Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 508
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Acta Psychol (Amst) ; 199: 102895, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31377309

RESUMO

Spatial abilities associated with success in educational and occupational fields of Science, Technology, Engineering, and Mathematics (STEM) have been repeatedly shown to be gendered, with males demonstrating measurably better spatial abilities than females. Less is known about why this is, or about how experience with spatial systems (videogames, for example) affects these abilities. We conducted two experiments with 82 participants with varying degrees of videogame experience on measures of mental rotation, spatial learning, and spatial memory. Spatial learning and memory were tested in a Virtual Morris Water Maze. In the first experiment, the maze lacked proximal landmarks. Males proved faster and more accurate than females in learning the location of the hidden platform. As predicted males also outperformed females in mental rotation abilities. Mental rotation correlated with performance in the virtual maze, indicating that in the absence of proximal landmarks, participants relied on strategies requiring mental rotation. Experienced 3D videogame players did not demonstrate superior spatial learning and memory, but performed better than novices in mental rotation. In the second experiment, the maze had proximal cues, in the form of landmarks on the circumference of the virtual pool, and gender-based differences in navigational performance significantly diminished. Under these changed environmental conditions, mental rotation ability did not correlate with performance in the VMWM, suggesting that given proximal cues, the need for mental rotation diminishes. Differences between videogame novices and experts also decreased when proximal cues were provided. Females in particular obtained more discernible benefits from videogame experience. Together, these experiments reveal how the spatial abilities and strategies used to solve the Morris maze task vary with environmental design. Given the structural similarities between the virtual maze and videogame environments, these results offer insight into how spatial experience gained through videogame playing can affect aspects of spatial cognition, and can help identify design elements that contribute to their improvement.


Assuntos
Percepção Espacial/fisiologia , Aprendizagem Espacial/fisiologia , Jogos de Vídeo/psicologia , Realidade Virtual , Adolescente , Adulto , Feminino , Humanos , Masculino , Aprendizagem em Labirinto/fisiologia , Fatores Sexuais , Memória Espacial/fisiologia , Navegação Espacial/fisiologia , Adulto Jovem
2.
Brain Cogn ; 135: 103576, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31203022

RESUMO

One of two memory systems can be used to navigate in a new environment. Hippocampus-dependent spatial strategy consists of creating a cognitive map of an environment and caudate nucleus-dependent response strategy consists of memorizing a rigid sequence of turns. Spontaneous use of the response strategy is associated with greater activity and grey matter within the caudate nucleus while the spatial strategy is associated with greater activity and grey matter in the hippocampus. The caudate nucleus is involved in executive functions such as working memory, cognitive control and certain aspects of attention such as attentional disengaging. This study therefore aimed to investigate whether response learners would display better performance on tests of executive and attention functioning compared to spatial learners. Fifty participants completed the 4/8 virtual maze to assess navigational strategy, the forward and backward visual digit span and the Attention Network Test - Revised to assess both attention disengagement and cognitive control. Results revealed that response learners showed significantly higher working memory capacity, more efficient attention disengagement and better cognitive control. Results suggest that response learners, who putatively display more grey matter and activity in the caudate nucleus, are associated with better working memory span, cognitive control and attentional disengagement.


Assuntos
Atenção/fisiologia , Núcleo Caudado/fisiologia , Memória de Curto Prazo/fisiologia , Aprendizagem Espacial/fisiologia , Navegação Espacial/fisiologia , Adolescente , Adulto , Cognição/fisiologia , Função Executiva/fisiologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Adulto Jovem
3.
Exp Brain Res ; 237(8): 1993-2010, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31154461

