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1.
Ideggyogy Sz ; 73(9-10): 327-337, 2020 Sep 30.
Artigo em Húngaro | MEDLINE | ID: mdl-33035416

RESUMO

Background and purpose: A growing body of evidence suggests that sleep plays an essential role in the consolidation of different memory systems, but less is known about the beneficial effect of sleep on relational memory processes and the recognition of emotional facial expressions, however, it is a fundamental cognitive skill in human everyday life. Thus, the study aims to investigate the effect of timing of learning and the role of sleep in relational memory processes. Methods: 84 young adults (average age: 22.36 (SD: 3.22), 21 male/63 female) participated in our study, divided into two groups: evening group and morning group indicating the time of learning. We used the face-name task to measure relational memory and facial expression recognition. There were two sessions for both groups: the immediate testing phase and the delayed retesting phase, separated by 24 hours. Results: 84 young adults (average age: 22.36 (SD: 3.22), 21 male/63 female) participated in our study, divided into two groups: evening group and morning group indicating the time of learning. We used the face-name task to measure relational memory and facial expression recognition. There were two sessions for both groups: the immediate testing phase and the delayed retesting phase, separated by 24 hours. Conclusion: Our results suggest that the timing of learning and sleep plays an important role in the stabilizing process of memory representation to resist against forgetting.


Assuntos
Aprendizagem/fisiologia , Memória/fisiologia , Sono/fisiologia , Adulto , Emoções , Expressão Facial , Reconhecimento Facial , Feminino , Humanos , Masculino , Adulto Jovem
2.
PLoS Comput Biol ; 16(9): e1008149, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32903264

RESUMO

Learning and generalization in spatial domains is often thought to rely on a "cognitive map", representing relationships between spatial locations. Recent research suggests that this same neural machinery is also recruited for reasoning about more abstract, conceptual forms of knowledge. Yet, to what extent do spatial and conceptual reasoning share common computational principles, and what are the implications for behavior? Using a within-subject design we studied how participants used spatial or conceptual distances to generalize and search for correlated rewards in successive multi-armed bandit tasks. Participant behavior indicated sensitivity to both spatial and conceptual distance, and was best captured using a Bayesian model of generalization that formalized distance-dependent generalization and uncertainty-guided exploration as a Gaussian Process regression with a radial basis function kernel. The same Gaussian Process model best captured human search decisions and judgments in both domains, and could simulate realistic learning curves, where we found equivalent levels of generalization in spatial and conceptual tasks. At the same time, we also find characteristic differences between domains. Relative to the spatial domain, participants showed reduced levels of uncertainty-directed exploration and increased levels of random exploration in the conceptual domain. Participants also displayed a one-directional transfer effect, where experience in the spatial task boosted performance in the conceptual task, but not vice versa. While confidence judgments indicated that participants were sensitive to the uncertainty of their knowledge in both tasks, they did not or could not leverage their estimates of uncertainty to guide exploration in the conceptual task. These results support the notion that value-guided learning and generalization recruit cognitive-map dependent computational mechanisms in spatial and conceptual domains. Yet both behavioral and model-based analyses suggest domain specific differences in how these representations map onto actions.


Assuntos
Tomada de Decisões/fisiologia , Aprendizagem/fisiologia , Modelos Psicológicos , Adulto , Algoritmos , Teorema de Bayes , Biologia Computacional , Feminino , Humanos , Masculino , Recompensa , Incerteza
3.
PLoS One ; 15(9): e0238454, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32966302

RESUMO

In this work, we present a local intrinsic rule that we developed, dubbed IP, inspired by the Infomax rule. Like Infomax, this rule works by controlling the gain and bias of a neuron to regulate its rate of fire. We discuss the biological plausibility of the IP rule and compare it to batch normalisation. We demonstrate that the IP rule improves learning in deep networks, and provides networks with considerable robustness to increases in synaptic learning rates. We also sample the error gradients during learning and show that the IP rule substantially increases the size of the gradients over the course of learning. This suggests that the IP rule solves the vanishing gradient problem. Supplementary analysis is provided to derive the equilibrium solutions that the neuronal gain and bias converge to using our IP rule. An analysis demonstrates that the IP rule results in neuronal information potential similar to that of Infomax, when tested on a fixed input distribution. We also show that batch normalisation also improves information potential, suggesting that this may be a cause for the efficacy of batch normalisation-an open problem at the time of this writing.


