Behavioural state differentially engages septohippocampal cholinergic and GABAergic neurons in R6/1 Huntington's disease mice

Huntington's disease (HD) is a neurodegenerative condition characterised by progressive motor, psychological and cognitive decline. R6/1 HD transgenic mice model the clinical hippocampal-dependent cognitive deficits observed in patients. Cholinergic and GABAergic septohippocampal projections play important roles in hippocampal-dependent cognition. The current study examined neuronal activity of cholinergic and GABAergic septohippocampal projections in response to arousal elicited during differing behavioural states. The different behavioural states examined were; home cage (controls), acute exploration of a novel enriched environment and either spontaneous wakefulness (dark phase) or spontaneous sleep (light phase). We employed triple-label immunohistochemistry using c-Fos as an indirect marker of neuron activation and parvalbumin and choline acetyltransferase (ChAT) to label GABAergic and cholinergic neurons in the basal forebrain, respectively. The Y-maze was used to assess short-term hippocampal-dependent memory independently during either the dark or light phase and revealed a memory deficit in R6/1 HD mice compared to wild types that was particularly prominent during the dark phase. Three-way ANOVA of basal forebrain cholinergic and GABAergic activity through co-expression of c-Fos revealed overt responses to differing behavioural states. Both genotypes increased cholinergic neuron activity in response to exploring a novel enriched environment and also an increase during the dark phase compared to the light phase. Novel enriched environment exploration caused a larger response of GABAergic neuron activity in R6/1 HD mice, which also failed to increase the activity of GABAergic neurons during the dark phase compared to the light phase as observed for wildtype mice. Basal levels of c-Fos-positive cells were greatly increased in the hippocampal granule cell layer of R6/1 HD mice during both circadian phases. The differential activation of septohippocampal cholinergic and GABAergic neurons in R6/1 HD mice in response to differing behavioural states may be associated with impaired hippocampal-dependent short-term memory.     

Treating disturbed emotional regulation in sexual offenders: The potential applications of mindful self-regulation and controlled breathing techniques

It has been noted that some offenders are characterized by problems in the appropriate regulation of emotional states. Deficits in emotional regulation are particularly pertinent in sexual offenders. Therefore, therapeutic programs should, in part, focus on the development of effective strategies for the control of emotional arousal. In this review, we will provide an outline of how anatomical structures including the amygdala and regions of the prefrontal cortex (PFC) are involved in the appropriate regulation of emotion. It is argued in this paper that the effective control of emotional states may be helped through the adoption of a group of meditational practices, known as mindfulness techniques, which have emerged from Buddhist philosophy. These techniques involve slow, deep breathing and have been shown to affect vagal modulation of the heart and the functioning of specific neural circuits which are critically involved in emotional regulation.     

Text messaging amongst New Zealand drivers: Prevalence and risk perception

Recent work suggests that text messaging impairs simulated and actual driving performance and that this impairment exceeds that of conversing on a cell phone while driving. Additionally, research has shown that text messaging is common in several countries, and despite drivers acknowledging the high risk involved in doing so, drivers continue to engage in this behaviour – regardless of legislation banning it. A nationwide online survey in New Zealand, of 1057 respondents, collected anonymous self-report data regarding the frequency of cell phone use (conversing and text messaging) while driving, beliefs concerning the safety of conversing or text messaging while driving. This article presents part of the results of that study – focusing on text messaging behaviour and risk perception regarding text messaging while driving. Over half of respondents surveyed reported sending or reading between 1 and 5 text messages while driving in a typical week. Despite this, 89% of participants agreed that text messaging while driving in general impairs driving performance. There were no gender differences between the number of text messages read and sent. Age was found to be an important indicator of participant’s willingness to engage in text messaging while driving, with younger drivers more likely to engage in this behaviour. The implications of these findings for future research and countermeasure development are discussed.     

