We’re Reshaping Our Brains With Loneliness and ADHD

We’ve created a vicious feedback loop of societal change that threatens us all

Awash amid seas of internet connectivity, and often living far from where we grew up, we’re drowning in loneliness. Despite having ways to interact that our grandparents never imagined, many of us feel disconnected and isolated. Surgeon General Vivek Murtha issued only two Health Advisories in 2023, one on loneliness, and the other on social media use and mental health in youth. In both, he beseeched us to pay attention to how we are changing the ways we relate to one another, because we are causing serious harm to our bodies and communities. Loneliness is actually killing people.

Much of the mental health impact of loneliness has focused on how it increases the likelihood of dementia in the elderly and the risk for depression across all ages. We’ve paid less attention to the fact that loneliness is associated with a deterioration in capabilities central to attention deficit hyperactivity disorder (ADHD): including short-term memory, attention, impulse control, and emotional regulation.

Loneliness adds to ADHD symptoms, but ADHD also contributes to loneliness.

Loneliness is shoving all of our brains further along the ADHD spectrum. Those who already have ADHD will demonstrate more severe problems. Some with mild symptoms will be pushed into having full-blown ADHD. Many of us will suffer from more moments of inattention, distractibility, and frustration.

Our actions as individuals are changing our whole social environment in ways that potentially create millions of new cases of loneliness, and of ADHD. We are doing so blindly, without much awareness. If we want to avert this societal shift, we need to grasp more firmly the ways in which we are harming ourselves.

Only the lonely?

Social isolation describes the situation of having limited interactions with others. It can be measured in terms of the number of close contacts, the frequency of interactions, or hours a day spent with others. Loneliness, in contrast, is a subjective feeling that one’s social connections are inadequate. Although social isolation and loneliness overlap substantially, some isolated people are content with their solitude. Others who appear to have extensive social engagements actually feel disconnected and lonely.

Research indicates that loneliness and social isolation have separable, distinct, negative impacts on physical and mental health. Yet current research methods don’t generate an accurate portrait of either problem.

Psychologists usually measure loneliness by asking one, or at most a handful, of questions regarding one’s subjective sense of inadequate connection to others. This causes a problem for research, because like ADHD, loneliness exists on a spectrum of severity. When we force people into a yes/no response, some individuals will be lumped into the wrong group, which weakens the findings based on such research.

ADHD arises in childhood, and persists into adult years for about two- thirds of those children. In addition to those with full-blown ADHD, at least as many individuals display sub-threshold levels of ADHD; the condition exists on a spectrum of severity. Genes contribute strongly to the development of ADHD, but the environment plays a role as well.

Further compounding the inaccuracies, many studies collect data at just one point in time, comparing the presence of loneliness to some other variable of physical or mental health. At best, that research can show an association. For example, coronary heart disease is linked to loneliness. But simple correlations can’t show which was cause and which effect.

Longitudinal studies, looking at loneliness at multiple points in time, and looking for later associations with health outcomes, can provide more insight into possible causation. Such research reveals that pervasive loneliness appears more toxic than just feeling lonely at one point in time.

The definitive way to demonstrate causality is to run controlled experiments, randomly subjecting some individuals to loneliness and comparing them to others. Extreme studies of depriving youngsters of their parents demonstrate that inducing extreme loneliness has profound and pervasive detrimental effects on physical and mental health.

In the 1950s, psychologist Harry Harlow used wire-frame mother monkeys to show that baby monkeys supplied with milk and physical warmth but deprived of maternal contact developed severe problems interacting with other monkeys as they grew up. Romanian children left in orphanages, provided with adequate physical care, but minimal intimate connections with humans, developed pervasive mental and physical health problems compared to those children who found foster homes. The evidence that loneliness causes massive damage to emotional health is so clear-cut that such experiments are no longer allowed, ethically.

The recent COVID pandemic, and the ensuing restrictions on previously normal patterns of interaction, did provide a “natural” experiment on social isolation and loneliness, and generated dozens of studies. In general, those with ADHD tended to feel more loneliness during the pandemic than those without ADHD, and their isolation prompted more distress and dysfunction.

