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1.
Gut ; 69(2): 283-294, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31471351

RESUMO

OBJECTIVE: Cerebral amyloidosis and severe tauopathy in the brain are key pathological features of Alzheimer's disease (AD). Despite a strong influence of the intestinal microbiota on AD, the causal relationship between the gut microbiota and AD pathophysiology is still elusive. DESIGN: Using a recently developed AD-like pathology with amyloid and neurofibrillary tangles (ADLPAPT) transgenic mouse model of AD, which shows amyloid plaques, neurofibrillary tangles and reactive gliosis in their brains along with memory deficits, we examined the impact of the gut microbiota on AD pathogenesis. RESULTS: Composition of the gut microbiota in ADLPAPT mice differed from that of healthy wild-type (WT) mice. Besides, ADLPAPT mice showed a loss of epithelial barrier integrity and chronic intestinal and systemic inflammation. Both frequent transfer and transplantation of the faecal microbiota from WT mice into ADLPAPT mice ameliorated the formation of amyloid ß plaques and neurofibrillary tangles, glial reactivity and cognitive impairment. Additionally, the faecal microbiota transfer reversed abnormalities in the colonic expression of genes related to intestinal macrophage activity and the circulating blood inflammatory monocytes in the ADLPAPT recipient mice. CONCLUSION: These results indicate that microbiota-mediated intestinal and systemic immune aberrations contribute to the pathogenesis of AD in ADLPAPT mice, providing new insights into the relationship between the gut (colonic gene expression, gut permeability), blood (blood immune cell population) and brain (pathology) axis and AD (memory deficits). Thus, restoring gut microbial homeostasis may have beneficial effects on AD treatment.


Assuntos
Doença de Alzheimer/microbiologia , Doença de Alzheimer/terapia , Transplante de Microbiota Fecal , Microbioma Gastrointestinal/fisiologia , Doença de Alzheimer/metabolismo , Animais , Comportamento Animal , Doença Crônica , Modelos Animais de Doenças , Humanos , Inflamação/microbiologia , Intestinos/microbiologia , Memória de Curto Prazo , Camundongos Transgênicos , Permeabilidade , Placa Amiloide/microbiologia , Placa Amiloide/patologia , Aprendizagem Espacial , Proteínas tau/análise
2.
J Sports Sci ; 38(3): 320-329, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31782684

RESUMO

Elite athletes not only run faster, hit harder, and jump higher, but also see and react better. However, the specific visual-motor skills that differentiate high-achieving athletes are still not well understood. In this paper we examine 2317 athletes (1871 male) tested on the Nike SPARQ Sensory Station, a digital test battery measuring visual, perceptual and motor skills relevant for sports performance. We develop a multivariate Gaussian transformation model to robustly estimate visual-motor differences by level, gender, and sport type. Results demonstrate that visual-motor performance is superior for athletes at higher levels, with males faster at near-far eye movements and females faster at eye-hand reaction times. Interestingly, athletes who play interceptive sports such as baseball and tennis exhibit better measures of visual clarity, contrast sensitivity and simple reaction time, while athletes from strategic sports like soccer and basketball have higher measures of spatial working memory. These findings provide quantitative evidence of domain-specific visual expertise in athletes.


Assuntos
Desempenho Atlético/fisiologia , Desempenho Atlético/psicologia , Destreza Motora/fisiologia , Percepção Visual/fisiologia , Teorema de Bayes , Feminino , Humanos , Masculino , Memória de Curto Prazo , Tempo de Reação , Análise de Regressão , Fatores Sexuais , Análise e Desempenho de Tarefas
3.
Arch Dis Child Fetal Neonatal Ed ; 105(1): 8-13, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31036702

