Studies have found that patients with Lyme disease experience exaggerated responses to pain and non-painful stimuli despite antibiotic treatment. Lopez-Sola and colleagues describe those same responses in patients with fibromyalgia — a condition associated with widespread musculoskeletal pain, fatigue, cognitive, emotional, and sleep-related symptoms.
In addition to pain-related changes, fibromyalgia patients show reduced tolerance to non-painful sensory stimulation — visual, auditory, olfactory, and tactile — along with abnormal brain processing of non-painful sensory stimuli.
Measuring the Brain’s Pain Response with fMRI
Lopez-Sola’s team used functional MRI (fMRI) to demonstrate an exaggerated response to pain and non-painful stimuli in fibromyalgia patients. The team exposed 37 fibromyalgia patients and 35 controls to painful pressure and non-painful visual, auditory, and tactile stimuli.
When people with fibromyalgia were exposed to painful stimuli, they had greater Neurologic Pain Signature (NPS) responses than those without the condition. Greater responses were also described for non-painful visual, auditory, and tactile stimuli.
The brain changes due to pain consisted of augmented responses in sensory integration and self-referential regions, and reduced responses in the lateral frontal cortex. Non-painful stimulation produced augmented responses in the insula, posterior cingulate, and medial prefrontal regions, with reduced responses in primary sensory cortices, basal ganglia, and cerebellum.
Why This Matters for Lyme Disease
The authors cautioned that exaggerated responses to pain and non-painful stimuli are not unique to fibromyalgia. Multifocal pain and widespread mechanical hypersensitivity are common features of multiple chronic pain conditions — including Lyme disease.
Exaggerated responses to pain and non-painful stimuli, frequently described in Lyme disease, could potentially be measured by fMRI to help assess therapeutic approaches and predict treatment response for individual patients.
Acute and chronic pain associated with Lyme borreliosis has been characterized as having qualities of neuropathic pain — radicular, deep aching, or lancinating pain, often worse at night, and associated with both sensory and motor findings. Chronic pain despite adequate antibiotic treatment of neuroborreliosis was reported by a substantial number of patients.
Sensory Hyperarousal in Lyme Disease
Lyme disease patients frequently report central sensitization or sensory hyperarousal. In patients with post-treatment Lyme syndrome, sensory hyperarousal was reported by a majority of patients after acquiring Lyme disease, most often affecting hearing and vision.
Hypersensitivity to sound may be limited to louder sounds, but in some individuals even the volume fluctuations in a normal conversation can be noxious. These patients might be seen wearing earplugs or sound-protectors in situations normally tolerable to others.
An individual’s life may be significantly altered by this hypersensitivity — wearing sunglasses indoors, avoiding daylight, and limiting work and social life. Hypersensitivity in other sensory modalities including olfactory, tactile, gustatory, and temperature has also been described. This pattern of sensory amplification overlaps significantly with what patients report as allodynia — pain from stimuli that should not normally hurt.
Clinical Perspective
This research provides a potential neuroimaging framework for understanding why Lyme disease pain persists despite treatment — and why patients report sensitivity to light, sound, and touch that goes far beyond what standard testing can explain. fMRI-based tools may eventually help clinicians assess the degree of neural pathology underlying individual patients’ pain symptoms and predict treatment response.
For now, the clinical implication is clear: exaggerated pain and sensory responses in Lyme disease patients are neurologically measurable, biologically driven, and should not be dismissed as psychological.
Frequently Asked Questions
Can the brain’s pain response be measured in Lyme disease?
Research using fMRI has demonstrated measurable, exaggerated brain responses to both painful and non-painful stimuli in conditions like fibromyalgia that share features with Lyme disease pain.
Why are Lyme disease patients sensitive to light and sound?
Central sensitization causes the brain to amplify sensory input. This can make normal levels of light, sound, touch, and smell feel overwhelming or painful.
Is Lyme disease pain the same as fibromyalgia?
They share overlapping features including widespread pain, cognitive symptoms, and sensory hypersensitivity. Some patients diagnosed with fibromyalgia may have an unrecognized tick-borne infection driving their symptoms.
What is central sensitization?
Central sensitization is a state in which the brain and spinal cord become hyper-responsive to both painful and non-painful stimuli, amplifying sensory signals beyond what the stimulus warrants.
Does this mean fMRI can diagnose Lyme disease pain?
Not yet. fMRI research provides a framework for understanding the neurology of chronic pain but is not currently used as a diagnostic tool for individual Lyme disease patients.
References
- Batheja S, et al. Post-treatment Lyme syndrome and central sensitization. J Neuropsychiatry Clin Neurosci. 2013;25(3):176–186.
- Zimering JH, et al. Acute and chronic pain associated with Lyme borreliosis: clinical characteristics and pathophysiologic mechanisms. Pain. 2014;155(8):1435–1438.
- Lopez-Sola M, et al. Towards a neurophysiological signature for fibromyalgia. Pain. 2017;158(1):34–47.
