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1.
Int J Mol Sci ; 22(11)2021 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34204060

RESUMO

The establishment of neuronal circuits requires neurons to develop and maintain appropriate connections with cellular partners in and out the central nervous system. These phenomena include elaboration of dendritic arborization and formation of synaptic contacts, initially made in excess. Subsequently, refinement occurs, and pruning takes places both at axonal and synaptic level, defining a homeostatic balance maintained throughout the lifespan. All these events require genetic regulations which happens cell-autonomously and are strongly influenced by environmental factors. This review aims to discuss the involvement of guidance cues from the Semaphorin family.


Assuntos
Orientação de Axônios/fisiologia , Sinais (Psicologia) , Modelos Neurológicos , Neurônios/fisiologia , Semaforinas/metabolismo , Animais , Humanos , Plasticidade Neuronal/fisiologia
2.
J Acoust Soc Am ; 149(5): 3133, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34241105

RESUMO

For abruptly gated sound, interaural time difference (ITD) cues at onset carry greater perceptual weight than those following. This research explored how envelope shape influences such carrier ITD weighting. Experiment 1 assessed the perceived lateralization of a tonal binaural beat that transitioned through ITD (diotic envelope, mean carrier frequency of 500 Hz). Listeners' left/right lateralization judgments were compared to those for static-ITD tones. For an 8 Hz sinusoidally amplitude-modulated envelope, ITD cues 24 ms after onset well-predicted reported sidedness. For an equivalent-duration "abrupt" envelope, which was unmodulated besides 20-ms onset/offset ramps, reported sidedness corresponded to ITDs near onset (e.g., 6 ms). However, unlike for sinusoidal amplitude modulation, ITDs toward offset seemingly also influenced perceived sidedness. Experiment 2 adjusted the duration of the offset ramp (25-75 ms) and found evidence for such offset weighting only for the most abrupt ramp tested. In experiment 3, an ITD was imposed on a brief segment of otherwise diotic filtered noise. Listeners discriminated right- from left-leading ITDs. In sinusoidal amplitude modulation, thresholds were lowest when the ITD segment occurred during rising amplitude. For the abrupt envelope, the lowest thresholds were observed when the segment occurred at either onset or offset. These experiments demonstrate the influence of envelope profile on carrier ITD sensitivity.


Assuntos
Localização de Som , Estimulação Acústica , Sinais (Psicologia) , Ruído , Som
3.
Int J Mol Sci ; 22(13)2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34281244

RESUMO

Olfaction is an important neural system for survival and fundamental behaviors such as predator avoidance, food finding, memory formation, reproduction, and social communication. However, the neural circuits and pathways associated with the olfactory system in various behaviors are not fully understood. Recent advances in optogenetics, high-resolution in vivo imaging, and reconstructions of neuronal circuits have created new opportunities to understand such neural circuits. Here, we generated a transgenic zebrafish to manipulate olfactory signal optically, expressing the Channelrhodopsin (ChR2) under the control of the olfactory specific promoter, omp. We observed light-induced neuronal activity of olfactory system in the transgenic fish by examining c-fos expression, and a calcium indicator suggesting that blue light stimulation caused activation of olfactory neurons in a non-invasive manner. To examine whether the photo-activation of olfactory sensory neurons affect behavior of zebrafish larvae, we devised a behavioral choice paradigm and tested how zebrafish larvae choose between two conflicting sensory cues, an aversive odor or the naturally preferred phototaxis. We found that when the conflicting cues (the preferred light and aversive odor) were presented together simultaneously, zebrafish larvae swam away from the aversive odor. However, the transgenic fish with photo-activation were insensitive to the aversive odor and exhibited olfactory desensitization upon optical stimulation of ChR2. These results show that an aversive olfactory stimulus can override phototaxis, and that olfaction is important in decision making in zebrafish. This new transgenic model will be useful for the analysis of olfaction related behaviors and for the dissection of underlying neural circuits.


