Effectiveness of non-pharmacological treatments for vestibular and oculomotor dysfunction in patients with persistent post-concussive symptoms : protocol for a systematic review and meta-analysis

Introduction: Concussion is a form of mild traumatic brain injury that disrupts brain function. Although symptoms are mostly transient, recovery can be delayed and result in persistent postconcussive symptoms (PPCS). Vestibular and oculomotor dysfunction are among the most debilitating impairments associated with PPCS. However, pharmacological interventions for these impairments are associated with deleterious side effects. Accordingly, increasing research has examined the utility of non-pharmacological interventions for PPCS. The aim of this review is to synthesise and evaluate the effectiveness of non-pharmacological interventions for the treatment of vestibular and oculomotor dysfunction for patients with PPCS. Methods and analysis: Systematic searches of MEDLINE, PubMed, Web of Science and Scopus will identify randomised controlled trials employing non-pharmacological treatments for vestibular and/or oculomotor dysfunction for PPCS. Such interventions may include, but are not limited to, vestibular rehabilitation, optokinetic stimulation and vestibulo-ocular reflex exercises. Assessments of oculomotor function will include versional eye movements, vergence eye movements, visual-fixation movements and accommodation response. Assessments of vestibular function will include the Fukuda Step test, functional balance tests, force displacement tests, and subjective reports of balance disruption or vertigo. Where appropriate, meta-analyses of standardised mean differences will be conducted using a random effects model for continuous outcomes. For dichotomous outcomes (improved vs not improved following treatment), effects will be expressed as relative risk. The impact of heterogeneity will be calculated using the I2 statistic. The Physiotherapy Evidence Database scale will be used to determine the methodological quality of individual studies and Grading of Recommendations, Assessment, Development and Evaluations used to assess the certainty and quality of evidence for each outcome. Ethics and dissemination: Ethical approval is not required for this review. Findings will be disseminated through peer-reviewed publications and conference presentations. PROSPERO registration number: CRD42021254720

Vestibular disability/handicap in Fibromyalgia : a questionnaire study

Fibromyalgia (FM) is a poorly understood, central pain processing disorder characterized by a broad range of symptoms, such as chronic pain, sleep disruption, chronic fatigue, and psychosomatic symptoms. In addition, recent studies have shown that FM patients also experience dizziness. We aimed to establish a prevalence rate of vestibular symptoms in a population of FM patients through a battery of questionnaires investigating socio-demographic, clinical and psychological characteristics, combined with the Dizziness Handicap Inventory (DHI) and the Situational Vertigo Questionnaire (SVQ). A total of 277 respondents, officially diagnosed with FM, completed the full study, while 80 controls were also included for DHI and SVQ questionnaires. We found that FM participants were significantly affected by vestibular symptoms, which correlated with FM-associated pain and non-pain symptoms. The dizziness reported by FM participants showed peculiar features suggesting an FM-intrinsic mechanism of vestibular dysfunction, possibly linked to migraine and dysautonomia conditions. Correlations between dizziness and depressive mood (or neuroticism), revealed an impact of dizziness on psychological status, leading to depressive reactions and interpersonal difficulties, and possibly involving a noxious, self-sustained stress condition. In conclusion, data showed a manifesting dizziness condition in FM patients that warrants careful clinical attention due to its possible inherent role in the syndrome

Visual disorders and mal de debarquement syndrome : a potential comorbidity questionnaire-based study