RESUMO

OBJECTIVE: Since therapeutic hypothermia became standard care for neonatal hypoxic-ischaemic encephalopathy (HIE), even fewer infants die or have disability at 18-month assessment than in the clinical trials. However, longer term follow-up of apparently unimpaired children is lacking. We investigated the cognitive, motor and behavioural performances of survivors without cerebral palsy (CP) cooled for HIE, in comparison with matched non-HIE control children at 6-8 years. DESIGN: Case-control study. PARTICIPANTS: 29 case children without CP, cooled in 2008-2010 and 20 age-matched, sex-matched and social class-matched term-born controls. MEASURES: Wechsler Intelligence Scales for Children, Fourth UK Edition, Movement Assessment Battery for Children, Second Edition (MABC-2) and Strengths and Difficulties Questionnaire. RESULTS: Cases compared with controls had significantly lower mean (SD) full-scale IQ (91 [10.37]vs105[13.41]; mean difference (MD): -13.62, 95% CI -20.53 to -6.71) and total MABC-2 scores (7.9 [3.26]vs10.2[2.86]; MD: -2.12, 95% CI -3.93 to -0.3). Mean differences were significant between cases and controls for verbal comprehension (-8.8, 95% CI -14.25 to -3.34), perceptual reasoning (-13.9, 95% CI-20.78 to -7.09), working memory (-8.2, 95% CI-16.29 to -0.17), processing speed (-11.6, 95% CI-20.69 to -2.47), aiming and catching (-1.6, 95% CI-3.26 to -0.10) and manual dexterity (-2.8, 95% CI-4.64 to -0.85). The case group reported significantly higher median (IQR) total (12 [6.5-13.5] vs 6 [2.25-10], p=0.005) and emotional behavioural difficulties (2 [1-4.5] vs 0.5 [0-2.75], p=0.03) and more case children needed extra support in school (34%vs5%, p=0.02) than the control group. CONCLUSIONS: School-age children without CP cooled for HIE still have reduced cognitive and motor performance and more emotional difficulties than their peers, strongly supporting the need for school-age assessments.


Assuntos
Hipotermia Induzida , Hipóxia-Isquemia Encefálica/terapia , Transtornos do Neurodesenvolvimento/diagnóstico , Estudos de Casos e Controles , Criança , Transtornos do Comportamento Infantil/diagnóstico , Compreensão , Feminino , Seguimentos , Humanos , Recém-Nascido , Masculino , Memória de Curto Prazo , Destreza Motora , Testes Neuropsicológicos , Estudos Prospectivos , Desempenho Psicomotor , Reino Unido , Escalas de Wechsler
4.
Neural Netw ; 121: 242-258, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31581065

RESUMO

We present a framework based on iterative free-energy optimization with spiking neural networks for modeling the fronto-striatal system (PFC-BG) for the generation and recall of audio memory sequences. In line with neuroimaging studies carried out in the PFC, we propose a genuine coding strategy using the gain-modulation mechanism to represent abstract sequences based solely on the rank and location of items within them. Based on this mechanism, we show that we can construct a repertoire of neurons sensitive to the temporal structure in sequences from which we can represent any novel sequences. Free-energy optimization is then used to explore and to retrieve the missing indices of the items in the correct order for executive control and compositionality. We show that the gain-modulation mechanism permits the network to be robust to variabilities and to have long-term dependencies as it implements a gated recurrent neural network. This model, called Inferno Gate, is an extension of the neural architecture Inferno standing for Iterative Free-Energy Optimization of Recurrent Neural Networks with Gating or Gain-modulation. In experiments performed with an audio database of ten thousand MFCC vectors, Inferno Gate is capable of encoding efficiently and retrieving chunks of fifty items length. We then discuss the potential of our network to model the features of working memory in the PFC-BG loop for structural learning, goal-direction and hierarchical reinforcement learning.


