Pick Topic
Review Topic
List Experts
Examine Expert
Save Expert
  Site Guide ··   
Migraine Disorders: HELP
Articles from British Columbia
Based on 28 articles published since 2009

These are the 28 published articles about Migraine Disorders that originated from British Columbia during 2009-2019.
+ Citations + Abstracts
Pages: 1 · 2
1 Editorial Botulinum neurotoxin A for chronic migraine headaches: does it work and how? 2014

Cairns, Brian E / Gazerani, Parisa. ·Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, V6T 1Z3, Canada. ·Pain Manag · Pubmed #25494688.

ABSTRACT: -- No abstract --

2 Review Dysautonomia in the pathogenesis of migraine. 2018

Gazerani, Parisa / Cairns, Brian Edwin. ·a Department of Health Science and Technology, Faculty of Medicine , Aalborg University , Aalborg , Denmark. · b Faculty of Pharmaceutical Sciences , The University of British Columbia , Vancouver , BC , Canada. ·Expert Rev Neurother · Pubmed #29212396.

ABSTRACT: INTRODUCTION: Migraine is a common complex neurological disorder involving multiple brain areas that regulate autonomic, affective, cognitive, and sensory functions. This review explores autonomic nervous system (ANS) dysfunction in migraine headache sufferers. Areas covered: Reference material for this review was obtained through PubMed searches. Migraine attacks can present with up to 4 phases (premonitory, aura, headache, postdrome) each with distinguishable signs and symptoms. Altered ANS tone can be found from the premonitory through the postdrome phases. Features of the migraine attack that are indicative of altered autonomic function, which include nausea, vomiting, diarrhea, polyuria, eyelid edema, conjunctival injection, lacrimation, nasal congestion, and ptosis, are discussed and putative mechanisms explored. In addition, alteration of ANS function by endogenous and exogenous stressors, such as bright lights, hunger, poor sleep quality, menses, and special dietary components is discussed. The influence of currently employed pharmacological treatments on altered autonomic function during the migraine attack is explored. Expert commentary: Migraine-related alterations in ANS function have a complex pattern, but, in general, an imbalance occurs between sympathetic and parasympathetic tone. Through an improved understanding the role of autonomic changes in pathogenesis of migraine, it may be possible to develop even more effective treatments for migraine sufferers.

3 Review Comparative tolerability of treatments for acute migraine: A network meta-analysis. 2017

Thorlund, Kristian / Toor, Kabirraaj / Wu, Ping / Chan, Keith / Druyts, Eric / Ramos, Elodie / Bhambri, Rahul / Donnet, Anne / Stark, Richard / Goadsby, Peter J. ·1 Department of Clinical Epidemiology & Biostatistics, McMaster University, Hamilton, Ontario, Canada. · 2 Redwood Outcomes, Vancouver, British Columbia, Canada. · 3 School of Population and Public Health, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada. · 4 Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada. · 5 Pfizer Ltd, New York, New York, USA. · 6 Department of Evaluation and Treatment of Pain, Clinical Neuroscience Federation, La Timone Hospital, Marseille, France. · 7 Neurology Department, Alfred Hospital, Melbourne, Victoria, Australia. · 8 Department of Medicine, Monash University, Melbourne, Victoria, Australia. · 9 NIHR-Wellcome Trust Clinical Research Facility, King's College London, London, UK. ·Cephalalgia · Pubmed #27521843.

ABSTRACT: Introduction Migraine headache is a neurological disorder whose attacks are associated with nausea, vomiting, photophobia and phonophobia. Treatments for migraine aim to either prevent attacks before they have started or relieve attacks (abort) after onset of symptoms and range from complementary therapies to pharmacological interventions. A number of treatment-related adverse events such as somnolence, fatigue, and chest discomfort have previously been reported in association with triptans. The comparative tolerability of available agents for the abortive treatment of migraine attacks has not yet been systematically reviewed and quantified. Methods We performed a systematic literature review and Bayesian network meta-analysis for comparative tolerability of treatments for migraine. The literature search targeted all randomized controlled trials evaluating oral abortive treatments for acute migraine over a range of available doses in adults. The primary outcomes of interest were any adverse event, treatment-related adverse events, and serious adverse events. Secondary outcomes were fatigue, dizziness, chest discomfort, somnolence, nausea, and vomiting. Results Our search yielded 141 trials covering 15 distinct treatments. Of the triptans, sumatriptan, eletriptan, rizatriptan, zolmitriptan, and the combination treatment of sumatriptan and naproxen were associated with a statistically significant increase in odds of any adverse event or a treatment-related adverse event occurring compared with placebo. Of the non-triptans, only acetaminophen was associated with a statistically significant increase in odds of an adverse event occurring when compared with placebo. Overall, triptans were not associated with increased odds of serious adverse events occurring and the same was the case for non-triptans. For the secondary outcomes, with the exception of vomiting, all triptans except for almotriptan and frovatriptan were significantly associated with increased risk for all outcomes. Almotriptan was significantly associated with an increased risk of vomiting, whereas all other triptans yielded non-significant lower odds compared with placebo. Generally, the non-triptans were not associated with decreased tolerability for the secondary outcomes. Discussion In summary, triptans were associated with higher odds of any adverse event or a treatment-related adverse event occurring when compared to placebo and non-triptans. Non-significant results for non-triptans indicate that these treatments are comparable with one another and placebo regarding tolerability outcomes.

4 Review Risk of medication overuse headache across classes of treatments for acute migraine. 2016

Thorlund, Kristian / Sun-Edelstein, Christina / Druyts, Eric / Kanters, Steve / Ebrahim, Shanil / Bhambri, Rahul / Ramos, Elodie / Mills, Edward J / Lanteri-Minet, Michel / Tepper, Stewart. ·Department of Clinical Epidemiology & Biostatistics, McMaster University, Hamilton, ON, Canada. kthorlund@redwoodoutcomes.com. · Redwood Outcomes, 302-1505 2nd Ave. West, Vancouver, BC, Canada. kthorlund@redwoodoutcomes.com. · Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Melbourne, Australia. · Redwood Outcomes, 302-1505 2nd Ave. West, Vancouver, BC, Canada. · Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada. · School of Population and Public Health, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada. · Department of Clinical Epidemiology & Biostatistics, McMaster University, Hamilton, ON, Canada. · Pfizer Ltd, New York, NY, USA. · Pain Department, CHU Nice, France - FHU InovPain, Université Nice Côte d'Azur, Nice, France. · INSERM U1107, Neuo-Dol, Trigeminal Pain and Migraine Université Auvergne, Clermont-Ferrand, France. · Geisel School of Medicine at Dartmouth, Hanover, NH, USA. ·J Headache Pain · Pubmed #27882516.