Assuntos
Channelrhodopsins/metabolismo , Percepção Olfatória/genética , Olfato/genética , Animais , Animais Geneticamente Modificados/genética , Channelrhodopsins/genética , Sinais (Psicologia) , Larva/fisiologia , Luz , Rede Nervosa/metabolismo , Neurônios/metabolismo , Odorantes , Optogenética/métodos , Estimulação Luminosa , Regiões Promotoras Genéticas/genética , Natação , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
4.
J Exp Biol ; 224(11)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34115116

RESUMO

Navigating across light gradients is essential for survival for many animals. However, we still have a poor understanding of the algorithms that underlie such behaviors. Here, we developed a novel closed-loop phototaxis assay for Drosophila larvae in which light intensity is always spatially uniform but updates depending on the location of the animal in the arena. Even though larvae can only rely on temporal cues during runs, we find that they are capable of finding preferred areas of low light intensity. Further detailed analysis of their behavior reveals that larvae turn more frequently and that heading angle changes increase when they experience brightness increments over extended periods of time. We suggest that temporal integration of brightness change during runs is an important - and so far largely unexplored - element of phototaxis.


Assuntos
Drosophila , Fototaxia , Animais , Comportamento Animal , Sinais (Psicologia) , Drosophila melanogaster , Larva , Luz
5.
J Exp Biol ; 224(11)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34115117

RESUMO

One persistent question in animal navigation is how animals follow habitual routes between their home and a food source. Our current understanding of insect navigation suggests an interplay between visual memories, collision avoidance and path integration, the continuous integration of distance and direction travelled. However, these behavioural modules have to be continuously updated with instantaneous visual information. In order to alleviate this need, the insect could learn and replicate habitual movements ('movement memories') around objects (e.g. a bent trajectory around an object) to reach its destination. We investigated whether bumblebees, Bombus terrestris, learn and use movement memories en route to their home. Using a novel experimental paradigm, we habituated bumblebees to establish a habitual route in a flight tunnel containing 'invisible' obstacles. We then confronted them with conflicting cues leading to different choice directions depending on whether they rely on movement or visual memories. The results suggest that they use movement memories to navigate, but also rely on visual memories to solve conflicting situations. We investigated whether the observed behaviour was due to other guidance systems, such as path integration or optic flow-based flight control, and found that neither of these systems was sufficient to explain the behaviour.


Assuntos
Voo Animal , Fluxo Óptico , Animais , Abelhas , Sinais (Psicologia) , Comportamento de Retorno ao Território Vital , Memória
6.
Res Dev Disabil ; 115: 104001, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34090086

RESUMO

BACKGROUND: The transition from primary to secondary school is particularly difficult for autistic children, a transition underpinned by an increase in prospective memory (PM) demands. AIMS: To better understand PM in autistic children of the relevant age range and its underlying processes, the current study investigated the impact of cue salience (distinctiveness) on PM in autistic and non-autistic children and adolescents. The study was unique in manipulating the visual and auditory salience of PM cues. Salient cues are assumed to put lower demands on executive control resources as compared to cues that blend in with the ongoing activity. METHODS AND PROCEDURES: The children completed a computer-based categorisation task in which an event-based PM task was embedded. The salience of PM cues was manipulated (low, high visual and high auditory salience). OUTCOMES AND RESULTS: Results revealed that both groups benefitted from an increase in visual and auditory salience, but only autistic participants were faster to respond to auditory cues. CONCLUSIONS AND IMPLICATIONS: Increased cue salience improved PM performance for all children. Positive effects of auditory cues were especially evident in autistic children.


Assuntos
Transtorno Autístico , Memória Episódica , Adolescente , Criança , Cognição , Sinais (Psicologia) , Função Executiva , Humanos
7.
ACS Nano ; 15(6): 9967-9986, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34081852

RESUMO

Metastasis is the primary reason for treatment failure and cancer-related deaths. Hence forecasting the disease in its primary state can advance the prognosis. However, existing techniques fail to reveal the tumor heterogeneity or its evolutionary cascades; hence they are not feasible to predict the onset of metastatic cancer. The key to metastasis originates from the primary tumor cells, evolving by inheriting multistep sequential cue signals. We have identified this specific population, termed metastatic cancer stem-like cells (MCSCs), to foresee cancer's ability to metastasize. An invasive property renders MCSCs nonadherent, summoning a powerful technique to forecast metastasis. Thus, we have generated an ultrasensitive 3D-metasensor to efficiently capture and investigate MCSCs and magnify the vital premetastatic signals from a single cell. We developed 3D-metasensor by an ultrafast laser ionization technique, consisting of self-assembled three-dimensionally organized nanoprobes incorporated with dopant functionalities. This distinct methodology establishes attachment with nonadherent MCSCs, elevates Raman activity, and enables probing of consequent signals (metabolic, proliferation, and metastatic) specifically altered in MCSCs. Extensive analysis using prediction tools-the area under the curve (AUC) and principal component analysis (PCA)-revealed high sensitivity (100%) and specificity (80%) to differentiate the MCSCs from other populations. Further, investigation reveals that the cue signal level from MCSCs of primary cancer is analogous to MCSCs from higher-level tumors, disclosing the relative dependence to estimate the primary tumor's capacity to metastasize. Multiple spectrum evaluation using the metasensor pinpoint the dynamic cues in MCSCs predict the onset of metastasis; thus, exploring these metastasis hallmarks can enhance prognosis and revolutionize therapy strategies.