RESUMO

Early life stress is known to influence affective and cognitive functions in later life but comprehensive explanation for the impact of early life stress on attentional functions, behavioural control and social behaviour is inadequate. The early life stress was induced by exposing rat pups to 6 h of maternal separation and isolation (MS) stress from postnatal days 4-14 i.e. during SHRP period. The long-term impact of MS in these rats was evaluated by assessing anxiety, sociability, social preference, spatial learning and memory along with a detailed evaluation of attentional functions during young adulthood period. Adult male MS rats showed increased anxiety-like behaviour, impaired flexibility in social interactions, and increased reward-seeking behaviour. MS rats also showed faster spatial learning in the partially baited radial arm maze and exhibited moderately enhanced sustained attention in the 5-choice serial reaction time task (5CSRTT). These results suggest that early MS has both positive and negative consequences in adulthood. Increased cognitive ability in MS rats, as evidenced by the improved sustained attention and spatial learning and memory, is usually advantageous and indicates positive influences of early stressors that might lead to the development of resilience and enhanced compensatory mechanisms later in adulthood. MS stress has compromised flexibility in social behaviour that promotes solitary lifestyle and social isolation. Heightened reward-seeking behaviour, as shown by the MS rats, could be a predisposing factor for substance abuse and addiction. Thus, our study highlights the crucial and differential impact of early life challenges on behaviour during adulthood and suggests that the positive aspects could be an asset that may be utilized to suppress the negative effects of early life stress in adulthood.


Assuntos
Atenção/fisiologia , Relações Interpessoais , Privação Materna , Aprendizagem Espacial/fisiologia , Estresse Psicológico/psicologia , Animais , Animais Recém-Nascidos , Ansiedade/psicologia , Feminino , Masculino , Gravidez , Ratos , Ratos Wistar , Comportamento Social , Fatores de Tempo
4.
Brain Cogn ; 135: 103578, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31233961

RESUMO

Cystinosis is a rare genetic lysosomal storage disorder characterized by the accumulation of cystine in lysosomes. Many organ systems are vulnerable to this cystine accumulation including the CNS. A past study demonstrated that children with cystinosis have deficits in visual learning and memory while their verbal learning and memory and global intellectual function are spared (Spilkin, Ballantyne, & Trauner, 2009). However, no related study has been performed to assess the dissociation between visual and verbal learning and memory in adults with cystinosis who have had the benefit of longterm treatment with the cystine-depleting agent, cysteamine. In this study we assessed visual and verbal learning and memory in 15 adults with cystinosis, with a mean age of 30.2 years. The results indicate that adults with cystinosis have no significant deficits in either verbal or visual learning and memory. However, the individuals did perform better on the verbal assessment. The results suggest that if early and continued treatment is given to individuals with cystinosis there is a relative sparing of visual learning and memory that might have otherwise declined. This emphasizes the essential nature of the proper clinical management of cystinosis.


Assuntos
Cistinose/psicologia , Memória/fisiologia , Aprendizagem Verbal/fisiologia , Adulto , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Aprendizagem Espacial/fisiologia
5.
PLoS Comput Biol ; 15(6): e1007093, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31233559

RESUMO

Humans and other animals are able to discover underlying statistical structure in their environments and exploit it to achieve efficient and effective performance. However, such structure is often difficult to learn and use because it is obscure, involving long-range temporal dependencies. Here, we analysed behavioural data from an extended experiment with rats, showing that the subjects learned the underlying statistical structure, albeit suffering at times from immediate inferential imperfections as to their current state within it. We accounted for their behaviour using a Hidden Markov Model, in which recent observations are integrated with evidence from the past. We found that over the course of training, subjects came to track their progress through the task more accurately, a change that our model largely attributed to improved integration of past evidence. This learning reflected the structure of the task, decreasing reliance on recent observations, which were potentially misleading.


Assuntos
Modelos Biológicos , Recompensa , Aprendizagem Espacial/fisiologia , Animais , Comportamento Animal/fisiologia , Biologia Computacional , Ratos , Análise e Desempenho de Tarefas
6.
J Fish Biol ; 95(3): 870-880, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31254401

RESUMO

We tested the prediction that a complex physical rearing environment would enhance short-term spatial memory as assessed by learning ability in a spatial navigation task in juvenile Chinook salmon Oncorhynchus tshawytscha. We reared fish in two low-density treatments, where fish were either in bare fiberglass tanks (bare) or in tanks with physical structure (complex). We also tested conventionally reared high-density hatchery fish to compare with these other experimental treatments. Our reason for including this third hatchery treatment is that the two low-density treatments, aside from the manipulation of structure, followed a rearing programme that is designed to produce fish with more wild-like characteristics. We tested individually marked fish for seven consecutive days and recorded movement and time to exit a testing maze. Stimulus conspecific fish outside the exit of the maze provided positive reinforcement for test fish. Fish from the bare treatment were less likely to exit the start box compared with fish in the complex and hatchery treatments. However, fish in the hatchery treatment were significantly more likely to exit the maze on their own compared with both the bare and complex treatments. Hatchery fish effectively learned the task as shown by a decrease in the number of mistakes over time, but the number of mistakes was significantly greater on the first day of trials. Increasing habitat complexity with structure may not necessarily promote spatial learning ability, but differences between hatchery and experimental treatments in rearing density and motivation to be near conspecifics likely led to observed behavioural differences.