ABSTRACT: BACKGROUND: The most commonly prescribed medications used to treat migraine acutely are single analgesics, ergots, opioids, and triptans. Due to varying mechanisms of action across drug classes, there is reason to believe that some classes may be less likely than others to elicit Medication Overuse Headache (MOH) than others. We therefore aimed to determine whether certain classes of acute migraine drugs are more likely to elicit MOH than others. METHODS: A comprehensive systematic literature was conducted to identify studies of varying designs that reported on MOH within the considered treatment classes. Only studies that reported MOH according to the International Classification of Headache Disorders (ICHD) were considered. Since no causal comparative design studies were identified; data from prevalence studies and surveys were retrieved. Prevalence-based relative risks between treatment classes were calculated by integrating both medication overuse and medication use from published studies. For each pair wise comparison, pooled relative risks were calculated as the inverse variance weighted average. RESULTS: A total of 29 studies informed the relative risk between treatment classes, all of which reported country-specific data. Five studies reported country-specific medication use data. For triptans versus analgesics the study relative risks generally favored triptans. The pooled relative risk was 0.65 (i.e., relative risk reduction of 35 %). For ergots versus analgesics, a similar trend was observed in favor of ergots with a relative risk of 0.41. For triptans versus ergots, the direction of effect was mixed, and the pooled relative risk was 1.07. Both triptans and ergots appeared favorable when compared to opioids, with pooled relative risks of 0.35 and 0.76, respectively. However, the evidence was limited for these comparisons. Analgesics and opioids also appeared to yield similar risk of MOH (pooled relative risk 1.09). CONCLUSION: Our study suggests that in patients receiving acute migraine treatment, analgesics and opioids are associated with a higher risk of developing MOH compared with other treatments. These findings provide incentive for better monitoring of use of analgesics and opioids for treating acute migraine, and suggest possible clinical preference for use of so-called "migraine-specific" treatments, that is, triptans and ergots.

5 Review Canadian Headache Society systematic review and recommendations on the treatment of migraine pain in emergency settings. 2015

Orr, Serena L / Aubé, Michel / Becker, Werner J / Davenport, W Jeptha / Dilli, Esma / Dodick, David / Giammarco, Rose / Gladstone, Jonathan / Leroux, Elizabeth / Pim, Heather / Dickinson, Garth / Christie, Suzanne N. ·University of Ottawa, Canada Children's Hospital of Eastern Ontario, Canada sorr@cheo.on.ca. · Montreal Neurological Institute, McGill University, Canada. · University of Calgary, Faculty of Medicine, Department of Clinical Neurosciences, Hotchkiss Brain Institute, Canada. · University of Calgary Faculty of Medicine, Departments of Clinical Neurosciences and Medical Genetics, Hotchkiss Brain Institute, Canada. · Department of Medicine, Division of Neurology, University of British Columbia, Canada. · Mayo Clinic College of Medicine, Department of Neurology, AZ, USA. · Associate Clinical Professor Hamilton Health Sciences, St Joseph's Healthcare Hamilton, Canada. · Sunnybrook Health Sciences Centre, The Hospital for Sick Children, University of Toronto, Canada. · Centre Hospitalier Universitaire de Montréal, Canada. · University of Ottawa, Canada. ·Cephalalgia · Pubmed #24875925.

ABSTRACT: BACKGROUND: There is a considerable amount of practice variation in managing migraines in emergency settings, and evidence-based therapies are often not used first line. METHODS: A peer-reviewed search of databases (MEDLINE, Embase, CENTRAL) was carried out to identify randomized and quasi-randomized controlled trials of interventions for acute pain relief in adults presenting with migraine to emergency settings. Where possible, data were pooled into meta-analyses. RESULTS: Two independent reviewers screened 831 titles and abstracts for eligibility. Three independent reviewers subsequently evaluated 120 full text articles for inclusion, of which 44 were included. Individual studies were then assigned a US Preventive Services Task Force quality rating. The GRADE scheme was used to assign a level of evidence and recommendation strength for each intervention. INTERPRETATION: We strongly recommend the use of prochlorperazine based on a high level of evidence, lysine acetylsalicylic acid, metoclopramide and sumatriptan, based on a moderate level of evidence, and ketorolac, based on a low level of evidence. We weakly recommend the use of chlorpromazine based on a moderate level of evidence, and ergotamine, dihydroergotamine, lidocaine intranasal and meperidine, based on a low level of evidence. We found evidence to recommend strongly against the use of dexamethasone, based on a moderate level of evidence, and granisetron, haloperidol and trimethobenzamide based on a low level of evidence. Based on moderate-quality evidence, we recommend weakly against the use of acetaminophen and magnesium sulfate. Based on low-quality evidence, we recommend weakly against the use of diclofenac, droperidol, lidocaine intravenous, lysine clonixinate, morphine, propofol, sodium valproate and tramadol.

6 Review Voltage-gated calcium channels and disease. 2011

Cain, Stuart M / Snutch, Terrance P. ·Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada. ·Biofactors · Pubmed #21698699.

ABSTRACT: Voltage-gated calcium channels are a family of integral membrane calcium-selective proteins found in all excitable and many nonexcitable cells. Calcium influx affects membrane electrical properties by depolarizing cells and generally increasing excitability. Calcium entry further regulates multiple intracellular signaling pathways as well as the biochemical factors that mediate physiological functions such as neurotransmitter release and muscle contraction. Small changes in the biophysical properties or expression of calcium channels can result in pathophysiological changes leading to serious chronic disorders. In humans, mutations in calcium channel genes have been linked to a number of serious neurological, retinal, cardiac, and muscular disorders.

