Humans are fundamentally social creatures, however, and our strength and considerable capacity as a species comes from our collective connectedness, not our individual might.

What role did loneliness play from an evolutionary perspective?

 Our work with brain scans, physiological markers, and heritability analyses has allowed us to put loneliness into an evolutionary context that underscores its utility. Early in our history as a species, we survived and prospered only by banding together—in couples, in families, in tribes—to provide mutual protection and assistance. Loneliness evolved like any other form of pain. As noted above, this was a prompt to renew the connections we needed to insure survival and to promote social trust, cohesiveness, and collective action. Hunger, if ignored, can be followed by ravaging effects on the brain and biology, ultimately reducing a person’s ability in the wild to find and capture food. Loneliness, too, if ignored can have damaging effects that make it more difficult for an individual to escape its grips. Moreover, when offspring have long periods of abject dependency, simply bearing offspring is not sufficient to ensure one’s genes make it into the gene pool. One must also care enough about these offspring to care and nurture them so that they too live long enough to reproduce.  Thus, loneliness is a prompt to reconnect with others to protect our survival and the survival and perpetuation of our genes.

 Is there a genetic variation among individuals in their need for social connection?

 Yes, loneliness is about 50% heritable, but this does not mean loneliness is determined by genes. An equal amount is due to situational factors. What appears to be heritable is the intensity of pain felt when one feels socially isolated. Being sensitive or insensitive are each fine, but what is important is to create a social environment that matches one’s predisposition toward feeling social pain. If one is especially sensitive, then it may benefit one’s health and well being to prioritize the development and maintenance of a few high quality relationships.

Many social scientists and psychologists compare the human brain to an intricate, solitary computer and to humans as being driven primarily by ruthless competition and narrow self-interest. Does your research support this theory?

The dominant metaphor for the scientific study of the human mind during the latter half of the 20^th century has been the computer – a solitary device with massive information processing capacities. Our studies of loneliness left us unsatisfied with this metaphor. Computers today are massively interconnected devices with capacities that extend far beyond the resident hardware and software of a solitary computer.

It became apparent to us that the telereceptors (e.g., eyes, ears) of the human brain have provided wireless broadband interconnectivity to humans for millennia. Just as computers have capacities and processes that are transduced through but extend far beyond the hardware of a single computer, the human brain has evolved to promote social and cultural capacities and processes that are transduced through but that extend far beyond a solitary brain.

To understand the full capacity of humans, one needs to appreciate not only the memory and computational power of the brain but its capacity for representing, understanding, and connecting with other individuals. That is, one needs to recognize that we have evolved a powerful, meaning-making social brain. This social brain is not always a benevolent brain, however. Our research certainly says humans have the capacity to be driven by ruthless competition and narrow self-interests, but it also shows that we have an additional, wondrous capacity to cooperate, care about others as well as oneself, and compete in fair and mutually beneficial ways. As a society, it may be important to find ways to promote the latter over the former in individuals. 

You argue that loneliness can have serious physiological consequences. Could you please share your research on this issue?

 As we discuss in our book, loneliness can cause:

        •       Increased vascular resistance, or resistance to blood flow throughout the body

•          Elevated blood pressure as one ages

•          Increased rises in the stress hormone, cortisol, in the morning and heightened hypothalamic pituitary adrenocortical activity

•          Under-expression of genes bearing anti-inflammatory glucocorticoid response elements (GREs) and over-expression of genes bearing response elements for pro-inflammatory NF-κB/Rel transcription factors – that is, altered gene expressions in immune cells

•          Less salubrious sleep

•          Higher levels of depressive symptoms and lower life satisfaction

•          Poorer executive function

•          Poorer health behaviors such as exercise

•          Brain circuitry indicative of less rewarding in response to pleasant social stimuli, and more attention and less perspective taking in response to unpleasant social stimuli

 In addition, in our book, we review evidence that loneliness is associated with:

• Progression of Alzheimer’s Disease

• Obesity

• Diminished immunity

• Reduction in independent living

• Alcoholism

• Suicidal ideation and behavior, and

• Poorer health

What are the long-term effects of chronic loneliness?

Over time, loneliness can impair our ability to exercise self-control and delay gratification and it can compromise our executive functioning. It interferes with judgment, complex thought, will power, and perseverance as well as one’s ability to read other people.

 What causes some people to get stuck in “chronic” loneliness?

 Because loss of social connection was such a threat, loneliness engenders fear as well as pain. For each of us, our need for social connection and our sensitivity to social pain is biased by our individual genetic inheritance. Fear-based responses, understandably, prompt us to look out for ourselves, which can interfere with the accurate perceptions we need to effectively connect with others and the selection of the social skills or appropriate social responses in any given occasion. Thus, when a person becomes lonely, he or she can get caught in a feedback loop in which the undercurrent of danger and threat associated in evolutionary terms with social isolation can promote a form of social cognition and interaction that becomes a self-perpetuating, self-fulfilling prophecy.  

Could you share with us some of the solutions for the individual and society to decrease loneliness and to increase connection and social cooperation?

We go into this in some depth in our book. Briefly, our individual, sometimes distorted perceptions contribute to the physiological and chemical effects that accompany loneliness. Thus, we can make significant change, even at the physiological level, through techniques based on cognitive therapy, which consists largely of reframing one’s thoughts. Mostly, the solution lies in getting beyond the fear in order to be more available to others, which then provides the positive, almost therapeutic physiological responses that our bodies are more than willing to provide through normal social connection.

 A second key ingredient is to carefully select those with whom one seeks to develop a relationship. People do not need to be liked by or connected to everyone. It is not the quantity but the quality of one’s relationships that matter most. The research is clear that similarity – similar attitudes, values, interests, and activities – are an important foundation upon which to build such relationships.

Further Reading:

Cacioppo, J. T., & Patrick, W. (2008). Loneliness: Human Nature and the Need for Social Connection. New York: W. W. Norton & Company, Inc.