630 research outputs found

    A time-course analysis of changes in cerebral metal levels following a controlled cortical impact

    Full text link
    © 2016 The Royal Society of Chemistry. Traumatic brain injury (TBI) is complicated by a sudden and dramatic change in brain metal levels, including iron (Fe), copper (Cu) and zinc (Zn). Specific 'metallo-pathological' features of TBI include increased non-heme bound Fe and the liberation of free Zn ions, both of which may contribute to the pathogenesis of TBI. To further characterise the metal dyshomeostasis that occurs following brain trauma, we performed a quantitative time-course survey of spatial Fe, Cu and Zn distribution in mice receiving a controlled cortical impact TBI. Images of brain metal levels produced using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) in the upper quadrant of the ipsilateral hemisphere were compared to the corresponding contralateral hemisphere, together with regional areas radiating toward the center of the brain from the site of lesion. Significant regional and time point specific elevations in Fe, Zn and Cu were detected immediately and up to 28 days after TBI. The magnitude and timeframe of many of these changes suggest that TBI results in a pronounced and sustained alteration in normal metal levels within the brain. Such alterations are likely to play a role in both the short- and long-term consequences of head trauma and suggest that pharmacological modulation to normalize these metal levels may be efficacious in improving functional outcome

    Age modulates the injury-induced metallomic profile in the brain

    Full text link
    © 2017 The Royal Society of Chemistry. The biological transition metals iron (Fe), copper (Cu) and zinc (Zn) are thought to contribute to the neuronal pathologies that occur following traumatic brain injury (TBI), and indeed our previously published work in young (3 month-old) mice clearly demonstrates a significant spatiotemporal modulation of metals following TBI. Of note, however, is the literature observation that there is both an apparent detrimental effect of aging on TBI outcomes and an alteration in metals and their various transporters with normal advancing age. Therefore, to determine whether there was an interaction between aging, metals and TBI, we have utilised laser ablation-inductively coupled plasma-mass spectrometry to examine the spatial and temporal distribution of Fe, Zn and Cu following an acute controlled cortical impact brain injury in aged (24 months) rodents. The relative abundance of metals in corresponding regions within the ipsilateral and contralateral hemispheres as well as the hippocampus was assessed. Substantial region and time point specific alterations in Fe, Zn and Cu were identified immediately and up to 28 days post-TBI. The data from this follow-up study has also been compared to our previous data from young animals, and aged mice exhibit an appreciably enhanced and persistent elevation of all metals in every region surveyed, with individual metal disparities at various time points observed post-injury. This may potentially contribute to the acceleration in the onset of cognitive decline and neurological disease that has been observed in the aged population following head trauma

    Criminal and Noncriminal Psychopathy: The Devil is in the Detail

    Get PDF
    Brooks, NS ORCiD: 0000-0003-1784-099XPsychopathy is prevalent and problematic in criminal populations, but is also found to be present in noncriminal populations. In 1992, Robert Hare declared that psychopaths may also “be found in the boardroom”, which has since been followed by an interest in the issue of noncriminal, or even successful, psychopathy. In this chapter, the paradox of criminal and noncriminal psychopathy is discussed with specific attention given to the similarities and differences that account for psychopathic personality across contexts. That psychopathy is a condition typified by a constellation of traits and behaviours requires wider research across diverse populations, and thus the streams of research related to criminal and noncriminal psychopathy are presented and the implications of these contrasting streams are explored

    Predicting violent infractions in a Swiss state penitentiary: A replication study of the PCL-R in a population of sex and violent offenders

    Get PDF
    BACKGROUND: Research conducted with forensic psychiatric patients found moderate correlations between violence in institutions and psychopathy. It is unclear though, whether the PCL-R is an accurate instrument for predicting aggressive behavior in prisons. Results seem to indicate that the instrument is better suited for predicting verbal rather than physical aggression of prison inmates. METHODS: PCL-R scores were assessed for a sample of 113 imprisoned sex and violent offenders in Switzerland. Logistic regression analyses were used to estimate physical and verbal aggression as a function of the PCL-R sum score. Additionally, stratified analyses were conducted for Factor 1 and 2. Infractions were analyzed as to their motives and consequences. RESULTS: The mean score of the PCL-R was 12 points. Neither the relationship between physical aggression and the sum score of the PCL-R, nor the relationship between physical aggression and either of the two factors of the PCL-R were significant. Both the sum score and Factor 1 predicted the occurrence of verbal aggression (AUC=0.70 and 0.69), while Factor 2 did not. CONCLUSION: Possible explanations are discussed for the weak relationship between PCL-R scores and physically aggressive behavior during imprisonment. Some authors have discussed whether the low base rate of violent infractions can be considered an explanation for the non-significant relation between PCL-R-score and violence. The base rate in this study, however, with 27%, was not low. It is proposed that the distinction between reactive and instrumental motives of institutional violence must be considered when examining the usefulness of the PCL-R in predicting in-prison physical aggressive behavior

    Recognition memory, self-other source memory, and theory-of-mind in children with autism spectrum disorder.

