Impaired Auditory Information Processing During Acute Migraine: A Magnetoencephalography Study

Does migraine affect central auditory processing abilities?

OBJECTIVE

Migraine is a neurological disease associated with an altered cortical excitability level. Several studies have investigated the relationship between migraine and central auditory processing (CAP), with deficits in CAP being common among migraine patients. However, studies on the factors affecting these CAP changes observed in migraine patients are still few and controversial. This study aims to investigate CAP changes in migraine patients with Duration Pattern Test (DPT) and Frequency Pattern Test (FPT), which have not been used in previous studies.

METHODS

Sixty subjects were divided into two groups and one migraine subgroup: control group, twenty normal healthy subjects, fourty subjects diagnosed with migraine. They were evaluated using the CAP test including DPT and FPT. To identify the variables and possible effects of the variables, a questionnaire describing the characteristics of migraine features was administered to participants with migraine.

RESULTS

No significant difference was found the between the control and study group in CAP tests scores. No significant correlation was found between migraine characteristics and CAP tests scores. Males had significantly higher FPT scores in both ears than females (p<0.05). Significant statistical negative correlation was found between age and FPT scores for both ears and left DPT scores (p<0.05).

CONCLUSION

Although migraine patients generally showed lower CAP ability than the control group, no significant difference was observed between them. This was also valid for subgroups of migraine. However, as age increased in the migraine group, a significant decrease in CAP performance was observed. It was observed that male migraine patients had better CAP ability, especially FPT scores. Migraine may affect performance in CAP depending on gender and age factors.

Localisation of eloquent cortex using magnetoencephalography and its clinical implications

OBJECTIVES

This study aimed to localise the eloquent cortex and measure evoked field (EF) parameters using magnetoencephalography in patients with epilepsy and tumours near the eloquent cortex.

METHODS

A total of 41 patients (26 with drug-refractory epilepsy and 15 with tumours), with a mean age of 33 years, were recruited. Visual evoked field (VEF), auditory evoked field (AEF), sensory evoked field (SSEF), and motor-evoked field (MEF) latencies, amplitudes, and localisation were compared with those of a control population. Subgroup analyses were performed based on lobar involvement. Evoked Field parameters on the affected side were compared with those on the opposite side. The effect of distance from the lesion on nearby and distant evoked fields was evaluated.

RESULTS

AEF and VEF amplitudes and latencies were reduced bilaterally (p < 0.05). Amplitude in the ipsilateral SSEF was reduced by 29.27% and 2.16% in the AEF group compared to the contralateral side (p = 0.02). In patients with temporal lobe lesions, the SSEF amplitude was reduced bilaterally (p < 0.02), and latency was prolonged compared with controls. The MEF amplitude was reduced and latency was prolonged in patients with frontal lobe lesions (p = 0.01). EF displacement was 32%, 57%, 21%, and 16% for AEF, MEF, VEF, and SSEF respectively. Patients in the epilepsy group had distant EF abnormalities.

CONCLUSIONS

EF amplitude was reduced and latency was prolonged in the involved hemisphere. Distant EF amplitudes were more affected than latencies in epilepsy. Amplitude and distance from the lesion had negative correlation for all EF. EF changes indicated eloquent cortical displacement which may not be apparent on MRI.

Altered amygdala effective connectivity in migraine without aura: evidence from resting-state fMRI with Granger causality analysis

BACKGROUND

Granger causality analysis (GCA) has been used to investigate the pathophysiology of migraine. Amygdala plays a key role in pain modulation of migraine attack. However, the detailed neuromechanism remained to be elucidated. We applied GCA to explore the amygdala-based directional effective connectivity in migraine without aura (MwoA) and to determine the relation with clinical characteristics.

METHODS

Forty-five MwoA patients and forty age-, sex-, and years of education-matched healthy controls(HCs) underwent resting-state functional magnetic resonance imaging (fMRI). Bilateral amygdala were used as seed regions in GCA to investigate directional effective connectivity and relation with migraine duration or attack frequency.