Assuntos
Potenciais de Ação/fisiologia , Aprendizagem/fisiologia , Memória de Curto Prazo/fisiologia , Córtex Pré-Frontal/fisiologia , Humanos , Rememoração Mental/fisiologia , Neurônios/fisiologia
5.
J Sci Med Sport ; 23(1): 82-88, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31628001

RESUMO

OBJECTIVES: Cognitive skills such as working memory or inhibitory control are suggested to have an impact on injury risk during time-constrained athletic movements. Thus, the aim of this study was to gain further insights into the cognitive processes associated with biomechanical stability in unplanned jump-landings. DESIGN: Cross-sectional. METHODS: Twenty male participants (27±4years) performed 70 counter-movement jumps with single-leg landings on a pressure plate. Equally balanced and in randomized order, these were to be performed either planned (landing leg indicated before take-off) or unplanned (visual cue during flight). Biomechanical stability was estimated from vertical peak ground reaction force (pGRF), time to stabilization (TTS), center of pressure path length (COP), and the number of standing errors (ground touch with free leg). In addition, decision-making was assessed as the amount of landing errors (wrong/both feet) in the unplanned condition. Cognitiive function was measured using computerized as well as pen-and-paper-testing. RESULTS: Unplanned landings produced higher COP values (p<0.001, d=1.1) and more standing errors (p<0.001, d=0.9) than the pre-planned condition. Decreased postural stability (COP) was related to lower inhibitory control (p=0.036, r=0.48). There was a correlation between the increase in standing errors and better cognitive flexibility/working memory (p=0.037, r=-0.48) and short-term memory (p=0.028, r=0.50). The opposite was found for the unplanned landing errors: poor decision-making was associated with deficits in cognitive flexibility/working memory (p=0.022, r=0.54) and short-term memory (p=0.019, r=-0.55). CONCLUSIONS: Cognitive function may be an important, but under-researched moderator of unplanned jump-landing safety. Further research should elucidate the development of training methods aiming to improve movement-related decision-making and landing stability under time constraints.


Assuntos
Fenômenos Biomecânicos , Cognição , Equilíbrio Postural , Adulto , Estudos Transversais , Tomada de Decisões , Humanos , Masculino , Memória de Curto Prazo , Adulto Jovem
6.
Acta Psychol (Amst) ; 202: 102983, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31864214

RESUMO

It is unclear whether the effects of emotional state on working memory (WM) are valence-based or motivation-based since the type of emotions used in previous research differed on both dimensions of emotion. Especially, effects of anger, which is a negative but approach-related emotional state, were mostly overlooked. To distinguish between valence vs. motivation accounts, two experiments were conducted in which participants were induced one of four emotional states to create approach-positive (happiness), avoidance-negative (fear), approach-negative (anger), and control (neutral) conditions, followed by Self-ordered Pointing Task (Experiment 1) or N-Back task (Experiment 2) as WM measures. The main effect of emotion on WM accuracy was not significant in neither experiment. In the second experiment, however, reaction times (RTs) in the avoidance-related emotion condition were significantly faster compared to those in approach-related conditions, without compromising accuracy. Together the two experiments suggest that the motivational dimension of emotional state is more effective on WM than the valence dimension, especially on the RTs, indicating working memory updating efficiency.


Assuntos
Emoções/fisiologia , Memória de Curto Prazo/fisiologia , Motivação/fisiologia , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Adulto , Ira/fisiologia , Medo/fisiologia , Medo/psicologia , Feminino , Felicidade , Humanos , Masculino , Adulto Jovem
7.
Accid Anal Prev ; 134: 105334, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31689573

