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Idiopathic inflammatory myopathies are a heterogeneous group of rare autoimmune disorders characterized by progressive muscle weakness and the histopathologic findings of inflammatory infiltrates in muscle tissue. Although their pathogenesis remains indefinite, the association of autoantibodies with clinical manifestations and the evidence of high effectiveness of depleting therapies suggest that B cells could be implicated. Therefore, we explored the landscape of peripheral B cells in this disease by multiparametric flow cytometry, finding significant numerical decreases in memory and double-negative subsets, as well as an expansion of the naive compartment relative to healthy controls, that contribute to defining disease-associated B-cell subset signatures and correlating with different clinical features of patients. Additionally, we determined the potential value of these subsets as diagnostic biomarkers, thus positioning B cells as neglected key elements possibly participating in idiopathic inflammatory myopathy onset or development.

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Introduction: Decision-making is a process that can be strongly affected by social factors. Evidence has shown how people deviate from traditional rational-choice predictions under different levels of social interactions. The emergence of prosocial decision-making, defined as any action that is addressed to benefit another individual even at the expense of personal benefits, has been reported as an example of such social influence. Furthermore, brain evidence has shown the involvement of structures such as the prefrontal cortex, anterior insula, and midcingulate cortex during decision settings in which a decision maker interacts with others under physical pain or distress or while being observed by others. Methods: Using a slightly modified version of the dictator game and EEG recordings, we tested the hypothesis that the inclusion of another person into the decision setting increases prosocial decisions in young adults and that this increase is higher when the other person is associated with others in need. At the brain level, we hypothesized that the increase in prosocial decisions correlates with frontal theta activity. Results and Discussion: The results showed that including another person in the decision, setting increased prosocial behavior only when this presence was associated with someone in need. This effect was associated with an increase in frontocentral theta-oscillatory activity. These results suggest that the presence of someone in need enhances empathy concerns and norm compliance, raising the participants' prosocial decision-making.

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Anticipating social stress evokes strong reactions in the organism, including interoceptive modulations. However, evidence for this claim comes from behavioral studies, often with inconsistent results, and relates almost solely to the reactive and recovery phase of social stress exposure. Here, we adopted an allostatic-interoceptive predictive coding framework to study interoceptive and exteroceptive anticipatory brain responses using a social rejection task. We analyzed the heart-evoked potential (HEP) and task-related oscillatory activity of 58 adolescents via scalp EEG, and 385 human intracranial recordings of three patients with intractable epilepsy. We found that anticipatory interoceptive signals increased in the face of unexpected social outcomes, reflected in larger negative HEP modulations. Such signals emerged from key brain allostatic-interoceptive network hubs, as shown by intracranial recordings. Exteroceptive signals were characterized by early activity between 1-15 Hz across conditions, and modulated by the probabilistic anticipation of reward-related outcomes, observed over distributed brain regions. Our findings suggest that the anticipation of a social outcome is characterized by allostatic-interoceptive modulations that prepare the organism for possible rejection. These results inform our understanding of interoceptive processing and constrain neurobiological models of social stress.

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Autonomous sensory meridian response (ASMR) describes the experience of a pleasant body sensation accompanied by a feeling of well-being and relaxation in response to specific audiovisual stimuli, such as whispers and personal attention. Previous work suggests a relationship between this experience with the processing of affective and body states; however, no research has explored differences in interoception between people experiencing ASMR and those who do not. We hypothesized that the ASMR experience is based on interoception processing. To test this, we assessed group differences across different dimensions of interoception: Interoceptive sensibility (IS), measured using the multidimensional assessment of interoceptive awareness (MAIA); Interoceptive accuracy score (IAS), measured by calculating performance in a heartbeat counting task (HCT), and the electrophysiological index of interoception, the heartbeat evoked potential (HEP), which was calculated during the HCT and an ASMR tingle reporting task (ASMR-TRT). Our results showed that IS and IAS, dimensions requiring conscious awareness, showed no differences between groups. However, HEP amplitude was larger in the ASMR group in both tasks. We concluded that the ASMR experience is based on an unconscious interoceptive mechanism, reflected by HEP, where exteroceptive social-affective stimuli are integrated to represent a body state of positive affective feelings and relaxation, as has been described for affective touch. The relevance of this finding relies on that interoceptive function, body regulation, and emotional/affective experiences are fundamental for well-being, and the relationship between ASMR and interoception opens the way to future research exploring the causal relationship between them and their potential clinical applications.

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Attention deficit/hyperactivity disorder (ADHD) is a heterogeneous neurodevelopmental condition, that continues to have an elusive etiological background. A number of extant models and theories have historically intended to explain the many factors contributing to ADHD behaviors. One of the most accepted hypotheses has been the executive dysfunction theory associating reduction in executive control to abnormalities in structure and operational dysfunction of dopaminergic signaling networks. Nevertheless, executive functions are not always impaired in ADHD, and the literature describes other symptoms commonly reported suggesting individuals with ADHD would appear to suffer from a more general deficit. Another existing line of research, that has gained much attention recently, establishes that ADHD would have dysregulated states of brain arousal that would account for its commonly observed cognitive deficits and behavioral symptoms, described as the state regulation theory, which has now included measures of autonomic function. This article describes some important aspects that compose and challenge these two most influential theoretical constructs, executive dysfunction and state-regulation, based on their empirical evidence, implying the need to reevaluate the norms used to classify individuals and establish ADHD diagnosis. Large number of controversial results continue to exist within the study of ADHD biological and/or performance markers, possibly due to such heterogeneity and variability within the same diagnosis. The need to resolve these issues and establish newly revised diagnostic criteria for ADHD is critical, as therapeutic success depends on having accurately identified underlying neurophysiological factors in order to appropriately address them in treatment.