RESULTS

MwoA patients showed significantly decreased effective connectivity from right amygdala to right superior temporal gyrus, left superior temporal gyrus and right precentral gyrus compared with HCs. Furthermore, MwoA patients demonstrated significantly decreased effective connectivity from the left amygdala to the ipsilateral superior temporal gyrus. Also, MwoA patients showed enhanced effective connectivity from left inferior frontal gyrus to left amygdala. Effective connectivity outflow from right amygdala to right precentral gyrus was negatively correlated to disease duration.

CONCLUSIONS

Altered directional effective connectivity of amygdala demonstrated that neurolimbic pain networks contribute to multisensory integration abnormalities and deficits in pain modulation of MwoA patients.

Auditory attention alterations in migraine: A behavioral and MEG/EEG study

OBJECTIVES

To evaluate alterations of top-down and/or bottom-up attention in migraine and their cortical underpinnings.

METHODS

19 migraineurs between attacks and 19 matched control participants performed a task evaluating jointly top-down and bottom-up attention, using visually-cued target sounds and unexpected task-irrelevant distracting sounds. Behavioral responses and magneto- and electro-encephalography signals were recorded. Event-related potentials and fields were processed and source reconstruction was applied to event-related fields.

RESULTS

At the behavioral level, neither top-down nor bottom-up attentional processes appeared to be altered in migraine. However, migraineurs presented heightened evoked responses following distracting sounds (orienting component of the N1 and Re-Orienting Negativity, RON) and following target sounds (orienting component of the N1), concomitant to an increased recruitment of the right temporo-parietal junction. They also displayed an increased effect of the cue informational value on target processing resulting in the elicitation of a negative difference (Nd).

CONCLUSIONS

Migraineurs appear to display increased bottom-up orienting response to all incoming sounds, and an enhanced recruitment of top-down attention.

SIGNIFICANCE

The interictal state in migraine is characterized by an exacerbation of the orienting response to attended and unattended sounds. These attentional alterations might participate to the peculiar vulnerability of the migraine brain to all incoming stimuli.

A Brain Signature to Differentiate Acute and Chronic Pain in Rats

The transition from acute pain to chronic pain entails considerable changes of patients at multiple levels of the nervous system and in psychological states. An accurate differentiation between acute and chronic pain is essential in pain management as it may help optimize analgesic treatments according to the pain state of patients. Given that acute and chronic pain could modulate brain states in different ways and that brain states could greatly shape the neural processing of external inputs, we hypothesized that acute and chronic pain would show differential effects on cortical responses to non-nociceptive sensory information. Here by analyzing auditory-evoked potentials (AEPs) to pure tones in rats with acute or chronic pain, we found opposite influences of acute and chronic pain on cortical responses to auditory inputs. In particular, compared to no-pain controls, the N100 wave of rat AEPs was significantly enhanced in rats with acute pain but significantly reduced in rats with chronic pain, indicating that acute pain facilitated cortical processing of auditory information while chronic pain exerted an inhibitory effect. These findings could be justified by the fact that individuals suffering from acute or chronic pain would have different vigilance states, i.e., the vigilance level to external sensory stimuli would be increased with acute pain, but decreased with chronic pain. Therefore, this auditory response holds promise of being a brain signature to differentiate acute and chronic pain. Instead of investigating the pain system per se, the study of pain-induced influences on cortical processing of non-nocicpetive sensory information might represent a potential strategy to monitor the progress of pain chronification in clinical applications.

Multi-frequency analysis of brain connectivity networks in migraineurs: a magnetoencephalography study

Background

Although alterations in resting-state neural network have been previously reported in migraine using functional MRI, whether this atypical neural network is frequency dependent remains unknown. The aim of this study was to investigate the alterations of the functional connectivity of neural network and their frequency specificity in migraineurs as compared with healthy controls by using magnetoencephalography (MEG) and concepts from graph theory.