Assuntos
Criação de Animais Domésticos , Pesqueiros , Salmão/fisiologia , Aprendizagem Espacial/fisiologia , Animais
7.
Braz J Med Biol Res ; 52(5): e8026, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31038577

RESUMO

Carassius auratus is a teleost fish that has been largely used in behavioral studies. However, little is known about potential environmental influences on its performance of learning and memory tasks. Here, we investigated this question in C. auratus, and searched for potential correlation between exercise and visuospatial enrichment with the total number of telencephalic glia and neurons. To that end, males and females were housed for 183 days in either an enriched (EE) or impoverished environment (IE) aquarium. EE contained toys, natural plants, and a 12-hour/day water stream for voluntary exercise, whereas the IE had none of the above. A third plus-maze aquarium was used for spatial and object recognition tests. Different visual clues in 2 of its 4 arms were used to guide fish to reach the criteria to complete the task. The test consisted of 30 sessions and was concluded when each animal performed three consecutive correct choices or seven alternated, each ten trials. Learning rates revealed significant differences between EE and IE fish. The optical fractionator was used to estimate the total number of telencephalic cells that were stained with cresyl violet. On average, the total number of cells in the subjects from EE was higher than those from subjects maintained in IE (P=0.0202). We suggest that environmental enrichment significantly influenced goldfish spatial learning and memory abilities, and this may be associated with an increase in the total number of telencephalic cells.


Assuntos
Proliferação de Células/fisiologia , Peixes/fisiologia , Aprendizagem Espacial/fisiologia , Memória Espacial/fisiologia , Telencéfalo/metabolismo , Animais , Comportamento Animal/fisiologia , Contagem de Células , Feminino , Masculino , Condicionamento Físico Animal
8.
Psychopharmacology (Berl) ; 236(9): 2823-2834, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31115613

RESUMO

RATIONALE AND OBJECTIVE: Paeoniflorin has been reported to exhibit antidepressant-like effects in several animal model depression; and it also exerts a neuroprotective effect. In the present study, we investigated the effects of paeoniflorin administration on depression-like behaviors and cognitive abilities in mice subjected to chronic unpredictable mild stress (CUMS), an animal model associated with depressive disorders and cognitive deficits. METHODS: We administered paeoniflorin (20 mg/kg), which is the main active constituent extracted from Paeonia lactiflora Pall. and exerts multiple pharmacological actions, to CUMS mice. Subsequently, animals were subjected to tests of depression-like behavior including the sucrose preference test, the forced swimming test and the tail suspension test. The Morris water maze (MWM) task was applied to evaluate learning and memory capacity. Hippocampal CA1 long-term potentiation (LTP) was recorded. Dendritic spine density and the expression levels of brain-derived neurotrophic factor (BDNF) and postsynaptic density protein 95 (PSD95) in the hippocampus were also investigated. RESULTS: The administration of paeoniflorin protected against CUMS-induced depression-like behavior. Paeoniflorin also improved the performance of CUMS mice in the MWM. The impairment of hippocampal CA1 LTP caused by CUMS was also reversed. Furthermore, paeoniflorin administration prevented decreases in dendritic spine density and in the expression of BDNF and PSD95 in the hippocampus of CUMS mice. CONCLUSION: Our observations suggest that paeoniflorin is a potential antidepressant that protects against cognitive impairment in depression.


