Predictive Processing: Why the Brain Sometimes Gets It Wrong

For many years, people assumed that the brain functioned rather like a camera. Information from the body and the outside world was thought to travel to the brain, where it was accurately interpreted and experienced. If you felt pain, the assumption was that pain signals had travelled from injured tissue to the brain. If you felt dizzy, fatigue, or breathless, those sensations were assumed to directly reflect what was happening in the body. Modern neuroscience paints a more complex picture. According to the theory of predictive processing, the brain is not simply reacting to incoming sensory information. Instead, it is constantly trying to predict what is happening before all of the sensory information has even arrived. In other words, perception is not simply something that happens to us. It is something the brain actively constructs.

The brain as a prediction machine

Every second, your brain receives an enormous amount of information from your eyes, ears, muscles, joints, internal organs, skin, and nervous system. Processing every piece of information from scratch would require an extraordinary amount of energy. Instead, the brain works more efficiently. Using memories, previous experiences, emotions, beliefs, learning, and the current situation, it continuously generates predictions about what it expects to experience. Incoming sensory information is then compared with these predictions. When the sensory information matches what the brain expected, perception feels effortless. When there is a mismatch known as a prediction error, the brain updates its understanding and adjusts future predictions. This constant cycle of prediction and correction allows us to navigate an incredibly complex world quickly and efficiently.

Why predictions matter

Most of the time, this system works remarkably well. If you pick up your morning coffee cup, your brain already predicts how heavy it will feel. If you hear your own front door opening, your brain immediately predicts who is likely to be entering. Without these predictions, everyday life would become painfully slow and cognitively exhausting. Prediction is therefore not a flaw in the brain. It is one of its greatest strengths.

When predictions become unhelpful

Problems arise when the brain learns predictions that no longer accurately reflect what is happening. Following an injury, illness, period of chronic stress, or repeated episodes of pain, the brain may begin predicting danger even after the original threat has resolved. As a result, normal bodily sensations may increasingly be interpreted as signs of pain, fatigue, dizziness, breathlessness, nausea, or other symptoms. Importantly, this does not mean the symptoms are imagined. The symptoms are genuine experiences produced by the brain's interpretation of sensory information. Just as optical illusions demonstrate that the brain can misinterpret visual information, persistent physical symptoms may reflect the brain making its best, but sometimes inaccurate, prediction about what is happening inside the body.

Learning shapes perception

Our brains are constantly learning. Every illness, injury, emotional experience, medical consultation, frightening symptom, reassuring test result, and previous recovery contributes to future predictions. If someone repeatedly experiences severe back pain whenever they bend over, the brain may eventually begin predicting pain before movement even occurs. Similarly, someone who has experienced repeated episodes of dizziness, panic attacks, migraines, or gastrointestinal symptoms may become increasingly sensitive to subtle bodily changes that previously would have gone unnoticed. The prediction itself can amplify attention toward those sensations, making them feel stronger and more convincing.

Why this matters for persistent symptoms

Predictive processing provides one possible explanation for why symptoms sometimes continue despite healing of the original injury or illness. Rather than viewing symptoms as arising solely from damaged tissues, this framework suggests that perception reflects an ongoing interaction between incoming sensory information and the brain's expectations. In persistent pain, for example, the nervous system may become increasingly efficient at predicting pain. In functional neurological symptoms, predictive models have been proposed to explain alterations in movement, sensation, or awareness. Similarly, chronic fatigue, dizziness, tinnitus, and other persistent symptoms may involve prediction processes interacting with changes in nervous system sensitivity, emotional states, previous learning, and environmental cues. Importantly, predictive processing does not replace biological explanations. It expands them.

What this means for recovery

One of the encouraging implications of predictive processing is that predictions can change. Just as the brain learned particular expectations through experience, it can gradually learn new ones. This is why many evidence-based approaches to persistent symptoms aim not simply to reduce symptoms but to help the brain update its predictions. Education, graded exposure, behavioural experiments, emotional processing, reducing fear of symptoms, and gradually returning to meaningful activities may all provide opportunities for the brain to gather new evidence that challenges old expectations. Recovery is therefore understood not as convincing yourself nothing is wrong, but as helping the brain build increasingly accurate predictions about what the body is capable of doing.

A new way of understanding symptoms

Predictive processing offers an important framework for understanding why very real symptoms can persist even when structural damage is absent or no longer sufficient to explain their severity. Rather than asking whether symptoms are physical or psychological, this model encourages a different question: How has the brain learned to interpret the body's signals? For many people living with persistent physical symptoms, this shift in perspective is both scientifically grounded and deeply validating. It recognizes that symptoms are real while also acknowledging the brain's remarkable capacity to learn, adapt, and, ultimately, change.

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Dr. Ingela Thuné-Boyle provides specialized online coaching for adults living with chronic illness, chronic pain, persistent physical symptoms, and mind-body syndromes. She helps people better understand their symptoms, develop effective self-management skills, and improve their quality of life. A UK Chartered & Practitioner Health Psychologist (HCPC) and Doctor in Behavioural Medicine with over 25 years of experience, she brings an evidence-based understanding of the psychological, behavioural, and physiological factors that influence health and wellbeing to her coaching. Learn more about her background [here] and her coaching approach [here].

📩 Contact: For coaching or other enquiries, you can contact her at info@ingelathuneboyle.com.

Please note: Advice given in this blog is not meant to take the place of coaching, therapy or any other professional advice. The opinions and views offered by the author is not intended to treat or diagnose, nor is it intended to replace the treatment and care that you may be receiving from a licensed physician or mental health provider. The author is not responsible for the outcome or results following their information and advice on this blog.