Harm to Future Persons: Non-Identity Problems and Counterpart Solutions

Non-Identity arguments have a pervasive but sometimes counter-intuitive grip on certain key areas in ethics. As a result, there has been limited success in supporting the alternative view that our choices concerning future generations can be considered harmful on any sort of person-affecting principle. However, as the Non-Identity Problem relies overtly on certain metaphysical assumptions, plausible alternatives to these foundations can substantially undermine the Non-Identity argument itself. In this paper, I show how the pervasive force and nature of Non-Identity arguments rely upon a specific adoption of a theory of modality and identity and how adopting an alternative account of modality can be used to reject many conclusions formed through Non-Identity type arguments. By using Lewis’s counterpart-theoretic account to understand ways we might have been, I outline the basis of a modal account of harm that incorporates a person-affecting aspect. This, in turn, has significant implications for ethical decision-making in areas such as reproductive choice and the welfare of future generations.     

Finding MAPs using strongly equivalent high order recurrent symmetric connectionist networks

Belief revision is the problem of finding the most plausible explanation for an observed set of evidences. It has many applications in various scientific domains like natural language understanding, medical diagnosis and computational biology. Bayesian Networks (BN) is an important probabilistic graphical formalism widely used for belief revision tasks. In BN, belief revision can be achieved by finding the maximum a posteriori (MAP) assignment. Finding MAP is an NP-Hard problem. In previous work, we showed how to find the MAP assignment in BN using High Order Recurrent Neural Networks (HORN) through an intermediate representation of Cost-Based Abduction. This method eliminates the need to explicitly construct the energy function in two steps, objective and constraints. This paper builds on that previous work by providing the theoretical foundation and proving that the resultant HORN used to find MAP is strongly equivalent to the original BN it tries to solve.     

Overlapping neural substrates between intentional and incidental down-regulation of negative emotions

Emotion regulation can be achieved in various ways, but few studies have evaluated the extent to which the neurocognitive substrates of these distinct operations overlap. In the study reported here, functional magnetic resonance imaging (fMRI) was used to measure activity in the amygdala and prefrontal cortex of 10 participants who completed two independent tasks of emotion regulation-reappraisal, measuring intentional emotion regulation, and affect labeling, measuring incidental emotion regulation-with the objective of identifying potential overlap in the neural substrates underlying each task. Analyses focused on a priori regions of interest in the amygdala and inferior frontal gyrus (IFG). For both tasks, fMRI showed decreased amygdala activation during emotion regulation compared with emotion conditions. During reappraisal, this decrease in amygdala activation was accompanied by a proportional decrease in emotional intensity ratings; during affect labeling, the decrease in amygdala activation correlated with self-reported aggression. Importantly, across participants, the magnitude of decrease in amygdala activation during reappraisal correlated with the magnitude of decrease during affect labeling, even though the tasks were administered on separate days, and values indexing amygdala activation during each task were extracted independently of one another. In addition, IFG-amygdala connectivity, assessed via psychophysiological interaction analysis, overlapped between tasks in two regions within the right IFG. The results suggest that the two tasks recruit overlapping regions of prefrontal cortex, resulting in similar reductions in amygdala activation, regardless of the strategy employed. Intentional and incidental forms of emotion regulation, despite their phenomenological differences, may therefore converge on a common neurocognitive pathway.     

Elevated responding to safe conditions as a specific risk factor for anxiety versus depressive disorders: evidence from a longitudinal investigation

The current study evaluated the degree to which startle reflexes (SRs) in safe conditions versus danger conditions were predictive of the onset of anxiety disorders. Specificity of these effects to anxiety disorders was evaluated in comparison to unipolar depressive disorders and with consideration of level of neuroticism. A startle paradigm was administered at baseline to 132 nondisordered adolescents as part of a longitudinal study examining risk factors for emotional disorders. Participants underwent a repetition of eight safe-danger sequences and were told that delivery of an aversive stimulus leading to a muscle contraction of the arm would occur only in the late part of danger conditions. One aversive stimulus occurred midway in the safe-danger sequences. Participants were assessed for the onset of anxiety and unipolar depressive disorders annually over the next 3 to 4 years. Larger SR magnitude during safe conditions following delivery of the aversive stimulus predicted the subsequent first onset of anxiety disorders. Moreover, prediction of the onset of anxiety disorders remained significant above and beyond the effects of comorbid unipolar depression, neuroticism, and subjective ratings of intensity of the aversive stimulus. In sum, elevated responding to safe conditions following an aversive stimulus appears to be a specific, prospective risk factor for the first onset of anxiety disorders.     

