When Your Body Keeps You Guessing
You hear a rustle in the bushes while walking alone at night.
Is it the wind? Is it an animal? You probably wouldn't wait to find out before deciding how to respond.
From an evolutionary perspective, that response makes sense. When missing a real threat is more costly than reacting to a harmless one, evolution may favor responding early.¹ The brain also uses past experiences to learn which signals may predict danger and how to respond to them.²
But what happens when the thing you're trying to predict is what your own body will feel next?
For someone living with chronic symptoms, the “threat” may not be a predator or an obvious injury, but an unfamiliar sensation that appears without warning and has no clear explanation.
Is this normal? Is it getting worse? Will it happen again?
Living with chronic symptoms can mean asking questions that have no immediate answer. And asking those questions requires work.
Pain is More Than a Feeling
We often think of pain as a simple alarm: something happens to the body, nerves detect it, and the brain produces pain. But pain is more complicated than a measurement of tissue damage.
The International Association for the Study of Pain defines pain as a personal experience influenced by biological, psychological, and social factors, and distinguishes pain from nociception—the detection of potentially harmful stimuli.³
One of the clearest examples is phantom limb pain. After an amputation, some people continue to experience sensations, including pain, in a limb that is no longer physically present. Changes in how the brain perceives the missing limb and processes sensory information can contribute to these experiences.⁴
If pain were simply a measure of physical damage, phantom limb pain would be difficult to explain.
Instead, pain is an experience shaped by the nervous system as it interprets information from and about the body. It is not simply a message sent from an injured body part to the brain.
Our Expectations Can Change How We Feel Pain
The brain uses past experiences and expectations to anticipate what might happen next, which can influence how intensely we experience pain.⁵
This helps explain the nocebo effect: when people expect a treatment or experience to be harmful, that expectation can contribute to greater discomfort or more pronounced symptoms. In other words, what we expect to happen can influence what we feel happening in our bodies.
A 2024 review involving more than 8,000 participants found that negative expectations can worsen symptoms, with the effect becoming stronger when past experiences reinforced those expectations.⁶
Usually, prediction is protective. But chronic symptoms create a difficult problem: what happens when the brain is repeatedly asked to predict something that isn't predictable?
A new sensation becomes something to interpret:
Is today's pain different from yesterday's?
Did I sleep differently?
Was I more stressed?
Is this a pattern or a coincidence?
The person experiencing the symptom is doing the work of constantly interpreting what it means.
When Paying Attention Becomes Work
Chronic symptoms don't just demand attention. They take up time.
Living with chronic symptoms can mean searching for possible explanations, tracking changes, preparing questions, and deciding when something warrants further attention.
A review of research on chronic illness found that patients may spend two hours a day or more on health-related activities, including managing symptoms and treatment and interacting with the healthcare system.⁷
But the burden isn't necessarily confined to those two hours. Unlike traditional forms of work, this labor does not have defined hours or clear outcomes. There is no moment when a patient can officially "clock out" of managing their health.
You might check a symptom in the morning, think about it during work, search for an explanation that afternoon, and wonder whether it will happen again before bed. Even when nothing is actively happening, part of your attention can remain focused on what your body might do next.
Pain doesn't exist in isolation from the rest of the body or daily life. Sleep, for example, has a surprisingly close relationship with pain. A systematic review and meta-analysis of 116,746 people found evidence that the relationship between sleep problems and chronic musculoskeletal pain is bidirectional: poor sleep was associated with a greater risk of developing chronic pain, while chronic pain was also associated with subsequent sleep problems.⁸
Stress and other aspects of daily life can also influence how pain is experienced. Research on illness uncertainty describes it as a cognitive stressor and has linked it to psychological distress, reduced quality of life, and, in pain populations, greater pain sensitivity and lower pain tolerance.⁹
The body doesn't have to be actively hurting for illness to occupy mental space.
Moving Toward a Holistic Approach
A symptom rarely exists on its own. It is part of a larger network of factors that shape how we experience our health, many of which may be difficult to recognize in isolation.
A more holistic approach to healthcare means looking beyond individual symptoms and understanding the patterns between them. Technology has made it easier to collect information about our health, but collecting information is only the beginning. The real value comes from being able to make sense of it—to recognize connections that may be difficult to see when we experience each symptom, habit, or change on its own.
Perhaps the next step in healthcare is not asking patients to do more work, but using technology to make sense of the work they are already doing.
The goal is not to make patients better at monitoring themselves. They already are good at it.
It is to make their health easier to understand—and, ultimately, easier to live with.
References
- Haselton & Nettle, 2006
- Levy & Schiller, 2021
- International Association for the Study of Pain, 2020
- Collins, et. al., 2018
- Atlas & Wager, 2012
- Rooney et al., 2023
- Jowsey et al., 2012
- Runge, et. al., 2024
- Wright, et al., 2009
