•Contextual fear memories undergo consolidation in both amygdala and hippocampus.•The hippocampus maintains contextual fear memories.•The amygdala may also maintain contextual fear memories.
Context ...is an ever-present combination of discrete environmental elements capable of influencing many psychological processes. When context is associated with an aversive stimulus, a permanent contextual fear memory is formed. Context is hypothesized to greatly influence the treatability of various fear-based pathologies, in particular, post-traumatic stress disorder (PTSD). In order to understand how contextual fear memories are encoded and impact underlying fear pathology, delineation of the underlying neural circuitry of contextual fear memory consolidation and maintenance is essential. Past understandings of contextual fear suggest that the hippocampus only creates a unitary, or single, representation of context. This representation is sent to the amygdala, which creates the associative contextual fear memory. In contrast, here we review new evidence from the literature showing contextual fear memories to be consolidated and maintained by both amygdala and hippocampus. Based on this evidence, we revise the current model of contextual fear memory consolidation, highlighting a larger role for hippocampus. This new model may better explain the role of the hippocampus in PTSD.
Teacher Attitudes on Creativity JOHNSON, Luke
International journal of educational spectrum (Online),
02/2023, Letnik:
5, Številka:
1
Journal Article
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Teacher attitudes affect student achievement, satisfaction, and self-worth. While accommodations and support networks have long been established for students with exceptional abilities (e.g. ...gifted-talented students and student athletes), creative students are largely ignored in curriculum and school support. Generally, teachers support creativity in principle, but creative students exhibit characteristics and behaviors largely deemed undesirable, although creative people and students can further studies regarding Csikszentmihalyi’s concepts of flow. The basic question of concern is this: What are teacher attitudes towards creativity and creative students? This literature review attempts to understand teacher attitudes, feelings, perspectives, or emotions regarding creativity, with a call for further research and study.
Parkinson’s disease (PD) is a progressive neurodegenerative movement disorder affecting over 10 million people worldwide. In the 1930s and 1940s there was little understanding regarding what caused ...PD or how to treat it. In a desperate attempt to improve patients’ lives different regions of the neuraxis were ablated. Morbidity and mortality were common, but some patients’ motor signs improved with lesions involving the basal ganglia or thalamus. With the discovery of L-dopa the advent of medical therapy began and surgical approaches became less frequent. It soon became apparent, however, that medical therapy was associated with side effects in the form of drug-induced dyskinesia and motor fluctuations and surgical therapies reemerged. Fortunately, during this time studies in monkeys had begun to lay the groundwork to understand the functional organization of the basal ganglia, and with the discovery of the neurotoxin MPTP a monkey model of PD had been developed. Using this model scientists were characterizing the physiological changes that occurred in the basal ganglia in PD and models of basal ganglia function and dysfunction were proposed. This work provided the rationale for the return of pallidotomy, and subsequently deep brain stimulation procedures. In this paper we describe the evolution of these monkey studies, how they provided a greater understanding of the pathophysiology underlying the development of PD and provided the rationale for surgical procedures, the search to understand mechanisms of DBS, and how these studies have been instrumental in understanding PD and advancing the development of surgical therapies for its treatment.
Hydrogen evolution reaction (HER) via electrocatalysis is one method of enabling sustainable production of molecular hydrogen as a clean and promising energy carrier. Previous theoretical and ...experimental results have shown that some two-dimensional (2D) transition metal carbides (MXenes) can be effective electrocatalysts for the HER, based on the assumption that they are functionalized entirely with oxygen or hydroxyl groups on the basal plane. However, it is known that MXenes can contain other basal plane functionalities, e.g., fluorine, due to the synthesis process, yet the influence of fluorine termination on their HER activity remains unexplored. In this paper, we investigate the role and effect of basal plane functionalization (T x ) on the HER activity of 5 different MXenes using a combination of experimental and theoretical approaches. We first studied Ti3C2T x produced by different fluorine-containing etchants and found that those with higher fluorine coverage on the basal plane exhibited lower HER activity. We then controllably prepared Mo2CT x with very low basal plane fluorine coverage, achieving a geometric current density of −10 mA cm–2 at 189 mV overpotential in acid. More importantly, our results indicate that the oxygen groups on the basal planes of Mo2CT x are catalytically active toward the HER, unlike in the case of widely studied 2H-phase transition metal dichalcogenides such as MoS2, in which only the edge sites are active. These results pave the way for the rational design of 2D materials for either the HER, when minimal overpotential is desired, or for energy storage, when maximum voltage window is needed.