Assuntos
Aprendizagem/fisiologia , Redes Neurais de Computação , Plasticidade Neuronal/fisiologia , Potenciais de Ação/fisiologia , Algoritmos , Simulação por Computador , Aprendizado Profundo/tendências , Modelos Neurológicos , Modelos Estatísticos , Modelos Teóricos , Neurônios/fisiologia , Sinapses/fisiologia , Transmissão Sináptica/fisiologia
4.
Life Sci ; 260: 118388, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32890602

RESUMO

Damage to the cholinergic system in central nervous system injuries such as traumatic brain injury (TBI) and neurodegenerative diseases leads to impaired learning and cognition. Neural stem cells (NSCs) have self-renewal capacity and multi-directional differentiation potential and considered the best source of cells for cell replacement therapy. However, how to promote the differentiation of NSCs into neurons is a major challenge in current research. Lhx8 has a specific effect on the development of the cholinergic nervous system, but its exact function is unclear. In this study, we found that Lhx8 could regulate the expression of Growth arrest-specific (GAS)5 which has been implicated in cancer but was less studied in the nervous system. Additionally, results from PCR, fluorescence in situ hybridization, and immunocytochemical analyses showed that GAS5 is mainly expressed in the cytoplasm of hippocampal neural stems cells and promotes their differentiation into neurons; the Morris water maze test demonstrated that GAS5 overexpression restored learning and memory in rats with cholinergic injury. These findings indicate that GAS5, which is regulated by Lhx8, improve brain function following cholinergic nerve injury.


Assuntos
Lesões Encefálicas/fisiopatologia , Neurônios Colinérgicos/patologia , Proteínas com Homeodomínio LIM/metabolismo , Aprendizagem/fisiologia , Memória/fisiologia , Células-Tronco Neurais/patologia , RNA Longo não Codificante/genética , Fatores de Transcrição/metabolismo , Acetilcolina/metabolismo , Animais , Colina O-Acetiltransferase/metabolismo , Neurônios Colinérgicos/metabolismo , Regulação da Expressão Gênica , Proteínas com Homeodomínio LIM/genética , Células-Tronco Neurais/metabolismo , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Fatores de Transcrição/genética
5.
Proc Natl Acad Sci U S A ; 117(38): 23886-23897, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32900934

RESUMO

Motor skill learning involves a complex process of generating novel movement patterns guided by evaluative feedback, such as a reward. Previous literature has suggested anteroposteriorly separated circuits in the striatum to be implicated in early goal-directed and later automatic stages of motor skill learning, respectively. However, the involvement of these circuits has not been well elucidated in human de novo motor skill learning, which requires learning arbitrary action-outcome associations and value-based action selection. To investigate this issue, we conducted a human functional MRI (fMRI) experiment in which participants learned to control a computer cursor by manipulating their right fingers. We discovered a double dissociation of fMRI activity in the anterior and posterior caudate nucleus, which was associated with performance in the early and late learning stages. Moreover, cognitive and sensorimotor cortico-caudate interactions predicted individual learning performance. Our results suggest parallel cortico-caudate networks operating in different stages of human de novo motor skill learning.


Assuntos
Núcleo Caudado/diagnóstico por imagem , Núcleo Caudado/fisiologia , Aprendizagem/fisiologia , Imagem por Ressonância Magnética , Destreza Motora/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
6.
Proc Natl Acad Sci U S A ; 117(38): 23898-23903, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32900965

RESUMO

Recent evidence suggests that gains in performance observed while humans learn a novel motor sequence occur during the quiet rest periods interleaved with practice (micro-offline gains, MOGs). This phenomenon is reminiscent of memory replay observed in the hippocampus during spatial learning in rodents. Whether the hippocampus is also involved in the production of MOGs remains currently unknown. Using a multimodal approach in humans, here we show that activity in the hippocampus and the precuneus increases during the quiet rest periods and predicts the level of MOGs before asymptotic performance is achieved. These functional changes were followed by rapid alterations in brain microstructure in the order of minutes, suggesting that the same network that reactivates during the quiet periods of training undergoes structural plasticity. Our work points to the involvement of the hippocampal system in the reactivation of procedural memories.


Assuntos
Hipocampo/fisiologia , Aprendizagem/fisiologia , Destreza Motora/fisiologia , Adolescente , Adulto , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Memória , Adulto Jovem
7.
Phys Rev Lett ; 125(8): 088103, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32909804

RESUMO

The ability of humans and animals to quickly adapt to novel tasks is difficult to reconcile with the standard paradigm of learning by slow synaptic weight modification. Here, we show that fixed-weight neural networks can learn to generate required dynamics by imitation. After appropriate weight pretraining, the networks quickly and dynamically adapt to learn new tasks and thereafter continue to achieve them without further teacher feedback. We explain this ability and illustrate it with a variety of target dynamics, ranging from oscillatory trajectories to driven and chaotic dynamical systems.


