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1.
Proc Natl Acad Sci U S A ; 117(29): 17288-17295, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32632013

RESUMO

Big brown bats transmit wideband FM biosonar sounds that sweep from 55 to 25 kHz (first harmonic, FM1) and from 110 to 50 kHz (second harmonic, FM2). FM1 is required to perceive echo delay for target ranging; FM2 contributes only if corresponding FM1 frequencies are present. We show that echoes need only the lowest FM1 broadcast frequencies of 25 to 30 kHz for delay perception. If these frequencies are removed, no delay is perceived. Bats begin echo processing at the lowest frequencies and accumulate perceptual acuity over successively higher frequencies, but they cannot proceed without the low-frequency starting point in their broadcasts. This reveals a solution to pulse-echo ambiguity, a serious problem for radar or sonar. In dense, extended biosonar scenes, bats have to emit sounds rapidly to avoid collisions with near objects. But if a new broadcast is emitted when echoes of the previous broadcast still are arriving, echoes from both broadcasts intermingle, creating ambiguity about which echo corresponds to which broadcast. Frequency hopping by several kilohertz from one broadcast to the next can segregate overlapping narrowband echo streams, but wideband FM echoes ordinarily do not segregate because their spectra still overlap. By starting echo processing at the lowest frequencies in frequency-hopped broadcasts, echoes of the higher hopped broadcast are prevented from being accepted by lower hopped broadcasts, and ambiguity is avoided. The bat-inspired spectrogram correlation and transformation (SCAT) model also begins at the lowest frequencies; echoes that lack them are eliminated from processing of delay and no longer cause ambiguity.


Assuntos
Quirópteros/fisiologia , Ecolocação/fisiologia , Som , Animais , Percepção Auditiva/fisiologia , Percepção Espacial/fisiologia , Fatores de Tempo , Ondas Ultrassônicas , Ultrassom
2.
PLoS One ; 15(7): e0235964, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32697771

RESUMO

Simon tasks reveal implicit processing conflicts that arise when the abstract coding of stimulus position is incongruent with coding for location of the output response. Participants were tested with two versions of a Simon task in a counterbalanced order to examine a potential female bias for attending to object characteristics versus object location. Both tasks used a triangle pointing to the left or right. A simple version presented the triangle in an inner or outer position relative to central fixation. A more complex version included a frame surrounding the inner-outer triangle presentation area in order to introduce additional visual elements for left/right visual processing. When the No Frame version was the first presented, there were no sex differences in the Simon effect in either version, which is consistent with results from other studies that did not provide feedback regarding accuracy. When the initial test was the Frame version, we observed a reverse Simon effect for incongruent triangles presented in the left inner position, with females faster than males to identify the incongruent condition versus the congruent (-59 vs -5 msec). In the No Frame condition that followed, females showed a carryover effect from the previous Frame condition, exhibiting positive Simon effects that were two fold larger than males for identifying incongruent stimuli presented in the left and right outer positions. Similar to previous Simon studies, females showed longer overall reaction times than males (~15%). The difference was not related to the Simon effect and is also found in other types of tasks involving early visual processing of objects with location. Based on sex differences in the Simon effect that emerged following initial experience of the triangle adjoining the frame, the present results support a female bias toward broader integration of objects within the context of location.


Assuntos
Comportamento de Escolha/fisiologia , Cognição/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Percepção Espacial/fisiologia , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa , Fatores Sexuais , Adulto Jovem
3.
Int J Neural Syst ; 30(6): 2050026, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32498642

RESUMO

Brain-computer interfaces (BCIs) can provide a means of communication to individuals with severe motor disorders, such as those presenting as locked-in. Many BCI paradigms rely on motor neural pathways, which are often impaired in these individuals. However, recent findings suggest that visuospatial function may remain intact. This study aimed to determine whether visuospatial imagery, a previously unexplored task, could be used to signify intent in an online electroencephalography (EEG)-based BCI. Eighteen typically developed participants imagined checkerboard arrow stimuli in four quadrants of the visual field in 5-s trials, while signals were collected using 16 dry electrodes over the visual cortex. In online blocks, participants received graded visual feedback based on their performance. An initial BCI pipeline (visuospatial imagery classifier I) attained a mean accuracy of [Formula: see text]% classifying rest against visuospatial imagery in online trials. This BCI pipeline was further improved using restriction to alpha band features (visuospatial imagery classifier II), resulting in a mean pseudo-online accuracy of [Formula: see text]%. Accuracies exceeded the threshold for practical BCIs in 12 participants. This study supports the use of visuospatial imagery as a real-time, binary EEG-BCI control paradigm.


