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1.
PLoS One ; 15(2): e0228416, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32012193

RESUMO

Intrusive memories are a core symptom of Post-Traumatic Stress Disorder (PTSD). A growing body of analogue studies using trauma films suggest that carrying out specific demanding tasks (e.g., playing the video game Tetris, pattern tapping) after the analogue trauma can reduce intrusive memories. To examine the mechanism behind this effect, we tested whether mere engagement with attention-grabbing and interesting visual stimuli disrupts intrusive memories, and whether this depends on working memory resources and/or the concurrent activation of trauma film memories. In a total sample of 234 healthy participants, we compared no-task control conditions to a perceptual rating task with visually arresting video clips (i.e., non-emotional, complex, moving displays), to a less arresting task with non-moving, blurred pictures (Study 1), and to more demanding imagery tasks with and without repetitive reminders of the trauma film (Study 2). Generally, we found moderate to strong evidence that none of the conditions lead to differences in intrusion frequency. Moreover, our data suggest that intrusive memories were neither related to individual differences in working memory capacity (i.e., operation span performance; Study 1), nor to the degree of engagement with a visuospatial task (i.e., one-week recognition performance; Study 2). Taken together, our findings suggest that the boundary conditions for successful interference with traumatic intrusions may be more complex and subtle than assumed. Future studies may want to test the role of prediction errors during (re-)consolidation, deliberate efforts to suppress thoughts, or the compatibility of the task demands with the individual's skills.


Assuntos
Emoções/fisiologia , Individualidade , Rememoração Mental/fisiologia , Estimulação Luminosa , Reconhecimento Psicológico/fisiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Estresse Psicológico , Adolescente , Adulto , Atenção , Feminino , Humanos , Acontecimentos que Mudam a Vida , Masculino , Processamento Espacial , Jogos de Vídeo , Adulto Jovem
2.
Neurobiol Learn Mem ; 166: 107093, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31536787

RESUMO

BACKGROUND: Posttraumatic stress disorder (PTSD) is characterized by distressing trauma-related memories. According to the dual representation theory, intrusive memories arise from strengthened egocentric encoding and a poor contextual encoding, with spatial context requiring allocentric processing. Contextualization of mental imagery is proposed to be formed hierarchically through the ventral visual stream (VVS) to the hippocampal formation. Here, we tested this notion by investigating whether neuronal aberrations in structures of the VVS or in the hippocampus, as well as allocentric memory performance are associated with intrusive memory severity. METHODS: The sample comprised 33 women with PTSD due to childhood trauma. Allocentric memory performance was measured with the virtual Town Square Task and T1-weighted images acquired on a 3T Siemens Scanner. Intrusive memories were evoked by presenting an audio script describing parts of their trauma (script-driven imagery). RESULTS: Using hierarchical linear regression analysis, we found a significant association between lower intrusive memory severity and higher allocentric spatial memory, controlling for age, working memory, and general visuospatial ability. No significant association was found between cortical thickness of VVS structures, hippocampal volume and intrusive memory severity. Post hoc exploratory analyses revealed a negative correlation between years since index trauma and left hippocampal volume. LIMITATIONS: Our results are based on correlational analyses, causality cannot be inferred. CONCLUSION: This study supports the dual representation theory, which emphasizes the role of allocentric spatial memory for the contextualization of mental imagery in PTSD. Clinical implications are discussed.


Assuntos
Adultos Sobreviventes de Eventos Adversos na Infância/psicologia , Memória de Curto Prazo/fisiologia , Memória Espacial/fisiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Adulto , Feminino , Hipocampo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Testes Neuropsicológicos , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Adulto Jovem
3.
PLoS One ; 14(1): e0210283, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30673735

RESUMO

Compassion is a complex cognitive, emotional and behavioural process that has important real-world consequences for the self and others. Considering this, it is important to understand how compassion is communicated. The current research investigated the expression and perception of compassion via the face. We generated exemplar images of two compassionate facial expressions induced from two mental imagery tasks with different compassionate motivations (Study 1). Our kind- and empathic compassion faces were perceived differently and the empathic-compassion expression was perceived as best depicting the general definition of compassion (Study 2). Our two composite faces differed in their perceived happiness, kindness, sadness, fear and concern, which speak to their underling motivation and emotional resonance. Finally, both faces were accurately discriminated when presented along a compassion continuum (Study 3). Our results demonstrate two perceptually and functionally distinct facial expressions of compassion, with potentially different consequences for the suffering of others.


