How Chronic Pain Can Change How Your Brain Sees You

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Scientists just found the spot in your brain where back pain stops being a symptom and starts being part of who you are.

Story Snapshot

Researchers at University of California San Diego scanned 114 chronic low back pain patients during a real pain flare.
A leg-raise test that triggered pain lit up the brain’s Default Mode Network, the circuit tied to self-identity.
The same network did the opposite during a separate, short-lived heat pain test on the same people.
Worse chronic pain matched stronger links between that identity network and the brain’s sensory processing areas.

What The New Brain Scans Actually Showed

Researchers at UC San Diego ran 114 people with chronic low back pain through a leg-raise test built to trigger a real pain flare. While the flare hit, they measured blood flow in the brain using a functional MRI technique called arterial spin labeling. The same participants also received a separate, short burst of painful heat on the calf so scientists could compare two very different pain experiences in the same brains. The results, published in the British Journal of Anaesthesia, showed something unexpected. Movement-triggered back pain increased activity in the Default Mode Network, a set of connected brain regions in the front, side, and back of the brain. The painful heat test did the opposite, lowering activity in that same network, which matched what scientists usually expect during ordinary acute pain.

That split matters because the Default Mode Network isn’t just another pain pathway. Scientists call it the brain’s “self network.” It switches on when people reflect on their own identity, replay personal memories, or sit with their own thoughts and feelings. UC San Diego researchers say this is the first time anyone has shown chronic pain flares switching that network on, rather than off.

Why Researchers Call This A Window Into Identity

Fadel Zeidan, the study’s corresponding author and director of UC San Diego’s Pain Health and Mindfulness Laboratory, put it plainly. “What we show for the first time ever is that when you have a pain flare, it turns on instead,” he said. “You start to identify the experience with who you are.” That statement captures the core claim driving the entire study. The data got more specific the worse the pain got. Patients with more severe chronic low back pain showed stronger connections between the self-identity network and the primary somatosensory cortex, the brain region that processes touch and body sensation. Separately, the more pain someone felt during the leg-raise test, the more activity showed up in sensory and motor brain regions. Pain intensity and brain-network behavior moved together.

This isn’t an isolated idea in pain science. Other researchers studying chronic pain have already described how pain-related signals can become functionally wired into the self-representing Default Mode Network the longer pain sticks around, turning it into what some scientists call an intrinsic part of a person’s self-image. That lines up with decades of patient interviews showing people with long-term pain often describe rebuilding their goals, routines, and sense of who they are around the pain itself.

What This Does Not Yet Prove

The study is observational, meaning it shows a connection between a pain flare and brain-network activity, not proof that pain rewires someone’s personality or changes who they fundamentally are. The research measured blood flow and brain signals, not validated psychological tests of identity, memory, or self-concept. Making that leap is reasonable as a theory, but it’s not something this particular scan proved on its own. The comparison between a leg-raise test and painful heat applied to the calf also isn’t a perfectly even fight. One stimulus comes from a person’s own back condition during movement; the other is an external jolt at a different body part. Scientists studying brain-pain links elsewhere have warned that assuming a brain region “means” pain, identity, or anything else just because it lit up during a test can be a logical trap if that same region activates during other mental states too. That’s a caution worth keeping in mind, not a reason to dismiss the finding.

A surprising discovery at UC San Diego suggests that chronic lower back pain may become deeply embedded in the brain's sense of personal identity. Researchers found that movement-triggered pain activates a brain network associated with self-awareness and mhttps://t.co/BpmwGVoHXz

— Michael W. Deem (@Michael_W_Deem) October 30, 2026

None of this changes what patients already know in their bones: chronic back pain doesn’t stay in the back. It follows people into their sense of self, their mood, and their daily choices, which is exactly why standard painkillers so often fall short for this population. This study gives that lived experience a biological fingerprint, even if turning that fingerprint into a new treatment still requires years of follow-up trials testing whether calming this brain network actually eases pain.