7 Review Migraine and vertigo: a marriage of convenience? 2010

Phillips, John / Longridge, Neil / Mallinson, Arthur / Robinson, Gordon. ·Neurotology Unit, Division of Otolaryngology, University of British Columbia, Vancouver, BC, Canada. ·Headache · Pubmed #20738416.

ABSTRACT: "Migraine associated vertigo" is emerging as a popular diagnosis for patients with recurrent vertigo. However, in view of our current understanding of both migraine and vertigo, "migraine associated vertigo," in contrast to basilar artery migraine, is neither clinically nor biologically plausible as a migraine variant.

8 Article Auditory brainstem function in women with vestibular migraine: a controlled study. 2019

Takeuti, Alice A / Fávero, Mariana L / Zaia, Erica Helena / Ganança, Fernando F. ·Departamento de Otorrinolaringologia e Cirurgia de Cabeça e Pescoço, Universidade Federal de São Paulo, São Paulo, Brazil. a.takeuti@unifesp.br. · Divisão de Educação e Reabilitação dos Distúrbios da Comunicação (DERDIC), Pontíficia Universidade Catolica de São Paulo, São Paulo, Brazil. · Audio-Vestibular Clinic, Vancouver, Canada. · Departamento de Otorrinolaringologia e Cirurgia de Cabeça e Pescoço, Universidade Federal de São Paulo, São Paulo, Brazil. ·BMC Neurol · Pubmed #31248379.

ABSTRACT: BACKGROUND: Vestibular migraine (VM) has been recognized as a diagnostic entity over the past three decades. It affects up to 1% of the general population and 7% of patients seen in dizziness clinics. It is still underdiagnosed; consequently, it is important to conduct clinical studies that address diagnostic indicators of VM. The aim of this study was to assess auditory brainstem function in women with vestibular migraine using electrophysiological testing, contralateral acoustic reflex and loudness discomfort level. METHODS: The study group consisted of 29 women with vestibular migraine in the interictal period, and the control group comprised 25 healthy women. Auditory brainstem response, frequency following response, binaural interaction component and assessment of contralateral efferent suppression were performed. The threshold of loudness discomfort and the contralateral acoustic reflex were also investigated. The results were compared between the groups. RESULTS: There was a statistically significant difference between the groups in the frequency following response and the loudness discomfort level. CONCLUSIONS: The current study suggested that temporal auditory processing and loudness discomfort levels are altered in VM patients during the interictal period, indicating that these measures may be useful as diagnostic criteria.

9 Article Dynamic changes in CGRP, PACAP, and PACAP receptors in the trigeminovascular system of a novel repetitive electrical stimulation rat model: Relevant to migraine. 2019

Zhang, Qing / Han, Xun / Wu, Hangfei / Zhang, Mingjie / Hu, Guanqun / Dong, Zhao / Yu, Shengyuan. ·1 Department of Neurology, Chinese PLA General Hospital, Beijing, China. · 2 Townsend Family Laboratories, Department of Psychiatry, University of British Columbia, Vancouver, British Columbia, Canada. ·Mol Pain · Pubmed #30799680.

ABSTRACT: Migraine is the seventh most disabling disorder globally, with prevalence of 11.7% worldwide. One of the prevailing mechanisms is the activation of the trigeminovascular system, and calcitonin gene-related peptide (CGRP) is an important therapeutic target for migraine in this system. Recent studies suggested an emerging role of pituitary adenylate cyclase-activating peptide (PACAP) in migraine. However, the relation between CGRP and PACAP and the role of PACAP in migraine remain undefined. In this study, we established a novel repetitive (one, three, and seven days) electrical stimulation model by stimulating dura mater in conscious rats. Then, we determined expression patterns in the trigeminal ganglion and the trigeminal nucleus caudalis of the trigeminovascular system. Electrical stimulation decreased facial mechanical thresholds, and the order of sensitivity was as follows: vibrissal pad >inner canthus >outer canthus (P < 0.001). The electrical stimulation group exhibited head-turning and head-flicks (P < 0.05) nociceptive behaviors. Importantly, electrical stimulation increased the expressions of CGRP, PACAP, and the PACAP-preferring type 1 (PAC1) receptor in both trigeminal ganglion and trigeminal nucleus caudalis (P < 0.05). The expressions of two vasoactive intestinal peptide (VIP)-shared type 2 (VPAC1 and VPAC2) receptors were increased in the trigeminal ganglion, whereas in the trigeminal nucleus caudalis, their increases were peaked on Day 3 and then decreased by Day 7. PACAP was colocalized with NEUronal Nuclei (NeuN), PAC1, and CGRP in both trigeminal ganglion and the trigeminal nucleus caudalis. Our results demonstrate that the repetitive electrical stimulation model can simulate the allodynia during the migraine chronification, and PACAP plays a role in the pathogenesis of migraine potentially via PAC1 receptor.

10 Article Patterns of medicinal cannabis use, strain analysis, and substitution effect among patients with migraine, headache, arthritis, and chronic pain in a medicinal cannabis cohort. 2018

Baron, Eric P / Lucas, Philippe / Eades, Joshua / Hogue, Olivia. ·Center for Neurological Restoration - Headache and Chronic Pain Medicine, Department of Neurology, Cleveland Clinic Neurological Institute, 10524 Euclid Avenue, C21, Cleveland, OH, 44195, USA. barone2@ccf.org. · Tilray, 1100 Maughan Rd, Nanaimo, BC, V9X 1J2, Canada. · Social Dimensions of Health, University of Victoria, 3800 Finnerty Rd, Victoria, BC, V8P 5C2, Canada. · Canadian Institute for Substance Use Research, 2300 McKenzie Ave, Victoria, BC, V8N 5M8, Canada. · Section of Biostatistics, Department of Quantitative Health Sciences, Cleveland Clinic Lerner Research Institute, 9500 Euclid Avenue, JJN3, Cleveland, OH, 44195, USA. ·J Headache Pain · Pubmed #29797104.