Assuntos
Empatia , Expressão Facial , Adolescente , Adulto , Gráficos por Computador , Simulação por Computador , Emoções , Feminino , Humanos , Masculino , Modelos Psicológicos , Motivação , Comportamento Social , Adulto Jovem
4.
Muscles Ligaments Tendons J ; 7(1): 78-87, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28717615

RESUMO

BACKGROUND: The intra-tendinous tear is a new pathology that is defined as a discontinuity of fibres situated entirely within the tendon. Prolotherapy involves injecting an irritant, such as hyperosmolar dextrose, to stimulate a tissue healing response and ultimately reduce pain. METHODS: 43 consecutive patients diagnosed with an intra-tendinous tear were included (27 males: 16 females, mean (SD) age 41 (11.3). Patients were injected with 0.4ml-1.5ml (mean 0.8ml) of 50% dextrose and 0.5% marcaine mixed in a 1:1 ratio. A 4-6 week period of walking boot immobilisation was followed by progressive rehabilitation (6-8 weeks). Outcomes were assessed with a VISA-A questionnaire at baseline, 3 months and a mean 12.6 (7.0) months post-treatment. Ultrasound scans were conducted before treatment and 5.2 (2.3) weeks later to assess sonographic changes. RESULTS: 30 patients (70%) responded with VISA-A scores increasing by 31 (30.5) points after 3 months (f=0.62, p<0.05) and by 40 (29.3) points after 12.60 (7.0) months (f=0.87, p<0.05). After 5.2 (2.3) weeks, echogenicity was significantly reduced (p<0.05) and 27% of tears were no longer detectable. No significant differences were observed in remaining tears with respect to tear size, tendon thickness or neovascularisation. CONCLUSION: Treatment resulted in clinically significant improvements and controlled trials are warranted. LEVEL OF EVIDENCE: IV.

5.
New Phytol ; 213(2): 778-790, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27787905

RESUMO

Viable pollen is essential for plant reproduction and crop yield. Its production requires coordinated expression at specific stages during anther development, involving early meiosis-associated events and late pollen wall formation. The ABORTED MICROSPORES (AMS) transcription factor is a master regulator of sporopollenin biosynthesis, secretion and pollen wall formation in Arabidopsis. Here we show that it has complex regulation and additional essential roles earlier in pollen formation. An inducible-AMS reporter was created for functional rescue, protein expression pattern analysis, and to distinguish between direct and indirect targets. Mathematical modelling was used to create regulatory networks based on wild-type RNA and protein expression. Dual activity of AMS was defined by biphasic protein expression in anther tapetal cells, with an initial peak around pollen meiosis and then later during pollen wall development. Direct AMS-regulated targets exhibit temporal regulation, indicating that additional factors are associated with their regulation. We demonstrate that AMS biphasic expression is essential for pollen development, and defines distinct functional activities during early and late pollen development. Mathematical modelling suggests that AMS may competitively form a protein complex with other tapetum-expressed transcription factors, and that biphasic regulation is due to repression of upstream regulators and promotion of AMS protein degradation.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Pólen/crescimento & desenvolvimento , Pólen/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Dexametasona/farmacologia , Fertilidade/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Modelos Biológicos , Mutação/genética , Pólen/efeitos dos fármacos , Pólen/genética , Ligação Proteica/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Proteínas Recombinantes de Fusão/metabolismo
6.
Plant Physiol ; 167(4): 1717-30, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25667314

RESUMO

Floral formation, in particular anther and pollen development, is a complex biological process with critical importance for seed set and for targeted plant breeding. Many key transcription factors regulating this process have been identified; however, their direct role remains largely unknown. Using publicly available gene expression data from Arabidopsis (Arabidopsis thaliana), focusing on those studies that analyze stamen-, pollen-, or flower-specific expression, we generated a network model of the global transcriptional interactions (FlowerNet). FlowerNet highlights clusters of genes that are transcriptionally coregulated and therefore likely to have interacting roles. Focusing on four clusters, and using a number of data sets not included in the generation of FlowerNet, we show that there is a close correlation in how the genes are expressed across a variety of conditions, including male-sterile mutants. This highlights the important role that FlowerNet can play in identifying new players in anther and pollen development. However, due to the use of general floral expression data in FlowerNet, it also has broad application in the characterization of genes associated with all aspects of floral development and reproduction. To aid the dissection of genes of interest, we have made FlowerNet available as a community resource (http://www.cpib.ac.uk/anther). For this resource, we also have generated plots showing anther/flower expression from a variety of experiments: These are normalized together where possible to allow further dissection of the resource.