Assuntos
Sinais (Psicologia) , Células-Tronco Neoplásicas , Linhagem Celular Tumoral , Humanos , Metástase Neoplásica/patologia , Células-Tronco Neoplásicas/patologia
8.
Transl Psychiatry ; 11(1): 355, 2021 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-34120149

RESUMO

Ibudilast, a neuroimmune modulator which selectively inhibits phosphodiesterases (PDE)-3, -4, -10, and -11, and macrophage migration inhibitory factor (MIF), shows promise as a novel pharmacotherapy for alcohol use disorder (AUD). However, the mechanisms of action underlying ibudilast's effects on the human brain remain largely unknown. Thus, the current study examined the efficacy of ibudilast to improve negative mood, reduce heavy drinking, and attenuate neural reward signals in individuals with AUD. Fifty-two nontreatment-seeking individuals with AUD were randomized to receive ibudilast (n = 24) or placebo (n = 28). Participants completed a 2-week daily diary study during which they filled out daily reports of their past day drinking, mood, and craving. Participants completed an functional magnetic resonance imaging (fMRI) alcohol cue-reactivity paradigm half-way through the study. Ibudilast did not have a significant effect on negative mood (ß = -0.34, p = 0.62). However, ibudilast, relative to placebo, reduced the odds of heavy drinking across time by 45% (OR = 0.55, (95% CI: 0.30, 0.98)). Ibudilast also attenuated alcohol cue-elicited activation in the ventral striatum (VS) compared to placebo (F(1,44) = 7.36, p = 0.01). Alcohol cue-elicited activation in the VS predicted subsequent drinking in the ibudilast group (F(1,44) = 6.39, p = 0.02), such that individuals who had attenuated ventral striatal activation and took ibudilast had the fewest number of drinks per drinking day in the week following the scan. These findings extend preclinical and human laboratory studies of the utility of ibudilast to treat AUD and suggest a biobehavioral mechanism through which ibudilast acts, namely, by reducing the rewarding response to alcohol cues in the brain leading to a reduction in heavy drinking.


Assuntos
Alcoolismo , Sinais (Psicologia) , Consumo de Bebidas Alcoólicas/tratamento farmacológico , Alcoolismo/tratamento farmacológico , Fissura , Humanos , Imageamento por Ressonância Magnética , Piridinas
9.
BMC Ecol Evol ; 21(1): 117, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112109

RESUMO

BACKGROUND: Tracing the association between insect cold tolerance and latitudinally and locally varying environmental conditions, as well as key morphological traits and molecular mechanisms, is essential for understanding the processes involved in adaptation. We explored these issues in two closely-related species, Drosophila montana and Drosophila flavomontana, originating from diverse climatic locations across several latitudes on the coastal and mountainous regions of North America. We also investigated the association between sequence variation in one of the key circadian clock genes, vrille, and cold tolerance in both species. Finally, we studied the impact of vrille on fly cold tolerance and cold acclimation ability by silencing it with RNA interference in D. montana. RESULTS: We performed a principal component analysis (PCA) on variables representing bioclimatic conditions on the study sites and used latitude as a proxy of photoperiod. PC1 separated the mountainous continental sites from the coastal ones based on temperature variability and precipitation, while PC2 arranged the sites based on summer and annual mean temperatures. Cold tolerance tests showed D. montana to be more cold-tolerant than D. flavomontana and chill coma resistance (CTmin) of this species showed an association with PC2. Chill coma recovery time (CCRT) of both species improved towards northern latitudes, and in D. flavomontana this trait was also associated with PC1. D. flavomontana flies were darkest in the coast and in the northern mountainous populations, but coloration showed no linkage with cold tolerance. Body size decreased towards cold environments in both species, but only within D. montana populations largest flies showed fastest recovery from cold. Finally, both the sequence analysis and RNAi study on vrille suggested this gene to play an essential role in D. montana cold resistance and acclimation, but not in recovery time. CONCLUSIONS: Our study demonstrates the complexity of insect cold tolerance and emphasizes the need to trace its association with multiple environmental variables and morphological traits to identify potential agents of natural selection. It also shows that a circadian clock gene vrille is essential both for short- and long-term cold acclimation, potentially elucidating the connection between circadian clock system and cold tolerance.


