493 research outputs found

    Evaluating Methods of Correcting for Multiple Comparisons Implemented in SPM12 in Social Neuroscience fMRI Studies: An Example from Moral Psychology

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    In fMRI research, the goal of correcting for multiple comparisons is to identify areas of activity that reflect true effects, and thus would be expected to replicate in future studies. Finding an appropriate balance between trying to minimize false positives (Type I error) while not being too stringent and omitting true effects (Type II error) can be challenging. Furthermore, the advantages and disadvantages of these types of errors may differ for different areas of study. In many areas of social neuroscience that involve complex processes and considerable individual differences, such as the study of moral judgment, effects are typically smaller and statistical power weaker, leading to the suggestion that less stringent corrections that allow for more sensitivity may be beneficial, but also result in more false positives. Using moral judgment fMRI data, we evaluated four commonly used methods for multiple comparison correction implemented in SPM12 by examining which method produced the most precise overlap with results from a meta-analysis of relevant studies and with results from nonparametric permutation analyses. We found that voxel-wise thresholding with family-wise error correction based on Random Field Theory provides a more precise overlap (i.e., without omitting too few regions or encompassing too many additional regions) than either clusterwise thresholding, Bonferroni correction, or false discovery rate correction methods

    Cortisol, Testosterone, and Alpha-Amylase in Psychopathy

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    A recently developed theory suggests that imbalances in hormone systems may contribute to psychopathy (van Honk & Schutter, 2006). Researchers have begun to emphasize the interconnectedness of hormone systems, and recommend examining multiple systems simultaneously in order to examine potential interactions. Very few studies have examined the role of hormones in psychopathy and results have been mixed, possibly due to the examination of only one hormone at a time. In a sample of 178 adults from the community demonstrating a wide range of psychopathy scores, I examine the relationship between psychopathy and two hormones and one enzyme that have been theoretically linked to psychopathy – cortisol, testosterone, and alpha-amylase. In Section 1, I focus on cortisol and testosterone – the end products of two hormonal axes that work together to maintain an appropriate balance between withdrawing in the presence of fearful or threatening stimuli, and approaching in the presence of reward – the hypothalamus-pituitary-adrenal (HPA) axis and the hypothalamus-pituitary-gonadal (HPG) axis. Psychopathy is associated with an apparent imbalance in these processes, as it is characterized by reduced fearfulness, insensitivity to punishment, reward-seeking, and aggression (Hare, 2003). Psychopathy was not associated with cortisol or testosterone measures individually, but was associated with the ratio between baseline testosterone levels and cortisol reactivity to a stressor. In Section 2, I focus on cortisol and alpha-amylase – indicators of the two primary components of the stress response system – the HPA axis and the sympathetic nervous system. Researchers have hypothesized that deficits in this system contribute to the fearlessness and insensitivity to punishment observed in psychopathy, but the relative contribution of the two components, or how they may interact, has not been explored. Psychopathy was not associated with cortisol or alpha-amylase measures individually. However, an interaction was observed indicating that at high levels of alpha-amylase, cortisol was negatively associated with psychopathy. Overall, these results support the hypothesis that psychopathy is associated with an altered balance between highly interconnected hormone systems, and emphasize the importance of examining multiple systems simultaneously

    Psychopathy and instrumental aggression: Evolutionary, neurobiological, and legal perspectives

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    In the study of aggression, psychopathy represents a disorder that is of particular interest because it often involves aggression which is premeditated, emotionless, and instrumental in nature; this is especially true for more serious types of offenses. Such instrumental aggression is aimed at achieving a goal (e.g., to obtain resources such as money, or to gain status). Unlike the primarily reactive aggression observed in other disorders, psychopaths appear to engage in aggressive acts for the purpose of benefiting themselves. This is especially interesting in light of arguments that psychopathy may represent an alternative life-history strategy that is evolutionarily adaptive; behaviors such as aggression, risk-taking, manipulation, and promiscuous sexual behavior observed in psychopathy may be means by which psychopaths gain advantage over others. Recent neurobiological research supports the idea that abnormalities in brain regions key to emotion and morality may allow psychopaths to pursue such a strategy—psychopaths may not experience the social emotions such as empathy, guilt, and remorse that typically discourage instrumentally aggressive acts, and may even experience pleasure when committing these acts. Findings from brain imaging studies of psychopaths may have important implications for the law

    Neurocriminology: Implications for the Punishment, Prediction and Prevention of Criminal Behaviour

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    Criminal behaviour and violence are increasingly viewed as worldwide public health problems. A growing body of knowledge shows that criminal behaviour has a neurobiological basis, and this has intensified judicial interest in the potential application of neuroscience to criminal law. It also gives rise to important questions. What are the implications of such application for predicting future criminal behaviour and protecting society? Can it be used to prevent violence? And what are the implications for the way offenders are punished

    Associations between psychopathic traits and brain activity during instructed false responding