Assuntos
Aprendizagem/fisiologia , Modelos Neurológicos , Neurônios/fisiologia , Animais , Comunicação Celular/fisiologia , Humanos , Rede Nervosa/citologia , Rede Nervosa/fisiologia , Neurônios/citologia
8.
Nat Commun ; 11(1): 4358, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32868768

RESUMO

Learned fear and safety are associated with distinct oscillatory states in the basolateral amygdala (BLA) and medial prefrontal cortex (mPFC). To determine if and how these network states support the retrieval of competing memories, we mimicked endogenous oscillatory activity through optogenetic stimulation of parvalbumin-expressing interneurons in mice during retrieval of contextual fear and extinction memories. We found that exogenously induced 4 Hz and 8 Hz oscillatory activity in the BLA exerts bi-directional control over conditioned freezing behavior in an experience- and context-specific manner, and that these oscillations have an experience-dependent ability to recruit distinct functional neuronal ensembles. At the network level we demonstrate, via simultaneous manipulation of BLA and mPFC, that experience-dependent 4 Hz resonance across BLA-mPFC circuitry supports post-extinction fear memory retrieval. Our findings reveal that post-extinction fear memory retrieval is supported by local and interregional experience-dependent resonance, and suggest novel approaches for interrogation and therapeutic manipulation of acquired fear circuitry.


Assuntos
Tonsila do Cerebelo/fisiologia , Extinção Psicológica , Medo/fisiologia , Memória/fisiologia , Animais , Complexo Nuclear Basolateral da Amígdala/fisiologia , Condicionamento Psicológico , Eletrofisiologia/métodos , Aprendizagem/fisiologia , Camundongos , Optogenética/métodos , Córtex Pré-Frontal/fisiologia
9.
Nat Commun ; 11(1): 4217, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32868778

RESUMO

The cerebellum plays a crucial role in sensorimotor and associative learning. However, the contribution of molecular layer interneurons (MLIs) to these processes is not well understood. We used two-photon microscopy to study the role of ensembles of cerebellar MLIs in a go-no go task where mice obtain a sugar water reward if they lick a spout in the presence of the rewarded odorant and avoid a timeout when they refrain from licking for the unrewarded odorant. In naive animals the MLI responses did not differ between the odorants. With learning, the rewarded odorant elicited a large increase in MLI calcium responses, and the identity of the odorant could be decoded from the differential response. Importantly, MLIs switched odorant responses when the valence of the stimuli was reversed. Finally, mice took a longer time to refrain from licking in the presence of the unrewarded odorant and had difficulty becoming proficient when MLIs were inhibited by chemogenetic intervention. Our findings support a role for MLIs in learning valence in the cerebellum.


Assuntos
Cerebelo/fisiologia , Condicionamento Operante/fisiologia , Interneurônios/fisiologia , Aprendizagem/fisiologia , Células de Purkinje/fisiologia , Algoritmos , Animais , Cerebelo/citologia , Feminino , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia de Fluorescência por Excitação Multifotônica , Modelos Neurológicos , Odorantes , Recompensa , Fatores de Tempo
10.
Nat Commun ; 11(1): 4361, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32868773

RESUMO

The sensory responses of cortical neuronal populations following training have been extensively studied. However, the spike firing properties of individual cortical neurons following training remain unknown. Here, we have combined two-photon Ca2+ imaging and single-cell electrophysiology in awake behaving mice following auditory associative training. We find a sparse set (~5%) of layer 2/3 neurons in the primary auditory cortex, each of which reliably exhibits high-rate prolonged burst firing responses to the trained sound. Such bursts are largely absent in the auditory cortex of untrained mice. Strikingly, in mice trained with different multitone chords, we discover distinct subsets of neurons that exhibit bursting responses specifically to a chord but neither to any constituent tone nor to the other chord. Thus, our results demonstrate an integrated representation of learned complex sounds in a small subset of cortical neurons.