RESUMO

It has been widely agreed that it is risky for patients with diabetes to drive during hypoglycemia. However, driving during non-hypoglycemia may also bring certain safety hazards for some patients with diabetes. Based on previous studies on diabetes-related to early aging effect, as well as gender differences in health belief and driving behavior, we have hypothesized that middle-aged male drivers with type 2 diabetes, compared with the control healthy ones, may experience a decline in driving performance without awareness. And the decline is caused by impaired perceptual and cognitive driving-related functions. To verify these hypotheses, we recruited 56 non-professional male drivers aged between 40 and 60 (27 patients with type 2 diabetes and 29 healthy controls) to perform a simulated car-following task and finish behavioral tests of proprioception, visual search, and working memory abilities during non-hypoglycemia. They also reported their hypoglycemia experience and perceived driving skills. We found that the patients had equal confidence in their driving skills but worse driving performance as shown in larger centerline deviation (t = 2.83, p = .006), longer brake reaction time (t = 3.77, p = .001) and shorter minimum time-to-collision (t = -3.27, p = .002). Such between-group differences in driving performance could be fully mediated by proprioception, visual search ability, and working memory capacity but not by hypoglycemia experience. Regarding the effect sizes of the mediation, the visual search ability played the most important role, and then followed the working memory and the proprioception. This initial study provides original and first-hand evidence demonstrating that the middle-aged male drivers with type 2 diabetes have deteriorated driving performance, but they are unaware of it. We will also discuss the possible measures to identify people of the highest risk and improve their safety awareness by using the findings of the current study.


Assuntos
Condução de Veículo/psicologia , Cognição/fisiologia , Diabetes Mellitus Tipo 2/complicações , Autoimagem , Estudos de Casos e Controles , Simulação por Computador , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Pessoa de Meia-Idade , Tempo de Reação/fisiologia
8.
Health Psychol ; 39(1): 10-20, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31380682

RESUMO

OBJECTIVE: Distraction is a well-established pain management technique for children experiencing acute pain, although the mechanisms underlying the effectiveness of distraction are not well understood. It has been postulated that engagement of executive functions, such as working memory, may be a critical factor in attenuating pain via distraction. To test this hypothesis, we compared a 1-back task requiring engagement of working memory with a simple visual discrimination task demanding focused attention, but lower cognitive load (0-back). METHOD: Seventy-nine children (6-12 years old) underwent a baseline cold pressor trial followed by cold pressor trials in which they completed the visual discrimination and 1-back tasks in counterbalanced order. Executive functioning ability was assessed via the Wechsler Intelligence Scale for Children (5th Edition) working memory subscales and by parent report on the Behavior Rating Inventory of Executive Function, Second Edition (BRIEF®2). RESULTS: Children's pain tolerance improved in both the visual discrimination and 1-back conditions though a differential response to the 2 tasks was not observed. Age moderated the relation between executive functioning and response to distraction; older children with better executive functioning skills demonstrated greater improvements in both distraction interventions. CONCLUSIONS: Findings demonstrate the benefits of both visual discrimination and working memory distraction tasks for elementary-aged children experiencing acute pain. Further research is required in order to elucidate the role of executive functioning skills and cognitive load in enhancing distraction analgesia in children, with particular focus on determining optimal load and task difficulty in light of emerging executive functioning abilities in this age group. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
/fisiologia , Memória de Curto Prazo/fisiologia , Limiar da Dor/psicologia , Dor/psicologia , Criança , Feminino , Humanos , Masculino
9.
Neural Netw ; 121: 419-429, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31606611

RESUMO

The serial-position effect in working memory is considered important for studying how a sequence of sensory information can be retained and manipulated simultaneously in neural memory circuits. Here, via a precise analysis of the primacy and recency effects in human psychophysical experiments, we propose that stable and flexible codings take distinct roles of retaining and updating information in working memory, and that their combination induces serial-position effects spontaneously. We found that stable encoding retains memory to induce the primacy effect, while flexible encoding used for learning new inputs induces the recency effect. A model simulation based on human data, confirmed that a neural network with both flexible and stable synapses could reproduce the major characteristics of serial-position effects. Our new prediction, that the control of resource allocation by flexible-stable coding balance can modulate memory performance in sequence-specific manner, was supported by pre-cued memory performance data in humans.