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Incidental findings are not uncommon in echocardiography. A transthoracic echocardiogram (TTE) of an adult woman with arterial hypertension showed a tubular structure with hyperechoic walls in the atrial side of the atrioventricular groove in apical views. Coronary computed tomography angiography correlated this finding with a retroaortic course of the anomalous circumflex artery (retroaortic anomalous coronary artery [RAC], benign coronary artery variant). Recently described as the RAC sign on TTE, practitioners should be aware of this finding to avoid mistaken it as artifacts, catheters/leads, or calcified mitral annulus.

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Top-down modulation of sensory responses to distracting stimuli by selective attention has been proposed as an important mechanism by which our brain can maintain relevant information during working memory tasks. Previous works in visual working memory (VWM) have reported modulation of neural responses to distracting sounds at different levels of the central auditory pathways. Whether these modulations occur also at the level of the auditory receptor is unknown. Here, we hypothesize that cochlear responses to irrelevant auditory stimuli can be modulated by the medial olivocochlear system during VWM. Twenty-one subjects (13 males, mean age 25.3 yr) with normal hearing performed a visual change detection task with different VWM load conditions (high load = 4 visual objects; low load = 2 visual objects). Auditory stimuli were presented as distractors and allowed the measurement of distortion product otoacoustic emissions (DPOAEs) and scalp auditory evoked potentials. In addition, the medial olivocochlear reflex strength was evaluated by adding contralateral acoustic stimulation. We found larger contralateral acoustic suppression of DPOAEs during the visual working memory period (n = 21) compared with control experiments (n = 10), in which individuals were passively exposed to the same experimental conditions. These results show that during the visual working memory period there is a modulation of the medial olivocochlear reflex strength, suggesting a possible common mechanism for top-down filtering of auditory responses during cognitive processes.NEW & NOTEWORTHY The auditory efferent system has been proposed to function as a biological filter of cochlear responses during selective attention. Here, we recorded electroencephalographic activity and otoacoustic emissions in response to auditory distractors during a visual working memory task in humans. We found that the olivocochlear efferent activity is modulated during the visual working memory period suggesting a common mechanism for suppressing cochlear responses during selective attention and working memory.

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The human brain generates predictions about future events. During face-to-face conversations, visemic information is used to predict upcoming auditory input. Recent studies suggest that the speech motor system plays a role in these cross-modal predictions, however, usually only audio-visual paradigms are employed. Here we tested whether speech sounds can be predicted on the basis of visemic information only, and to what extent interfering with orofacial articulatory effectors can affect these predictions. We registered EEG and employed N400 as an index of such predictions. Our results show that N400's amplitude was strongly modulated by visemic salience, coherent with cross-modal speech predictions. Additionally, N400 ceased to be evoked when syllables' visemes were presented backwards, suggesting that predictions occur only when the observed viseme matched an existing articuleme in the observer's speech motor system (i.e., the articulatory neural sequence required to produce a particular phoneme/viseme). Importantly, we found that interfering with the motor articulatory system strongly disrupted cross-modal predictions. We also observed a late P1000 that was evoked only for syllable-related visual stimuli, but whose amplitude was not modulated by interfering with the motor system. The present study provides further evidence of the importance of the speech production system for speech sounds predictions based on visemic information at the pre-lexical level. The implications of these results are discussed in the context of a hypothesized trimodal repertoire for speech, in which speech perception is conceived as a highly interactive process that involves not only your ears but also your eyes, lips and tongue.

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Abstract In Colombia there are no guidelines for diagnosis and management of patients with short stature and for the use of recombinant human growth hormone, mainly caused by the diversity of training centers in pediatric endocrinology. In response to this situation, the Asociación Colegio Colombiana de Endocrinología Pediátrica leds the first colombian short stature expert committee in order to standardize the use of human recombinant growth hormone. This work had the participation and endorsement of a consortium of clinical experts representing the Sociedad Colombiana de Pediatría, Secretaría Distrital de Salud de Bogotá- Subred Integrada de Servicios de Salud Suroccidente, Fundación Universitaria Sanitas, Universidad de los Andes and some public and private health institutions in the country, in addition to the participation of methodological experts from the Instituto Global de Excelencia Clínica Keralty. By reviewing the literature and with the best available evidence, we proposed to unify definitions, a diagnostic algorithm, biochemical and dynamic tests with their reference parameters, a description of the considerations about growth hormone use among the indications approved by regulatory agency for medications and food in Colombia and finally a proposal for an informed consent and a medication fact sheet available for parents and patients.

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Working memory (WM) impairments in ADHD have been consistently reported along with deficits in attentional control. Yet, it is not clear which specific WM processes are affected in this condition. A deficient coupling between attention and WM has been reported. Nevertheless, most studies focus on the capacity to retain information rather than on the attention-dependent stages of encoding and retrieval. The current study uses a visual short-term memory binding task, measuring both behavioral and electrophysiological responses to characterize WM encoding, binding and retrieval comparing ADHD and non-ADHD matched adolescents. ADHD exhibited poorer accuracy and larger reaction times than non-ADHD on all conditions but especially when a change across encoding and test displays occurred. Binding manipulation affected equally both groups. Encoding P3 was larger in the non-ADHD group. Retrieval P3 discriminated change only in the non-ADHD group. Binding-dependent ERP modulations did not reveal group differences. Encoding and retrieval P3 were significantly correlated only in non-ADHD. These results suggest that while binding processes seem to be intact in ADHD, attention-related encoding and retrieval processes are compromised, resulting in a failure in the prioritization of relevant information. This new evidence can also inform recent theories of binding in visual WM.

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