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    Lying is one of the characteristic features of psychopathy, and has been recognized in clinical and diagnostic descriptions of the disorder, yet individuals with psychopathic traits have been found to have reduced neural activity in many of the brain regions that are important for lying. In this study, we examine brain activity in sixteen individuals with varying degrees of psychopathic traits during a task in which they are instructed to falsify information or tell the truth about autobiographical and non-autobiographical facts, some of which was related to criminal behavior. We found that psychopathic traits were primarily associated with increased activity in the anterior cingulate, various regions of the prefrontal cortex, insula, angular gyrus, and the inferior parietal lobe when participants falsified information of any type. Associations tended to be stronger when participants falsified information about criminal behaviors. Although this study was conducted in a small sample of individuals and the task used has limited ecological validity, these findings support a growing body of literature suggesting that in some contexts, individuals with higher levels of psychopathic traits may demonstrate heightened levels of brain activity

    Developmental Level of Moral Judgment Influences Behavioral Patterns during Moral Decision-making

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    We developed and tested a behavioral version of the Defining Issues Test-1 revised (DIT-1r), which is a measure of the development of moral judgment. We conducted a behavioral experiment using the behavioral Defining Issues Test (bDIT) to examine the relationship between participants’ moral developmental status, moral competence, and reaction time when making moral judgments. We found that when the judgments were made based on the preferred moral schema, the reaction time for moral judgments was significantly moderated by the moral developmental status. In addition, as a participant becomes more confident with moral judgment, the participant differentiates the preferred versus other schemas better particularly when the participant’s abilities for moral judgment are more developed

    Measuring Moral Reasoning using Moral Dilemmas: Evaluating Reliability, Validity, and Differential Item Functioning of the Behavioral Defining Issues Test (bDIT)

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    We evaluated the reliability, validity, and differential item functioning (DIF) of a shorter version of the Defining Issues Test-1 (DIT-1), the behavioral DIT (bDIT), measuring the development of moral reasoning. 353 college students (81 males, 271 females, 1 not reported; age M = 18.64 years, SD = 1.20 years) who were taking introductory psychology classes at a public University in a suburb area in the Southern United States participated in the present study. First, we examined the reliability of the bDIT using Cronbach’s α and its concurrent validity with the original DIT-1 using disattenuated correlation. Second, we compared the test duration between the two measures. Third, we tested the DIF of each question between males and females. Findings reported that first, the bDIT showed acceptable reliability and good concurrent validity. Second, the test duration could be significantly shortened by employing the bDIT. Third, DIF results indicated that the bDIT items did not favour any gender. Practical implications of the present study based on the reported findings are discussed

    Psychopathy and Free Will From a Philosophical and Cognitive Neuroscience Perspective

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    In our chapter, we discuss one of the most influential compatibilist accounts of free will, Fischer and Ravizza\u27s (1998) reasons-responsiveness theory, and review the empirical literature on psychopathy that addresses the requirements for moral responsibility that are put forward in their account. Reasons-responsive compatibilist views seem to argue for the absence of moral responsibility or at least diminished responsibility when considering psychopathy. Their view draws upon impairments in the relevant kind of reasons-responsiveness in which one is responsive to both prudential and moral reasons. If moral reasons as genuine reasons that may motivate behavior are somehow aliento individuals with psychopathy, can we argue that these individuals are fully responsible for their immoral behavior? Based on empirical findings, we argue that psychopaths have core affective and cognitive deficits that may impair moral rationality. We conclude that the hard determinist, hard incompatibilist, and reasons-responsive compatibilist view suggest that offenders with severe psychopathy should not be held criminally responsible, and that mild psychopathy should function as a mitigating factor allowing for partial criminal responsibility. We should greatly increase our emphasis on early prevention and rehabilitation while ensuring that society is adequately protected and the feelings and rights of victims are respected. What we fear – or at any rate a very important part of what we fear – in determinism is the prospect that determinism would rule out control, and we very definitely do not want to lose control or be out of control or be controlled by something or someone else – like a marionette or puppet. (Dennett, 1984: 51

    CALIFA reveals Prolate Rotation in Massive Early-type Galaxies: A Polar Galaxy Merger Origin?

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    We present new evidence for eight early-type galaxies (ETGs) from the CALIFA Survey that show clear rotation around their major photometric axis ("prolate rotation"). These are LSBCF560-04, NGC 0647, NGC 0810, NGC 2484, NGC 4874, NGC 5216, NGC 6173 and NGC 6338. Including NGC 5485, a known case of an ETG with stellar prolate rotation, as well as UGC 10695, a further possible candidate for prolate rotation, we report ten CALIFA galaxies in total that show evidence for such a feature in their stellar kinematics. Prolate rotators correspond to ~9% of the volume-corrected sample of CALIFA ETGs, a fraction much higher than previously reported. We find that prolate rotation is more common among the most massive ETGs. We investigate the implications of these findings by studying N-body merger simulations, and show that a prolate ETG with rotation around its major axis could be the result of a major polar merger, with the amplitude of prolate rotation depending on the initial bulge-to-total stellar mass ratio of its progenitor galaxies. Additionally, we find that prolate ETGs resulting from this formation scenario show a correlation between their stellar line-of-sight velocity and higher order moment h_3, opposite to typical oblate ETGs, as well as a double peak of their stellar velocity dispersion along their minor axis. Finally, we investigate the origin of prolate rotation in polar galaxy merger remnants. Our findings suggest that prolate rotation in massive ETGs might be more common than previously expected, and can help towards a better understanding of their dynamical structure and formation origin.Comment: accepted for publication in A&
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