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EEG alpha power varies under many circumstances requiring visual attention. However, mounting evidence indicates that alpha may not only serve visual processing, but also the processing of stimuli presented in other sensory modalities, including hearing. We previously showed that alpha dynamics during an auditory task vary as a function of competition from the visual modality (Clements et al., 2022) suggesting that alpha may be engaged in multimodal processing. Here we assessed the impact of allocating attention to the visual or auditory modality on alpha dynamics, during the preparatory period of a bimodal-cued conflict task. In this task, precues indicated the modality (vision, hearing) relevant to a subsequent reaction stimulus. This task afforded us the opportunity to assess alpha during modality-specific preparation and while switching between modalities. Alpha suppression following the precue occurred in all conditions indicating that it may reflect general preparatory mechanisms. However, we observed a switch effect when preparing to attend to the auditory modality, in which greater alpha suppression was elicited when switching to the auditory modality compared to repeating. No switch effect was evident when preparing to attend to visual information (although robust suppression did occur in both conditions). In addition, waning alpha suppression preceded error trials, irrespective of sensory modality. These findings indicate that alpha can be used to monitor the level of preparatory attention to process both visual and auditory information. These results support the emerging view that alpha band activity may index a general attention control mechanism used across modalities, at least vision and hearing.

Research into the nature of 1/f-like, non-oscillatory electrophysiological activity has grown exponentially in recent years in cognitive neuroscience. The shape of this activity has been linked to the balance between excitatory and inhibitory neural circuits, which is thought to be important for information processing. However, to date, it is not known whether the presentation of a stimulus induces changes in the parameters of 1/f activity, which are separable from the emergence of event-related potentials (ERPs). Here, we analyze event-related broadband changes in scalp-recorded EEG both before and after removing ERPs to demonstrate their confounding effect, and to establish whether there are genuine stimulus-induced changes in 1/f. Using data from a passive and an active auditory task (n=23), we found that the shape of the post-event spectra differed significantly from the pre-event spectra even after removing the frequency-content of ERPs. Further, a significant portion of this difference could be accounted for by a rotational shift in 1/f activity, manifesting as an increase in low and a decrease in high frequencies. Importantly, the magnitude of this rotational shift was related to the attentional demands of the task. This change in 1/f is consistent with increased inhibition following the onset of a stimulus, and likely reflects a disruption of ongoing excitatory activity proportional to processing demands. Finally, these findings contradict the central assumption of baseline normalization strategies in time-frequency analyses, namely that background EEG activity is stationary across time. As such, they have far-reaching consequences that cut across several subfields of neuroscience.Significance statementInterest in the functional role of the 1/f-like background brain activity has been growing exponentially in neuroscience. Yet, no study to date has demonstrated a clear relationship between information processing and 1/f activity by investigating event-related effects on its parameters. Here, we demonstrate for the first time that stimuli induce rotational changes in 1/f activity, independent from the occurrence of event-related potentials. Not only do these findings suggest that the assumption of stationary background activity in the analysis of neural oscillations is untenable, but they also suggest the presence of large-scale inhibition following stimulus onset, the magnitude of which is dependent on the demands of the task. These findings have far-reaching consequences that cut across several subfields of neuroscience.

Involuntary adaptations of breathing patterns to counter breathlessness may lead to dysfunctional breathing in obstructive lung diseases. However, no studies examining dysfunctional breathing in Chronic Obstructive Pulmonary Disease (COPD) have been reported. Patients with verified COPD (n=34), asthma (n=37) and a healthy control group (n=41) were recruited. All participants completed the Nijmegen questionnaire for dysfunctional breathing as well as measures of disease activity. Comparisons between groups employed analysis of variance with post-hoc Bonferroni analyses and Pearson correlation for associations. Patients with COPD had significantly higher Nijmegen questionnaire scores than asthmatics (COPD: 23.4±10.6 versus 17.3±10.6, p=0.016) and healthy individuals (14.3±9.6, p=0.002). Significantly more patients with COPD had severe dysfunctional breathing with Nijmegen scores >23 (47%; 16/34) compared to asthma (27%; 10/37) and healthy controls (17%; 7/41) respectively (p=0.019). Dysfunctional breathing was detected in ∼50% of patients with COPD, more so than in asthma or health. Strategies to reduce abnormal breathing behaviours may have important benefits for treatment of breathlessness in COPD.