Assuntos
Memória de Curto Prazo , Modelos Neurológicos , Encéfalo/fisiologia , Humanos
10.
Artigo em Russo | MEDLINE | ID: mdl-31793544

RESUMO

AIM: To assess spatial working memory disorders in patients with mild depressive disorders and determine their neurophysiological correlates. MATERIAL AND METHODS: Thirty patients (right-handed) with ICD-10 diagnosis Mood Disorders (F31.3, F32.0, F33.0, F34.1), aged 37±8 years, were examined before treatment. A control group included 30 mentally and somatically healthy individuals (32±7 years old). The study of spatial working memory was carried out using the Corsi Block-Tapping test. EEG was recorded and the values of the spectral power of theta, alpha and beta rhythms were analyzed. RESULTS AND CONCLUSION: A decrease in the level of working memory that was correlated with higher values of theta rhythm power in the frontal and occipital regions and alpha rhythm in the frontal cortex was observed in affective disorders with mild depressive symptoms.


Assuntos
Transtorno Depressivo , Transtornos da Memória , Memória de Curto Prazo , Adulto , Depressão , Transtorno Depressivo/complicações , Transtorno Depressivo/fisiopatologia , Eletroencefalografia , Humanos , Transtornos da Memória/complicações , Pessoa de Meia-Idade , Transtornos do Humor , Ritmo Teta
11.
Chimia (Aarau) ; 73(12): 1006-1011, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31883552

RESUMO

Drug discovery benefits from computational models aiding the identification of new chemical matter with bespoke properties. The field of de novo drug design has been particularly revitalized by adaptation of generative machine learning models from the field of natural language processing. These deep neural network models are trained on recognizing molecular structures and generate new molecular entities without relying on pre-determined sets of molecular building blocks and chemical transformations for virtual molecule construction. Implicit representation of chemical knowledge provides an alternative to formulating the molecular design task in terms of the established, explicit chemical vocabulary. Here, we review de novo molecular design approaches from the field of 'artificial intelligence', focusing on instances of deep generative models, and highlight the prospective application of long short-term memory models to hit and lead finding in medicinal chemistry.


Assuntos
Memória de Curto Prazo , Desenho de Drogas , Aprendizado de Máquina , Estudos Prospectivos
12.
Eat Behav ; 35: 101338, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31707244

RESUMO

A growing body of research has linked obesity to lower working memory performance. However, sex differences are often found in associations between obesity and cognition, and little work has examined potential sex differences in the association between obesity and working memory. To address this issue, the present research uses data from Wave IV of The National Longitudinal Study of Adolescent to Adult Health (N = 4,769, mean age = 29) to examine whether sex moderated the association between excess weight and working memory. As expected, we found that obesity was associated with poorer working memory, but-importantly-this association was exclusively seen in women, not men. These results held when treating BMI as a continuous or categorical variable (e.g., normal weight, obese), as well as with and without controlling for covariates. The present results therefore indicate that the association between obesity and poorer working memory performance may be sex-dependent. These results suggest that interventions targeted at reducing obesity should be tailored to an individual's sex, as adherence to these interventions often requires working memory.


Assuntos
Transtornos da Memória/epidemiologia , Memória de Curto Prazo/fisiologia , Obesidade/fisiopatologia , Obesidade/psicologia , Adulto , Conjuntos de Dados como Assunto , Feminino , Humanos , Estudos Longitudinais , Masculino , Distribuição por Sexo , Estados Unidos/epidemiologia
13.
Acta Psychol (Amst) ; 201: 102954, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31722258

RESUMO

Previous research suggests that the perception of stimulus onset can be accelerated by a match between the contents of visual working memory and the stimulus presented alone in the peripheral visual field. This onset acceleration effect might contribute to previously reported effects of working memory on perceived stimulus duration. However, it remains possible that the contents of visual working memory may also modulate the offset perception of matching visual stimuli, thereby contributing to the modulation of duration perception by working memory. The present study directly tested this possibility by using a simple reaction time task to assess the effect of visual working memory on perceived stimulus offset. Participants were asked to maintain a sample stimulus in working memory and subsequently had to respond to the offset of a single visual target. Across three experiments, we showed that the offset response was reliably slower when the target matched the sample held in visual working memory, as compared with when the target did not. This effect was not likely attributed to the mechanism of repetition priming from the presentation of the sample, because we failed to observe a priming effect either when the sample was only passively viewed without working memory demands or when the sample was initially encoded into memory but did not need to be actively maintained in mind by the time the offset target appeared. The findings provide direct evidence indicating that active maintenance of information in visual working memory delays the perceived offset of matching visual stimuli.


