There are examples of extremely severe injuries that, surprisingly, do not cause pain. At the same time, there are situations in which stimuli that would normally not be painful become highly unpleasant experiences.

To understand why this happens, it is necessary to introduce the concept of the neurosignature. A neurosignature can be defined as a network formed by the set of neural connections that integrate thoughts, memories, and personal experiences related to a specific topic, in this case, the experience of pain. This network allows apparently neutral stimuli, such as a song, a word, a smell, or an action, to activate a “switch” that leads us to experience pain, even in the absence of actual tissue damage.

Because this concept can be complex, visual resources can be helpful in understanding it. The following video illustrates this mechanism clearly:https://www.videoman.gr/es/153820

Based on this video, a key question arises: what is happening to the child? The child has not suffered a blow or trauma that would justify crying. However, the child is experiencing pain. Why? Because the child is surrounded by multiple stimuli that reinforce the association with the pain experience: the father asks how the child feels, touches the head, and uses a softer, more protective tone of voice. This is not conscious simulation. All of these elements lead the child to interpret that an injury has occurred, and as a result, the brain activates the pain neurosignature. Pain is experienced even though no physical damage has taken place.

Understanding this concept is especially relevant for people living with chronic pain. When the pain-related neurosignature is repeatedly activated, the system becomes increasingly sensitive. This process, known as the “wind-up” phenomenon, means that the pain “switch” is triggered more easily. Stimuli that previously needed to be intense or prolonged begin to activate pain with weaker input and in a shorter amount of time. A useful metaphor to understand this process is walking through a wheat field: the first time it is difficult to make a path, but if the same route is taken every day, the path becomes clearer and easier to follow.

This sensitization does not depend solely on external factors, such as a song, a smell, a place, or a person that reminds us of an unpleasant experience. It can also originate within the individual. The brain functions like the chief executive officer of a company: it constantly requests information from its “employees”, the joints, organs, and different systems of the body. When a body region hurts persistently, the brain demands more reports about it. As a result, it receives more information and pays greater attention to that area.

This state of hypervigilance makes it easier for the pain pathway to activate more rapidly, easily finding the route to the switch that triggers the pain experience. In this way, pain stops being merely a signal of tissue damage and becomes a learned response, amplified by the nervous system itself.

Ultimately, pain can be understood as an alarm system, and like any alarm, we expect it to sound when it should. We want a car alarm to activate if someone tries to steal the vehicle. Nevertheless, in chronic pain, the system becomes overly sensitive, and the alarm may go off in response to harmless stimuli. Things that did not hurt before, now do.

What causes this alarm system to become so sensitive? Some of the most important factors include unsuccessful treatments, personal problems, fear, anxiety, excessive focus on pain, and family or work-related context, among others. The issue is not only that the alarm sounds when it should not, but also that sometimes we are unable to turn it off, so it keeps ringing.

Maintaining a healthy diet, getting restorative sleep, exercising regularly, and taking care of emotional well-being are strategies that help quiet the alarm system and reduce pain intensity.