    Get PDF
    This study investigated semantic and episodic memory in autism spectrum disorder (ASD), using a task which assessed recognition and self-other source memory. Children with ASD showed undiminished recognition memory but significantly diminished source memory, relative to age- and verbal ability-matched comparison children. Both children with and without ASD showed an “enactment effect”, demonstrating significantly better recognition and source memory for self-performed actions than other-person-performed actions. Within the comparison group, theory-of-mind (ToM) task performance was significantly correlated with source memory, specifically for other-person-performed actions (after statistically controlling for verbal ability). Within the ASD group, ToM task performance was not significantly correlated with source memory (after controlling for verbal ability). Possible explanations for these relations between source memory and ToM are considered

    Psychopathic traits and offender characteristics – a nationwide consecutive sample of homicidal male adolescents

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The aim of the study was to evaluate psychopathy-like personality traits in a nationwide consecutive sample of adolescent male homicide offenders and to compare the findings with those of a randomly sampled adult male homicide offender group. A further aim was to investigate associations between psychopathic traits and offender and offence characteristics in adolescent homicides.</p> <p>Methods</p> <p>Forensic psychiatric examination reports and crime reports of all 15 to19- year- old male Finnish offenders who had been subjected to a forensic psychiatric examination and convicted for a homicide during 1995–2004 were collected (n = 57). A random sample of 57 adult male homicide offenders was selected as a comparison group. Offence and offender characteristics were collected from the files and a file-based assessment of psychopathic traits was performed using the Hare Psychopathy Checklist-Revised (PCL-R) by trained raters.</p> <p>Results</p> <p>No significant differences existed between the adolescents and adults in PCL-R total scores, factor 2 (social deviance) scores, or in facets 3 (lifestyle) and 4 (antisocial). Adults scored significantly higher on factor 1 (interpersonal/affective) and facets 1 (interpersonal) and 2 (affective). The adolescent group was divided into two subgroups according to PCL-R total scores. One in five homicidal male adolescents met criteria for psychopathic personality using a PCL-R total score of 26 or higher. These boys significantly more often had a crime history before the index homicide, more frequently used excessive violence during the index homicide, more rarely lived with both parents until 16 years of age, had more institutional or foster home placements in childhood, had more school difficulties, more often had received special education, and, more often had contact with mental health services prior to age 18 years than boys scoring low on the PCL-R. They also more often had parental criminal history as well as homicide history of parents or near relatives than the group scoring low on the PCL-R.</p> <p>Conclusion</p> <p>Homicidal boys behaved as antisocially as the homicidal adults. The adults, however, showed more both affective and interpersonal features of psychopathy. Homicidal adolescents with psychopathy-like personality character form a special subgroup among other homicidal youngsters. Recognizing their characteristics, especially in life course development, would facilitate effective prevention and intervention efforts.</p

    Reading faces: differential lateral gaze bias in processing canine and human facial expressions in dogs and 4-year-old children

    Get PDF
    Sensitivity to the emotions of others provides clear biological advantages. However, in the case of heterospecific relationships, such as that existing between dogs and humans, there are additional challenges since some elements of the expression of emotions are species-specific. Given that faces provide important visual cues for communicating emotional state in both humans and dogs, and that processing of emotions is subject to brain lateralisation, we investigated lateral gaze bias in adult dogs when presented with pictures of expressive human and dog faces. Our analysis revealed clear differences in laterality of eye movements in dogs towards conspecific faces according to the emotional valence of the expressions. Differences were also found towards human faces, but to a lesser extent. For comparative purpose, a similar experiment was also run with 4-year-old children and it was observed that they showed differential processing of facial expressions compared to dogs, suggesting a species-dependent engagement of the right or left hemisphere in processing emotions

    Validity of the Modified Child Psychopathy Scale for Juvenile Justice Center Residents

    Get PDF
    Adult psychopathy has proven to be an important clinical and forensic construct, but much less is known about juvenile psychopathy. In the present study, we examined the construct validity of the self report modified Child Psychopathy Scale mCPS; Lynam (Psychological Bulletin 120:(2), 209–234, 1997) in a sample of 57 adolescents residing in a Dutch juvenile justice center, aged between 13 and 22 years. The mCPS total score was reliably related to high externalizing problems, low empathy, high anger and aggression, high impulsivity, high (violent) delinquency, and high alcohol/drug use. Unique relations were found for the antisocial-impulsive (mCPS Factor 2), but not the callous-unemotional facet of psychopathy (mCPS Factor 1). Our findings support the validity of the mCPS in that it encompasses the antisocial-impulsive facet of psychopathy, but it is less clear whether the mCPS sufficiently captures the affective-interpersonal facet of psychopathy

    Social modulation of contagious yawning in wolves

    Get PDF
    On the basis of observational and experimental evidence, several authors have proposed that contagious yawn is linked to our capacity for empathy, thus presenting a powerful tool to explore the root of empathy in animal evolution. The evidence for the occurrence of contagious yawning and its link to empathy, however, is meagre outside primates and only recently domestic dogs have demonstrated this ability when exposed to human yawns. Since dogs are unusually skilful at reading human communicative behaviors, it is unclear whether this phenomenon is deeply rooted in the evolutionary history of mammals or evolved de novo in dogs as a result of domestication. Here we show that wolves are capable of yawn contagion, suggesting that such ability is a common ancestral trait shared by other mammalian taxa. Furthermore, the strength of the social bond between the model and the subject positively affected the frequency of contagious yawning, suggesting that in wolves the susceptibility of yawn contagion correlates with the level of emotional proximity. Moreover, female wolves showed a shorter reaction time than males when observing yawns of close associates, suggesting that females are more responsive to their social stimuli. These results are consistent with the claim that the mechanism underlying contagious yawning relates to the capacity for empathy and suggests that basic building blocks of empathy might be present in a wide range of species
    corecore