Assuntos
Relógios Circadianos , Animais , Relógios Circadianos/genética , Temperatura Baixa , Sinais (Psicologia) , Drosophila/genética , América do Norte
10.
Am J Alzheimers Dis Other Demen ; 36: 15333175211025911, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34151595

RESUMO

OBJECTIVE: To first validate the diagnostic accuracy of the "Triana Test," a new story recall test based on emotional material. METHOD: A phase I study of validation. We included 55 patients with amnestic Mild Cognitive Impairment and 69 healthy controls, diagnosed according to the "Memory Associative Test of the district of Seine-Saint-Denis" (TMA-93), and matched by age, gender, and educational level. The Triana Test's diagnostic accuracy was calculated by ROC curve analysis and Spearman correlations estimated its convergent validity with a hippocampal memory test, the Free and Cued Selective Reminding Test with Immediate Recall (FCSRT+IR). RESULTS: The "Triana Test" immediate and delayed recalls showed adequate diagnostic accuracy (AUC ≥ 0,74). The delayed free recall showed the highest diagnostic accuracy (AUC = 0.86). Correlations with the FCSRT+IR were moderate to strong. CONCLUSIONS: The "Triana Test" demonstrated accuracy for discriminating amnestic Mild Cognitive Impairment patients from healthy controls and convergent validity with the FCSRT+IR.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Disfunção Cognitiva/diagnóstico , Sinais (Psicologia) , Humanos , Rememoração Mental , Testes Neuropsicológicos
11.
Nat Commun ; 12(1): 3609, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34127675

RESUMO

The insulo-opercular network functions critically not only in encoding taste, but also in guiding behavior based on anticipated food availability. However, there remains no direct measurement of insulo-opercular activity when humans anticipate taste. Here, we collect direct, intracranial recordings during a food task that elicits anticipatory and consummatory taste responses, and during ad libitum consumption of meals. While cue-specific high-frequency broadband (70-170 Hz) activity predominant in the left posterior insula is selective for taste-neutral cues, sparse cue-specific regions in the anterior insula are selective for palatable cues. Latency analysis reveals this insular activity is preceded by non-discriminatory activity in the frontal operculum. During ad libitum meal consumption, time-locked high-frequency broadband activity at the time of food intake discriminates food types and is associated with cue-specific activity during the task. These findings reveal spatiotemporally-specific activity in the human insulo-opercular cortex that underlies anticipatory evaluation of food across both controlled and naturalistic settings.


Assuntos
Córtex Cerebral/fisiologia , Alimentos , Percepção Gustatória/fisiologia , Paladar/fisiologia , Adulto , Córtex Cerebral/diagnóstico por imagem , Sinais (Psicologia) , Eletroencefalografia , Fenômenos Eletrofisiológicos , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Acta Psychol (Amst) ; 218: 103352, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34144492

RESUMO

We examined selective directed forgetting in motor memory using a new variant of a three-list approach, to distinguish between accounts of directed forgetting. Participants consecutively studied three lists (L1, L2, and L3) of four sequential four-finger movements each. After studying L2, participants in the forget group were instructed to selectively forget the just studied four items of L2 but to retain the previously studied four items of L1, whereas the remember group did not receive any forget instruction for L2 but was encouraged to retain the items of both lists. In addition, we switched (switch groups) or repeated the items-enacting hand (no-switch groups) between L2 and L3 for a manipulation of post-forget-cue material competition for L2. A final memory test assessed recall performance for all three lists. Selective directed forgetting (lower L2 recall in the forget group as compared to the remember group) only occurred if the same hand was used for L2 and L3 (high interference between L2 and L3 encoding) whereas no selective directed forgetting occurred if the hand switched between L2 and L3 (low interference between L2 and L3 encoding). These results suggest that an inhibitory mechanism caused (selective) directed-forgetting costs that was triggered when items studied after the forget instruction had the potential to interfere with already stored items (i.e. were to be enacted by the same hand). When subsequently studied items pertained to the other hand no directed-forgetting costs occurred.