Assuntos
Arabidopsis/genética , Bases de Dados Genéticas , Flores/genética , Regulação da Expressão Gênica de Plantas/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Análise por Conglomerados , Flores/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Análise de Sequência com Séries de Oligonucleotídeos , Pólen/genética , Pólen/crescimento & desenvolvimento , Reprodução , Fatores de Transcrição/genética
7.
Neurobiol Learn Mem ; 119: 69-76, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25636201

RESUMO

A neurobiological dual representation model of PTSD proposes that reduced hippocampus-dependent contextual processing contributes to intrusive imagery due to a loss of control over hippocampus-independent sensory and affective representations. We investigated whether PTSD sufferers show impaired allocentric spatial processing indicative of reduced hippocampal functioning. Trauma-exposed individuals with (N=29) and without (N=30) a diagnosis of PTSD completed two tests of spatial processing: a topographical recognition task comprising perceptual and memory components, and a test of memory for objects' locations within a virtual environment in which the test is from either the same viewpoint as presentation (solvable with egocentric memory) or a different viewpoint (requiring allocentric memory). Participants in the PTSD group performed significantly worse on allocentric spatial processing than trauma-exposed controls. Groups performed comparably on egocentric memory and non-spatial memory for lists of objects. Exposure to repeated incident trauma was also associated with significantly worse spatial processing in the PTSD group. Results show a selective impairment in allocentric spatial processing, implicating weak hippocampal functioning, as predicted by a neurobiological dual representation model of PTSD. These findings have important clinical implications for cognitive therapy.


Assuntos
Percepção Espacial , Memória Espacial , Transtornos de Estresse Pós-Traumáticos/psicologia , Adolescente , Adulto , Idoso , Feminino , Hipocampo/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Psicológico , Adulto Jovem
8.
Front Hum Neurosci ; 8: 709, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25278860

RESUMO

The traditional view of the medial temporal lobe (MTL) focuses on its role in episodic memory. However, some of the underlying functions of the MTL can be ascertained from its wider role in supporting spatial cognition in concert with parietal and prefrontal regions. The MTL is strongly implicated in the formation of enduring allocentric representations (e.g., O'Keefe, 1976; King et al., 2002; Ekstrom et al., 2003). According to our BBB model (Byrne et al., 2007), these representations must interact with head-centered and body-centered representations in posterior parietal cortex via a transformation circuit involving retrosplenial areas. Egocentric sensory representations in parietal areas can then cue the recall of allocentric spatial representations in long-term memory and, conversely, the products of retrieval in MTL can generate mental imagery within a parietal "window." Such imagery is necessarily egocentric and forms part of visuospatial working memory, in which it can be manipulated for the purpose of planning/imagining the future. Recent fMRI evidence (Lambrey et al., 2012; Zhang et al., 2012) supports the BBB model. To further test the model, we had participants learn the locations of objects in a virtual scene and tested their spatial memory under conditions that impose varying demands on the transformation circuit. We analyzed how brain activity correlated with accuracy in judging the direction of an object (1) from visuospatial working memory (we assume transient working memory due to the order of tasks and the absence of change in viewpoint, but long-term memory retrieval is also possible), (2) after a rotation of viewpoint, or (3) after a rotation and translation of viewpoint (judgment of relative direction). We found performance-related activity in both tasks requiring viewpoint rotation (ROT and JRD, i.e., conditions 2 and 3) in the core medial temporal to medial parietal circuit identified by the BBB model. These results are consistent with the predictions of the BBB model, and shed further light on the neural mechanisms underlying spatial memory, mental imagery and viewpoint transformations.