Assuntos
Glucosídeos/uso terapêutico , Hipocampo/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Monoterpenos/uso terapêutico , Aprendizagem Espacial/efeitos dos fármacos , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/psicologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/psicologia , Glucosídeos/farmacologia , Hipocampo/fisiopatologia , Potenciação de Longa Duração/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Monoterpenos/farmacologia , Técnicas de Cultura de Órgãos , Distribuição Aleatória , Aprendizagem Espacial/fisiologia , Estresse Psicológico/fisiopatologia
9.
eNeuro ; 6(1)2019.
Artigo em Inglês | MEDLINE | ID: mdl-30963102

RESUMO

Increased expression of the FK506-binding protein 5 (FKBP5) gene has been associated with a number of diseases, but most prominently in connection to psychiatric illnesses. Many of these psychiatric disorders present with dementia and other cognitive deficits, but a direct connection between these issues and alterations in FKBP5 remains unclear. We generated a novel transgenic mouse to selectively overexpress FKBP5, which encodes the FKBP51 protein, in the corticolimbic system, which had no overt effects on gross body weight, motor ability, or general anxiety. Instead, we found that overexpression of FKBP51 impaired long-term depression (LTD) as well as spatial reversal learning and memory, suggesting a role in glutamate receptor regulation. Indeed, FKBP51 altered the association of heat-shock protein 90 (Hsp90) with AMPA receptors, which was accompanied by an accelerated rate of AMPA recycling. In this way, the chaperone system is critical in triage decisions for AMPA receptor trafficking. Imbalance in the chaperone system may manifest in impairments in both inhibitory learning and cognitive function. These findings uncover an unexpected and essential mechanism for learning and memory that is controlled by the psychiatric risk factor FKBP5.


Assuntos
Cognição/fisiologia , Disfunção Cognitiva/metabolismo , Receptores de AMPA/metabolismo , Aprendizagem Espacial/fisiologia , Proteínas de Ligação a Tacrolimo/biossíntese , Animais , Disfunção Cognitiva/patologia , Feminino , Humanos , Depressão Sináptica de Longo Prazo/fisiologia , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Transgênicos , Transporte Proteico/fisiologia
10.
Nature ; 568(7752): 400-404, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30944479

RESUMO

The hippocampus and the medial entorhinal cortex are part of a brain system that maps self-location during navigation in the proximal environment1,2. In this system, correlations between neural firing and an animal's position or orientation are so evident that cell types have been given simple descriptive names, such as place cells3, grid cells4, border cells5,6 and head-direction cells7. While the number of identified functional cell types is growing at a steady rate, insights remain limited by an almost-exclusive reliance on recordings from rodents foraging in empty enclosures that are different from the richly populated, geometrically irregular environments of the natural world. In environments that contain discrete objects, animals are known to store information about distance and direction to those objects and to use this vector information to guide navigation8-10. Theoretical studies have proposed that such vector operations are supported by neurons that use distance and direction from discrete objects11,12 or boundaries13,14 to determine the animal's location, but-although some cells with vector-coding properties may be present in the hippocampus15 and subiculum16,17-it remains to be determined whether and how vectorial operations are implemented in the wider neural representation of space. Here we show that a large fraction of medial entorhinal cortex neurons fire specifically when mice are at given distances and directions from spatially confined objects. These 'object-vector cells' are tuned equally to a spectrum of discrete objects, irrespective of their location in the test arena, as well as to a broad range of dimensions and shapes, from point-like objects to extended surfaces. Our findings point to vector coding as a predominant form of position coding in the medial entorhinal cortex.


Assuntos
Córtex Entorrinal/fisiologia , Modelos Neurológicos , Percepção Espacial/fisiologia , Aprendizagem Espacial/fisiologia , Animais , Sinais (Psicologia) , Córtex Entorrinal/citologia , Hipocampo/citologia , Hipocampo/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/fisiologia
11.
Neuron ; 102(3): 683-693.e4, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-30871859

RESUMO

Little is known about the neural mechanisms that allow humans and animals to plan actions using knowledge of task contingencies. Emerging theories hypothesize that it involves the same hippocampal mechanisms that support self-localization and memory for locations. Yet limited direct evidence supports the link between planning and the hippocampal place map. We addressed this by investigating model-based planning and place memory in healthy controls and epilepsy patients treated using unilateral anterior temporal lobectomy with hippocampal resection. Both functions were impaired in the patient group. Specifically, the planning impairment was related to right hippocampal lesion size, controlling for overall lesion size. Furthermore, although planning and boundary-driven place memory covaried in the control group, this relationship was attenuated in patients, consistent with both functions relying on the same structure in the healthy brain. These findings clarify both the neural mechanism of model-based planning and the scope of hippocampal contributions to behavior.