Assuntos
Memória de Curto Prazo/fisiologia , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Percepção Visual/fisiologia , Adulto , Atenção/fisiologia , Cognição/fisiologia , Feminino , Humanos , Masculino , Priming de Repetição/fisiologia , Adulto Jovem
14.
Artigo em Inglês | MEDLINE | ID: mdl-31717739

RESUMO

This study investigated the effects of a high intensity interval training (HIIT) program on both physical fitness and executive functions in children. Fifty-six children aged 8-12 years participated in this study, and were divided into a HIIT group and a control group. The HIIT group performed three sessions of the 8- to 10-min HIIT program per week for 4 weeks. Before and after the intervention, 20-m shuttle runs, sit-ups, and standing long jumps were assessed as test of physical fitness. In addition, the executive function was assessed using the digit span forward (DSF) test, digit span backward (DSB) test, and Tower of Hanoi test. Only the HIIT group experienced significant improvement when completing the 20-m shuttle run (p = 0.042) and sit-ups (p < 0.001). Regarding executive function, the number of correct answers in DSB test significantly increased only in the HIIT group (p = 0.003). However, the standing long jump, DSF, and the Tower of Hanoi test performance did not change after intervention. The findings of the present study suggest that HIIT has positive effects on a core executive function such as working memory in addition to components of the physical fitness such as cardiorespiratory endurance and muscular endurance.


Assuntos
Função Executiva , Treinamento Intervalado de Alta Intensidade , Criança , Feminino , Humanos , Masculino , Memória de Curto Prazo , Aptidão Física
15.
Nat Commun ; 10(1): 4900, 2019 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31653847

RESUMO

The tau protein aggregates in aging and Alzheimer disease and may lead to memory loss through disruption of medial temporal lobe (MTL)-dependent memory systems. Here, we investigated tau-mediated mechanisms of hippocampal dysfunction that underlie the expression of episodic memory decline using fMRI measures of hippocampal local coherence (regional homogeneity; ReHo), distant functional connectivity and tau-PET. We show that age and tau pathology are related to higher hippocampal ReHo. Functional disconnection between the hippocampus and other components of the MTL memory system, particularly an anterior-temporal network specialized for object memory, is also associated with higher hippocampal ReHo and greater tau burden in anterior-temporal regions. These associations are not observed in the posteromedial network, specialized for context/spatial information. Higher hippocampal ReHo predicts worse memory performance. These findings suggest that tau pathology plays a role in disconnecting the hippocampus from specific MTL memory systems leading to increased local coherence and memory decline.


Assuntos
Envelhecimento/metabolismo , Córtex Entorrinal/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Emaranhados Neurofibrilares/metabolismo , Lobo Temporal/diagnóstico por imagem , Proteínas tau/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Envelhecimento/psicologia , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/metabolismo , Compostos de Anilina , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Carbolinas , Envelhecimento Cognitivo/fisiologia , Envelhecimento Cognitivo/psicologia , Meios de Contraste , Córtex Entorrinal/metabolismo , Córtex Entorrinal/fisiopatologia , Função Executiva , Feminino , Neuroimagem Funcional , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Humanos , Masculino , Memória Episódica , Memória de Curto Prazo , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Vias Neurais/metabolismo , Vias Neurais/fisiopatologia , Tomografia por Emissão de Pósitrons , Lobo Temporal/metabolismo , Lobo Temporal/fisiologia , Tiazóis , Adulto Jovem
16.
PLoS Comput Biol ; 15(10): e1007380, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31658253