Introduction: Vocal cord dysfunction (VCD) causes vocal cord narrowing during inspiration resulting in airflow obstruction and breathlessness. In asthma VCD can be found in up to 20% of stable asthmatics but few studies have examined coexisting VCD in exacerbated asthma and none in COPD. We hypothesised that VCD may occur frequently during acute asthma and COPD exacerbations. Method: Overall 34 patients with asthma exacerbations and 37 patients with exacerbations of COPD were studied in the emergency department (ED). All patients had a previous diagnosis of asthma or COPD confirmed by lung function. Asthma chronic disease severity was based on GINA and exacerbation severity based on a validated score. COPD chronic disease severity was based on GOLD criteria and exacerbation severity was based on BAP-65. Dynamic computerised tomography (CT) imaging was done as soon as possible after ED admission and VCD was diagnosed using 320-slice CT of the larynx. Results: In the overall group (n=71) VCD was detected in 20 cases (28%). Patients with COPD had VCD more often (14/37, 37.8%) than asthmatics (6/34, 17.6%, p=0.03). There were no associations between asthma or COPD, acute disease severity and presence of VCD. Patients with COPD had more VCD if they had severe/very severe chronic COPD (10/14, 71%) as opposed to mild/moderate (4/14, 31%). Conclusion: Surprisingly VCD was more frequently detected in COPD than in asthma. VCD should be considered a contributing factor during exacerbations of both diseases. Further studies are needed to determine how much VCD contributes to acute symptoms and to examine effective treatments for VCD in these clinical contexts.

SummaryBackground Abnormal vocal cord movements can cause laryngeal extrathoracic airway obstruction (often called vocal cord dysfunction – VCD) leading to asthma-like symptoms. These aberrant movements are characteristically present during inspiration and termed paradoxical vocal cord movement (PVCM). We have reported PVCM in up to 40% of severe asthmatics, but it is not known if PVCM is detectable in all patients with asthma-like symptoms and if the condition is more often associated with abnormal lung function. Objective We hypothesized that PVCM is frequently associated with asthma symptoms accompanied by airflow limitation. Studies examined whether PVCM is solely linked to experiencing asthma symptoms, or if PVCM is related to airflow limitation and/or other disease characteristics. Methods Patients with asthma symptoms were recruited from general practice and severe asthma clinics (n = 155). Pulmonary function measurements were conducted, asthma control and Nijmegen (dysfunctional breathing) questionnaires were administered and skin prick testing was carried out. PVCM was quantified using dynamic 320-slice computerized tomography of the larynx. Groups were divided into patients with FEV1 ≥ 80% predicted or FEV1 < 80% predicted and FEV1/FVC < 0.7. ATS/ERS definitions of severity were also applied and evaluated. Detection of PVCM in the groups was compared and analyses performed to identify features associated with PVCM. Results Overall (n = 155), PVCM was detected in 42 cases (27.1%). Patients with FEV1 20 (P = 0.04). Patients with FEV1 20 were more likely to have PVCM (OR = 9.3, P = 0.02). Conclusions and Clinical Relevance Paradoxical vocal cord movement is more often associated with asthma symptoms accompanied by airflow limitation and dysfunctional breathing. Further studies are needed to determine whether PVCM is induced by dysfunctional breathing practices and/or airway obstruction. How PVCM links with symptomatic asthma and VCD also requires evaluation.

BACKGROUND AND OBJECTIVE Multidisciplinary team (MDT) clinics use an integrated approach to individualize care of complex medical conditions. Vocal cord dysfunction (VCD) is a challenging condition that is likely to benefit from MDT clinics but this has not been researched. METHODS A prospective observational cohort study of a novel VCD MDT clinic was conducted in patients with suspected VCD. Relevant questionnaires, medical history, physical examination, spirometry, dynamic computerized tomography (CT) larynx and laryngoscopy were utilized and patients were allocated to treatment pathways depending on putative diagnosis. Speech pathology intervention with laryngeal retraining (LR) was offered and if LR therapy failed botulinum toxin injection was offered. Primary outcome was reductions in healthcare utilization. RESULTS Overall, 80 consecutive patients were included in analyses. A definitive diagnosis of VCD was made in 56 of 80 (70%) patients. After LR (n = 35), emergency department (ED)/hospital admissions declined significantly in the subsequent 12 months (P = 0.001). General practice visits also reduced (P

