Alpha oscillations related to self-other integration and distinction during live orchestral performance: A naturalistic case study.

Ensemble music performance requires musicians to achieve precise interpersonal coordination while maintaining autonomous control over their own actions. To do so, musicians dynamically shift between integrating other performers' actions into their own action plans and maintaining a distinction between their own and others' actions. Research in laboratory settings has shown that this dynamic process of self-other integration and distinction is indexed by sensorimotor alpha oscillations. The purpose of the current descriptive case study was to examine oscillations related to self-other integration and distinction in a naturalistic performance context. We measured alpha activity from four violinists during a concert hall performance of a 60-musician orchestra. We selected a musical piece from the orchestra's repertoire and, before analyzing alpha activity, performed a score analysis to divide the piece into sections that were expected to strongly promote self-other integration and distinction. In line with previous laboratory findings, performers showed suppressed and enhanced alpha activity during musical sections that promoted self-other integration and distinction, respectively. The current study thus provides preliminary evidence that findings from carefully controlled laboratory experiments generalize to complex real-world performance. Its findings also suggest directions for future research and potential applications of interest to musicians, music educators, and music therapists.

Singing for respiratory health: theory, evidence and challenges.

The premise that singing is a health promoting activity for people with respiratory conditions of chronic obstructive pulmonary disease (COPD) and asthma is a growing area of interest being investigated by researchers from various disciplines. The preliminary evidence, a theoretical framework and identification of methodological challenges are discussed in this perspective article with an eye to recommendations for further research to advance knowledge. After a brief summary of main research findings on singing in healthy people to provide background context, research is reviewed on singing in people with COPD and asthma. Studies include published research and as yet unpublished work by the authors. Methodological challenges arising from the reviewed studies are identified such as attrition from singing or control groups based on weak and strong, respectively, beliefs about singing's effectiveness. Potential solutions for these problems are considered with further recommendations made for other singing research.

Deaths from exposure to paramethoxymethamphetamine in Alberta and British Columbia, Canada: a case series.

BACKGROUND: Paramethoxymethamphetamine (PMMA) is a ring-substituted amphetamine similar in structure to 3,4-methylenedioxymethamphetamine (MDMA or "ecstasy"), but substantially more toxic. We describe the clinical features of fatal exposures in the provinces of Alberta and British Columbia, Canada. METHODS: We conducted a retrospective case series on deaths in Alberta and BC between June 2011 and April 2012 for which forensic toxicologic analysis was positive for PMMA and the drug was implicated as the primary toxic agent. Data collected included patient demographics, exposure history, clinical features, investigations, therapy provided and postmortem toxicologic findings. RESULTS: A total of 27 PMMA-associated deaths (20 in Alberta, 7 in BC) were reported in the 11-month period. The median age was 24 (range 14-52) years, and 22 (81%) were male. Ten patients were pronounced dead at the scene, and 17 died in hospital. The median time from exposure to death was 17 (range 5-264) hours. The median first-recorded vital signs (and ranges) were: heart rate 160 (86-201) beats/min, blood pressure 89/43 (69/30-162/83) mm Hg, respiratory rate 40 (26-48) breaths/min, oxygen saturation 81% (68%-100%) and temperature 39.4°C (34-43.8°C). Sixteen of the 17 people who died in hospital presented with clinical features consistent with serotonin syndrome. End-organ dysfunction included hepatic (30%) and acute kidney injury (85%), rhabdomyolysis (54%), coagulopathy (61%) and cardiac ischemia (15%). Other drugs identified on toxicologic analysis were MDMA (n = 27), cocaine or its metabolite benzoylecgonine (n = 14) and methamphetamine (n = 12). INTERPRETATION: Exposure to PMMA was characterized by multiorgan dysfunction and serotonin syndrome, followed by cardiovascular collapse. In addition to PMMA, multiple synthetic amphetamines were present on toxicologic analysis. When evaluating patients suspected of exposure to sympathomimetic drugs of abuse, clinicians must anticipate multiple clinical effects from the increased release of dopamine, serotonin, norepinephrine and other neurotransmitters.

RGD-dependent mechanisms in the endoneurial phagocyte response and axonal regeneration in the nervous system of the snail Lymnaea stagnalis.

Activation of phagocytic cells in the injury zone is a crucial step in the regeneration of peripheral axons. Many aspects of the mechanisms underlying the recruitment of active phagocytes remain, however, unclear. Notably, our understanding of the interactions between injury, extracellular matrix (ECM) degradation and phagocyte activation is limited. Most animal cell types, phagocytes included, interact with proteins of the ECM through one or more members of the integrin family, transmembrane cell adhesion receptors that typically bind their ligands through short linear amino acid sequences. This study focused on the role of one of the most common of such integrin recognition sequences, the Arg-Gly-Asp (RGD) motif in the recruitment and activation of endoneurial phagocytes in the injury response of the nervous system of the pond snail Lymnaea stagnalis. Like the mammalian nervous system, the Lymnaea nervous system responds to injury with recruitment and activation of endoneurial phagocytes (i.e. phagocytes residing in Lymnaea's nerves), a process involving substantial changes in the morphology, motility and adhesion status of these cells. Using synthetic water-soluble RGD-peptides, we investigated the relevance of RGD-dependent mechanisms in the activation of endoneurial phagocytes and injury response of the organ-cultured nervous system of Lymnaea. Our results show that RGD-peptides modulate various aspects of phagocyte activation (i.e. spreading response, particle engulfment, oxidative burst) in vitro and in situ and significantly affect nerve regeneration in this model system. Surprisingly, while linear RGD-analogues suppressed both phagocyte activation and axonal regeneration, a circularized RGD-peptide analogue modulated these parameters in a concentration-dependent, biphasic manner. Collectively, these results emphasize the significance of RGD-dependent mechanisms in the regenerative response of the Lymnaea nervous system and implicate regulation of the cellular immune response as one of the factors in this context.

Epidermal growth factor-dependent enhancement of axonal regeneration in the pond snail Lymnaea stagnalis: role of phagocyte survival.

Peripheral nerve injury triggers complex responses from neuronal as well as from multiple nonneuronal cell types. These responses are coordinated by a wide spectrum of secreted and nonsecreted factors, including growth factors, cytokines, and cell adhesion molecules. These molecules originate from different sources and act both locally at the site of injury as well as centrally at the location of the neuronal cell bodies. One of the signal systems frequently implicated in this process is the epidermal growth factor (EGF) family and its receptors. Expression of members of this family as well as that of EGF-receptors is upregulated in different cell types after peripheral nerve injury. However, the functional significance of this response is unclear. Using a simple invertebrate model system (Lymnaea stagnalis), the present study implicates the EGF/EGF-receptor system in the survival of ionized calcium-binding adaptor molecule 1 (Iba1)-positive phagocytes that reside in the nervous system. We show that inhibiting the EGF-signaling pathway enhances cell death in this type of cell, an effect paralleled by a substantial reduction in axonal regeneration. Therefore, complementing our previous observation that Lymnaea EGF provides trophic support to axotomized neurons, the present results emphasize the significance of nonneuronal actions of EGF receptor ligands in axonal regeneration. Thus, we add a novel perspective to the ongoing discussion on the functional significance of the EGF signaling system in the injury responses of the nervous system.