Assuntos
Memória , Rememoração Mental , Cognição , Sinais (Psicologia) , Dedos , Humanos , Movimento
13.
Oecologia ; 196(3): 667-677, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34173057

RESUMO

Chemical communication plays an important role in mammalian life history decisions. Animals send and receive information based on body odour secretions. Odour cues provide important social information on identity, kinship, sex, group membership or genetic quality. Recent findings show, that rodents alarm their conspecifics with danger-dependent body odours after encountering a predator. In this study, we aim to identify the chemistry of alarm pheromones (AP) in the bank vole, a common boreal rodent. Furthermore, the vole foraging efficiency under perceived fear was measured in a set of field experiments in large outdoor enclosures. During the analysis of bank vole odour by gas chromatography-mass spectrometry, we identified that 1-octanol, 2-octanone, and one unknown compound as the most likely candidates to function as alarm signals. These compounds were independent of the vole's sex. In a field experiment, voles were foraging less, i.e. they were more afraid in the AP odour foraging trays during the first day, as the odour was fresh, than in the second day. This verified the short lasting effect of volatile APs. Our results clarified the chemistry of alarming body odour compounds in mammals, and enhanced our understanding of the ecological role of AP and chemical communication in mammals.


Assuntos
Arvicolinae , Feromônios , Animais , Sinais (Psicologia) , Medo , Odorantes
14.
Biol Lett ; 17(6): 20210115, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34062087

RESUMO

Knowing where our limbs are in space is crucial for a successful interaction with the external world. Joint position sense (JPS) relies on both cues from muscle spindles and joint mechanoreceptors, as well as the effort required to move. However, JPS may also rely on the perceived external force on the limb, such as the gravitational field. It is well known that the internal model of gravity plays a large role in perception and behaviour. Thus, we have explored whether direct vestibular-gravitational cues could influence JPS. Participants passively estimated the position of their hand while they were upright and therefore aligned with terrestrial gravity, or pitch-tilted 45° backwards from gravity. Overall participants overestimated the position of their hand in both upright and tilted postures; however, the proprioceptive bias was significantly reduced when participants were tilted. Our findings therefore suggest that the internal model of gravity may influence and update JPS in order to allow the organism to interact with the environment.


Assuntos
Gravitação , Propriocepção , Sinais (Psicologia) , Humanos , Postura
15.
Biol Lett ; 17(6): 20210125, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34102069

RESUMO

While avoidance of sick conspecifics is common among animals, little is known about how detecting diseased conspecifics influences an organism's physiological state, despite its implications for disease transmission dynamics. The avian pathogen Mycoplasma gallisepticum (MG) causes obvious visual signs of infection in domestic canaries (Serinus canaria domestica), including lethargy and conjunctivitis, making this system a useful tool for investigating how the perception of cues from sick individuals shapes immunity in healthy individuals. We tested whether disease-related social information can stimulate immune responses in canaries housed in visual contact with either healthy or MG-infected conspecifics. We found higher complement activity and higher heterophil counts in healthy birds viewing MG-infected individuals around 6-12 days post-inoculation, which corresponded with the greatest degree of disease pathology in infected stimulus birds. However, we did not detect the effects of disease-related social cues on the expression of two proinflammatory cytokines in the blood. These data indicate that social cues of infection can alter immune responses in healthy individuals and suggest that public information about the disease can shape how individuals respond to infection.


Assuntos
Doenças das Aves , Infecções por Mycoplasma , Mycoplasma gallisepticum , Aves Canoras , Animais , Canários , Sinais (Psicologia) , Infecções por Mycoplasma/veterinária , Percepção
16.
Lab Chip ; 21(14): 2691-2701, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34165109

RESUMO

Cells in their native microenvironment are subjected to varying combinations of biochemical cues and mechanical cues in a wide range. Although many signaling pathways have been found to be responsive for extracellular cues, little is known about how biochemical cues crosstalk with mechanical cues in a complex microenvironment. Here, we introduced heterogeneous droplets on a microchip, which were rapidly assembled by combining wettability-patterned microchip and programmed droplet manipulations, for a high-throughput cell screening of the varying combinations of biochemical cues and mechanical cues. This platform constructed a heterogeneous droplet/microgel array with orthogonal gradual chemicals and materials, which was further applied to analyze the cellular Wnt/ß-catenin signaling in response to varying combinations of Wnt ligands and substrate stiffness. Thus, this device provides a powerful multiplexed bioassay platform for drug development, tissue engineering, and stem cell screening.