Assuntos
Córtex Auditivo/fisiologia , Percepção Auditiva/fisiologia , Neurônios/fisiologia , Estimulação Acústica/métodos , Córtex Auditivo/citologia , Sinalização do Cálcio , Eletrofisiologia/métodos , Aprendizagem/fisiologia , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Neurônios/metabolismo , Análise de Célula Única/métodos
11.
Nat Commun ; 11(1): 4669, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938940

RESUMO

The prefrontal cortex and striatum form a recurrent network whose spiking activity encodes multiple types of learning-relevant information. This spike-encoded information is evident in average firing rates, but finer temporal coding might allow multiplexing and enhanced readout across the connected network. We tested this hypothesis in the fronto-striatal network of nonhuman primates during reversal learning of feature values. We found that populations of neurons encoding choice outcomes, outcome prediction errors, and outcome history in their firing rates also carry significant information in their phase-of-firing at a 10-25 Hz band-limited beta frequency at which they synchronize across lateral prefrontal cortex, anterior cingulate cortex and anterior striatum when outcomes were processed. The phase-of-firing code exceeds information that can be obtained from firing rates alone and is evident for inter-areal connections between anterior cingulate cortex, lateral prefrontal cortex and anterior striatum. For the majority of connections, the phase-of-firing information gain is maximal at phases of the beta cycle that were offset from the preferred spiking phase of neurons. Taken together, these findings document enhanced information of three important learning variables at specific phases of firing in the beta cycle at an inter-areally shared beta oscillation frequency during goal-directed behavior.


Assuntos
Corpo Estriado/fisiologia , Giro do Cíngulo/fisiologia , Aprendizagem/fisiologia , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Animais , Análise por Conglomerados , Corpo Estriado/citologia , Sincronização de Fases em Eletroencefalografia , Eletrofisiologia/métodos , Eletrofisiologia/estatística & dados numéricos , Giro do Cíngulo/citologia , Macaca mulatta , Masculino , Rede Nervosa , Córtex Pré-Frontal/citologia , Recompensa
12.
PLoS One ; 15(9): e0239032, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32925937

RESUMO

Knowing where our limbs are in space is essential for moving and for adapting movements to various changes in our environments and bodies. The ability to adapt movements declines with age, and age-related cognitive decline can explain a decreased ability to adopt and deploy explicit, cognitive strategies in motor learning. Age-related sensory decline could also lead to a reduced fidelity of sensory position signals and error signals, each of which can affect implicit motor adaptation. Here we investigate two estimates of limb position; one based on proprioception, the other on predicted sensory consequences of movements. Each is considered a measure of an implicit adaptation process and may be affected by both age and cognitive strategies. Both older (n = 38) and younger (n = 42) adults adapted to a 30° visuomotor rotation in a centre-out reaching task. We make an explicit, cognitive strategy available to half of participants in each age group with a detailed instruction. After training, we first quantify the explicit learning elicited by instruction. Instructed older adults initially use the provided strategy slightly less than younger adults but show a similar ability to evoke it after training. This indicates that cognitive explanations for age-related decline in motor learning are limited. In contrast, training induced much larger shifts of state estimates of hand location in older adults compared to younger adults. This is not modulated by strategy instructions, and appears driven by recalibrated proprioception, which is almost twice as large in older adults, while predictions might not be updated in older adults. This means that in healthy aging, some implicit processes may be compensating for other changes to maintain motor capabilities, while others also show age-related decline (data: https://osf.io/qzhmy).


Assuntos
Fatores Etários , Atividade Motora/fisiologia , Desempenho Psicomotor/fisiologia , Adaptação Fisiológica/fisiologia , Adaptação Psicológica/fisiologia , Idoso , Feminino , Mãos/fisiologia , Humanos , Aprendizagem/fisiologia , Masculino , Movimento , Propriocepção , Rotação , Adulto Jovem
13.
PLoS One ; 15(9): e0239471, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32946493

RESUMO

Humans can innately track a moving target by anticipating its future position from a brief history of observations. While ballistic trajectories can be readily extrapolated, many natural and artificial systems are governed by more general nonlinear dynamics and, therefore, can produce highly irregular motion. Yet, relatively little is known regarding the behavioral and physiological underpinnings of prediction and tracking in the presence of chaos. Here, we investigated in lab settings whether participants could manually follow the orbit of a paradigmatic chaotic system, the Rössler equations, on the (x,y) plane under different settings of a control parameter, which determined the prominence of transients in the target position. Tracking accuracy was negatively related to the level of unpredictability and folding. Nevertheless, while participants initially reacted to the transients, they gradually learned to anticipate it. This was accompanied by a decrease in muscular co-contraction, alongside enhanced activity in the theta and beta EEG bands for the highest levels of chaoticity. Furthermore, greater phase synchronization of breathing was observed. Taken together, these findings point to the possible ability of the nervous system to implicitly learn topological regularities even in the context of highly irregular motion, reflecting in multiple observables at the physiological level.