Assuntos
Lobectomia Temporal Anterior , Epilepsia do Lobo Temporal/cirurgia , Hipocampo/cirurgia , Memória Espacial/fisiologia , Adulto , Estudos de Casos e Controles , Tomada de Decisões , Feminino , Hipocampo/diagnóstico por imagem , Hipocampo/fisiologia , Hipocampo/fisiopatologia , Humanos , Masculino , Aprendizagem Espacial/fisiologia , Análise e Desempenho de Tarefas
12.
Neural Plast ; 2019: 2158285, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30923551

RESUMO

Chronic cerebral hypoperfusion (CCH) is a common pathophysiological mechanism that underlies cognitive decline and degenerative processes in dementia and other neurodegenerative diseases. Low cerebral blood flow (CBF) during CCH leads to disturbances in the homeostasis of hemodynamics and energy metabolism, which in turn results in oxidative stress, astroglia overactivation, and synaptic protein downregulation. These events contribute to synaptic plasticity and cognitive dysfunction after CCH. Tripchlorolide (TRC) is an herbal compound with potent neuroprotective effects. The potential of TRC to improve CCH-induced cognitive impairment has not yet been determined. In the current study, we employed behavioral techniques, electrophysiology, Western blotting, immunofluorescence, and Golgi staining to investigate the effect of TRC on spatial learning and memory impairment and on synaptic plasticity changes in rats after CCH. Our findings showed that TRC could rescue CCH-induced spatial learning and memory dysfunction and improve long-term potentiation (LTP) disorders. We also found that TRC could prevent CCH-induced reductions in N-methyl-D-aspartic acid receptor 2B, synapsin I, and postsynaptic density protein 95 levels. Moreover, TRC upregulated cAMP-response element binding protein, which is an important transcription factor for synaptic proteins. TRC also prevented the reduction in dendritic spine density that is caused by CCH. However, sham rats treated with TRC did not show any improvement in cognition. Because CCH causes disturbances in brain energy homeostasis, TRC therapy may resolve this instability by correcting a variety of cognitive-related signaling pathways. However, for the normal brain, TRC treatment led to neither disturbance nor improvement in neural plasticity. Additionally, this treatment neither impaired nor further improved cognition. In conclusion, we found that TRC can improve spatial learning and memory, enhance synaptic plasticity, upregulate the expression of some synaptic proteins, and increase the density of dendritic spines. Our findings suggest that TRC may be beneficial in the treatment of cognitive impairment induced by CCH.


Assuntos
Isquemia Encefálica/complicações , Disfunção Cognitiva/tratamento farmacológico , Diterpenos/uso terapêutico , Plasticidade Neuronal/efeitos dos fármacos , Fenantrenos/uso terapêutico , Aprendizagem Espacial/efeitos dos fármacos , Animais , Isquemia Encefálica/psicologia , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/psicologia , Espinhas Dendríticas/efeitos dos fármacos , Espinhas Dendríticas/fisiologia , Diterpenos/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Masculino , Plasticidade Neuronal/fisiologia , Fenantrenos/farmacologia , Ratos , Ratos Sprague-Dawley , Aprendizagem Espacial/fisiologia
13.
Neuron ; 102(1): 217-231.e4, 2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30795901

RESUMO

Stable and efficient locomotion requires the precise coordination of movement across the limbs and body. Learned changes in interlimb coordination can be induced by exposure to a split-belt treadmill that imposes different speeds under each side of the body. Here, we demonstrate locomotor learning on a split-belt treadmill in mice. Mouse locomotor adaptation is specific to measures of interlimb coordination, has spatial and temporal components that adapt at different rates, and is context specific. The many similarities between human and mouse locomotor adaptation suggest that this form of locomotor learning is highly conserved across vertebrates. Using a variety of approaches, we demonstrate that split-belt adaptation in mice specifically depends on the intermediate cerebellum but is insensitive to large lesions of the cerebral cortex. Finally, cell-type-specific chemogenetics combined with quantitative behavioral analysis reveals that spatial and temporal components of locomotor adaptation are dissociable on the circuit level. VIDEO ABSTRACT.