RESUMO

Cognitive development studies how information processing in the brain changes over the course of development. A key part of this question is how information is represented and stored in memory. This study examined allocentric (world-based) spatial memory, an important cognitive tool for planning routes and interacting with the space around us. This is typically theorized to use multiple landmarks all at once whenever it operates. In contrast, here we show that allocentric spatial memory frequently operates over a limited spatial window, much less than the full proximal scene, for children between 3.5 and 8.5 years old. The use of multiple landmarks increases gradually with age. Participants were asked to point to a remembered target location after a change of view in immersive virtual reality. A k-fold cross-validation model-comparison selected a model where young children usually use the target location's vector to the single nearest landmark and rarely take advantage of the vectors to other nearby landmarks. The comparison models, which attempt to explain the errors as generic forms of noise rather than encoding to a single spatial cue, did not capture the distribution of responses as well. Parameter fits of this new single- versus multi-cue model are also easily interpretable and related to other variables of interest in development (age, executive function). Based on this, we theorize that spatial memory in humans develops through three advancing levels (but not strict stages): most likely to encode locations egocentrically (relative to the self), then allocentrically (relative to the world) but using only one landmark, and finally, most likely to encode locations relative to multiple parts of the scene.


Assuntos
Percepção Espacial/fisiologia , Memória Espacial/fisiologia , Criança , Pré-Escolar , Cognição , Sinais (Psicologia) , Feminino , Humanos , Masculino , Memória/fisiologia , Memória de Curto Prazo/fisiologia , Modelos Teóricos , Estimulação Luminosa , Desempenho Psicomotor/fisiologia , Realidade Virtual
17.
BMC Infect Dis ; 19(1): 833, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31590634

RESUMO

BACKGROUND: Persistent symptoms attributed to Lyme borreliosis often include self-reported cognitive impairment. However, it remains unclear whether these symptoms can be substantiated by objective cognitive testing. METHODS: For this observational study, cognitive performance was assessed in 280 adults with persistent symptoms attributed to Lyme borreliosis (as part of baseline data collected for the Dutch PLEASE study). Cognitive testing covered the five major domains: episodic memory, working memory / attention, verbal fluency, information-processing speed and executive function. Patients' profiles of test scores were compared to a large age-, education- and sex-adjusted normative sample using multivariate normative comparison. Performance validity was assessed to detect suboptimal effort, and questionnaires were administered to measure self-reported cognitive complaints, fatigue, anxiety, depressive symptoms and several other psychological factors. RESULTS: Of 280 patients, one was excluded as the test battery could not be completed. Of the remaining 279 patients, 239 (85.4%) displayed sufficient performance validity. Patients with insufficient performance validity felt significantly more helpless and physically fatigued, and less orientated. Furthermore, they had a lower education level and less often paid work. Of the total study cohort 5.7% (n = 16) performed in the impaired range. Among the 239 patients who displayed sufficient performance validity, 2.9% (n = 7) were classified as cognitively impaired. No association between subjective cognitive symptoms and objective impairment was found. CONCLUSIONS: Only a small percentage of patients with borreliosis-attributed persistent symptoms have objective cognitive impairment. Performance validity should be taken into account in neuropsychological examinations of these patients. Self-report questionnaires are insufficiently valid to diagnose cognitive impairment. TRIAL REGISTRATION: ClinicalTrials.gov NCT01207739 . Registered 23 September 2010.


