Asylum-seeking children in shutdown: Neurobiological models

Asylum-seeking children presenting in the shutdown state have been the subject of much discussion and controversy—on both government and medical system levels—in Australia and in Sweden. In this article, we conceptualize the shutdown state as an evolutionary response to extreme threat. We adopt a neuroscience approach to present five plausible models for explaining this shutdown state, their strengths and shortcomings, and the overlaps between them. Model 1—the sustained autonomic arousal model—draws on polyvagal theory. Model 2—the innate-defence model—draws on research pertaining to animal and human innate defence responses. Model 3—the catatonia model—draws on clinical and research data with patients presenting with catatonia. Model 4—the hypometabolic model—draws on an emerging body of work pertaining to hypometabolic states in animals and humans. Model 5—the defence cascade model of dissociation—draws on clinical research pertaining to human trauma states that present as dissociation. At present, each of the models provides a plausible pathophysiological explanation—or a component of a potential pathophysiological explanation—and none of them, for the moment, has enough evidence to be either accepted or disregarded. We hope that our discussion of the models advances scientific discussion and opens up possibilities for effective treatment.

Hunting dogs bark differently when they encounter different animal species

Previous studies have shown that vocalizations of dogs can provide information to human companions. While acoustic signals of dogs have been intensively studied during the last decade, barking during hunting activities remains unstudied. The experiences of hunters indicate that owners can recognize what animal species has been found based on the bark of their dog. Such a phenomenon has never been tested before. We tested such an ability by comparing barks that were produced when dogs encountered four different animal species: wild boar, red fox, rabbit and fowl. Classification results of a discrimination analysis showed, that based on barks of dachshunds and terriers, it is possible to categorize towards which animal species barks were produced. The most distinctive barks were produced during encounters with the most dangerous of these animals, the wild boar. On the contrary, barks evoked by red fox encounters were classified similarly as those towards other smaller and non-dangerous animals like rabbits and fowl. Although the red fox represents a potentially dangerous species, the barking provoked was not classified with a much higher result than barking at animals that pose no threat. This might indicate that the key parameter could be the body size of the animal the dog meets. We further tested whether the degree of threat from the species of animal the dog encounters is reflected in the structure of the acoustic parameters based on the valence-arousal model. We found that barks produced in contact with a wild boar showed significantly lower frequency parameters and longest duration compared to other barks. According to these results, it seems that the variability of barking depending on the species of animal a dog encounters is an expression of the dogʼs inner state rather than functionally reference information.

Associations of Hyperactivity and Inattention Scores with Theta and Beta Oscillatory Dynamics of EEG in Stop-Signal Task in Healthy Children 7–10 Years Old

In the current study, we aimed to investigate the associations between the natural variability in hyperactivity and inattention scores, as well as their combination with EEG oscillatory responses in the Stop-Signal task in a sample of healthy children. During performance, the Stop-Signal task EEGs were recorded in 94 Caucasian children (40 girls) from 7 to 10 years. Hyperactivity/inattention and inattention scores positively correlated with RT variability. Hyperactivity/inattention and inattention scores negatively correlated with an increase in beta spectral power in the first 200 ms after presentation of the Go stimulus. Such results are in line with the lack of arousal model in ADHD children and can be associated with less sensory arousal in the early stages of perception in children with symptoms of inattention. The subsequent greater increase in theta rhythm at about 300 ms after presentation of the Go stimulus in children with higher inattention scores may be associated with increased attention processes and compensation for insufficient vigilance in the early stages of perception.

Visual exploration in adults: Habituation, mere exposure, or optimal level of arousal?

Exploration is one of the most powerful behaviours that drive learning from infancy to adulthood. The aim of the current study was to examine the role of novelty and subjective preference in visual exploration. To do this, we combined a visual exploration task with a subjective evaluation task, presenting novel and familiar pictures. The first goal was to ascertain whether, as demonstrated in babies, short habituation favors visual exploration of familiarity, whereas longer habituation leads to an exploration of novelty. The second goal was to evaluate the influence of familiarization on participants’ subjective evaluation of the stimuli. When presented with novel and very familiar stimuli, participants explored the novel stimuli more. In line with the optimal-level of arousal model, participants showed more positive evaluations of the semi-familiar stimuli compared with very familiar or very novel ones.