ABSTRACT: BACKGROUND: Medicinal cannabis registries typically report pain as the most common reason for use. It would be clinically useful to identify patterns of cannabis treatment in migraine and headache, as compared to arthritis and chronic pain, and to analyze preferred cannabis strains, biochemical profiles, and prescription medication substitutions with cannabis. METHODS: Via electronic survey in medicinal cannabis patients with headache, arthritis, and chronic pain, demographics and patterns of cannabis use including methods, frequency, quantity, preferred strains, cannabinoid and terpene profiles, and prescription substitutions were recorded. Cannabis use for migraine among headache patients was assessed via the ID Migraine™ questionnaire, a validated screen used to predict the probability of migraine. RESULTS: Of 2032 patients, 21 illnesses were treated with cannabis. Pain syndromes accounted for 42.4% (n = 861) overall; chronic pain 29.4% (n = 598;), arthritis 9.3% (n = 188), and headache 3.7% (n = 75;). Across all 21 illnesses, headache was a symptom treated with cannabis in 24.9% (n = 505). These patients were given the ID Migraine™ questionnaire, with 68% (n = 343) giving 3 "Yes" responses, 20% (n = 102) giving 2 "Yes" responses (97% and 93% probability of migraine, respectively). Therefore, 88% (n = 445) of headache patients were treating probable migraine with cannabis. Hybrid strains were most preferred across all pain subtypes, with "OG Shark" the most preferred strain in the ID Migraine™ and headache groups. Many pain patients substituted prescription medications with cannabis (41.2-59.5%), most commonly opiates/opioids (40.5-72.8%). Prescription substitution in headache patients included opiates/opioids (43.4%), anti-depressant/anti-anxiety (39%), NSAIDs (21%), triptans (8.1%), anti-convulsants (7.7%), muscle relaxers (7%), ergots (0.4%). CONCLUSIONS: Chronic pain was the most common reason for cannabis use, consistent with most registries. The majority of headache patients treating with cannabis were positive for migraine. Hybrid strains were preferred in ID Migraine™, headache, and most pain groups, with "OG Shark", a high THC (Δ9-tetrahydrocannabinol)/THCA (tetrahydrocannabinolic acid), low CBD (cannabidiol)/CBDA (cannabidiolic acid), strain with predominant terpenes β-caryophyllene and β-myrcene, most preferred in the headache and ID Migraine™ groups. This could reflect the potent analgesic, anti-inflammatory, and anti-emetic properties of THC, with anti-inflammatory and analgesic properties of β-caryophyllene and β-myrcene. Opiates/opioids were most commonly substituted with cannabis. Prospective studies are needed, but results may provide early insight into optimizing crossbred cannabis strains, synergistic biochemical profiles, dosing, and patterns of use in the treatment of headache, migraine, and chronic pain syndromes.

11 Article Low-Dose Propofol for Pediatric Migraine: A Prospective, Randomized Controlled Trial. 2018

Sheridan, David C / Hansen, Matthew L / Lin, Amber L / Fu, Rongwei / Meckler, Garth D. ·Department of Emergency Medicine, Oregon Health & Science University, Portland, Oregon. · Department of Pediatrics, Pediatric Emergency Medicine, University of British Columbia, Vancouver, British Columbia, Canada; British Columbia Children's Hospital, Vancouver, British Columbia, Canada. ·J Emerg Med · Pubmed #29456086.

ABSTRACT: BACKGROUND: Migraine headaches are a common reason for pediatric emergency department (ED) visits. Small studies suggest the potential efficacy of sub-anesthetic doses of propofol for migraine with a favorable side effect profile and potentially decreased length of stay (LOS). OBJECTIVE: The objective of this study was to compare the efficacy of low-dose propofol (LDP) to standard therapy (ST) in pediatric migraine treatment. METHODS: We conducted a prospective, pragmatic randomized controlled trial from April 2014 through June 2016 in the ED at two pediatric hospitals. Patients aged 7-19 years were eligible if they were diagnosed with migraine by the emergency physician and had a presenting visual analog pain score (VAS) of 6-10. Primary outcome was the percent of pain reduction. Secondary outcomes were ED LOS, 24-h rebound headache, return visits to the ED, and adverse reactions. RESULTS: Seventy-four patients were enrolled, but 8 were excluded, leaving 66 patients in the final analysis (36 ST, 30 LDP). Pain reduction was 59% for ST and 51% for LDP (p = 0.34) with 72.2% vs. 73.3% achieving a VAS ≤ 4 with initial therapy (p = 0.92). There was a nonsignificant trend toward shorter median LOS from drug administration to final disposition favoring propofol (79 min vs. 111 min; p = 0.09). Rebound headache was significantly more common in the ST vs. LDP group (66.7% vs. 25.0%; p = 0.01). CONCLUSIONS: LDP did not achieve better pain reduction than ST, however, LDP was associated with significantly fewer rebound headaches and a nonsignificant trend toward shorter median LOS from drug administration to disposition.

12 Article Investigating Effects of Sex Differences and Prior Concussions on Symptom Reporting and Cognition Among Adolescent Soccer Players. 2018

Brooks, Brian L / Silverberg, Noah / Maxwell, Bruce / Mannix, Rebekah / Zafonte, Ross / Berkner, Paul D / Iverson, Grant L. ·Neurosciences Program, Alberta Children's Hospital, Calgary, Alberta, Canada. · Departments of Pediatrics, Clinical Neurosciences, and Psychology, University of Calgary, Calgary, Alberta, Canada. · Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada. · Division of Physical Medicine and Rehabilitation, University of British Columbia; Vancouver Coastal Health Research Institute Rehabilitation Research Program, Vancouver, British Columbia, Canada. · Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, Massachusetts, USA. · Department of Computer Science, Colby College, Waterville, Maine, USA. · Division of Emergency Medicine, Brain Injury Center, Boston Children's Hospital, Boston, Massachusetts, USA. · Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital, Massachusetts General Hospital, Brigham and Women's Hospital, Harvard Medical School, and Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Boston, Massachusetts, USA. · Health Services and the Department of Biology, Colby College, Waterville, Maine, USA. · Department of Physical Medicine and Rehabilitation, Harvard Medical School, Spaulding Rehabilitation Hospital, Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, MassGeneral Hospital for Children Sport Concussion Program, Boston, Massachusetts, USA. ·Am J Sports Med · Pubmed #29323926.