Assuntos
Interfaces Cérebro-Computador , Eletroencefalografia , Retroalimentação Sensorial/fisiologia , Imaginação/fisiologia , Intenção , Reconhecimento Visual de Modelos/fisiologia , Percepção Espacial/fisiologia , Córtex Visual/fisiologia , Adulto , Ritmo alfa/fisiologia , Humanos
4.
J Vis ; 20(6): 17, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32579672

RESUMO

Prior knowledge can help observers in various situations. Adults can simultaneously learn two location priors and integrate these with sensory information to locate hidden objects. Importantly, observers weight prior and sensory (likelihood) information differently depending on their respective reliabilities, in line with principles of Bayesian inference. Yet, there is limited evidence that observers actually perform Bayesian inference, rather than a heuristic, such as forming a look-up table. To distinguish these possibilities, we ask whether previously learned priors will be immediately integrated with a new, untrained likelihood. If observers use Bayesian principles, they should immediately put less weight on the new, less reliable, likelihood ("Bayesian transfer"). In an initial experiment, observers estimated the position of a hidden target, drawn from one of two distinct distributions, using sensory and prior information. The sensory cue consisted of dots drawn from a Gaussian distribution centered on the true location with either low, medium, or high variance; the latter introduced after block three of five to test for evidence of Bayesian transfer. Observers did not weight the cue (relative to the prior) significantly less in the high compared to medium variance condition, counter to Bayesian predictions. However, when explicitly informed of the different prior variabilities, observers placed less weight on the new high variance likelihood ("Bayesian transfer"), yet, substantially diverged from ideal. Much of this divergence can be captured by a model that weights sensory information, according only to internal noise in using the cue. These results emphasize the limits of Bayesian models in complex tasks.


Assuntos
Teorema de Bayes , Percepção de Forma/fisiologia , Percepção Espacial/fisiologia , Adolescente , Adulto , Feminino , Heurística , Humanos , Aprendizagem , Masculino , Distribuição Normal , Probabilidade , Adulto Jovem
5.
Nat Neurosci ; 23(8): 1004-1015, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32541964

RESUMO

Neurons represent spatial information in diverse reference frames, but it remains unclear whether neural reference frames change with task demands and whether these changes can account for behavior. In this study, we examined how neurons represent the direction of a moving object during self-motion, while monkeys switched, from trial to trial, between reporting object direction in head- and world-centered reference frames. Self-motion information is needed to compute object motion in world coordinates but should be ignored when judging object motion in head coordinates. Neural responses in the ventral intraparietal area are modulated by the task reference frame, such that population activity represents object direction in either reference frame. In contrast, responses in the lateral portion of the medial superior temporal area primarily represent object motion in head coordinates. Our findings demonstrate a neural representation of object motion that changes with task requirements.


Assuntos
Potenciais de Ação/fisiologia , Percepção de Movimento/fisiologia , Neurônios/fisiologia , Lobo Parietal/fisiologia , Animais , Macaca mulatta , Masculino , Estimulação Luminosa , Percepção Espacial/fisiologia
6.
PLoS One ; 15(6): e0233544, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32479531

RESUMO

Recently, Wang and Theeuwes used the additional singleton task and showed that attentional capture was reduced for the location that was likely to contain a distractor [1]. It is argued that due to statistical learning, the location that was likely to contain a distractor was suppressed relative to all other locations. The current study replicated these findings and by adding a search-probe condition, we were able to determine the initial distribution of attentional resources across the visual field. Consistent with a space-based resource allocation ("biased competition") model, it was shown that the representation of a probe presented at the location that was likely to contain a distractor was suppressed relative to other locations. Critically, the suppression of this location resulted in more attention being allocated to the target location relative to a condition in which the distractor was not suppressed. This suggests that less capture by the distractor results in more attention being allocated to the target. The results are consistent with the view that the location that is likely to contain a distractor is suppressed before display onset, modulating the first feed-forward sweep of information input into the spatial priority map.