Assuntos
Cerebelo/fisiologia , Marcha/fisiologia , Locomoção/fisiologia , Córtex Sensório-Motor/fisiologia , Aprendizagem Espacial/fisiologia , Adaptação Fisiológica , Animais , Ataxia/fisiopatologia , Córtex Cerebral/fisiologia , Análise da Marcha , Camundongos , Camundongos Endogâmicos , Camundongos Mutantes Neurológicos , Células de Purkinje/fisiologia , Fatores de Tempo
14.
eNeuro ; 6(1)2019.
Artigo em Inglês | MEDLINE | ID: mdl-30809587

RESUMO

The consolidation of newly formed memories and their retrieval are energetically demanding processes. Aerobic glycolysis (AG), also known as the Warburg effect, consists of the production of lactate from glucose in the presence of oxygen. The astrocyte neuron lactate shuttle hypothesis posits that astrocytes process glucose by AG to generate lactate, which is used as a fuel source within neurons to maintain synaptic activity. Studies in mice have demonstrated that lactate transport between astrocytes and neurons is required for long-term memory formation, yet the role of lactate production in memory acquisition and retrieval has not previously been explored. Here, we examined the effect of dichloroacetate (DCA), a chemical inhibitor of lactate production, on spatial learning and memory in mice using the Morris water maze (MWM). In vivo hyperpolarized 13C-pyruvate magnetic resonance spectroscopy revealed decreased conversion of pyruvate to lactate in the mouse brain following DCA administration, concomitant with a reduction in the phosphorylation of pyruvate dehydrogenase. DCA exposure before each training session in the MWM impaired learning, which subsequently resulted in impaired memory during the probe trial. In contrast, mice that underwent training without DCA exposure, but received a single DCA injection before the probe trial exhibited normal memory. Our findings indicate that AG plays a key role during memory acquisition but is less important for the retrieval of established memories. Thus, the activation of AG may be important for learning-dependent synaptic plasticity rather than the activation of signaling cascades required for memory retrieval.


Assuntos
Encéfalo/metabolismo , Glicólise , Rememoração Mental/fisiologia , Aprendizagem Espacial/fisiologia , Memória Espacial/fisiologia , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Fármacos do Sistema Nervoso Central/farmacologia , Ácido Dicloroacético/farmacologia , Glicólise/efeitos dos fármacos , Ácido Láctico/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Rememoração Mental/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Ácido Pirúvico/metabolismo , Aprendizagem Espacial/efeitos dos fármacos , Memória Espacial/efeitos dos fármacos
15.
Neuron ; 101(6): 1150-1165.e8, 2019 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-30713030

RESUMO

Diverse computations in the neocortex are aided by specialized GABAergic interneurons (INs), which selectively target other INs. However, much less is known about how these canonical disinhibitory circuit motifs contribute to network operations supporting spatial navigation and learning in the hippocampus. Using chronic two-photon calcium imaging in mice performing random foraging or goal-oriented learning tasks, we found that vasoactive intestinal polypeptide-expressing (VIP+), disinhibitory INs in hippocampal area CA1 form functional subpopulations defined by their modulation by behavioral states and task demands. Optogenetic manipulations of VIP+ INs and computational modeling further showed that VIP+ disinhibition is necessary for goal-directed learning and related reorganization of hippocampal pyramidal cell population dynamics. Our results demonstrate that disinhibitory circuits in the hippocampus play an active role in supporting spatial learning. VIDEO ABSTRACT.


Assuntos
Região CA1 Hipocampal/citologia , Interneurônios/fisiologia , Inibição Neural/fisiologia , Células Piramidais/fisiologia , Aprendizagem Espacial/fisiologia , Animais , Comportamento Apetitivo/fisiologia , Região CA1 Hipocampal/fisiologia , Metas , Hipocampo/citologia , Hipocampo/fisiologia , Interneurônios/citologia , Interneurônios/metabolismo , Camundongos , Neocórtex/citologia , Neocórtex/fisiologia , Optogenética , Células Piramidais/citologia , Peptídeo Intestinal Vasoativo/metabolismo
16.
Psychiatry Res ; 273: 528-536, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30710808