ABSTRACT: BACKGROUND: There has been increasing concern regarding the possible effect of multiple concussions on the developing brain, especially for adolescent females. Hypothesis/Purpose: The objectives were to determine if there are differences in cognitive functioning, symptom reporting, and/or sex effects from prior concussions. In a very large sample of youth soccer players, it was hypothesized that (1) there would be no differences in cognitive test performance between those with and without prior concussions, (2) baseline preseason symptoms would be better predicted by noninjury factors than concussion history, and (3) males and females with prior concussions would not have differences in cognition or symptoms. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Participants included 9314 youth soccer players (mean = 14.8 years, SD = 1.2) who completed preseason baseline cognitive testing, symptom reporting, and a health/injury history questionnaire from the ImPACT battery (Immediate Post-concussion Assessment and Cognitive Testing). On the basis of injury history, athletes were grouped by number of prior concussions: 0 (boys, n = 4012; girls, n = 3963), 1 (boys, n = 527; girls, n = 457), 2 (boys, n = 130; girls, n = 97), or ≥3 (boys, n = 73; girls, n = 55). The primary measures were the 4 primary cognitive scores and the total symptom ratings from ImPACT. Primary outcomes were assessed across injury groups, controlling for age, sex, learning disability, attention-deficit/hyperactivity disorder (ADHD), treatment for headaches/migraines, substance abuse, and mental health problems. RESULTS: Cognitive test performance was not associated with concussion history but was associated with sex, age, learning disability, ADHD, and prior mental health problems. Greater symptom reporting was more strongly associated with psychiatric problems, older age, learning disability, substance abuse, headaches, being female, and ADHD than with a history of multiple concussions. Boys and girls did not differ on cognitive scores or symptom reporting based on a history of concussion. CONCLUSION: In this very large sample of youth soccer players with prior concussion, there was no evidence of negative effects on cognition, very weak evidence of negative effects on symptom reporting, and no evidence of sex × concussion differences in cognition or symptom reporting.

13 Article Comorbidity increases the risk of relapse in multiple sclerosis: A prospective study. 2017

Kowalec, Kaarina / McKay, Kyla A / Patten, Scott B / Fisk, John D / Evans, Charity / Tremlett, Helen / Marrie, Ruth Ann / Anonymous1481021. ·From the Faculty of Medicine (K.K., K.A.M., H.T.), Division of Neurology and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver · Cumming School of Medicine (S.B.P.), Departments of Community Health Sciences and Psychiatry, University of Calgary · Department of Psychiatry, Psychology & Neuroscience and Medicine (J.D.F.), Dalhousie University, Nova Scotia Health Authority · College of Pharmacy and Nutrition (C.E.), University of Saskatchewan, Saskatoon · and Departments of Internal Medicine and Community Health Sciences (R.A.M.), Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada. ·Neurology · Pubmed #29117961.

ABSTRACT: OBJECTIVE: To evaluate the association between comorbidity and relapse rate in individuals with multiple sclerosis (MS). METHODS: We recruited individuals with prevalent relapsing-onset MS from 4 Canadian MS Clinics to participate in a 2-year prospective multicenter cohort study involving cross-sectional assessment of comorbidities and relapses. Comorbidities were recorded using questionnaires, and relapses were captured from medical records at each visit. The association between comorbidities at baseline and relapse rate over the subsequent 2-year follow-up period was examined using Poisson regression, adjusting for age, sex, disability, disease duration, and treatment status. RESULTS: Of 885 participants, 678 (76.6%) were women, averaging age 48.2 years at baseline. Anxiety (40.2%), depression (21.1%), hypertension (17.7%), migraine (18.1%), and hyperlipidemia (11.9%) were the most prevalent comorbidities. The frequency of participants experiencing relapses remained constant at 14.9% and 13.2% in years 1 and 2 post-baseline. After adjustment, participants reporting ≥3 baseline comorbidities (relative to none) had a higher relapse rate over the subsequent 2 years (adjusted rate ratio 1.45, 95% confidence interval [CI] 1.00-2.08). Migraine and hyperlipidemia were associated with increased relapse rate (adjusted rate ratio 1.38; 95% CI 1.01-1.89 and 1.67; 95% CI 1.07-2.61, respectively). CONCLUSIONS: Individuals with migraine, hyperlipidemia, or a high comorbidity burden (3 or more conditions) had an increased relapse rate over 2 years. These findings have potential implications for understanding the pathophysiology of MS relapses, and suggest that closer monitoring of individuals with specific or multiple comorbidities may be needed. Future research is needed to understand if the presence of comorbidity warrants a tailored approach to MS management.

14 Article Evaluating the safety of β-interferons in MS: A series of nested case-control studies. 2017

de Jong, Hilda J I / Kingwell, Elaine / Shirani, Afsaneh / Cohen Tervaert, Jan Willem / Hupperts, Raymond / Zhao, Yinshan / Zhu, Feng / Evans, Charity / van der Kop, Mia L / Traboulsee, Anthony / Gustafson, Paul / Petkau, John / Marrie, Ruth Ann / Tremlett, Helen / Anonymous1091269. ·From the Division of Neurology and Centre for Brain Health (H.J.I.d.J., E.K., A.S., Y.Z., F.Z., M.L.v.d.K., A.T., H.T.), Department of Medicine, and Vancouver Coastal Health Research Institute, University of British Columbia, Canada · School for Mental Health and Neuroscience (H.J.I.d.J., J.W.C.T., R.H.), Maastricht University Medical Center, the Netherlands · College of Pharmacy and Nutrition (C.E.), University of Saskatchewan, Saskatoon, Canada · Department Public Health Sciences (M.L.v.d.K.), Karolinska Institutet, Stockholm, Sweden · Department of Statistics (P.G., J.P.), University of British Columbia, Vancouver, Canada · and Departments of Internal Medicine and Community Health Sciences (R.A.M.), Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada. ·Neurology · Pubmed #28500224.

