Intensity dependence of auditory-evoked cortical potentials in fibromyalgia patients: a test of the generalized hypervigilance hypothesis.

Departamento de Psicología Clínica y Psicobiología, Universidad de Santiago de Compostela, Santiago de Compostela, Spain.
Journal of Pain (Impact Factor: 4.22). 08/2006; 7(7):480-7. DOI: 10.1016/j.jpain.2006.01.452
Source: PubMed

ABSTRACT On the basis of recent evidence concerning the amplification of incoming stimulation in fibromyalgia (FM) patients, it has been proposed that a generalized hypervigilance of painful and nonpainful sensations may be at the root of this disorder. So far, research into this issue has been inconclusive, possibly owing to the lack of agreement as to the operational definition of "generalized hypervigilance" and to the lack of robust objective measures characterizing the sensory style of FM patients. In this study, we recorded auditory-evoked potentials (AEPs) elicited by tones of increasing intensity (60, 70, 80, 90, and 105 dB) in 27 female FM patients and 25 healthy controls. Fibromyalgia patients presented shorter N1 and P2 latencies and a stronger intensity dependence of their AEPs. Both results suggest that FM patients may be hypervigilant to sensory stimuli, especially when very loud tones are used. The most noteworthy difference between patients and control subjects is at the highest stimulus intensity, for which far more patients maintained increased N1-P2 amplitudes in relation to the 90-dB tones. The larger AEP amplitudes to the 105-dB tones suggest that defects in an inhibitory system protecting against overstimulation may be a crucial factor in the pathophysiology of FM. Because a stronger loudness dependence of AEPs has been related to weak serotonergic transmission, it is hypothesized that for many FM patients deficient inhibition of the response to noxious and intense auditory stimuli may be due to a serotonergic deficit. PERSPECTIVE: The study of auditory-evoked potentials in response to tones of increasing intensity in FM patients may help to clarify the pathophysiology of this disorder, especially regarding the role of inhibition deficits involving serotonergic dysfunction, and may be a useful tool to guide the pharmacologic treatment of FM patients.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The heterogeneity found in fibromyalgia (FM) patients has led to the investigation of disease subgroups, mainly based on clinical features. The aim of this study was to test the hypothesis that clinical FM subgroups are associated with different underlying pathophysiological mechanisms. Sixty-three FM patients were classified in type I or type II, according to the Fibromyalgia Impact Questionnaire (FIQ), and in mild/moderate versus severe FM, according to the severity of three cardinal symptoms considered in the American College of Rheumatology (ACR) 2010 criteria (unrefreshed sleep, cognitive problems and fatigue). To validate the subgroups obtained by these two classifications, we calculated the area under the receiver operating characteristic curves for various clinical variables and for two potential biomarkers of FM: Response to experimental pressure pain (algometry) and the amplitude/intensity slopes of the auditory evoked potentials (AEPs) obtained to stimuli of increasing intensity. The variables that best discriminated type I versus type II were those related to depression, while the indices of clinical or experimental pain (threshold or tolerance) did not significantly differ between them. The variables that best discriminated the mild/moderate versus severe subgroups were those related to the algometry. The AEPs did not allow discrimination among the generated subsets. The FIQ-based classification allows the identification of subgroups that differ in psychological distress, while the index based on the ACR 2010 criteria seems to be useful to characterize the severity of FM mainly based on hyperalgesia. The incorporation of potential biomarkers to generate or validate classification criteria is crucial to advance in the knowledge of FM and in the understanding of pathophysiological pathways.
    Rheumatology International 04/2014; 34(11). · 1.63 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Evidence coming from neuropsychological studies has showed the presence of cognitive alterations in Fibromyalgia. Such dysfunctions are specially remarkable when the set in motion of executive control processes, such as inhibition, is required to perform successfully; however, neural data related to these mechanisms are very scarce. Present study tried to characterize cognitive inhibition mechanisms, as part of the attentional control functions, in patients with Fibromyalgia. Participants (two groups: Fibromyalgia patients and healthy controls participants) were asked to perform in an emotional Stroop task while event-related potentials (ERP) were recorded. Four different emotional interference conditions were created: Fibromyalgia symptom-related words, arousing-negative, arousing-positive and neutral words. Brain activity and behavioural data were analysed. Principal components analyses were employed to reliably define ERP components along with a source-estimation technique. Symptom-related words elicited greater frontal P450 amplitudes and enhanced activation within right inferior frontal gyrus as compared to rest of stimuli. This effect was only true for the Fibromyalgia group. Behavioural contrasts, however, did not produce significant differences. Scalp and source estimation findings suggest the presence of a specific difficulty in cognitive inhibition in Fibromyalgia patients (under conditions intimately linked with the core concerns of their disease). Data point to the involvement of right inferior frontal cortices in this inefficient mechanism, which might cause an enhanced and dysfunctional effort of processing to achieve only a comparable performance to healthy people. Implications of these results are discussed. Nevertheless, further investigations are needed to better understand dysfunctional cognition in Fibromyalgia.
    International journal of psychophysiology: official journal of the International Organization of Psychophysiology 04/2013; · 3.05 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Augmenting/reducing is a personality dimension related to the processing of sensory stimuli. Augmenters are assumed to augment the impact of stimuli leading to stimulation-avoidant behavior and lower pain tolerance. Reducers are assumed to attenuate sensory stimuli leading to stimulation-seeking behavior and higher pain tolerance. Augmenting/reducing can be assessed by the method of evoked potentials or - as in this study - by questionnaire. Two studies were conducted to examine associations between augmenting/ reducing as assessed by questionnaire and stimulus intensity modulation. Study 1 found reducers (n = 24, 12 females) to more frequently consume psychoactive substances and to turn music on louder than augmenters (n = 25, 12 females) even after controlling for individual hearing ability. In Study 2, reducers (n = 19, 10 females) were more pain tolerant than augmenters (n = 18, 9 females) and this difference increased with increasing stimulation time. Moreover, reducers were faster than augmenters in a rapid tapping task but there was no difference in a lower-stimulation tracking task. The results suggest that differences between augmenters and reducers are most reliable when the stimulation potential is high. The clinical relevance of this construct is discussed. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
    Journal of Individual Differences 01/2007; 28(3):165-177. · 0.83 Impact Factor

Full-text (2 Sources)

Available from
May 15, 2014