9.
Healthc Manage Forum ; 27(1 Suppl): S58-78, 2014.
Artigo em Inglês, Francês | MEDLINE | ID: mdl-25046971

RESUMO

This article examines the way that non-clinical support services are provided in healthcare settings through outsourcing partnerships. The integrated support services model and benefits to patient experience and safety as well as organizational efficiency and effectiveness are explored through an examination of services at a busy urban community hospital.


Assuntos
Prestação Integrada de Cuidados de Saúde/organização & administração , Hospitais Gerais , Serviços Terceirizados , Qualidade de Vida , Eficiência Organizacional , Humanos , Modelos Organizacionais , Ontário , Estudos de Casos Organizacionais
10.
Cogn Emot ; 27(1): 150-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22712454

RESUMO

This study tested the hypothesis that the presence and characteristics of naturally occurring involuntary imagery would be related to poorer context-dependent spatial memory and higher levels of proneness to psychotic experiences. Poorer contextual memory was also predicted to be associated with a greater sense of "nowness". Participants completed a virtual environment task that assessed contextual memory through responses that required allocentric and egocentric processing of virtual stimuli. Two questionnaires assessing predisposition to psychotic experiences were employed. Finally, participants completed an interview that required details of recent, naturally occurring involuntary images. Reports of involuntary imagery were associated with greater proneness to psychotic experiences but not with memory. In those participants who reported imagery, however, poorer memory performance was associated with more vivid and detailed intrusive imagery. Poorer contextual memory was specifically associated with a greater sense of "nowness". Possible links between contextual memory and proneness to psychosis are discussed.


Assuntos
Imaginação , Memória , Transtornos Psicóticos/psicologia , Adolescente , Adulto , Feminino , Humanos , Londres , Masculino , Pessoa de Meia-Idade , Risco , Inquéritos e Questionários , Percepção do Tempo , Volição
11.
Bull NYU Hosp Jt Dis ; 69(2): 173-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22035397

RESUMO

The pivot shift test is a cornerstone in the clinical diagnosis of anterior cruciate ligament (ACL) deficiency. It can be difficult to perform in overweight patients or in those with long or bulky legs. We present an alternative method to perform the pivot shift test that recalls the judo technique of figure-of-four knee lock and eases the examination of the patient with anterior cruciate ligament deficiency. This modality of execution also makes the surgeon able to perform varus-valgus tests with small changes in hand positions. The surgeon, embracing with one arm the tibia of the affected limb, grasps with this hand the wrist of his free arm opposite to the affected limb. Then the surgeon hooks onto the posterior surface of the leg with his free hand. In this way, the surgeon can exert a moment on the limb of the patient, and can apply combined internal rotation, flexion, and valgus stress to perform the pivot shift test or simply varus or valgus force to perform the varus-valgus tests.


Assuntos
Ligamento Cruzado Anterior/fisiopatologia , Instabilidade Articular/diagnóstico , Exame Físico , Lesões do Ligamento Cruzado Anterior , Fenômenos Biomecânicos , Humanos , Instabilidade Articular/fisiopatologia , Artes Marciais , Posicionamento do Paciente , Valor Preditivo dos Testes
12.
J Neurosci ; 30(35): 11688-95, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20810889

RESUMO

When we visualize scenes, either from our own past or invented, we impose a viewpoint for our "mind's eye" and we experience the resulting image as spatially coherent from that viewpoint. The hippocampus has been implicated in this process, but its precise contribution is unknown. We tested a specific hypothesis based on the spatial firing properties of neurons in the hippocampal formation of rats, that this region supports the construction of spatially coherent mental images by representing the locations of the environmental boundaries surrounding our viewpoint. Using functional magnetic resonance imaging, we show that hippocampal activation increases parametrically with the number of enclosing boundaries in the imagined scene. In contrast, hippocampal activity is not modulated by a nonspatial manipulation of scene complexity nor to increasing difficulty of imagining the scenes in general. Our findings identify a specific computational role for the hippocampus in mental imagery and episodic recollection.


Assuntos
Hipocampo/fisiologia , Imaginação/fisiologia , Rememoração Mental/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa/métodos , Adulto , Animais , Humanos , Masculino , Memória/fisiologia , Desempenho Psicomotor/fisiologia , Ratos , Percepção Espacial/fisiologia , Adulto Jovem
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