ABSTRACT: OBJECTIVE: To examine the association between interferon-β (IFN-β) and potential adverse events using population-based health administrative data in British Columbia, Canada. METHODS: Patients with relapsing-remitting multiple sclerosis (RRMS) who were registered at a British Columbia Multiple Sclerosis Clinic (1995-2004) were eligible for inclusion and were followed up until death, absence from British Columbia, exposure to a non-IFN-β disease-modifying drug, or December 31, 2008. Incidence rates were estimated for each potential adverse event (selected a priori and defined with ICD-9/10 diagnosis codes from physician and hospital claims). A nested case-control study was conducted to assess the odds of previous IFN-β exposure for each potential adverse event with at least 30 cases. Cases were matched by age (±5 years), sex, and year of cohort entry, with up to 20 randomly selected (by incidence density sampling) controls. Odds ratios (ORs) with 95% confidence intervals (95% CIs) were estimated with conditional logistic regression adjusted for age at cohort entry. RESULTS: Of the 2,485 eligible patients, 77.9% were women, and 1,031 were treated with IFN-β during follow-up. From the incidence analyses, 27 of the 47 potential adverse events had at least 30 cases. Patients with incident stroke (OR CONCLUSIONS: Among patients with RRMS, IFN-β was associated with a 1.8- and 1.6-fold increase in the risk of stroke and migraine and 1.3-fold increases in depression and hematologic abnormalities.

15 Article In vivo imaging reveals that pregabalin inhibits cortical spreading depression and propagation to subcortical brain structures. 2017

Cain, Stuart M / Bohnet, Barry / LeDue, Jeffrey / Yung, Andrew C / Garcia, Esperanza / Tyson, John R / Alles, Sascha R A / Han, Huili / van den Maagdenberg, Arn M J M / Kozlowski, Piotr / MacVicar, Brian A / Snutch, Terrance P. ·Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; scain@msl.ubc.ca snutch@msl.ubc.ca. · Djavad Mowafaghian Center for Brain Health, University of British Columbia, Vancouver, BC V6T 1Z4, Canada. · UBC MRI Research Centre, University of British Columbia, Vancouver, BC V6T 1Z4, Canada. · Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada. · Department of Human Genetics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands. · Department of Neurology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands. ·Proc Natl Acad Sci U S A · Pubmed #28223480.

ABSTRACT: Migraine is characterized by severe headaches that can be preceded by an aura likely caused by cortical spreading depression (SD). The antiepileptic pregabalin (Lyrica) shows clinical promise for migraine therapy, although its efficacy and mechanism of action are unclear. As detected by diffusion-weighted MRI (DW-MRI) in wild-type (WT) mice, the acute systemic administration of pregabalin increased the threshold for SD initiation in vivo. In familial hemiplegic migraine type 1 mutant mice expressing human mutations (R192Q and S218L) in the Ca

16 Article Inpatient Pediatric Migraine Treatment: Does Choice of Abortive Therapy Affect Length of Stay? 2016

Sheridan, David C / Meckler, Garth D. ·Department of Emergency Medicine, Oregon Health & Science University, Portland, OR. Electronic address: sheridda@ohsu.edu. · Department of Pediatrics, Pediatric Emergency Medicine, University of British Columbia BC Children's Hospital, Vancouver, British Columbia, Canada. ·J Pediatr · Pubmed #27634627.

ABSTRACT: OBJECTIVE: To describe the inpatient management of pediatric migraine and the association between specific medications and hospital length of stay (LOS). STUDY DESIGN: Historical cohort study review of patients age <19 years of age admitted to a single tertiary care children's hospital between 2010 and 2015 for treatment of migraine headache. RESULTS: The cohort consisted of 58 encounters with an average patient age of 14.3 years (SD 3.2 years) with a female predominance (62%). The mean number of inpatient medications received by patients was 3 (range 1-7), with dopamine antagonists and dihydroergotamine used most commonly (67% and 59% of encounters, respectively). The average LOS was 56 hours (95% CI 48.2-63.2) and did not vary by medication received, although patients who received an opioid had a significantly longer LOS (79.2 vs 47.9 hours respectively; P < .001). CONCLUSIONS: Children admitted to the hospital for treatment of migraine headache frequently require a large number of medications over an average hospital LOS of more than 2 days without apparent differences based on medication received other than prolonged stays for subjects who received opioids.

17 Article Spinal Cord Injury and Migraine Headache: A Population-Based Study. 2015

Warner, Freda M / Cragg, Jacquelyn J / Weisskopf, Marc G / Kramer, John K. ·School of Kinesiology, University of British Columbia, Vancouver, BC, Canada; International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, BC, Canada. · International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, BC, Canada; Harvard School of Public Health Neuroepidemiology Research Group, Boston, MA, United States of America. · Harvard School of Public Health Neuroepidemiology Research Group, Boston, MA, United States of America. ·PLoS One · Pubmed #26308549.

ABSTRACT: Migraine headaches are a common neurological condition, negatively impacting health and quality of life. The association between migraines and spinal cord injury (SCI) is intriguing to consider from the perspective that migraine headaches may be acquired in response to damage in the spinal cord [corrected].The primary objective of this study was to further examine the association between SCI and migraine headache, controlling for potential confounding variables. A secondary objective was to determine the impact of migraine headaches on self-perceived health. Data from a sample of 61,047 participants were obtained from the cross-sectional Canadian Community Health Survey. Multivariable logistic regression was used to explore the association between SCI and migraine headache using probability weights and adjusting for confounders. The multivariable age- and sex-adjusted model revealed a strong association between SCI and migraine headache, with an adjusted odds ratio for migraine of 4.82 (95% confidence interval [3.02, 7.67]) among those with SCI compared to those without SCI. Further, individuals who experienced both SCI and migraine tended to report poorer perceived general health compared with the other groups (i.e., SCI and no migraine). In conclusion, this study established a strong association between SCI and migraine headache. Further research is needed to explore the possible mechanisms underlying this relationship. Improvements in clinical practice to minimize this issue could result in significant improvements in quality of life.

18 Article Public Drug Coverage and Its Impact on Triptan Use Across Canada: A Population-Based Study. 2015

Amadio, Anthony / Lee, Kathy / Yao, Zhan / Camacho, Ximena / Knowles, Sandra / Lay, Christine / Paterson, J Michael / Hunt, Jordan / Gomes, Tara / Anonymous1230823. ·Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, Canada. · Canadian Institute for Health Information, Toronto, ON, Canada. · Institute for Clinical Evaluative Sciences, Toronto, ON, Canada. · The Leslie Dan Faculty of Pharmacy, Toronto, ON, Canada. · Keenan Research Centre of The Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada. · Department of Medicine (Neurology), Women's College Hospital, University of Toronto, Toronto, ON, Canada. · Institute of Health Policy, Management, and Evaluation, Toronto, ON, Canada. · Department of Family Medicine, McMaster University, Hamilton, ON, Canada. ·Headache · Pubmed #25754431.

ABSTRACT: BACKGROUND: Public drug coverage for triptan medications varies across jurisdictions in Canada, which may lead to differences in usage patterns and patient risk for medication overuse headache. METHODS: We conducted a population-based, cross-sectional analysis of publicly funded triptan use in seven provinces across Canada from January 1, 2012 to December 31, 2012. All patients who had filled at least one prescription for a triptan during the study period were included. We defined quantity limits of 6, 12, and 18 triptan units per month to assess the prevalence of high volumes of triptan use, which may place patients at risk for medication overuse headaches, and compared this prevalence between provinces with different funding restrictions. RESULTS: We identified 14,085 publicly funded users of triptans in 2012 in the seven provinces studied, 82.5% of whom were aged less than 65 years (N = 11,631). The prevalence of triptan use ranged substantially by province, from 0.04% in Ontario to a maximum of 1.0% in Manitoba (P < .001). Furthermore, the percentage of patients in each province using more than 6, 12, or 18 units per month differed significantly between provinces (P < .001). In particular, the percentage of patients treated with more than 6 units per month ranged from as low as 2.1% in Saskatchewan to 43.8% in Ontario. CONCLUSIONS: Differing public drug reimbursement criteria for triptans may be one contributing factor that has led to our observation of considerable variation in both prevalence of triptan prescribing and potential overuse of these medications. We offer that monthly quantity limits may be considered as a tool to decrease risks for medication overuse headache.

19 Article Migraine and attention to visual events during mind wandering. 2015

Kam, Julia W Y / Mickleborough, Marla J S / Eades, Chelsea / Handy, Todd C. ·Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver, BC, Canada, kamjulia@gmail.com. ·Exp Brain Res · Pubmed #25700669.

ABSTRACT: Although migraine is traditionally categorized as a primary headache disorder, the condition is also associated with abnormalities in visual attentional function in between headache events. Namely, relative to controls, migraineurs show both a heightened sensitivity to nominally unattended visual events, as well as decreased habituation responses at sensory and post-sensory (cognitive) levels. Here we used event-related potentials (ERPs) to examine whether cortical hypersensitivities in migraineurs extend to mind wandering, or periods of time wherein we transiently attenuate the processing of external stimulus inputs as our thoughts drift away from the on-going task at hand. Participants performed a sustained attention to response task while they were occasionally queried as to their attentional state-either "on-task" or "mind wandering." We then analyzed the ERP responses to task-relevant stimuli as a function of whether they immediately preceded an on-task versus mind wandering report. We found that despite the commonly reported heightened visual sensitivities in our migraine group, they nevertheless manifest a reduced cognitive response during periods of mind wandering relative to on-task attentional states, as measured via amplitude changes in the P3 ERP component. This suggests that our capacity to attenuate the processing of external stimulus inputs during mind wandering is not necessarily impaired by the class of cortical hypersensitivities characteristic of the interictal migraine brain.

20 Article New frontiers and clinical applications for botulinum neuromodulators. 2015

Jagdeo, Jared / Carruthers, Alastair / Smith, Kevin C. ·Department of Dermatology, UC Davis Medical Center, Sacramento, California, Dermatology Service, Sacramento VA Medical Center, Mather, California, Department of Dermatology, SUNY Downstate Medical Center, Brooklyn, New York Department of Dermatology and Skin Science, University of British Columbia, Vancouver, BC, Canada Private Practice, Niagara Falls, Ontario, Canada. ·Dermatol Surg · Pubmed #25548840.

ABSTRACT: -- No abstract --

21 Article Occipital nerve block for the short-term preventive treatment of migraine: A randomized, double-blinded, placebo-controlled study. 2015

Dilli, Esma / Halker, Rashmi / Vargas, Bert / Hentz, Joseph / Radam, Teresa / Rogers, Robert / Dodick, David. ·University of British Columbia, Department of Medicine, Canada esma.dilli@vch.ca. · Mayo Clinic, Department of Neurology, USA. ·Cephalalgia · Pubmed #25505035.

ABSTRACT: BACKGROUND: Occipital nerve (ON) injections with corticosteroids and/or local anesthetics have been employed for the acute and preventive treatment of migraine for decades. However, to date there is no randomized, placebo-controlled evidence to support the use of occipital nerve block (ONB) for the prevention of migraine. OBJECTIVE: The objective of this article is to determine the efficacy of ONB with local anesthetic and corticosteroid for the preventive treatment of migraine. PARTICIPANTS AND METHODS: Patients between 18 and 75 years old with ICHD-II-defined episodic (> 1 attack per week) or chronic migraine (modified ICHD-II as patients with > 10 days with consumption of acute medications were permitted into the study) were randomized to receive either 2.5 ml 0.5% bupivacaine plus 0.5 ml (20 mg) methylprednisolone over the ipsilateral (unilateral headache) or bilateral (bilateral headache) ON or 2.75 ml normal saline plus 0.25 ml 1% lidocaine without epinephrine (placebo). Patients completed a one-month headache diary prior to and after the double-blind injection. The primary outcome measure was defined as a 50% or greater reduction in the frequency of days with moderate or severe migraine headache in the four-week post-injection compared to the four-week pre-injection baseline period. RESULTS: Thirty-four patients received active and 35 patients received placebo treatment. Because of missing data, the full analysis of 33 patients in the active and 30 patients in the placebo group was analyzed for efficacy. In the active and placebo groups respectively, the mean frequency of at least moderate (mean 9.8 versus 9.5) and severe (3.6 versus 4.3) migraine days and acute medication days (7.9 versus 10.0) were not substantially different at baseline. The percentage of patients with at least a 50% reduction in the frequency of moderate or severe headache days was 30% for both groups (10/30 vs nine of 30, Δ 0.00, 95% CI -0.22 to 0.23). CONCLUSIONS: Greater ONB does not reduce the frequency of moderate to severe migraine days in patients with episodic or chronic migraine compared to placebo.The study was registered with ClinicalTrial.gov (NCT00915473).

22 Article Cognitive processing of visual images in migraine populations in between headache attacks. 2014

Mickleborough, Marla J S / Chapman, Christine M / Toma, Andreea S / Handy, Todd C. ·Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver BC, Canada. Electronic address: marla.mick@usask.ca. · Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver BC, Canada. ·Brain Res · Pubmed #25072184.

ABSTRACT: BACKGROUND AND OBJECTIVE: People with migraine headache have altered interictal visual sensory-level processing in between headache attacks. Here we examined the extent to which these migraine abnormalities may extend into higher visual processing such as implicit evaluative analysis of visual images in between migraine events. METHODS: Specifically, we asked two groups of participants--migraineurs (N=29) and non-migraine controls (N=29)--to view a set of unfamiliar commercial logos in the context of a target identification task as the brain electrical responses to these objects were recorded via event-related potentials (ERPs). Following this task, participants individually identified those logos that they most liked or disliked. We applied a between-groups comparison of how ERP responses to logos varied as a function of hedonic evaluation. RESULTS: Our results suggest migraineurs have abnormal implicit evaluative processing of visual stimuli. Specifically, migraineurs lacked a bias for disliked logos found in control subjects, as measured via a late positive potential (LPP) ERP component. CONCLUSIONS: These results suggest post-sensory consequences of migraine in between headache events, specifically abnormal cognitive evaluative processing with a lack of normal categorical hedonic evaluation.

23 Article Effectiveness of riboflavin in pediatric migraine prevention. 2014

Sherwood, Michelle / Goldman, Ran D. ·BC Children's Hospital, Department of Pediatrics, Room K4-226, Ambulatory Care Bldg, 4480 Oak St, Vancouver, BC V6H 3V4. rgoldman@cw.bc.ca. ·Can Fam Physician · Pubmed #24627379.

ABSTRACT: QUESTION: The rate of migraine diagnosed among children is increasing. Is riboflavin, an alternative to traditional pharmacologic agents, effective and safe for prevention of migraine in children? ANSWER: Because migraine is a very common condition in childhood and adolescence, often contributing to substantial burden of illness, there is increased interest in alternatives to traditional pharmacologic prevention. The expectation is that over-the-counter alternative medication will be less toxic, better tolerated, and have fewer side effects. A few studies in adults show that riboflavin (vitamin B2) might decrease frequency of migraine headaches. It has become common practice to recommend that children try riboflavin to prevent migraine; however, research on riboflavin use in children is inconclusive.

24 Article Hemiplegic migraine, seizures, progressive spastic paraparesis, mood disorder, and coma in siblings with low systemic serotonin. 2011

Horvath, Gabriella A / Selby, Kathryn / Poskitt, Ken / Hyland, Keith / Waters, Paula J / Coulter-Mackie, Marion / Stockler-Ipsiroglu, Sylvia G. ·British Columbia Children's Hospital, Canada. ·Cephalalgia · Pubmed #22013141.

ABSTRACT: BACKGROUND: Serotonin has an important role in vascular resistance and blood pressure control, and a functional serotonin transporter polymorphism has been associated with migraine. Disturbances in serotonin metabolism have been associated with autism, depression, and myoclonus related conditions, but serotonin has far more functions in the body. Familial hemiplegic migraine is a rare autosomal dominant subtype of migraine with aura in which attacks are associated with hemiparesis. CASES: We present two siblings with hemiplegic migraine, depression, progressive spastic paraparesis, myelopathy, and spinal cord atrophy. One of the sisters presented with prolonged coma after a migraine episode. Both sisters were found to have low cerebrospinal fluid serotonin metabolite (5-hydroxyindoleacetic acid), low platelet serotonin levels, and diminished serotonin transport capacity. Their clinical symptoms improved on 5-hydroxytryptophan replacement therapy. Mutational analysis of the CACNA1A and ATP1A2 genes was negative. CONCLUSION: This is the first time that systemic serotonin deficiency has been described in familial hemiplegic migraine. We hypothesize that the deficiency of serotonin transport may be part of a complex cellular membrane trafficking dysfunction involving not only the serotonin transporter but also other transporters and ion channels.

25 Article Reflexive attentional orienting in migraineurs: The behavioral implications of hyperexcitable visual cortex. 2011

Mickleborough, Marla J S / Hayward, Jake / Chapman, Christine / Chung, Janelle / Handy, Todd C. ·University of British Columbia, Canada. marla@psych.ubc.ca ·Cephalalgia · Pubmed #22009991.

ABSTRACT: INTRODUCTION: Although migraine is classified as a headache disorder, a key part of migraine pathophysiology is a heightened excitability of visual cortices in between headache events. The goal of our study was to examine the behavioral impact of this visuocortical hyperexcitability, in terms of its effect on reflexive visual attentional orienting. METHODS AND RESULTS: In Experiment 1, using a non-predictive spatial cuing task that relied on sensory-evoked responses in the visual cortex for triggering attentional orienting, we found that migraineurs had greater attentional enhancement of manual target responses, relative to non-migraine controls. In two control experiments we confirmed that this heightened attention effect in migraineurs is not due to exaggerated reflexive orienting responses in general, but rather, it appears to be specifically associated with sensory-evoked attentional triggers. DISCUSSION: Taken together, this confirms that the functional consequences of hyperexcitable visual cortex in migraineurs are not just purely sensory in nature, but directly impact at least some forms of reflexive attention. This provides evidence of at least one cognitive implication of hyperexcitable visual cortical responses in migraineurs, namely heightened reflexive visual-spatial orienting specific to sudden-onset peripheral events.