Assuntos
Atenção/fisiologia , Aprendizagem/fisiologia , Percepção Espacial/fisiologia , Adolescente , Sinais (Psicologia) , Feminino , Humanos , Inibição Psicológica , Masculino , Probabilidade , Tempo de Reação/fisiologia , Percepção Visual/fisiologia , Adulto Jovem
7.
Br J Anaesth ; 125(2): 168-174, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32560911

RESUMO

BACKGROUND: The effect of mental rotation training on ultrasound-guided regional anaesthesia (UGRA) skill acquisition is currently unknown. In this study we aimed to examine whether mental rotation skill training can improve UGRA task performance by novice operators. METHODS: We enrolled 94 volunteers with no prior experience of UGRA in this randomised controlled study. After a baseline mental rotation test, their performance in a standardised UGRA needling task was independently assessed by two raters using the composite error score (CES) and global rating scale (GRS). Volunteers with low baseline mental rotation ability were randomised to a mental rotation training group or a no training group, and the UGRA needling task was repeated to determine the impact of the training intervention on task performance. The study primary outcome measure was UGRA needling task CES measured before and after the training intervention. RESULTS: Multivariate analyses controlling for age, gender, and previous performance showed that participants exposed to the training intervention made significantly fewer errors (CES B=-0.66 [standard error, se=0.17]; P<0.001; 95% confidence interval [CI], -0.92 to -0.26) and displayed improved overall performance (GRS B=6.15 [se=2.99], P=0.048, 95% CI=0.06 to 12.13) when undertaking the UGRA needling task. CONCLUSIONS: A simple training intervention, based on the manipulation and rotation of three-dimensional models, results in improved technical performance of a UGRA needling task in operators with low baseline mental rotation skills.


Assuntos
Anestesia por Condução/métodos , Anestesiologia/educação , Competência Clínica/estatística & dados numéricos , Percepção Espacial/fisiologia , Ultrassonografia de Intervenção/métodos , Percepção Visual/fisiologia , Adulto , Educação de Pós-Graduação em Medicina , Feminino , Humanos , Masculino , Estudos Prospectivos , Adulto Jovem
8.
Nature ; 583(7814): 103-108, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32494012

RESUMO

The inferotemporal (IT) cortex is responsible for object recognition, but it is unclear how the representation of visual objects is organized in this part of the brain. Areas that are selective for categories such as faces, bodies, and scenes have been found1-5, but large parts of IT cortex lack any known specialization, raising the question of what general principle governs IT organization. Here we used functional MRI, microstimulation, electrophysiology, and deep networks to investigate the organization of macaque IT cortex. We built a low-dimensional object space to describe general objects using a feedforward deep neural network trained on object classification6. Responses of IT cells to a large set of objects revealed that single IT cells project incoming objects onto specific axes of this space. Anatomically, cells were clustered into four networks according to the first two components of their preferred axes, forming a map of object space. This map was repeated across three hierarchical stages of increasing view invariance, and cells that comprised these maps collectively harboured sufficient coding capacity to approximately reconstruct objects. These results provide a unified picture of IT organization in which category-selective regions are part of a coarse map of object space whose dimensions can be extracted from a deep network.


Assuntos
Modelos Neurológicos , Percepção Espacial/fisiologia , Lobo Temporal/citologia , Lobo Temporal/fisiologia , Animais , Estimulação Elétrica , Macaca mulatta/fisiologia , Imagem por Ressonância Magnética , Masculino , Vias Neurais/fisiologia , Lobo Temporal/anatomia & histologia
9.
Sci Rep ; 10(1): 7205, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32350337

RESUMO

In birds, like in mammals, the hippocampus is particularly sensitive to exposure to novel environments, a function that is based on visual input. Chicks' eyes are placed laterally and their optic fibers project mainly to the contralateral brain hemispheres, with only little direct interhemispheric coupling. Thus, monocular occlusion has been frequently used in chicks to document functional specialization of the two hemispheres. However, we do not know whether monocular occlusion influences hippocampal activation. The aim of the present work was to fill this gap by directly testing this hypothesis. To induce hippocampal activation, chicks were exposed to a novel environment with their left or right eye occluded, or in conditions of binocular vision. Their hippocampal expression of c-Fos (neural activity marker) was compared to a baseline group that remained in a familiar environment. Interestingly, while the hippocampal activation in the two monocular groups was not different from the baseline, it was significantly higher in the binocular group exposed to the novel environment. This suggest that the representation of environmental novelty in the hippocampus of domestic chicks involves strong binocular integration.