Methods

Twenty-three episodic migraine patients with and without aura, during the interictal period, and 23 age- and gender-matched healthy controls at resting state with eye-closed were studied with MEG. Functional connectivity of neural network from low (0.1–1 Hz) to high (80–250 Hz) frequency ranges was analyzed with topographic patterns and quantified with graph theory.

Results

The topographic patterns of neural network showed that the migraineurs had significantly increased functional connectivity in the slow wave (0.1–1 Hz) band in the frontal area as compared with controls. Compared with the migraineurs without aura (MwoA), the migraineurs with aura (MwA) had significantly increased functional connectivity in the theta (4–8 Hz) band in the occipital area. Graph theory analysis revealed that the migraineurs had significantly increased connection strength in the slow wave (0.1–1 Hz) band, increased path length in the theta (4–8 Hz) and ripple (80–250 Hz) bands, and increased clustering coefficient in the slow wave (0.1–1 Hz) and theta (4–8 Hz) bands. The clinical characteristics had no significant correlation with interictal MEG parameters.

Conclusions

Results indicate that functional connectivity of neural network in migraine is significantly impaired in both low- and high-frequency ranges. The alteration of neural network may imply that migraine is associated with functional brain reorganization.

Spatial Heterogeneity of Cortical Excitability in Migraine Revealed by Multifrequency Neuromagnetic Signals

To investigate the spatial heterogeneity of cortical excitability in adolescents with migraine, magnetoencephalography (MEG) recordings at a sampling rate of 6,000 Hz were obtained from 35 adolescents with an acute migraine and 35 age- and sex-matched healthy control participants during an auditory-motor task. Neuromagnetic activation from low- to high-frequency ranges (5-1,000 Hz) was measured at sensor and source levels. The heterogeneity of cortical excitability was quantified within each functional modality (auditory vs motor) and hemispherical lateralization. MEG data showed that high-frequency, not low-frequency neuromagnetic signals, showed heterogeneous cortical activation in migraine subjects compared with control participants (P < .001). The alteration of the heterogeneity of cortical excitability in migraine subjects was independent of age and sex. The degree of the neuromagnetic heterogeneity of cortical activation was significantly correlated with headache frequency (r = .71, P < .005). The alteration of cortical excitability in migraine subjects was spatially heterogeneous and frequency dependent, which previously has not been reported. The finding may be critical for developing spatially targeted therapeutic strategies for normalizing cortical excitability with the purpose of reducing headache attacks.

PERSPECTIVE

This article presents a new approach to quantitatively measure the spatial heterogeneity of cortical excitability in adolescents with migraine using MEG signals in a frequency range of 5 to 1,000 Hz. The characteristics of the location and degree of cortical excitability may be critical for spatially targeted treatment for migraine.

Physical Feature Encoding and Word Recognition Abilities Are Altered in Children with Intractable Epilepsy: Preliminary Neuromagnetic Evidence

Objective evaluation of language function is critical for children with intractable epilepsy under consideration for epilepsy surgery. The purpose of this preliminary study was to evaluate word recognition in children with intractable epilepsy by using magnetoencephalography (MEG). Ten children with intractable epilepsy (M/F 6/4, mean ± SD 13.4 ± 2.2 years) were matched on age and sex to healthy controls. Common nouns were presented simultaneously from visual and auditory sensory inputs in "match" and "mismatch" conditions. Neuromagnetic responses M1, M2, M3, M4, and M5 with latencies of ~100 ms, ~150 ms, ~250 ms, ~350 ms, and ~450 ms, respectively, elicited during the "match" condition were identified. Compared to healthy children, epilepsy patients had both significantly delayed latency of the M1 and reduced amplitudes of M3 and M5 responses. These results provide neurophysiologic evidence of altered word recognition in children with intractable epilepsy.