Assuntos
Dinâmica não Linear , Análise e Desempenho de Tarefas , Adulto , Sistema Nervoso Autônomo/fisiologia , Fenômenos Biomecânicos/fisiologia , Eletroencefalografia , Eletromiografia , Força da Mão/fisiologia , Humanos , Cinética , Aprendizagem/fisiologia , Movimento (Física) , Contração Muscular/fisiologia , Adulto Jovem
14.
Nat Commun ; 11(1): 4503, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908145

RESUMO

Most humans believe in a god, but many do not. Differences in belief have profound societal impacts. Anthropological accounts implicate bottom-up perceptual processes in shaping religious belief, suggesting that individual differences in these processes may help explain variation in belief. Here, in findings replicated across socio-religiously disparate samples studied in the U.S. and Afghanistan, implicit learning of patterns/order within visuospatial sequences (IL-pat) in a strongly bottom-up paradigm predict 1) stronger belief in an intervening/ordering god, and 2) increased strength-of-belief from childhood to adulthood, controlling for explicit learning and parental belief. Consistent with research implicating IL-pat as a basis of intuition, and intuition as a basis of belief, mediation models support a hypothesized effect pathway whereby IL-pat leads to intuitions of order which, in turn, lead to belief in ordering gods. The universality and variability of human IL-pat may thus contribute to the global presence and variability of religious belief.


Assuntos
Comparação Transcultural , Intuição/fisiologia , Aprendizagem/fisiologia , Religião e Psicologia , Religião , Adolescente , Adulto , Afeganistão , Feminino , Humanos , Individualidade , Masculino , Inquéritos e Questionários/estatística & dados numéricos , Estados Unidos , Adulto Jovem
15.
Nat Commun ; 11(1): 4783, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32963219

RESUMO

Relations between task elements often follow hidden underlying structural forms such as periodicities or hierarchies, whose inferences fosters performance. However, transferring structural knowledge to novel environments requires flexible representations that are generalizable over particularities of the current environment, such as its stimuli and size. We suggest that humans represent structural forms as abstract basis sets and that in novel tasks, the structural form is inferred and the relevant basis set is transferred. Using a computational model, we show that such representation allows inference of the underlying structural form, important task states, effective behavioural policies and the existence of unobserved state-trajectories. In two experiments, participants learned three abstract graphs during two successive days. We tested how structural knowledge acquired on Day-1 affected Day-2 performance. In line with our model, participants who had a correct structural prior were able to infer the existence of unobserved state-trajectories and appropriate behavioural policies.


Assuntos
Cognição/fisiologia , Conhecimento , Análise e Desempenho de Tarefas , Tomada de Decisões , Humanos , Aprendizagem/fisiologia , Modelos Teóricos
16.
Nat Commun ; 11(1): 4057, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792523

RESUMO

Mammalian cortex has both local and cross-area connections, suggesting vital roles for both local and cross-area neural population dynamics in cortically-dependent tasks, like movement learning. Prior studies of movement learning have focused on how single-area population dynamics change during short-term adaptation. It is unclear how cross-area dynamics contribute to movement learning, particularly long-term learning and skill acquisition. Using simultaneous recordings of rodent motor (M1) and premotor (M2) cortex and computational methods, we show how cross-area activity patterns evolve during reach-to-grasp learning in rats. The emergence of reach-related modulation in cross-area activity correlates with skill acquisition, and single-trial modulation in cross-area activity predicts reaction time and reach duration. Local M2 neural activity precedes local M1 activity, supporting top-down hierarchy between the regions. M2 inactivation preferentially affects cross-area dynamics and behavior, with minimal disruption of local M1 dynamics. Together, these results indicate that cross-area population dynamics are necessary for learned motor skills.