RESUMO

Brain-derived neurotrophic factor (BDNF) may be related to the pathophysiology of schizophrenia. This study aims to examine the relation between plasma BDNF levels and the cognition of patients with schizophrenia. We recruited 31 patients with chronic schizophrenia, 34 first-episode patients, and 35 healthy control subjects. We examined the MATRICS Consensus Cognitive Battery (MCCB) and the plasma BDNF levels in all groups. The schizophrenic symptoms were assessed using the positive and negative syndrome scale. The BDNF levels of schizophrenic patients were remarkably lower than those of the controls. The cognitive MCCB global composite scores and part index scores of schizophrenic patients were remarkably lower than those of the controls. Moreover, remarkable correlations were observed between BDNF levels and partial cognitive dimensions, such as visual learning, memory, and processing speed. Therefore, BDNF may be involved in the pathophysiology and cognitive impairment of schizophrenia.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/sangue , Disfunção Cognitiva/sangue , Disfunção Cognitiva/psicologia , Esquizofrenia/sangue , Psicologia do Esquizofrênico , Adolescente , Adulto , Biomarcadores/sangue , Doença Crônica , Disfunção Cognitiva/diagnóstico , Feminino , Humanos , Masculino , Memória/fisiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Esquizofrenia/diagnóstico , Aprendizagem Espacial/fisiologia , Adulto Jovem
17.
Neuroscience ; 404: 175-183, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30690136

RESUMO

Light has pervasive effects on the physiology and behavior of mammals. Several human studies have shown that light modulates cognitive functions; however, the mechanisms responsible for the effects of light remain unclear. Our previous work using diurnal male Nile grass rats (Arvicanthis niloticus) revealed that reduced illuminance during the day leads to impairments in hippocampal-dependent spatial learning/memory, reduced CA1 dendritic spine density, and attenuated hippocampal brain-derived neurotrophic factor (BDNF) expression in males. The present study examined the impact of ambient light intensity on hippocampal functions in female grass rats and explored sex differences in behavioral and hippocampal responses. Female grass rats were housed in either a 12:12-hr bright light-dark (brLD, 1000 lx) or dim light-dark (dimLD, 50 lx) cycle for four weeks. The dimLD group showed impaired spatial memory in the Morris water maze task and reduced CA1 apical dendritic spine density, similar to prior observations in males. However, the behavioral deficits seen in females were more severe than those seen in males, with dimLD females showing no evidence of long-term retention over the 24-hour periods between training sessions. In contrast to the attenuated hippocampal BDNF expression found in dimLD males, there was no significant difference in the expression of BDNF and of its receptor TrkB between females in brLD and dimLD. The results suggest that, as seen in male grass rats, reduced illuminance during the day impairs hippocampal-dependent spatial memory and hippocampal plasticity in female diurnal grass rats, but the underlying signaling pathways responsible for the effects of light restriction may differ between the sexes.


Assuntos
Hipocampo/fisiologia , Plasticidade Neuronal/fisiologia , Fotoperíodo , Aprendizagem Espacial/fisiologia , Memória Espacial/fisiologia , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Ritmo Circadiano/fisiologia , Cognição/fisiologia , Espinhas Dendríticas/metabolismo , Feminino , Hipocampo/metabolismo , Luz , Aprendizagem em Labirinto/fisiologia , Murinae , Receptor trkB/metabolismo
18.
Psychol Res ; 83(3): 476-484, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30613900

RESUMO

The present study tested whether the coupling of covert attentional shifts and motor planning of pointing movements can be modulated by learning. Participants performed two tasks. As a primary movement task, they executed a pointing movement to a movement target (MT) location. As a secondary visual attention task, they identified a discrimination target (DT) that was presented shortly before initiation of the pointing movement. These DTs either occurred at the same or at different locations with the MT. A common finding in such and similar settings is the enhanced visual target identification when locations of MT and DT coincide. However, it is not known which factors govern the flexibility of spatial attention-action coupling. Here, we tested the influence of previously learned spatial contingencies between MT and DT on the coupling of covert attention and motor planning. These contingencies were manipulated in three groups (always same locations, always opposite locations, non-contingent locations) in a training session. Results indicated that in a subsequent test phase, previously learned contingencies enhanced visual identification accordingly, even when targets for the movement task and the visual task were presented at opposite sides. These results corroborate previous findings of a rather flexible interaction of attention and motor planning, and demonstrate how one can learn to control attention by means of motor planning.