Transgender and Gender Nonconforming Youths’ Emotions: The Appraisal, Valence, Arousal Model

Increased scientific understanding explains why transgender and gender nonconforming (TGNC) youth report more mental health concerns than their cisgender peers. However, the emotional processes of TGNC youth have not been assessed beyond mental health diagnoses. Our aim in this study was to investigate how TGNC youth understand, experience, and label their emotional experiences. We conduced a two-tiered qualitative analysis of 20 predominantly White TGNC youths, ages 7–18 years, resulting in the creation of the appraisal, valence, arousal theory of emotions. Within the theory, emotions are categorized in four quadrants: Reflective/Unpleasant, Anticipatory/Unpleasant, Reflective/Pleasant, and Anticipatory/Pleasant. Results indicated that the majority of TGNC youths’ emotions were located in the Reflective/Unpleasant and Reflective/Pleasant quadrants. The current study highlights TGNC youths’ appraisal of emotions and the potential impact on youths’ cognitive and emotional processes. Interventions should attend to pleasant and unpleasant aspects of emotions while also focusing on youths’ understanding of the context of their emotions.

Continuous regimens of cortico-motor integration calibrate levels of arousal during emergence from anesthesia

BackgroundRecovery to a conscious state when emerging from anesthesia requires full cortical desynchronization, initiation of movement and behavioral reactivity to sensory stimuli. However, the variety of cortical electroencephalogram (EEG) patterns associated with specific anesthetics and the paucity of behavioral descriptions during emergence from anesthesia have prevented EEG and behavior as feasible tracking methods to assess emerging from anesthesia. We propose a detailed combined analysis of motor and cortical activity to determine levels of arousal in rodents.MethodsUsing decreasing anesthetic concentrations, we simultaneously recorded local field potentials (LFPs) and movement in mice. We delineated cortical dynamics and sub-states during emergence from anesthesia by applying a smoothed-Z score to extract dominant frequencies from spectrogram. Then, we implemented KMeans to obtain cortical sub-states. Finally, we used density estimation and an abrupt change detection algorithm to segment cortical activity into periods. We used cortical sub-states obtained during isoflurane traces to supervise sub-states in sevoflurane and a pharmacologically induced-arousal model. This information together with examining videos were used to categorize behavior.ResultsWe identified five cortical periods with restored motor behavior during emergence from isoflurane anesthetic. Periods of structured sub-states denoted when specific motor behaviors occurred. No significant differences were found when comparing the combined cortical features and motor behavior using isoflurane, sevoflurane and our arousal-rodent model. We describe graded regimens of cortico-motor activity during emergence from anesthesia to assess arousal levels.ConclusionWe show cortical patterns denote gradual motor behaviors when emerging from anesthesia. Restoring motor behavior is a dynamic process that begins tens of minutes earlier than the righting reflex. Combining cortical activity and motor behavior unveils novel biomarkers to accurately track emerging from general anesthesia in rodents and likely other species.

Comparing three models of arousal in the human brain

The bipolar valence–arousal model is assumed by many to be an underlying structure of conscious experience of core affect and emotion. In this work, we compare three versions of the bipolar valence–arousal model at the neural domain, using functional magnetic resonance imaging (fMRI). Specifically, we systematically contrast three models of arousal: model 1—‘arousal as a separate quale from valence’, model 2—‘arousal as intensity of bipolar valence’ and model 3—‘arousal as a linear combination of unipolar pleasant and unpleasant’. Using parametric modulation analysis, we estimated the ability of each model to predict activation in arousal-related brain regions, in response to affective stimuli. The results suggest that arousal is not separable from valence in its ability to predict arousal-related neural activity. The relevance of the results to the theory of conscious affect is discussed.

Portuguese Version of the Posttraumatic Stress Disorder Checklist for DSM-5 (PCL-5): Comparison of Latent Models and Other Psychometric Analyses

<p>The PCL (Weathers et al., 1993) is a useful and widely used measure to assess PTSD symptoms in clinical and research contexts, exhibiting adequate psychometric properties across its several versions and translations (e. g. Carvalho et al., 2015; Wilkins et al., 2011). The current study analyzed the psychometric properties (latent structure, internal consistency, temporal reliability, and convergent validity) of the Portuguese version of the PCL for the DSM-5 (PCL-5, Weathers et al., 2013) in a sample of firefighters. This study also aimed to contribute with empirical data to clarify the best latent structure of DSM-5 PTSD symptoms. Specifically, the DSM-5 four-factor model and other competing models for PTSD symptoms (four-factor Dysphoria model, five-factor Dysphoric Arousal model, six-factor Anhedonia model, six-factor Externalizing Behavior model, and seven-factor Hybrid model) applied to PCL-5 were analyzed and compared in this paper.<br></p>