Assuntos
Sinais (Psicologia) , Ensaios de Triagem em Larga Escala , Transdução de Sinais , Células-Tronco , Engenharia Tecidual
17.
Acta Psychol (Amst) ; 218: 103347, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34082379

RESUMO

Magic tricks are deceiving, yet we can readily generate an explanation for a trick that we do not fully understand. In three experiments, we show that the way people explain a mental magic trick depends on their individual cognitive style. Analytical thinkers tend to generate explanations that appeal to rationality, such as using physical props to accomplish an effect. In contrast, intuitive thinkers are more likely to generate irrational explanations that accord with the magician's provided backstory, such as using subliminal cues to guide a spectator's choices. We observe this effect when measuring a participant's cognitive style using the Cognitive Reflection Test, and also when manipulating a participant's cognitive style using a simple narrative prompt.


Assuntos
Magia , Pensamento , Cognição , Sinais (Psicologia) , Humanos , Personalidade
18.
Behav Processes ; 189: 104439, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34087348

RESUMO

In the present study we analysed spatial learning in Vespula germanica wasps when dealing with a walking Y-maze. We recorded the time taken to leave the maze during two consecutive visits and which of the two short arms was chosen to exit. Two treatments were conducted to evaluate whether wasps learned to leave the Y-maze guided either by spatial or visual cues. In Treatment 1, the colour of both arms remained unchanged between two consecutive visits; and in Treatment 2, the position of the coloured arm was switched after the first trial. Our results demonstrated that the time taken to exit the maze on the second trial was less than half in both treatments and wasps left the maze from the previously chosen arm, irrespective of its colour. This is the first study to demonstrate spatial learning in V. germanica wasps by using a walking Y-maze. Free flying wasps learned to enter the Y-maze on their own volition, walk through it, collect food and find their way out more rapidly after a single foraging experience. The current experimental device is suitable for the evaluation of spatial memory processes and exploratory behaviour in this species.


Assuntos
Vespas , Animais , Bioensaio , Sinais (Psicologia) , Aprendizagem em Labirinto , Projetos Piloto , Memória Espacial
19.
Behav Processes ; 189: 104437, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34089779

RESUMO

Sexually dimorphic performance has been observed across humans and rodents in many spatial tasks. In general, these spatial tasks do not dissociate the use of environmental and self-movement cues. Previous work has demonstrated a role for self-movement cue processing in organizing open field behavior; however, these studies have not directly compared female and male movement characteristics. The current study examined the organization of open field behavior under dark conditions in female and male rats. Significant differences between female and male rats were observed in the location of stopping behavior relative to a cue and the topography exhibited during lateral movements. In contrast, no sex differences were observed on measures used to detect self-movement cue processing deficits. These results provide evidence that female and male rats are similar in their use of self-movement cues to organize open field behavior; however, other factors may be contributing to differences in performance.


Assuntos
Comportamento Exploratório , Comportamento Espacial , Animais , Sinais (Psicologia) , Feminino , Masculino , Orientação , Ratos , Ratos Long-Evans
20.
Sensors (Basel) ; 21(11)2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071729

RESUMO

Cochlear implants (CIs) recover hearing in severely to profoundly hearing-impaired people by electrically stimulating the cochlea. While they are extremely effective, spatial hearing is typically severely limited. Recent studies have shown that haptic stimulation can supplement the electrical CI signal (electro-haptic stimulation) and substantially improve sound localization. In haptic sound-localization studies, the signal is extracted from the audio received by behind-the-ear devices and delivered to each wrist. Localization is achieved using tactile intensity differences (TIDs) across the wrists, which match sound intensity differences across the ears (a key sound localization cue). The current study established sensitivity to across-limb TIDs at three candidate locations for a wearable haptic device, namely: the lower tricep and the palmar and dorsal wrist. At all locations, TID sensitivity was similar to the sensitivity to across-ear intensity differences for normal-hearing listeners. This suggests that greater haptic sound-localization accuracy than previously shown can be achieved. The dynamic range was also measured and far exceeded that available through electrical CI stimulation for all of the locations, suggesting that haptic stimulation could provide additional sound-intensity information. These results indicate that an effective haptic aid could be deployed for any of the candidate locations, and could offer a low-cost, non-invasive means of improving outcomes for hearing-impaired listeners.


Assuntos
Implante Coclear , Implantes Cocleares , Localização de Som , Percepção da Fala , Estimulação Acústica , Sinais (Psicologia) , Humanos
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