Assuntos
Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Doença de Lyme/complicações , Doença de Lyme/psicologia , Adulto , Ansiedade/diagnóstico , Atenção , Estudos de Coortes , Depressão/diagnóstico , Função Executiva , Fadiga/diagnóstico , Feminino , Humanos , Masculino , Memória Episódica , Memória de Curto Prazo , Pessoa de Meia-Idade , Testes Neuropsicológicos , Autorrelato
18.
Handb Clin Neurol ; 163: 197-219, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31590731

RESUMO

Executive functions (EFs) include high-order cognitive abilities such as working memory, inhibitory control, cognitive flexibility, planning, reasoning, and problem solving. EFs enable humans to achieve goals, adapt to novel everyday life situations, and manage social interactions. Traditionally EFs have been associated with frontal lobe functioning. More recent evidence shows that posterior and subcortical regions also play a crucial role in EF processing, especially in the integration of sensory information and emotion. This chapter reviews the variety of EFs and their neural underpinning, based on lesion mapping and neuroimaging studies, as well as the evidence for rehabilitation interventions, neuropsychological assessment based on standard and ecologically valid tests, development, and genetic predisposition for recovery of executive functions after brain injury. Taken together, the EFs are critical for unique human abilities and more careful analyses of their subcomponents may help the development of targeted translational interventions to improve them.


Assuntos
Cognição/fisiologia , Função Executiva/fisiologia , Lobo Frontal/fisiologia , Humanos , Memória de Curto Prazo/fisiologia , Testes Neuropsicológicos , Resolução de Problemas/fisiologia
19.
Handb Clin Neurol ; 163: 369-389, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31590742

RESUMO

Healthy aging is associated with numerous deficits in cognitive function, which have been attributed to changes within the prefrontal cortex (PFC). This chapter summarizes some of the most prominent cognitive changes associated with age-related alterations in the anatomy and physiology of the PFC. Specifically, aging of the PFC results in deficient aspects of cognitive control, including sustained attention, selective attention, inhibitory control, working memory, and multitasking abilities. Yet, not all cognitive functions associated with the PFC exhibit age-related declines, such as arithmetic, comprehension, emotion perception, and emotional control. Moreover, not all older adults exhibit declines in cognition. Multiple life-course and lifestyle factors, as well as genetics, play a role in the trajectory of cognitive performance across the life span. Thus many adults retain cognitive function well into advanced age. Moreover, the brain remains plastic throughout life and there is increasing evidence that most age-related declines in cognition can be remediated by various methods such as physical exercise, cognitive training, or noninvasive brain stimulation. Overall, because cognitive aging is associated with numerous life-course and lifestyle factors, successful aging likely begins in early life, while maintaining cognition or remediating declines is a life-long process.


Assuntos
Envelhecimento/fisiologia , Cognição/fisiologia , Função Executiva/fisiologia , Lobo Frontal/fisiologia , Atenção/fisiologia , Humanos , Memória de Curto Prazo/fisiologia
20.
Psychiatr Hung ; 34(3): 300-310, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31570661

RESUMO

This paper aims to review previous findings on the developmental trajectory of core executive functions - attentional control, inhibition, mental shifting, cognitive flexibility, and working memory - in adolescence with special attention to age-related stress-sensitivity in this period. More simple abilities, like attentional control and inhibition, go through a dramatic maturation process between the ages of 10 and 11. This is followed by a final progress, and as a result, after age 13-15 years acute stress deteriorates attentional control performance less, or it may even improve it. Working memory matures later, around 14-15 years, and it reaches the adult level at 17 years. Concerning mental shifting and cognitive flexibility, more maturation points could be identified: word fluency usually reaches full maturation at the age of 13, semantic fluency between the ages of 17 and 18, and general flexibility around 18-19 years. Based on the reviewed papers we could see that acute stress affects executive functions differently during adolescence, depending on how these functions mature. Those functions which develop later, are more sensitive to stress during the entire period of adolescence, and reviewed studies show that acute stress has a deteriorating effect on these functions. At the same time, early matured inhibition and attentional control are enhanced by acute stress in the half of the studies. Other theories and methodological issues are also discussed. Keywords: attentional control; inhibition; shifting; working memory.


Assuntos
Desenvolvimento Infantil , Função Executiva , Psicologia do Adolescente , Estresse Psicológico , Adolescente , Criança , Humanos , Memória de Curto Prazo , Adulto Jovem
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