We propose a methodology for predicting the printability of an alloy, subject to laser powder bed fusion additive manufacturing. Regions in the process space associated with keyhole formation, ...balling, and lack of fusion are assumed to be strong functions of the geometry of the melt pool, which in turn is calculated for various combinations of laser power and scan speed via a Finite Element thermal model that incorporates a novel vaporization-based transition from surface to volumetric heating upon keyhole formation. Process maps established from the Finite Element simulations agree with experiments for a Ni-5wt.%Nb alloy and an equiatomic CoCrFeMnNi High Entropy Alloy and suggest a strong effect of chemistry on alloy printability. The printability maps resulting from the use of the simpler Eagar-Tsai model, on the other hand, are found to be in disagreement with experiments due to the oversimplification of this approach. Uncertainties in the printability maps were quantified via Monte Carlo sampling of a multivariate Gaussian Processes surrogate model trained on simulation outputs. The printability maps generated with the proposed method can be used in the selection—and potentially the design—of alloys best suited for Additive Manufacturing.
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Deep brain stimulation (DBS) of the subthalamic nucleus (STN) and globus pallidus internus (GPi) is an effective treatment for parkinsonian motor signs. Though its therapeutic mechanisms remain ...unclear, it has been suggested that antidromic activation of the primary motor cortex (M1) plays a significant role in mediating its therapeutic effects. This study tested the hypothesis that antidromic activation of M1 is a prominent feature underlying the therapeutic effect of STN and GPi DBS. Single-unit activity in M1 was recorded using high-density microelectrode arrays in two parkinsonian nonhuman primates each implanted with DBS leads targeting the STN and GPi. Stimulation in each DBS target had similar therapeutic effects, however, antidromic activation of M1 was only observed during STN DBS. Although both animals undergoing STN DBS had similar beneficial effects, the proportion of antidromic-classified cells in each differed, 30 versus 6%. Over 4 h of continuous STN DBS, antidromic activation became less robust, whereas therapeutic benefits were maintained. Although antidromic activation waned over time, synchronization of spontaneous spiking in M1 was significantly reduced throughout the 4 h. Although we cannot discount the potential therapeutic role of antidromic M1 activation at least in the acute phase of STN DBS, the difference in observed antidromic activation between animals, and target sites, raise questions about its hypothesized role as the primary mechanism underlying the therapeutic effect of DBS. These results lend further support that reductions in synchronization at the level of M1 are an important factor in the therapeutic effects of DBS.
Recently there has been great interest and debate regarding the potential role of motor cortical activation in the therapeutic mechanisms of deep brain stimulation (DBS) for Parkinson's disease. In this study we used chronically implanted high density microelectrode arrays in primary motor cortex (M1) to record neuronal population responses in parkinsonian nonhuman primates during subthalamic nucleus (STN) DBS and globus pallidus internus (GPi) DBS. Our results suggest a contribution of antidromic activation of M1 during STN DBS in disrupting synchronization in cortical neuronal populations; however, diminishing antidromic activity over time, and differences in observed antidromic activation between animals and target sites with antidromic activation not observed during GPi DBS, raise questions about its role as the primary mechanism underlying the therapeutic effect of DBS.
