Encephale
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The autonomic nervous system sends messages through the sympathetic and parasympathetic nervous system. The sympathetic nervous system innervates the cardioaccelerating center of the heart, the lungs (increased ventilatory rhythm and dilatation of the bronchi) and the non-striated muscles (artery contraction). It releases adrenaline and noradrenaline. As opposed to the sympathetic nervous system, it innervates the cardiomoderator center of the heart, the lungs (slower ventilatory rhythm and contraction of the bronchi) and the non-striated muscles (artery dilatation). It uses acetylcholine (ACh) as its neurotransmitter. Sympathetic and parasympathetic divisions function antagonistically to preserve a dynamic modulation of vital functions. These systems act on the heart respectively through the stellar ganglion and the vagus nerve. The interaction of these messages towards the sinoauricular node is responsible for normal cardiac variability, which can be measured by monitoring heart rate variability (HRV). Heart rate is primarily controlled by vagal activity. Sensorial data coming from the heart are fed back to the central nervous system. HRV is an indicator of both how the central nervous system regulates the autonomic nervous system, and of how peripheral neurons feed information back to the central level. HRV measures are derived by estimating the variation among a set of temporally ordered interbeat intervals. The state of perfect symmetry, which, in medical parlance, is called respiratory sinus arrhythmia (RSA), can be described as a state of cardiac coherence. Obtaining a series of interbeat intervals requires a continuous measure of heart rate, typically electrocardiography (ECG). Commercially available software is then used to define the interbeat intervals within an ECG recording. ⋯ The autonomic nervous system is highly adaptable and allows the organism to maintain its balance when experiencing strain or stress. Conversely, a lack of flexibility and a rigid system can lead to somatic and psychological pathologies. Several studies have shown a link between reduced HRV in postmyocardial infarction patients and increased risk for adverse cardiovascular events, including ventricular arrhythmias and sudden death. Recently, studies indicate that patients with depression and anxiety disorders exhibit abnormally low HRV compared with non-psychiatric controls. Reduced HRV seems indicate decreased cardiac vagal tone and elevated sympathetic activity in anxious and depressive patients and would reflect deficit in flexibility of emotional physiological mechanisms. A few studies have also revealed that biofeedback using respiratory control, relaxation and meditation techniques can increase HRV. For now, there is insufficient data to determine if paced respiration or subjective relaxation is necessary or sufficient for the efficacy of HRV biofeedback. Although the literature is modest, this review suggests that the use of biofeedback with relaxation and meditation approaches may result in increased HRV and parasympathetic activity. Limitations of the review literature have also been considered to identify areas for future research.
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During these two last decades, much research has shown that anxiety can be characterised by an attentional bias favouring threat stimuli processing. This bias plays a central role in the development and maintenance of pathological states associated with anxiety. The first part of this article concerns numerous variables that elucidate parts of the appearance and maintenance conditions of attentional bias associated with anxiety. Thus, clinical versus non-clinical states of individuals play an important role in attentional behaviour of anxiety: at an early stage of information processing, which involves mainly automatic processes, the attentional bias appears whatever the status of anxious individuals. At a later stage, which involves controlled processes, non-clinical anxious subjects would be able to use defensive strategies, which allow them to counterbalance the bias that appeared before, while clinical anxious subjects would not be able to ignore this threat, because of the major rooting of their anxiety. A vigilance attentional bias would be shown in clinical individuals throughout a continuum of information processing. In addition, a near unanimous observation highlights the importance of the material specificity in obtaining attentional bias. However, this observation appears less obvious for the subliminal condition in which anxious individuals can perfect a surface analysis of the material, identifying the emotional valence of a word and not its specificity. Literature findings on anxiety impact in order to release more clarity and in an attempt to explain empirical results that sometimes remain contradictory; the second part of this article is particularly focused on another research track, rarely used but very promising: it concerns differentiating the specific roles of anxiety state and anxiety trait in the attentional patterns. The anxiety trait is defined as "an acquired behavioural disposition, which predisposes an individual to perceive a whole of circumstances objectively and not as dangerous or threatening". On the other hand, anxiety state reflects variable component and is defined as an emotive state "characterized by subjective and conscious feelings of apprehension and tension associated with an activation of the autonomous nervous system". For a long time, researchers have mainly focused on this first variable while occulting the second. However, various theoretical models underline that the anxiety trait variable alone is certainly a condition necessary but insufficient in the appearance and maintenance of attentional bias. Thus, some empirical research, highlighting the potential role of the anxiety state was born. Although they have, for the moment, a limited range due to the heterogeneity of their results, these studies open a new route of considerable research. Thus, on the preattentive level, the dominant role of the interaction between anxiety state and anxiety trait in the release of bias was highlighted in a near consensual way. It is not the same at a later stage of information processing, which is a stage where two tracks of results are confronted: a part of research suggests that maintenance of bias is due to, as at the preattentive level, an interactive effect of state and trait anxieties, whereas other research shows a central role of anxiety state in maintenance of attentional bias. Recent studies using different paradigms confirm the idea of a central role of anxiety state. Further research, separating the specific roles of state and trait anxiety, will be necessary to decide clearly. ⋯ Various explanatory tracks were suggested to try to clear up these data. Thus, it's possible that the time-course of the stressor may be an important variable. In addition, the review highlights that state anxiety averages are too often far from the norms established by Spielberger et al. In short, if the state anxiety level is not sufficiently high in a number of searches, it then appears difficult to highlight the attentional biases, which are associated with it. Among them, the resort to a methodology combining physiological measurements (salivary index, ocular movements recording...) and cognitive measurements (questionnaires, dot probe paradigm, Stroop task...) seems to warrant a better understanding of attentional processes.
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Aripiprazole is an atypical antipsychotic with a pharmacological profile, different from other atypical antipsychotics. It is a high-affinity partial agonist at the dopamine D2 and serotonin 5-HT1A receptors and an antagonist at serotonin 5-HT2 receptors. It is associated with a good safety and tolerability profile including extrapyramidal side-effects. ⋯ We hypothesise that cytochrome P450 2D6 is implicated in this case-report because it is active in metabolizing aripiprazole. This patient could have been deficient in this enzyme, thus failing to metabolize aripiprazole at a normal rate.
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The aim of the study was to evaluate the incidence of depressive symptoms and suicidal ideation, and to test the mediating role of hopelessness between depressive symptoms and the wish to kill oneself. ⋯ These results showed a strong association between depressive symptoms and suicidal ideation in this nonclinical sample of adolescents. According to Beck's assumption, hopelessness appeared to be a mediator between depressive symptoms and the wish to kill oneself both in boys and girls. These findings are relevant for prevention and therapy. They suggest that targeting hopelessness may be as important in adolescents as in adults to reduce suicidal ideation and prevent suicidal attempts.