Resting state brain activity in patients with migraine: a magnetoencephalography study

Background

Recent advances in migraine research have shown that the cerebral cortex serves a primary role in the pathogenesis of migraine. Since aberrant brain activity in migraine can be noninvasively detected with magnetoencephalography (MEG), The object of this study was to investigate the resting state cortical activity differences between migraineurs and controls and its related clinical characteristics.

Methods

Twenty-two subjects with an acute migraine and twenty-two age- and gender-matched controls were studied using MEG. MEG recordings were recorded 120 seconds during the headache attack. Analyze MEG signals from low (1–4 Hz) to high (200–1000 Hz)-frequency ranges.

Results

In comparison with the controls, brain activity in migraine subjects was significantly different from that of the controls both in two frequency ranges (55–90 Hz, p < 0.001) and (90–200 Hz, p < 0.004). But the power value showed no significantly differences between control and migraines in all frequency ranges (p > 0.05). All the clinical characteristics had no significant correlation with aberrant brain activity.

Conclusions

The results demonstrated that migraine subjects in resting state had significantly aberrant ictal brain activity that can be measured with neuromagnetic imaging techniques. The findings may facilitate the development of new therapeutic strategies in migraine treatment via alterations in cortical excitability with TMS and other medications in the future.

Central auditory processing and migraine: a controlled study

Background

This study aimed to verify and compare central auditory processing (CAP) performance in migraine with and without aura patients and healthy controls.

Methods

Forty-one volunteers of both genders, aged between 18 and 40 years, diagnosed with migraine with and without aura by the criteria of “The International Classification of Headache Disorders” (ICDH-3 beta) and a control group of the same age range and with no headache history, were included. Gaps-in-noise (GIN), Duration Pattern test (DPT) and Dichotic Digits Test (DDT) tests were used to assess central auditory processing performance.

Results

The volunteers were divided into 3 groups: Migraine with aura (11), migraine without aura (15), and control group (15), matched by age and schooling. Subjects with aura and without aura performed significantly worse in GIN test for right ear (p = .006), for left ear (p = .005) and for DPT test (p < .001) when compared with controls without headache, however no significant differences were found in the DDT test for the right ear (p = .362) and for the left ear (p = .190).

Conclusions

Subjects with migraine performed worsened in auditory gap detection, in the discrimination of short and long duration. They also presented impairment in the physiological mechanism of temporal processing, especially in temporal resolution and temporal ordering when compared with controls. Migraine could be related to an impaired central auditory processing.

Clinical trial registration

Research Ethics Committee (CEP 0480.10) – UNIFESP

Neuromagnetic abnormality of motor cortical activation and phases of headache attacks in childhood migraine

The cerebral cortex serves a primary role in the pathogenesis of migraine. This aberrant brain activation in migraine can be noninvasively detected with magnetoencephalography (MEG). The objective of this study was to investigate the differences in motor cortical activation between attacks (ictal) and pain free intervals (interictal) in children and adolescents with migraine using both low- and high-frequency neuromagnetic signals. Thirty subjects with an acute migraine and 30 subjects with a history of migraine, while pain free, were compared to age- and gender-matched controls using MEG. Motor cortical activation was elicited by a standardized, validated finger-tapping task. Low-frequency brain activation (1∼50 Hz) was analyzed with waveform measurements and high-frequency oscillations (65–150 Hz) were analyzed with wavelet-based beamforming. MEG waveforms showed that the ictal latency of low-frequency brain activation was significantly delayed as compared with controls, while the interictal latency of brain activation was similar to that of controls. The ictal amplitude of low-frequency brain activation was significantly increased as compared with controls, while the interictal amplitude of brain activation was similar to that of controls. The ictal source power of high-frequency oscillations was significantly stronger than that of the controls, while the interictal source power of high-frequency oscillations was significantly weaker than that of controls. The results suggest that aberrant low-frequency brain activation in migraine during a headache attack returned to normal interictally. However, high-frequency oscillations changed from ictal hyper-activation to interictal hypo-activation. Noninvasive assessment of cortical abnormality in migraine with MEG opens a new window for developing novel therapeutic strategies for childhood migraine by maintaining a balanced cortical excitability.

A preliminary study on the relationship between central auditory processing and childhood primary headaches in the intercritical phase

BACKGROUND

Recently, an increasing number of articles have appeared on central auditory processing disorders, but in the literature there is only one study that evaluated the possible correlation between migraine in the critical phase and central auditory processing. The aim of our study was to assess the correlation between auditory processing information and childhood primary headaches in the intercritical phase.

METHODS

This is an observational study. We enrolled 54 patients, 30 with primary headache (migraine and tension headache) and 24 normal controls, matched for sex and age. The mean age at first observation was 9 years 10 months; the duration of observational follow-up was 2 years. Both groups had normal audiological and neurological profiles, normal peripheral hearing acuity and normal cognitive and behavioral skills. We excluded patients who had undergone pharmacological prophylactic treatment for headaches in the 6 months preceding the study and subjects with a frequency of headache lower than one every two months. After enrolment, both groups were analyzed with a computerized test battery for Speech Perception Tests in silence and in noise background to assess speech perception disabilities. In addition, with a test battery of Speech Perception Tests, we compared patients with migraines and tension-type headaches. The non-parametric χ2 test, the Mann-Whitney U-test and the Wilcoxon signed ranks test were used for statistical analysis. P-values <0.05 were considered significant and STATA 10 software was used for statistical analyses.

RESULTS

Our results showed that patients with primary headache (migraine and tension-type headache), had a deficit of auditory processing in noisy background compared to control cases, but we found no significant differences when we compared patients with migraine and tension-type headache.

CONCLUSIONS

This is a work in progress and further studies are needed to assess the relationship between the impairment of auditory processing and primary headache, not only to improve the diagnostic approach to primary headache, but also to improve therapeutic intervention.

Altered cortical activation in adolescents with acute migraine: a magnetoencephalography study

To quantitatively assess cortical dysfunction in pediatric migraine, 31 adolescents with acute migraine and age- and gender-matched controls were studied using a magnetoencephalography (MEG) system at a sampling rate of 6,000 Hz. Neuromagnetic brain activation was elicited by a finger-tapping task. The spectral and spatial signatures of magnetoencephalography data in 5 to 2,884 Hz were analyzed using Morlet wavelet and beamformers. Compared with controls, 31 migraine subjects during their headache attack phases (ictal) showed significantly prolonged latencies of neuromagnetic activation in 5 to 30 Hz, increased spectral power in 100 to 200 Hz, and a higher likelihood of neuromagnetic activation in the supplementary motor area, the occipital and ipsilateral sensorimotor cortices, in 2,200 to 2,800 Hz. Of the 31 migraine subjects, 16 migraine subjects during their headache-free phases (interictal) showed that there were no significant differences between interictal and control MEG data except that interictal spectral power in 100 to 200 Hz was significantly decreased. The results demonstrated that migraine subjects had significantly aberrant ictal brain activation, which can normalize interictally. The spread of abnormal ictal brain activation in both low- and high-frequency ranges triggered by movements may play a key role in the cascade of migraine attacks.

PERSPECTIVE

This is the first study focusing on the spectral and spatial signatures of cortical dysfunction in adolescents with migraine using MEG signals in a frequency range of 5 to 2,884 Hz. This methodology analyzing aberrant brain activation may be important for developing new therapeutic interventions for migraine in the future.

Magnetoencephalography reveals altered auditory information processing in youth with obsessive-compulsive disorder

Patients with obsessive-compulsive disorder (OCD) often report sensory intolerances which may lead to significant functional impairment. This study used auditory evoked fields (AEFs) to address the question of whether neural correlates of sensory auditory information processing differ in youth with OCD compared with healthy comparison subjects (HCS). AEFs, recorded with a whole head 275-channel magnetoencephalography system, were elicited in response to binaural auditory stimuli from 10 pediatric subjects with OCD (ages 8-13, mean 11 years, 6 males) and 10 age- and gender-matched HCS. Three major neuromagnetic responses were studied: M70 (60-80 ms), M100 (90-120 ms), and M150 (130-190 ms). When compared with HCS, subjects with OCD demonstrated delayed latency of the M100 response. In subjects with OCD the amplitude of the M100 and M150 responses was significantly greater in the right hemisphere compared with the left hemisphere. Current results suggest that when compared with HCS, subjects with OCD have altered auditory information processing, evident from the delayed latency of the M100 response, which is thought to be associated with the encoding of physical stimulus characteristics. Interhemispheric asymmetry with increased M100 and M150 amplitudes over the right hemisphere compared with the left hemisphere was found in young OCD subjects. These results should be interpreted with caution due to the high variability rate of responses in both HCS and OCD subjects, as well as the possible effect of medication in OCD subjects.

Aberrant neuromagnetic activation in the motor cortex in children with acute migraine: a magnetoencephalography study

Migraine attacks have been shown to interfere with normal function in the brain such as motor or sensory function. However, to date, there has been no clinical neurophysiology study focusing on the motor function in children with migraine during headache attacks. To investigate the motor function in children with migraine, twenty-six children with acute migraine, meeting International Classification of Headache Disorders criteria and age- and gender-matched healthy children were studied using a 275-channel magnetoencephalography system. A finger-tapping paradigm was designed to elicit neuromagnetic activation in the motor cortex. Children with migraine showed significantly prolonged latency of movement-evoked magnetic fields (MEF) during finger movement compared with the controls. The correlation coefficient of MEF latency and age in children with migraine was significantly different from that in healthy controls. The spectral power of high gamma (65–150 Hz) oscillations during finger movement in the primary motor cortex is also significantly higher in children with migraine than in controls. The alteration of responding latency and aberrant high gamma oscillations suggest that the developmental trajectory of motor function in children with migraine is impaired during migraine attacks and/or developmentally delayed. This finding indicates that childhood migraine may affect the development of brain function and result in long-term problems.

Pediatric headache: update on recent research

Primary headache are one of the most common health complaints in children and adolescents, yet there remain significant gaps in our understanding of the underlying pathophysiology of these conditions. Recently, there have been several areas of research that have assisted with filling this gap in our knowledge. These areas include a better understanding of the disease characteristics including additional associated symptoms and the refinement of the description of related conditions and comorbidities; continued examination of the epidemiology of primary headaches; the progression of migraine across these developmental ages; the molecular and physiological changes; and the potential role for vitamins and cofactor deficiencies in the pathophysiology. These studies continue to add to our fund of knowledge on the basis of migraine and tension-type headache as primary neurological conditions and their impact on the developing brain.

The mismatch negativity (MMN)--a unique window to disturbed central auditory processing in ageing and different clinical conditions

In this article, we review clinical research using the mismatch negativity (MMN), a change-detection response of the brain elicited even in the absence of attention or behavioural task. In these studies, the MMN was usually elicited by employing occasional frequency, duration or speech-sound changes in repetitive background stimulation while the patient was reading or watching videos. It was found that in a large number of different neuropsychiatric, neurological and neurodevelopmental disorders, as well as in normal ageing, the MMN amplitude was attenuated and peak latency prolonged. Besides indexing decreased discrimination accuracy, these effects may also reflect, depending on the specific stimulus paradigm used, decreased sensory-memory duration, abnormal perception or attention control or, most importantly, cognitive decline. In fact, MMN deficiency appears to index cognitive decline irrespective of the specific symptomatologies and aetiologies of the different disorders involved.