BACKGROUND MRI guidelines have been created to help clinicians order scans appropriately. Some scans in children are carried out under general anesthesia (GA) / sedation. PURPOSE To evaluate if the requirement for GA/sedation influences the way MRI brain scans are ordered. STUDY TYPE Retrospective. POPULATION Children with MRI brain scans in 2015 to 2017. FIELD STRENGTH 3T, 1.5T. ASSESSMENT Institutional Review Board approval for waiver of consent was obtained. Clinical MRI brain reports for children were classified into whether they conformed to the American College of Radiology (ACR) 2013 guidelines by research assistants under supervision of a pediatric radiologist. Scans were sorted into those with normal brains or abnormality. STATISTICAL TEST The statistical difference between groups was assessed using t-test for continuous variables and chi-square test for categorical variables with IBM SPSS 19. RESULTS Of the total 1893 MRI scans, 431 were performed under GA and six under sedation. Of the 431 cases performed under GA/sedation, 383 (87.6%) were ordered according to guidelines. Of the 1456 cases that did not require GA/sedation, 710 (48.8%) conformed to guidelines. The percentage of scans ordered according to guidelines was 38.8% higher in those who had scans performed under GA/sedation (P

Asthma affects over 300 million people worldwide. Most asthmatics are well controlled with inhaled corticosteroids and long-acting beta-agonists; however, a proportion of patients are unresponsive and attain limited disease control. This group represents a considerable healthcare and financial burden, particularly patients who experience frequent exacerbations and require hospital admission. Development of new biological agents and disease biomarkers has provided novel avenues for treatment. These treatments have been highly successful, reducing exacerbations and yielding modest improvements in quality of life and lung function. However, only a proportion of severe asthmatics respond to this targeted treatment, highlighting the heterogeneity of severe asthma. One of the first biological therapies targeted immunoglobulin E (IgE) and demonstrated modest benefit but could only be used in a subgroup of patients. Recent research has shown that treatment aimed at the T helper-2-(Th2)-high pathways and cytokines such as interleukin (IL)-5, IL-4, and IL-13 may also be effective in another partially overlapping subgroup. A blood eosinophil count over a defined threshold (generally ≥300 cells/μl) was a reliable biomarker and identified the majority of responders in this group. Further discovery and validation of biological markers to define asthmatic phenotypes that may benefit from biological treatments remain an area of intense interest and research. We review the latest information pertaining to biological agents and demonstrate how patient responders may potentially be identified for treatment.

Background and Objective Abnormal vocal cord movement may coexist with asthma and cause additional upper/middle airway obstruction. The condition may be a form of muscular dystonia that could contribute to asthma resistant to optimised treatments. Botulinum toxin causes temporary paralysis of muscle and may be an effective local treatment that improves asthma control. Methods In an observational study, we evaluated the benefits of unilateral vocal cord injection with botulinum toxin in 11 patients (total 24 injections). Subjects had asthma resistant to optimised treatment and abnormal vocal cord movement. Responses after botulinum toxin treatment were assessed using asthma control test (ACT) scores, vocal cord narrowing quantified by computerised tomography (CT) of the larynx and spirometry. Side-effects were recorded. Results ACT scores improved overall (9.1 ± 2.4 before and 13.5 ± 4.5 after treatment; difference 4.4 ± 4.2; P

Vocal Cord Dysfunction in mild and severe asthma Introduction: Vocal cord dysfunction (VCD) causes vocal cord narrowing during inspiration resulting in airflow obstruction and may contribute to breathlessness in asthma. VCD is detected in more than 40% of severe disease but it is not known if the condition is limited to severe asthma and if dysfunctional breathing is associated. Method: Patients with mild to severe asthma (total n=155) were recruited from general practice and hospital asthma clinics and spirometry was conducted. VCD was diagnosed during inspiration using dynamic 320-slice computerised tomography (CT) of the larynx, a quantitative method capable of measuring real-time vocal cord dimensions during breathing. Excessive narrowing is recognised if a predetermined lower limit of normal is exceeded. Asthma control was evaluated using ACT and ACQ5 questionnaires and dysfunctional breathing was assessed via Nijmegen questionniare. VCD was compared in asthma severity. Results: In the overall group (n=155) VCD was detected during inspiration in 42 cases (27.1%). Patients with severe uncontrolled asthma (n=68) characterised by airflow limitation (FEV 1 Conclusion: VCD is frequently detected in asthma, more so in severe disease. Airflow limitation coupled with dysfunctional breathing has a strong association with VCD. Further studies are needed to determine if VCD worsens asthma symptoms and to ascertain which treatments can improve asthma severity.

