Experimentally Assessed Reactive Aggression in Borderline Personality Disorder

Approximately 73% of patients suffering from Borderline personality disorder (BPD) exhibit aggressive behaviour, which severely hinders therapeutic work and clinical improvement. Because the underlying mechanisms of aggression in BPD are not yet completely understood, additional research in this domain has a high clinical and scientific relevance. We employed a modified version of the Taylor Aggression Paradigm (mTAP), in order to examine for the first time whether this task can be used to differentiate between BPD patients and healthy controls with regard to reactive aggression. In the mTAP, the amount of money subtracted by a virtual opponent was categorized into ‘low’ (10–20 cents) and ‘high’ (80–100 cents) provocations, enabling us to compare how much money BPD patients and healthy controls subtracted (i.e., how aggressively participants responded) following high and low provocation trials. Our results showed that, compared to healthy controls, BPD patients showed higher overall aggression, higher aggression after high provocation trials, as well as a larger difference between high and low provocation trials. This finding was corroborated by a neuropsychological assessment, demonstrating higher levels of aggression and impulsivity in BPD patients. Interestingly, reactive aggression in the mTAP was positively correlated with symptom severity and impulsivity in BPD patients. We suggest that the mTAP provides a valuable tool allowing psychiatrists to quantify reactive aggression in BPD. Therefore, clinicians and researchers might consider this task, as a short experimental measure of reactive aggression, either in future studies or to aid diagnostic assessment during clinical practice

Relationship between reactive aggression and Borderline symptom severity and impulsivity.

<p>For the group of BPD patients, the figure visualizes the correlation (Pearson’s r) between reactive aggression (i.e., mean amount of money subtracted from the opponent during the mTAP), and the total scores of the Borderline personality inventory (BPI) and the Barratt Impulsiveness Scale (BIS-11). We found a significant positive correlation between reactive aggression and the BPI total score, which represents an overall indicator of BPD symptom severity, and between reactive aggression and the BIS-11 total score, which provides a reliable measure of impulsivity.</p

Emotional and effective changes following the modified Taylor Aggression Paradigm.

<p>Here, data from the State Trait Anger Expression Inventory (STAXI), Positive and Negative Affect Schedule (PANAS) and the subscale anger of the Emotional Self Rating (ESR) is shown. Pre and Post represent the time points immediately before and after the mTAP. Error bars represent standard error of the mean (SEM).</p

Differences in reactive aggression between BPD patients and healthy controls.

<p>Visualized are data from the modified Taylor Aggression Paradigm (mTAP), comparing the results of patients with Borderline personality disorder (BPD) and healthy controls (HC). Error bars represent standard deviation (SD). (A) The BPD group showed significantly higher aggression overall, which is represented by the money subtracted from the opponents. (B) The patients also had a significantly larger difference of subtractions when comparing trials following high provocation vs. trials following low provocation. (C) A significantly higher aggression following high provocation trials for BPD patients was also observed. (D) BPD patients also showed a numerically, but not significantly, higher aggression following low provocation trials.</p

On a fusion born triton effect in JET deuterium discharges with H-minority ion cyclotron range of frequencies heating

An effect due to fusion born triton production has been observed in JET high-performance deuterium plasma discharges with neutral beam injection (NBI) and H-minority ion cyclotron range of frequencies (ICRF) heating, using DD and deuterium tritium (DT) neutron spectrometry as well as fusion product loss measurements. The observations show that a decrease of the second harmonic omega = 2 omega(cD) enhancement of the DD neutron rate correlates with an increase of the triton burnup rate. An acceleration of tritons due to absorbing ICRH power at the third harmonic omega = 3 omega(cT) has been observed. This effect could indicate a redistribution of ICRH power absorption at omega approximate to omega(cH) = 2 omega(cD) = 3 omega(cT) with increasing triton concentration at the ion cyclotron resonance layer. Also, the reduction of the second harmonic enhancement of the DD neutron rate can be caused by burning of the accelerated deuterium as the tritium concentration grows. This is an extremely non-linear process as both mechanisms intensify with triton concentration. It determines the necessity to consider the ICRH power absorption omega = 3 omega(cT) in modelling of high-performance deuterium discharges with simultaneous NBI and H-minority ICRF heating as well as the assessment of enhanced burnup of ICRF accelerated deuterium for the development of high-performance plasma scenarios and DT fusion rate predictions

Escaping alpha-particle monitor for burning plasmas

This paper presents a diagnostic system, gamma-ray alpha-particle monitor (GRAM), for continuous monitoring of deuterium-tritium fusion alpha-particles in the MeV energy range escaped from the plasma to the first wall. The diagnostic is based on the detection of gamma-rays produced in nuclear reactions. The reactions Be-9(alpha,eta,gamma)C-12 and B-10(alpha,p,gamma)C-13 have been selected. For that purpose, Be- or B-10-target is placed on the first wall, where the alphas are expected to be mostly lost. Striking the target, the lost alphas generate specific gamma-rays, if their energy E-alpha > 1.5 MeV. To measure this gamma-ray emission, the target should be in the field of view of a collimated detector, which is protected from neutrons and background gammas. The calibrated detector could deliver absolute values of the lost alpha-particle flux with a temporal resolution depending on intensity of losses. A high-performance gamma-ray spectrometer with a novel architecture, GRITER, is proposed to be used in GRAM. It consists of a stack of the optically isolated high-Z fast scintillators with independent signal readout. GRITER is supposed to be operated at count-rates substantially exceeding the capability of a single crystal detector of the same size. The GRAM diagnostic system consists of two identical spectrometers, which measure both gamma-rays due to alpha-particle loss and gamma-ray background ensuring reliable data in a harsh reactor environment. GRAM could be tested during the non-DT plasma operation monitoring lost DD fusion products, neutral beam heating D-ions (E-D > 0.5 MeV) and ICRF accelerated H- and He-3-ions through the detection of gamma-rays resulting from nuclear reactions. The use of GRAM on JET and ITER, including events with extremely high loss rates, is discussed

Evidence of 9Be + p nuclear reactions during 2ω CH and hydrogen minority ICRH in JET-ILW hydrogen and deuterium plasmas

The intensity of 9Be + p nuclear fusion reactions was experimentally studied during second harmonic (2ω CH) ion-cyclotron resonance heating (ICRH) and further analyzed during fundamental hydrogen minority ICRH of JET-ILW hydrogen and deuterium plasmas. In relatively low-density plasmas with a high ICRH power, a population of fast H+ ions was created and measured by neutral particle analyzers. Primary and secondary nuclear reaction products, due to 9Be + p interaction, were observed with fast ion loss detectors, γ-ray spectrometers and neutron flux monitors and spectrometers. The possibility of using 9Be(p, d)2α and 9Be(p, α)6Li nuclear reactions to create a population of fast alpha particles and study their behaviour in non-active stage of ITER operation is discussed in the paper