Aim: Mal de debarquement syndrome (MdDS) is a neurological condition characterized by a constant sensation of self-motion; onset may be motion-triggered (MT) or non-motion-triggered/spontaneous (NMT/SO). People with MdDS experience similar symptoms to those with vertical heterophoria, a subset of binocular visual dysfunction. Hence, we aimed to explore potential visual symptom overlaps. Methods: MdDS patients (n=196) and controls (n=197) completed a visual health questionnaire. Results: Compared with controls, the MdDS group demonstrated higher visual disorder scores and visual complaints. NMT/SO participants reported unique visual symptoms and a higher prevalence of mild traumatic brain injury. Conclusion: Our findings suggest visual disorders may coexist with MdDS, particularly the NMT/SO subtype. The difference in visual dysfunction frequency and medical histories between subtypes, warrants further investigation into differing pathophysiological mechanisms. Plain language summary: MdDS is a condition where patients feel like they are always on a boat. It is typically triggered by passive motion-events (cruises, flights, etc.), but can develop after non-motion events. People with MdDS can experience symptoms like those with certain visual disorders, therefore we wanted to see if there were overlaps between these conditions. This study surveyed people with MdDS and individuals from the general population about visual health and found that the MdDS group reported a higher frequency of visual dysfunction symptoms. Compared with motion-triggered patients, non-motion patients reported unique visual symptoms. This demonstrates that visual disorders may coexist in MdDS. Tweetable abstract: Mal de debarquement syndrome #MdDS is a rare condition where patients feel like they are always on a boat. Given the overlap of symptoms between MdDS and a common visual disorder– these researchers turned their focus toward visual comorbidities and found some eye-raising results

Assessing the engagement rates and satisfaction levels of various clinical health science student sub-groups using supplementary elearning resources in an introductory anatomy and physiology unit

Purpose: Introductory anatomy and physiology provide a core knowledge base to students within clinical health science courses. Increased student numbers, as well as reduced access to laboratory-based cadaveric resources, have created a need for enhanced learning approaches to support learning. The streamlining of courses has also resulted in the need to effectively engage course sub-groups within large units. The purpose of this paper is to utilize the eLearning activities to investigate engagement and satisfaction levels within students undertaking an anatomy and physiology unit. Design/methodology/approach: A total of 19 formative quizzes were made available to students. Online practical anatomy laboratories covered anatomical content, and physiology quizzes covered physiological content. Student engagement was compared using frequency analysis across students studying varying courses. Satisfaction was determined by analyzing student’s feedback using frequency analysis. Findings: Students accessed the learning activities 29,898 times over semester, with the peak access (37 percent) prior to the closed book exams. The resources were utilized primarily as an exam preparation tool rather than consistently throughout semester. Out of the various courses, the Paramedicine, Physiotherapy and Podiatry students were the most engaged, with the highest percent of “engaged/highly engaged” students. Students from various courses shared very similar views of the perceived benefit of the eLearning activities. Practical implications: These results indicated a difference in engagement levels between the students of various course sub-groups, and therefore suggests that the development of course-specific eLearning activities is necessary in large, streamlined units to achieve a more focused approach to support students’ learning, engagement and success, so that positive and beneficial learning experiences are ensured for all students. Originality/value: These results suggest that in the future, development of eLearning activities is necessary to achieve a more focused approach to support students’ learning, engagement and success, so that positive and beneficial learning experiences are ensured for all

Measuring the value of a digital supplemental resource

Supplemental resources in science education are made available to students based on the belief that they will improve coursebased student learning. This belief is ubiquitous, with supplemental resources being a traditional component of physiology education. In addition, the recent large-scale transition to remote learning caused by the Covid-19 pandemic suggests an increased relevance and necessity of digital versions of supplemental resources. However, the use of a supplemental resource is entirely dependent on whether students view it as beneficial. If students in a specific course do not perceive a supplemental resource as useful, there is little reason to believe the resources will be used and are worthy of investment. Consequently, measurement of student perception regarding the effectiveness of any digital learning tool is essential for educators and institutions in order to prioritize resources and make meaningful recommendations to students. In this study, a survey was used to determine student perceptions of a digital, supplemental resource. Quantitative methods, including exploratory factor analysis, were performed on data collected from the survey to examine the dimensionality and functionality of this survey. The findings from this study were used to devise an improved, standardized (i.e., reliable and valid) survey that can be used and adapted by physi3ology researchers and educators to determine student perception of a digital supplemental resource. The survey, with known construct validity and internal reliability, can provide useful information for administrators, instructors, and designers of digital supplemental resources

The effects of nicotine on the alpha-7 and beta-2 nicotinic acetycholine receptor subunits in the developing piglet brainstem

Exposure to cigarette smoke is a major risk factor for sudden infant death syndrome (SIDS). We tested the hypothesis that nicotine increases expression of the nicotinic acetylcholine receptor (nAChR) subunits a7 and b2 in a piglet model. Piglets exposed to 2 mg/kg/day nicotine for 14 days postnatally (n = 14) were compared to non-exposed controls (n = 14), (equal gender proportions). Immunohistochemistry was performed to identify and quantify changes in, a7 and b2 nAChR subunits in 8 nuclei of the medulla at both the rostral and caudal levels. Compared to controls, nicotine exposed piglets had decreased a7 in the rostral dorsal motor nucleus of the vagus (rDMNV) (p = 0.01), and increased b2 in the caudal DMNV (cDMNV) (p = 0.05), caudal nucleus of the spinal trigeminal tract (cNSTT) (p = 0.03) and caudal nucleus of the solitary tract (cNTS) (p = 0.04). Analysis by gender showed that in the control group, compared to males, females had higher b2 in the caudal hypoglossal (cXII) (p < 0.01) and caudal inferior olivary (p = 0.04) nuclei, while in the nicotine group females had higher b2 in the cDMNV (p = 0.02). Compared to control males, nicotine exposed males had lower b2 in the cXII (p < 0.01). Overall, changes in a7 were specific to nicotine exposure with no gender differentiation. Changes in b2 were more widespread but showed gender-specific effects. These findings provide evidence that early postnatal exposure to nicotine significantly affects nAChR subunit expressions in the developing brainstem

Influence of sex hormones on vestibular disorders

Purpose of review: Vestibular disorders are gender distributed with a higher prevalence in women. Although research has increased in this field, the mechanisms underlying this unbalance is unclear. This review summarises recent advances in this research sphere, and briefly discusses sex hormone effects on various vestibular conditions and highlights some recent theories. Recent findings Recent work has identified a direct link between aberrant gonadal hormone levels and vestibular dysfunction. Benign paroxysmal positional vertigo research suggests that the disorder may be linked to the rapid decrease in oestrogen, observed in menopausal women, which disrupts otoconial metabolism within the inner ear. A successful hormonal therapeutic intervention study has advanced our knowledge of hormonal influences in the inner ear in Meniere’s disease. Also, several studies have focused on potential mechanisms involved in the interaction between Vestibular Migraine, Mal de Debarquement Syndrome, and gonadal hormones. Summary: In females, gonadal hormones and sex-specific synaptic plasticity may play a significant role in the underlying pathophysiology of peripheral and central vestibular disorders. Overall, this review concludes that clinical assessment of female vestibular patients requires a multifaceted approach which includes auditory and vestibular medicine physicians, gynaecologists and/or endocrinologists, in conjunction with hormonal profile evaluations

Tracking the expression of GABAA receptor subunit α1 in rat auditory cortex, inferior colliculus and dorsal cochlear nucleus following noise-induced hearing loss

Damage to the cochlea, produced by exposure to a loud noise or a mechanical insult results in a range of changes in key auditory nuclei in the auditory pathway. Neuronal changes observed include plasticity of tonotopic representation, changes in the pattern of spontaneous activity and changes in the balance of excitatory and inhibitory transmitter systems. Moreover, damage to the cochlea frequently results in tinnitus. This suggests that one or more of these neuronal changes may be involved in tinnitus generation, although the mechanism remains to be elucidated. In an attempt to determine which area(s) may be involved in the generation of tinnitus, we are investigating neuronal changes at different levels of the auditory system (brainstem, midbrain and cortex). In this study we examine the timecourse of changes in the expression of the GABAA receptor in cochlear nucleus, inferior colliculus and auditory cortex up to 32 days following exposure to a 16 kHz bandpass (1/10th octave noise (115 dB SPL)). Male Long Evans rats (n = 10) were unilaterally exposed to the damaging noise for 1hour. At 0, 4, 8, 16 or 32 days rats were euthanased, their brains were removed and processed for immunohistochemistry to identify GABAARα1 subunit expression, which was subsequently quantified in the cochlear nucleus, inferior colliculus and auditory cortex. Over the course of the study period we saw significant changes in GABAARα1 expression. In auditory cortex these changes were evident from 4 days to 32 days where we saw a progressive increase in GABAARα1 up to twofold by 32 days. These increases may reflect an attempt to balance excitatory transmission, which is known to increase following noiseinduced hearing loss

Tracking the expression of GABAA receptor subunit a1, Glutamic-Acid Decarboxylase-67, N-Methyl-D-Aspartate receptor subunit 2A in rat auditory pathway following noise-induced hearing loss

Excessive exposure to loud noise or a mechanical insult results in damage to the cochlea, which can lead to a range of neuronal changes in key nuclei in the auditory pathway. Neuronal changes that have been observed include plasticity of tonotopic organisation, changes in the pattern of spontaneous activity and in the balance of excitatory and inhibitory transmitter systems. Moreover, a cochlear hearing loss is strongly associated with tinnitus in humans. This suggests that one or more of these neuronal changes may be involved in generating tinnitus, although the mechanisms and site remain unknown. In an attempt to determine which area(s) may be involved in the generation of tinnitus, we are investigating neuronal changes at a number of levels of the auditory pathway (auditory cortex (AC), inferior colliculus (IC) and dorsal cochlear nucleus (DCN)), primarily focusing on the balance of excitatory and inhibitory transmitter systems. In this study we examined the time-course of changes in the expression of the GABAA receptor subunit a1(GABAARa1), Glutamic-Acid Decarboxylase-67 (GAD-67), N-Methyl-D-Aspartate receptor subunit 2A (NMDAR2A) in AC, IC and DCN up to 32 days following exposure to a 16kHz band pass (1/10th octave noise (115 dB SPL))

Tracking tonotopic changes in the auditory system following noise-induced hearing loss

Unilateral noiseinduced hearing loss results in significant changes throughout the auditory system, but the manifestation of these changes depends on the nuclei under study. For instance, significant changes in the distribution of characteristic frequencies are observed in the inferior colliculus and primary auditory cortex following noiseinduced hearing loss, but only in the auditory cortex are these changes thought to be due to plastic reorganisation. Determining how these changes develop at different levels of the auditory pathway may shed light on the mechanisms responsible for the cortical plastic effects. Moreover, a growing body of evidence suggests that hearing loss and its accompanying neuronal changes are also involved in tinnitus. Thus, understanding the development of neuronal changes following noiseinduced hearing loss may aid us in our understanding of the neural basis of tinnitus. Accordingly, we examined neuronal changes at three different levels of the auditory pathway and at different time points up to 6 months following exposure to a damaging narrow band noise. Male Long Evans rats (n = 16) were unilaterally exposed to a 115 dB SPL 16 kHz 1/10th octave bandpass noise for 1hour. Principally, we were interested in the frequency representation and spontaneous activity of neurons in cochlear nucleus, inferior colliculus and auditory cortex. We recorded simultaneously from each of these structures using multichannel electrodes. Six unexposed rats served as controls. Hearing was assessed before and after the noise trauma procedure using auditory brainstem response (ABR) audiograms. Tone pips (144 kHz, 50 ms duration, 080 dB SPL, 1 Hz presentation rate) were used to obtain frequency tuning curves. At 30 days following the noise treatment the majority of multiunit clusters recorded in auditory cortex had two peaks in their frequency tuning curves (912 kHz and 3035 kHz), which bordered the spectral range of the noisetrauma stimulus. Similar changes were also evident when we recorded from animals 6 months after noise trauma. Less pronounced tonotopic changes were observed in the IC. The only reliable effect shown in the cochlear nucleus was an absence of neuronal activity in response to 16 kHz stimulation. In summary, the pattern of tonotopic changes is evident in the first month following noise exposure and remains unchanged for up to 6 months