Assuntos
Atenção/fisiologia , Condicionamento Clássico/fisiologia , Movimento/fisiologia , Estimulação Luminosa/métodos , Aprendizagem Espacial/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
19.
Behav Brain Res ; 362: 173-180, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30659847

RESUMO

Spatial reference memory is known to be modulated by the dopaminergic system involving different brain regions. Here, we sought to identify the contribution of D1 (D1R) and D2 (D2R)-like dopamine receptor signaling on learning and memory in a food rewarded hole-board task by intracerebroventricular infusing D1R- and D2R- like receptor agonists (SKF-81297 and Sumanirole) and antagonists (SCH 23390 and Remoxipride) once 30 min prior to daily training sessions. D1R agonism induced persistent enhancement of performance, whereas D1R antagonism impaired reference memory formation. D2R agonist and antagonist exerted no effects. Phase specific comparisons revealed an enhancement of spatial acquisition in the presence of the D1R but not D2R agonism on acquisition, but not during retention. Since task difficulty might skew dopamine-induced improvements in learning and memory, we tested the D1R agonist in the hole-board task with increased difficulty. Drug treated animals performed significantly better during all training phases, with results better resolved than in the easy task. Additionally, proteomic analysis of the prefrontal cortex revealed ninety six proteins to be regulated by D1R agonism, from which 35 were correlated with behavioral performance. Obtained targets were grouped by function, showing synaptic transmission, synaptic remodeling, and dendritic spine morphology as the major functional classes affected. In sum, we find that activation of D1R signaling during spatial acquisition and retention improved reference memory index, depended on the task difficulty, and altered the proteome landscape of the prefrontal cortex indicative of massive organizational synaptic restructuring.


Assuntos
Receptores de Dopamina D1/agonistas , Receptores de Dopamina D2/agonistas , Aprendizagem Espacial/fisiologia , Memória Espacial/fisiologia , Animais , Benzazepinas/farmacologia , Espinhas Dendríticas/efeitos dos fármacos , Espinhas Dendríticas/metabolismo , Dopamina/metabolismo , Masculino , Ratos Sprague-Dawley , Receptores de Dopamina D1/fisiologia , Receptores de Dopamina D2/fisiologia , Transdução de Sinais/efeitos dos fármacos , Aprendizagem Espacial/efeitos dos fármacos , Memória Espacial/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia
20.
Neuroscience ; 401: 96-105, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30599271

RESUMO

Alzheimer's disease (AD) is characterized by the accumulation of amyloid-ß and tau proteins, which are believed to lead to neural damage that translates into brain dysfunction and cognitive deficits. Brain dysfunction can be evaluated by measuring single-neuron activity (spikes), global neural activity (local field potentials, LFPs) and the interaction between them. Considering that the dynamic interactions between the hippocampal pyramidal cells and lateral septum are important for proper structure function, we used the complete septo-hippocampal preparation from 30-day-old controls and J20-AD transgenic mice to record changes in spiking activity from the lateral septum and its relationship with LFP activity from the CA1 area. The cross-correlation analysis revealed that young J20 transgenic mice exhibit a significant reduction in coupling between lateral septum single-cell activity and neural network activity from the hippocampal CA1. Consistently, phase-lock analysis between lateral septum single-cell activity and CA1 neural network activity showed lower values in J20 transgenic mice. Similarly, the LFP- LFP coherence between CA1 and septum in the theta range showed lower values in J20 animals. Importantly, alterations were found before any detectable signs of cognitive deficits. Our data indicate that the disruption in the communication between hippocampus and rostral lateral septum is an early event in AD pathology and may contribute to the deficits observed during AD.


Assuntos
Doença de Alzheimer/fisiopatologia , Hipocampo/fisiopatologia , Rede Nervosa/fisiologia , Núcleos Septais/fisiologia , Doença de Alzheimer/patologia , Animais , Região CA1 Hipocampal/patologia , Região CA1 Hipocampal/fisiologia , Modelos Animais de Doenças , Hipocampo/patologia , Aprendizagem/fisiologia , Masculino , Camundongos , Camundongos Transgênicos , Rede Nervosa/patologia , Células Piramidais/fisiologia , Núcleos Septais/patologia , Aprendizagem Espacial/fisiologia , Lobo Temporal/patologia , Lobo Temporal/fisiologia , Ritmo Teta
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA