The aim of this study was to assess the ability of multiscale sample entropy (MSE), refined composite multiscale entropy (RCMSE), and complexity index (CI) to characterize gait complexity through trunk acceleration patterns in subjects with Parkinson’s disease (swPD) and healthy subjects, regardless of age or gait speed. The trunk acceleration patterns of 51 swPD and 50 healthy subjects (HS) were acquired using a lumbar-mounted magneto-inertial measurement unit during their walking. MSE, RCMSE, and CI were calculated on 2000 data points, using scale factors (τ) 1–6. Differences between swPD and HS were calculated at each τ, and the area under the receiver operating characteristics, optimal cutoff points, post-test probabilities, and diagnostic odds ratios were calculated. MSE, RCMSE, and CIs showed to differentiate swPD from HS. MSE in the anteroposterior direction at τ4 and τ5, and MSE in the ML direction at τ4 showed to characterize the gait disorders of swPD with the best trade-off between positive and negative posttest probabilities and correlated with the motor disability, pelvic kinematics, and stance phase. Using a time series of 2000 data points, a scale factor of 4 or 5 in the MSE procedure can yield the best trade-off in terms of post-test probabilities when compared to other scale factors for detecting gait variability and complexity in swPD.

Background: The cyclical brain disorder of sensory processing accompanying migraine phases lacks an explanatory unified theory. Methods: We searched Pubmed for non-invasive neurophysiological studies on migraine and related conditions using transcranial magnetic stimulation, electroencephalography, visual and somatosensory evoked potentials. We summarized the literature, reviewed methods, and proposed a unified theory for the pathophysiology of electrophysiological abnormalities underlying migraine recurrence. Results: All electrophysiological modalities have determined specific changes in brain dynamics across the different phases of the migraine cycle. Transcranial magnetic stimulation studies show unbalanced recruitment of inhibitory and excitatory circuits, more consistently in aura, which ultimately results in a substantially distorted response to neuromodulation protocols. Electroencephalography investigations highlight a steady pattern of reduced alpha and increased slow rhythms, largely located in posterior brain regions, which tends to normalize closer to the attacks. Finally, non-painful evoked potentials suggest dysfunctions in habituation mechanisms of sensory cortices that revert during ictal phases. Conclusion: Electrophysiology shows dynamic and recurrent functional alterations within the brainstem-thalamus-cortex loop varies continuously and recurrently in migraineurs. Given the central role of these structures in the selection, elaboration, and learning of sensory information, these functional alterations suggest chronic, probably genetically determined dysfunctions of the synaptic short- and long-term learning mechanisms.

Purpose of Review: We reviewed the literature that explored the use of central and peripheral neuromodulation techniques for chronic daily headache (CDH) treatment. Recent Findings: Although the more invasive deep brain stimulation (DBS) is effective in chronic cluster headache (CCH), it should be reserved for extremely difficult-to-treat patients. Percutaneous occipital nerve stimulation has shown similar efficacy to DBS and is less risky in both CCH and chronic migraine (CM). Non-invasive transcutaneous vagus nerve stimulation is a promising add-on treatment for CCH but not for CM. Transcutaneous external trigeminal nerve stimulation may be effective in treating CM; however, it has not yet been tested for cluster headache. Transcranial magnetic and electric stimulations have promising preventive effects against CM and CCH. Summary: Although the precise mode of action of non-invasive neuromodulation techniques remains largely unknown and there is a paucity of controlled trials, they should be preferred to more invasive techniques for treating CDH.

Background: Despite advances in neuroimaging and electrophysiology, cluster headache’s pathogenesis remains unclear. This review will examine clinical neurophysiology studies, including electrophysiological and functional neuroimaging, to determine if they might help us construct a neurophysiological model of cluster headache. Results: Clinical, biochemical, and electrophysiological research have implicated the trigeminal-parasympathetic system in cluster headache pain generation, although the order in which these two systems are activated, which may be somewhat independent, is unknown. Electrophysiology and neuroimaging have found one or more central factors that may cause seasonal and circadian attacks. The well-known posterior hypothalamus, with its primary circadian pacemaker suprachiasmatic nucleus, the brainstem monoaminergic systems, the midbrain, with an emphasis on the dopaminergic system, especially when cluster headache is chronic, and the descending pain control systems appear to be involved. Functional connection investigations have verified electrophysiological evidence of functional changes in distant brain regions connecting to wide cerebral networks other than pain. Conclusion: We propose that under the impact of external time, an inherited misalignment between the primary circadian pacemaker suprachiasmatic nucleus and other secondary extra- suprachiasmatic nucleus clocks may promote disturbance of the body’s internal physiological clock, lowering the threshold for bout recurrence.

Background: Focusing on calcitonin gene-related peptide (CGRP) as a specific target has changed and improved migraine management. After the positive results of monoclonal antibodies directed to the CGRP pathway (anti-CGRP mAbs), randomized controlled trials also demonstrated the efficacy of gepants in migraine prevention. The present study aimed to assess the effectiveness of atogepant in preventing migraine after a 12-week treatment in clinical practice. Methods: Adult patients with a clinical indication for atogepant 60 mg daily were screened for participation in this multicentric prospective observational cohort study. At baseline (T0) and after 12 weeks (T3) since the first atogepant administration, monthly migraine days (MMDs), monthly headache days (MHDs) and monthly acute medications (MAMs) were assessed. The co-primary endpoints were the changes in MMDs from T0 to T3 and the percentage of T3 Responders (those with a reduction of MMDs ≥50%, i.e. 50% response rate (RR)). At T0 and T3, we also collected the Headache Impact Test (HIT-6), the Migraine Disability Assessment (MIDAS) questionnaire, the Migraine Treatment Optimization Questionnaire-6 (mTOQ-6), the Migraine-Specific Quality-of-Life Questionnaire (MSQ), the 12-item Allodynia Symptom Checklist (ASC-12) and the Migraine Interictal Burden Scale (MIBS-4). Results: One hundred and six patients (56/106 (52.8%) with chronic migraine (CM), 93/106 (87.7%) female, aged 50.6 ± 13.2 years) from 10 Italian centers completed the 12-week observation since the first atogepant tablet intake. From baseline to T3, a reduction of 6.9 MMDs (SD 9.7; p < 0.001) was achieved in the whole group and, specifically, of −4.9 (SD 6.6; p < 0.001) in episodic migraine (EM) and of −8.6 (SD 11.7; p < 0.001) in CM patients. Overall, 60/106 (56.6%) of patients were Responders (60.0% in the EM and 46.4% in the CM group). Non-Responders previously experienced more ineffective treatments than Responders with anti-CGRP mAbs (65.2% vs. 43.3%, respectively, p = 0.031) and with onabotulinumtoxinA (56.5% vs. 28.3%, p = 0.005), and presented more medication overuse at baseline (55.7% vs. 44.3%, p = 0.003). However, no baseline characteristics were significantly associated with the Responder status in the multiple regression analysis. For T0 to T3, MAMs, MIDAS, ASC-12 and mTOQ-6 reduced ( p ≤ 0.001 consistently), and MSQ role-function restriction increased ( p = 0.026), whereas HIT-6 and MIBS-4 did not change. Only seven subjects (7/106, 6.6%) dropped out of atogepant treatment: four for lack of effectiveness and three for adverse events or poor tolerability. Conclusions: The STAR study demonstrates the effectiveness and tolerability of atogepant 60 mg at 12 weeks in a real-world setting. Previous ineffective anti-CGRP mAbs were not a relevant prognostic factor. Trial Registration: The study was preregistered on clinicaltrial.gov, NCT06414044.

Background: The prodrome or premonitory phase is the initial phase of a migraine attack, and it is considered as a symptomatic phase in which prodromal symptoms may occur. There is evidence that attacks start 24–48 hours before the headache phase. Individuals with migraine also report several potential triggers for their attacks, which may be mistaken for premonitory symptoms and hinder migraine research. Methods: This review aims to summarize published studies that describe contributions to understanding the fine difference between prodromal/premonitory symptoms and triggers, give insights for research, and propose a way forward to study these phenomena. We finally aim to formulate a theory to unify migraine triggers and prodromal symptoms. For this purpose, a comprehensive narrative review of the published literature on clinical, neurophysiological and imaging evidence on migraine prodromal symptoms and triggers was conducted using the PubMed database. Results: Brain activity and network connectivity changes occur during the prodromal phase. These changes give rise to prodromal/premonitory symptoms in some individuals, which may be falsely interpreted as triggers at the same time as representing the early manifestation of the beginning of the attack. By contrast, certain migraine triggers, such as stress, hormone changes or sleep deprivation, acting as a catalyst in reducing the migraine threshold, might facilitate these changes and increase the chances of a migraine attack. Migraine triggers and prodromal/premonitory symptoms can be confused and have an intertwined relationship with the hypothalamus as the central hub for integrating external and internal body signals. Conclusions: Differentiating migraine triggers and prodromal symptoms is crucial for shedding light on migraine pathophysiology and improve migraine management.