Post-traumatic stress disorder (PTSD), characterized by abnormally persistent and distressing memories, is a chronic debilitating condition in need of new treatment options. Current treatment ...guidelines recommend psychotherapy as first line management with only two drugs, sertraline and paroxetine, approved by U.S. Food and Drug Administration (FDA) for treatment of PTSD. These drugs have limited efficacy as they only reduce symptoms related to depression and anxiety without producing permanent remission. PTSD remains a significant public health problem with high morbidity and mortality requiring major advances in therapeutics. Early evidence has emerged for the beneficial effects of psychedelics particularly in combination with psychotherapy for management of PTSD, including psilocybin, MDMA, LSD, cannabinoids, ayahuasca and ketamine. MDMA and psilocybin reduce barrier to therapy by increasing trust between therapist and patient, thus allowing for modification of trauma related memories. Furthermore, research into the memory reconsolidation mechanisms has allowed for identification of various pharmacological targets to disrupt abnormally persistent memories. A number of pre-clinical and clinical studies have investigated novel and re-purposed pharmacological agents to disrupt fear memory in PTSD. Novel therapeutic approaches like neuropeptide Y, oxytocin, cannabinoids and neuroactive steroids have also shown potential for PTSD treatment. Here, we focus on the role of fear memory in the pathophysiology of PTSD and propose that many of these new therapeutic strategies produce benefits through the effect on fear memory. Evaluation of recent research findings suggests that while a number of drugs have shown promising results in preclinical studies and pilot clinical trials, the evidence from large scale clinical trials would be needed for these drugs to be incorporated in clinical practice.
ObjectiveTo examine the extent, nature and quality of literature on the impact of the COVID-19 pandemic on the mental health of imprisoned people and prison staff.DesignScoping review.Data ...sourcesPubMed, Embase, CINAHL, Global Health, Cochrane, PsycINFO, PsychExtra, Web of Science and Scopus were searched for any paper from 2019 onwards that focused on the mental health impact of COVID-19 on imprisoned people and prison staff. A grey literature search focused on international and government sources and professional bodies representing healthcare, public health and prison staff was also performed. We also performed hand searching of the reference lists of included studies.Eligibility criteria for selection of studiesAll papers, regardless of study design, were included if they examined the mental health of imprisoned people or prison staff specifically during the COVID-19 pandemic. Imprisoned people could be of any age and from any countries. All languages were included. Two independent reviewers quality assessed appropriate papers.ResultsOf 647 articles found, 83 were eligible for inclusion, the majority (58%) of which were opinion pieces. The articles focused on the challenges to prisoner mental health. Fear of COVID-19, the impact of isolation, discontinuation of prison visits and reduced mental health services were all likely to have an adverse effect on the mental well-being of imprisoned people. The limited research and poor quality of articles included mean that the findings are not conclusive. However, they suggest a significant adverse impact on the mental health and well-being of those who live and work in prisons.ConclusionsIt is key to address the mental health impacts of the pandemic on people who live and work in prisons. These findings are discussed in terms of implications for getting the balance between infection control imperatives and the fundamental human rights of prison populations.
We demonstrate a method to achieve local control of 3-dimensional thermal history in a metallic alloy, which resulted in designed spatial variations in its functional response. A nickel-titanium ...shape memory alloy part was created with multiple shape-recovery stages activated at different temperatures using the selective laser melting technique. The multi-stage transformation originates from differences in thermal history, and thus the precipitate structure, at various locations created from controlled variations in the hatch distance within the same part. This is a first example of precision location-dependent control of thermal history in alloys beyond the surface, and utilizes additive manufacturing techniques as a tool to create materials with novel functional response that is difficult to achieve through conventional methods.
Two studies investigated the possible divergence between grandiose and vulnerable narcissism with regard to guilt- and shame-related traits and reactivity of these emotions. Participants in Study 1 (
...N
= 688;
M
age = 19.5; 64.4% female) completed self-report measures regarding narcissism dimensions, as well as general and self-conscious emotion propensities and aversions. Participants in Study 2 (
N
= 142;
M
age = 18.9; 69.2% female) provided state emotion ratings before and after an imaginal social rejection task, in addition to completing measures of narcissism dimensions. Across both studies, guilt was more relevant to grandiose narcissism. In Study 1, guilt-proneness was negatively associated with grandiose narcissism, but only when guilt aversion was low. Relatedly, Study 2 demonstrated that greater grandiose narcissism was associated with lower guilt reactivity following an interpersonal stressor. Comparatively, in Study 1, shame-related traits were positively associated with vulnerable narcissism, though guilt-proneness was negatively associated with vulnerable narcissism. Additionally, Study 2 indicated that greater vulnerable narcissism was associated with heightened reactivity of both shame and guilt. The present study thus builds on the limited research evidence on self-conscious emotions and narcissism, highlighting the sometimes opposing roles of guilt and shame in relation to these different but related personality dimensions.
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