Abnormal vocal cord movement may coexist with asthma and cause additional upper/middle airway obstruction. The condition may be a form of muscular dystonia that could contribute to asthma resistant to optimised treatments. Botulinum toxin causes temporary paralysis of muscle and may be an effective local treatment that improves asthma control.In an observational study, we evaluated the benefits of unilateral vocal cord injection with botulinum toxin in 11 patients (total 24 injections). Subjects had asthma resistant to optimised treatment and abnormal vocal cord movement. Responses after botulinum toxin treatment were assessed using asthma control test (ACT) scores, vocal cord narrowing quantified by computerised tomography (CT) of the larynx and spirometry. Side-effects were recorded.ACT scores improved overall (9.1 ± 2.4 before and 13.5 ± 4.5 after treatment; difference 4.4 ± 4.2; P0.001). There was also an improvement in airway size on CT larynx (time below lower limit of normal at baseline 39.4 ± 37.63% and improved to 17.6 ± 25.6% after injection; P = 0.032). Spirometry was not altered. One patient experienced an asthma exacerbation but overall side-effects were moderate, chiefly dysphonia and dysphagia.Although a placebo effect cannot be ruled out, local injection of botulinum toxin may be an effective treatment for intractable asthma associated with abnormal vocal cord movement. Further mechanistic studies and a double-blind randomised controlled trial of botulinum toxin treatment are merited.

Upper airway dysfunction may complicate asthma but has been largely ignored as an etiological factor. Diagnosis using endoscopic evaluation of vocal cord function is difficult to quantify, with limited clinical application.A novel imaging technique, dynamic 320-slice computerized tomography (CT), was used to examine laryngeal behavior in healthy individuals and individuals with asthma.Vocal cord movement was imaged using 320-slice CT larynx. Healthy volunteers were studied to develop and validate an analysis algorithm for quantification of normal vocal cord function. Further studies were then conducted in 46 patients with difficult-to-treat asthma.Vocal cord movement was quantified over the breathing cycle by CT using the ratio of vocal cord diameter to tracheal diameter. Normal limits were calculated, validated, and applied to evaluate difficult-to-treat asthma. Vocal cord movement was abnormal with excessive narrowing in 23 of 46 (50%) patients with asthma and severe in 9 (19%) patients (abnormal50% of inspiration or expiration time). Imaging also revealed that laryngeal dysfunction characterized the movement abnormality rather than isolated vocal cord dysfunction.Noninvasive quantification of laryngeal movement was achieved using CT larynx. Significant numbers of patients with difficult-to-treat asthma had excessive narrowing of the vocal cords. This new approach has identified frequent upper airway dysfunction in asthma with potential implications for disease control and treatment.

The FY06-07 goal was to advance the development of the Triosyn Super HEPA (TSH) media as an enhanced filtration material to be included in individual protection and collective protection end-use applications. Work was also done to pursue the development of the Triosyn T-series respirators. The objectives were achieved and resulted in a mature Triosyn Super HEPA filter material. A manufacturing process to incorporate Triosyn particles to glass fiber HEPA was developed to produce a material which maintains standard HEPA performance but also displays enhanced antimicrobial and chemical protection properties due to the presence of Triosyn. The antimicrobial performance of this media was demonstrated under a variety of testing conditions and following exposure to different microbial challenges. The Triosynated material's safety profile was also well-defined as measured by the iodine levels released in the effluent air under several exposure conditions. The chemical protection capability of the TSH was demonstrated following exposure of the media to surrogates of chemical warfare agents and potential incompatibilities originating from adverse interactions between iodine and the ASZM-TEDA carbon were investigated. This advanced TSH filter material is now ready for the next research steps which involve prototype designing for insertion into various individual and collective protection applications.

The intracarotid amobarbital test (IAT) is the most widely used procedure for pre-surgical evaluation of language lateralization in epileptic patients. However, apart from being invasive, this technique is not applicable in young children or patients who present mental retardation and/or language deficits. Functional magnetic resonance imaging (fMRI) is increasingly employed as a non-invasive alternative. Again, this method is more difficult to use with young children, especially hyperactive ones, since they have to remain motionless during data acquisition. The aim of this study was to determine whether near-infrared spectroscopy (NIRS) can be used as an alternative technique to investigate language lateralization in children and special populations. Unlike Wada test, NIRS is non-invasive, and it is more tolerant to movement artefacts than fMRI. In the present study, NIRS data were acquired in four epileptic children, a 12-year-old boy with pervasive developmental disorder and a 3-year-old, healthy child, as well as three healthy and two epileptic adults, while they performed a verbal fluency task and a control task. When applicable, the results were compared to the subjects' fMRI and/or IAT findings. Clear laterality of speech was obtained in all participants, including the two non-epileptic children, and NIRS results matched fMRI and IAT findings. These results, if replicable in larger samples, are encouraging and suggest that NIRS has the potential to become a viable, non-invasive alternative to IAT and fMRI in the determination of speech lateralization in children and clinical populations that cannot be submitted to more invasive techniques.