Why loneliness hurts

Humans have been social animals for millions of years. For mammals our size, equipped with our teeth, our muscles, our thin skins, and our brains, banding together in groups was essential for survival. Lone humans couldn’t ward off the big cats, dogs, and bears that wanted to eat us. Individuals faced big challenges in finding and gathering the diversity and volume of plants needed to survive. Catching enough game or fish to provide sufficient high quality protein was easier as a cooperative venture. Solo humans simply died.

The necessity of remaining part of a group was built into our brains. Being lonely hurts. The pain of social isolation and pain from physical trauma share much of the same brain-pain circuitry.

Pain delivers to the rest of the brain these messages: This is really important! This is really bad! You need to do something to change this! In response, people pull their hand out of the campfire, or stop walking on their broken ankle, or try to reconnect with the brother who just snarled at them.

Loneliness produces toxic effects that rewire the brain through poisons and through patterns. Poisons include chemicals like cortisol, and adrenaline. In the short term these provide useful information within the brain, motivating us to face a fear or run from it. But after prolonged exposure — the sort of stress induced by chronic loneliness — those chemicals act directly to kill brain cells and prune nerve cell connections.

Loneliness also damages the brain through the patterns of neural activity it induces. Nerves that fire together get wired together. By reducing interactions with others, social deprivation narrows our repertoire — we don’t practice certain skills, so they wither. Even worse, we over-engage in rumination and worry about our lonely social status, which over-strengthens what neuroscientists call the default mode network, as well as reducing connections to attentional circuits in the brain.

Loneliness degrades our brains.

ADHD causes loneliness

Although there have been a few exceptions, dozens of studies demonstrate a connection between ADHD and a greater likelihood of loneliness. This effect is seen in children, adolescents, and adults, and in men and women. The connection is only partly explained by other co-occurring mental health conditions; even with depression pulled from the picture, ADHD is still associated with loneliness. The more severe the ADHD, the greater the likelihood of loneliness.

That doesn’t mean that everyone with ADHD feels lonely or is isolated. Many with ADHD are well adjusted individuals, valued by their friends for their spontaneity and their enthusiasm during social events.

Some of the susceptibility to loneliness appears to be under genetic control. But looking at group averages, studies show that those with ADHD have a greater likelihood of…

• relationship difficulties
• poor relationship quality
• being single
• divorce
• suicide

Explanations for the greater prevalence of loneliness among those with ADHD examine the interaction between these neurodivergent individuals and society. In many social settings, people perceive differences as undesirable, and subject people with ADHD to negative feedback, criticism, and rejection.

Because of inattention, people with ADHD are more likely to miss social cues — they might not see someone’s facial expression, they may miss who had higher status in the hierarchy, and they often don’t realize it isn’t their turn to speak.

Not following social norms causes conflict. Conflict produces social withdrawal, isolation, and loneliness.

Of note, those with ADHD usually comprehend social communication when it’s pointed out — they simply weren’t attending to those details. In contrast, a core symptom of those on the autism spectrum is problems processing social communication. Even when social cues are explained, the autistic individual still doesn’t perceive them as meaningful, relevant, or reasonable.

The impulsive and hyperactive aspects of ADHD can lead to invading the personal space of others. This includes behaviors like:

• physically stepping on others’ toes
• bumping into others
• fidgeting noisily without awareness of distracting others
• standing too close while talking
• cutting off others in conversation
• being too candid or brutally honest in conversation

All of these behaviors contribute to the likelihood of social rejection by others, with consequent social isolation and loneliness.

Hyper-focusing, or becoming so absorbed in a task that one is oblivious to the rest of their environment, is one additional ADHD trait that can lead to loneliness. If you’re so busy coding that you don’t even realize that all of your co-workers have gone to lunch, you miss out on social connections. Others may mistake hyper-focusing as an intentional snub. Hyper-focusing may also drive how immersed one becomes in activities such as on-line gaming. Those with ADHD are substantially more likely to develop problems such as gaming addictions and excessive involvement in social media, which themselves are linked to loneliness.