Mind the gap: assessing impairment among children affected by proposed revisions to the diagnostic criteria for oppositional defiant disorder

The Diagnostic and Statistical Manual for Mental Disorders, Fifth Edition (DSM-5) workgroup for disruptive behavior disorders is considering adopting a frequency threshold for symptoms of oppositional defiant disorder (ODD). In the present study, the impact of substituting the term "often" with a specific age-based frequency on impairment and prognosis among preschool children was tested in a longitudinal design. Mutually exclusive groups were created to identify children who met criteria for ODD based on a symptom threshold of "often," as in Diagnostic and Statistical Manual for Mental Disorders, Fourth Edition (DSM-4), and those that met criteria for ODD based on a threshold of "1-2 times per day," which approximated the proposal for DSM-5. Comparisons of these groups to each other and to nondiagnosed peers determined the impact of changing the symptom threshold on impairment and prognosis. Close to one-third of children who met DSM-4 criteria for ODD did not meet criteria under the alternative diagnosis; African American children were overrepresented in this group. Preschoolers who met DSM-4, but not the alternative criteria, had higher rates of ODD, conduct disorder (CD), and were more impaired than their nondiagnosed peers at baseline and follow-up. Preschoolers meeting DSM-4 criteria were less impaired than children meeting the alternative ODD criteria at baseline according to parent, but not according to teacher report. No differences could be detected between those meeting DSM-4 and those meeting the alternative criteria in rate of ODD, CD, or impairment at follow-up. Among clinically referred preschool children, changing the symptom threshold for ODD could result in a sizable group of children who would no longer meet diagnostic criteria, despite demonstrating significant morbidity concurrently and prospectively.     

How do alternative ways of responding influence 3- and 4-year-olds’ performance on tests of executive function and theory of mind?

A total of 69 preschool children were tested on measures of false belief understanding (the Unexpected Transfer task), inhibitory control (the Grass/Snow task), and strategic reasoning (the Windows task). For each task, children indicated their response either by pointing with their index finger or by using a nonstandard response mode (pointing with a rotating arrow). The means of responding had no effect on children's performance on the Grass/Snow task or on the Unexpected Transfer task, although children performed better on the Unexpected Transfer task when the key object in the story was removed. In contrast, performance on the Windows task was significantly better when children pointed with the rotating arrow. A follow-up experiment with 79 preschoolers found that this improved performance on the Windows task was sustained even after the nonstandard response mode was removed and children again pointed with their finger. These findings together suggest that nonstandard response modes do not help children to inhibit prepotent pointing responses but may help them to formulate response strategies on reasoning tasks by discouraging unreflective impulsive responding.     

In perfect harmony: synchronizing the self to activated social categories

The self-concept is one of the main organizing constructs in the behavioral sciences because it influences how people interpret their environment, the choices they make, whether and how they initiate action, and the pursuit of specific goals. Because belonging to social groups and feeling interconnected is critical to human survival, the authors propose that people spontaneously change their working self-concept so that they are more similar to salient social categories. Specifically, 4 studies investigated whether activating a variety of social categories (i.e., jocks, hippies, the overweight, Blacks, and Asians) increased associations between the self and the target category. Whereas Studies 1 and 2 focused on associations between stereotypic traits and the self, Studies 3 and 4 examined self-perceptions and self-categorizations, respectively. The results provide consistent evidence that following social category priming, people synchronized the self to the activated category. Furthermore, the findings indicate that factors that influence category activation, such as social goals, and factors that induce a focus on the interconnectedness of the self, such as an interdependent vs. independent self-construal, can impact this process. The implications of changes to the working self-concept for intergroup relations are discussed.