Assuntos
Aprendizagem/fisiologia , Córtex Motor/fisiologia , Animais , Eletrofisiologia , Masculino , Neurofisiologia , Dinâmica Populacional , Ratos , Tempo de Reação/fisiologia
17.
Proc Natl Acad Sci U S A ; 117(37): 22760-22770, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32859755

RESUMO

Memory is typically thought of as enabling reminiscence about past experiences. However, memory also informs and guides processing of future experiences. These two functions of memory are often at odds: Remembering specific experiences from the past requires storing idiosyncratic properties that define particular moments in space and time, but by definition such properties will not be shared with similar situations in the future and thus may not be applicable to future situations. We discovered that, when faced with this conflict, the brain prioritizes prediction over encoding. Behavioral tests of recognition and source recall showed that items allowing for prediction of what will appear next based on learned regularities were less likely to be encoded into memory. Brain imaging revealed that the hippocampus was responsible for this interference between statistical learning and episodic memory. The more that the hippocampus predicted the category of an upcoming item, the worse the current item was encoded. This competition may serve an adaptive purpose, focusing encoding on experiences for which we do not yet have a predictive model.


Assuntos
Hipocampo/metabolismo , Aprendizagem/fisiologia , Memória Episódica , Adulto , Encéfalo/metabolismo , Mapeamento Encefálico/métodos , Feminino , Hipocampo/fisiologia , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Rememoração Mental/fisiologia , Reconhecimento Psicológico/fisiologia
18.
PLoS One ; 15(7): e0236416, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735572

RESUMO

Proprioception acquires a crucial role in estimating the configuration of our body segments in space when visual information is not available. Proprioceptive accuracy is assessed by asking participants to match the perceived position of an unseen body landmark through reaching movements. This task was also adopted to study the perceived hand structure by computing the relative distances between averaged proprioceptive judgments (hand Localization Task). However, the pattern of proprioceptive errors leading to the misperceived hand structure is unexplored. Here, we aimed to characterize this pattern across different hand landmarks, having different anatomo-physiological properties and cortical representations. Furthermore, we sought to describe the error consistency and its stability over time. To this purpose, we analyzed the proprioceptive errors of 43 healthy participants during the hand Localization Task. We found larger but more consistent errors for the fingertips compared to the knuckles, possibly due to poorer proprioceptive signal, compensated by other sources of spatial information. Furthermore, we found a shift (overlap effect) and a temporal drift of the hand perceived position towards the shoulder of origin, which was consistent within and between subjects. The overlap effect had a greater influence on lateral compared to medial landmarks, leading to the hand width overestimation. Our results are compatible with domain-general and body-specific spatial biases affecting the proprioceptive localization of the hand landmarks, thus the apparent hand structure misperception.


Assuntos
Mãos/fisiologia , Movimento/fisiologia , Propriocepção/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Feminino , Dedos/fisiologia , Corpo Humano , Humanos , Julgamento , Aprendizagem/fisiologia , Masculino , Polegar/fisiologia , Percepção Visual/fisiologia , Adulto Jovem
19.
PLoS One ; 15(8): e0219233, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790667

RESUMO

Our aim was to examine the effect of a smartphone's presence on learning and memory among undergraduates. A total of 119 undergraduates completed a memory task and the Smartphone Addiction Scale (SAS). As predicted, those without smartphones had higher recall accuracy compared to those with smartphones. Results showed a significant negative relationship between phone conscious thought, "how often did you think about your phone", and memory recall but not for SAS and memory recall. Phone conscious thought significantly predicted memory accuracy. We found that the presence of a smartphone and high phone conscious thought affects one's memory learning and recall, indicating the negative effect of a smartphone proximity to our learning and memory.


Assuntos
Telefone Celular/tendências , Aprendizagem/fisiologia , Memória/fisiologia , Atenção/fisiologia , Cognição , Dependência Psicológica , Feminino , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Smartphone , Estudantes , Inquéritos e Questionários , Adulto Jovem
20.
Science ; 369(6507)2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32855307

RESUMO

Everyday life often requires arbitrating between pursuing an ongoing action plan by possibly adjusting it versus exploring a new action plan instead. Resolving this so-called exploitation-exploration dilemma involves the medial prefrontal cortex (mPFC). Using human intracranial electrophysiological recordings, we discovered that neural activity in the ventral mPFC infers and tracks the reliability of the ongoing plan to proactively encode upcoming action outcomes as either learning signals or potential triggers to explore new plans. By contrast, the dorsal mPFC exhibits neural responses to action outcomes, which results in either improving or abandoning the ongoing plan. Thus, the mPFC resolves the exploitation-exploration dilemma through a two-stage, predictive coding process: a proactive ventromedial stage that constructs the functional signification of upcoming action outcomes and a reactive dorsomedial stage that guides behavior in response to action outcomes.


Assuntos
Comportamento Exploratório/fisiologia , Aprendizagem/fisiologia , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/citologia
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