Loneliness worsens ADHD symptoms

Although few studies have been designed to determine whether loneliness worsens ADHD, numerous research projects have shown that loneliness precedes deterioration in a number of cognitive functions. While some of these studies were looking for the impact of loneliness on the development of depression or dementia, they measured what psychologists call executive functions — mental skills involved in the control of behavior.

Executive function deficits are considered the cardinal features of ADHD. Loneliness precedes and is associated with:

• poorer impulse control
• poorer working memory
• poorer planning and organization
• poorer emotional regulation

A brain that marinates in loneliness is practicing these ADHD traits. It is rewiring itself to continue to act more often in ADHD-like ways. It is moving further along the ADHD spectrum of severity.

At the social level, more loneliness doesn’t just mean more detached and unhappy individuals, it also means more impulsivity, more distractibility, poorer retention of information, and greater emotional volatility when these people do interact.

The solution: Breaking the loop

When I talk with patients about feedback loops between loneliness and ADHD symptoms, their initial response is often one of despair. If loneliness and ADHD reinforce each other, doesn’t that mean there’s no escape, no chance of improvement?

My answer: A feedback loop implies just the opposite. The vulnerability of a feedback loop is that anywhere you break it, you disrupt reinforcement. So you can target the most accessible, or easiest part of the loop. You can dismantle it using your greatest strengths, or where you have the most resources.

The most important tools for breaking down the loneliness-ADHD connection are derived from cognitive behavioral therapy. These include:

• reframing and confronting fears of rejection
• learning social skills
• reinforcing attending to social cues
• learning to minimize distractions
• learning to make effective use of schedules and structure.

We can teach ways to rekindle the fundamental human ability to connect with others.

I also strongly encourage those with ADHD to be both proactive (warnings) and reparative (apologizing) with their social and work circles. One doesn’t necessarily have to mention their ADHD, one can simply describe ADHD-driven behavior. These instructions can be provided to peers, underlings, and supervisors, if your behavior has caused, or is likely to cause, problems in such situations.

An example would be “I know I have a tendency to talk at length in meetings (or run late, cut people off, or doodle during presentations.…). So if you see me doing that, please speak up.” You can even suggest what redirection would be helpful to hear from the other person at these moments.

I understand the reluctance to apologize after a social slip-up. Too often we feel ashamed of what we did, or ashamed that we didn’t even recognize the error until later, or worried that acknowledging our mistake will make it grow larger. But offered genuinely, most people appreciate an apology, especially accompanied with an indication of how one intends to minimize the likelihood of repeating problems in the future.

No loneliness pill

Both loneliness and ADHD affect the brain. Sometimes medications can provide powerful help in alleviating either condition.

We don’t have medications specifically tested or approved for loneliness. But loneliness is often compounded by, and intertwined with, social anxiety, which does tend to respond to medications like serotonin reuptake inhibitors (SSRI). SSRI can make it easier to initiate and sustain social interactions. I’ve also seen people, including those with ADHD, become more comfortable in formerly threatening social situations, through the use of buspirone, a serotonin receptor agonist approved for anxiety.

Given that ADHD severity predicts loneliness, stimulant medications, the most potent treatment for ADHD, may also help break the ADHD -loneliness cycle. While stimulants have their own potential for severe side effects, even individuals at the “milder” end of the ADHD spectrum often experience substantial symptomatic relief from these medications. Judicious use of medications should always be conducted in consultation with an experienced practitioner.

Loneliness is just one of the ways in which our modern world is promoting ADHD symptoms in the entire population. Our current societal approach to sleeping, eating, and exercise are creating additional feedback loops creating more ADHD-like behavior. Our increasing exposure to social media and screen time, and steeping our brains in seas of plastics and other pollutants also push us further along the ADHD spectrum. Many of these feedback loops interact with each other.

Loneliness has already scarred many of us. But as the Surgeon General has pointed out, this is not just a personal, but a social catastrophe. Even if you aren’t lonely, you’ve likely been deprived of connections with other people because of their loneliness.

Loneliness causes brains and societies to wither.

We need to start paying attention to the ways we are ruining our lives. Without addressing these problems, they won’t go away. The longer we wait, the less is our collective ability to collaborate and focus on what we need to change.