Fibromyalgia as a disorder of perceptual organization? An analysis of acoustic stimulus processing in patients with widespread pain (Fibromyalgie als Störung der Wahrnehmungsorganisation? Eine Analyse akustischer Reizverarbeitung bei Patienten mit generalisiertem Schmerz)

Abstract

We examined to what extent patients with fibromyalgia differ from painfree control subjects in the perception and processing not only of somatosensory but also of external stimuli. For this purpose the acoustic perception of 30 patients with fibromyalgia was compared with that of 36 generally pain-free age and gender matched subjects. The groups were also controlled for organic disease of pathological dysfunction of the ear and auditory nerves. Thresholds of unpleasantness and hearing thresholds were determined autiometrically for various frequencies. In addition the participants rated their experience of daily noise, vulnerability to acoustic stress, and functional and affective complaints associated with fibromyalgia. As expected the results show reduced unpleasantness thresholds for all frequencies and a nonsymptomatic hearing loss for higher frequencies. The elevated hearing threshold correlated significantly with experience of noise at the place of work, which was also elevated in the fibromyalgia group. Generalized pain had a high impact on the interaction between threshold of unpleasantness and daily noise experience. We interpret the differences in thresholds of hearing and of unpleasantness in patients with fibromyalgia as a form of either preconscious or conscious acts to protect against disturbing stimulation. Our results support the notion of a generalized disturbancy of perceptual thresholds in patients with fibromyalgia not restricted to the perception of pain.

Altered Functional Magnetic Resonance Imaging Responses to Nonpainful Sensory Stimulation in Fibromyalgia Patients

“…The pattern of response attenuation in primary/secondary auditory cortices is congruent with existing evidence of poorer perceptual discrimination of auditory information including subclinical hearing loss for high frequencies (14) without peripheral underlying pathology in FM. It is also consistent with the observed amplitude reduction of ERP components (15–17) in response to auditory stimuli in these patients, and with the observation of lower resting cerebral blood flow in temporal and occipital cortices in FM (44).…”

“…Recent studies have shown a higher proportion of otoneurologic symptoms in FM patients in the absence of detectable peripheral sensory pathology (for example, see refs. 13 and 14). A study that specifically controlled for peripheral pathology found reduced unpleasantness thresholds for FM patients along a range of auditory stimulus frequencies (14), together with a subclinical hearing loss for specific frequencies.…”

“…13 and 14). A study that specifically controlled for peripheral pathology found reduced unpleasantness thresholds for FM patients along a range of auditory stimulus frequencies (14), together with a subclinical hearing loss for specific frequencies. Interestingly, electrical auditory event-related potentials (ERPs) in the brain mostly show reduced amplitudes in FM (for example, see refs.…”

Towards a neurophysiological signature for fibromyalgia

“…Consistently, Harte and colleagues very recently showed that fMRI data during a visual task could discriminate FM patients vs. healthy controls with 82% accuracy[29]. The Multisensory pattern shows early sensory cortical processing attenuation, which is consistent with reduced processing of fine sensory/discriminative properties of stimulus[1; 18; 46; 53], accompanied by amplification of sensory integration (in agreement with [29]) and self-referential aspects of the response, including potential threat of harm[17]. …”

Neurobiology of fibromyalgia and chronic widespread pain

“…These studies showed the following: (1) fibromyalgia patients are more sensitive to pressure anywhere in their body – tender points merely represent regions where everyone is more tender (Kosek et al, 1995, Wolfe, 1997, Petzke et al, 1999a, Graven-Nielsen et al, 2000), (2) randomly applied pressure pain threshold are not influenced by levels of distress of the individual, whereas tender point count is (Petzke et al, 1999b, Petzke et al, 2003a, Petzke et al, 2003b), (3) fibromyalgia patients were not any more expectant or hypervigilant than controls, (4) Pressure pain thresholds at any four points in the body are highly correlated with the average tenderness at all 18 tender points and control points (Petzke et al, 2001), (5) fibromyalgia patients also display a decreased threshold to other noxious stimuli, heat, cold, and electrical stimuli (Kosek and Hansson, 1997, Sorensen et al, 1998, Carli et al, 2002, Desmeules et al, 2003, Petzke et al, 2003a), and (6) fibromyalgia patients are more sensitive to other sensory stimuli such as sound (Gerster and Hadj-Djilani, 1984, Dohrenbusch et al, 1997, Geisser et al, 2008). Thus, fibromyalgia and related syndromes might represent biologic amplification of all sensory stimuli gains, and terms such as sensory sensitivity syndrome have been suggested as a unifying pathophysiological theme (Yunus, 2015).…”