Assuntos
Proteínas Aviárias/metabolismo , Hipocampo/fisiologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Percepção Espacial/fisiologia , Visão Monocular/fisiologia , Animais , Galinhas , Visão Binocular/fisiologia
10.
PLoS One ; 15(4): e0231959, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32352993

RESUMO

We measured psychophysical thresholds for discriminating the speeds of two arrays of moving dots. The arrays could be juxtaposed or could be spatially separated by up to 10 degrees of visual angle, eccentricity being held constant. We found that the precision of the judgments varied little with separation. Moreover, the function relating threshold to separation was similar whether the arrays moved in the same, in opposite or in orthogonal directions. And there was no significant difference in threshold whether the two stimuli were initially presented to the same cerebral hemisphere or to opposite ones. How are human observers able to compare stimuli that fall at well separated positions in the visual field? We consider two classes of explanation: (i) Observers' judgments might be based directly on the signals of dedicated 'comparator neurons', i.e. neurons drawing inputs of opposite sign from local regions of the visual field. (ii) Signals about local features might be transmitted to the site of comparison by a shared 'cerebral bus', where the same physical substrate carries different information from moment to moment. The minimal effects of proximity and direction (which might be expected to influence local detectors of relative motion), and the combinatorial explosion in the number of comparator neurons that would be required by (i), lead us to favor models of type (ii).


Assuntos
Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Humanos , Percepção de Movimento/fisiologia , Psicofísica , Fatores de Tempo
11.
J Vis Exp ; (158)2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32420980

RESUMO

Vestibular disorders are among the most common syndromes in medicine. In recent years, new vestibular diagnostic systems have been introduced that allow the examination of all semicircular canals in the clinical setting. Assessment methods of the otolithic system, which is responsible for the perception of linear acceleration and perception of gravity, are far less in clinical use. There are several experimental approaches for measuring the perception of gravity. The most frequently used method is the determination of the subjective visual vertical. This is usually measured with the head in an upright position. We present here an assessment method for testing otolith function in the roll plane. The subjective visual vertical is measured in the head upright position as well as with head inclination of ± 15° and ± 30° in the roll plane. This extended functional paradigm is an easy-to-perform clinical test of otolith function and ensures increased information content for the detection of impaired graviceptive perception.


Assuntos
Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Gravitação , Humanos , Masculino , Pessoa de Meia-Idade
12.
Neuron ; 107(2): 338-350.e5, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32428433

RESUMO

Across sensory areas, neural microcircuits consolidate streams of information into unified representations of the external world. In the carnivore visual cortex, where eye-specific inputs first converge, it has been posited that a single, binocularly aligned modular orientation representation develops independent of sensory experience. In this study of ferret visual cortex using in vivo calcium imaging, we find evidence for a different developmental process. Early in development, contralateral, ipsilateral, or binocular stimulation each yield well-organized modular representations of orientation that display features of mature cortex. However, comparison of these representations reveals considerable misalignment that is evident at both modular and cellular scales. Experience-dependent processes drive reorganization of these three representations toward a single binocularly aligned representation resembling the early binocular representation through shifts in cellular orientation preference. Thus, while orderly modular networks of orientation preference initially arise independent of visual experience, experience is critical for the alignment of these early representations.


Assuntos
Córtex Cerebral/fisiologia , Furões/fisiologia , Orientação Espacial/fisiologia , Percepção Espacial/fisiologia , Visão Binocular/fisiologia , Animais , Rede Nervosa/fisiologia , Estimulação Luminosa , Privação Sensorial , Córtex Visual/fisiologia , Vias Visuais/fisiologia
13.
PLoS Comput Biol ; 16(5): e1007489, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32379824

RESUMO

Path integration is thought to rely on vestibular and proprioceptive cues yet most studies in humans involve primarily visual input, providing limited insight into their respective contributions. We developed a paradigm involving walking in an omnidirectional treadmill in which participants were guided on two sides of a triangle and then found their back way to origin. In Experiment 1, we tested a range of different triangle types while keeping the distance of the unguided side constant to determine the influence of spatial geometry. Participants overshot the angle they needed to turn and undershot the distance they needed to walk, with no consistent effect of triangle type. In Experiment 2, we manipulated distance while keeping angle constant to determine how path integration operated over both shorter and longer distances. Participants underestimated the distance they needed to walk to the origin, with error increasing as a function of the walked distance. To attempt to account for our findings, we developed configural-based computational models involving vector addition, the second of which included terms for the influence of past trials on the current one. We compared against a previously developed configural model of human path integration, the Encoding-Error model. We found that the vector addition models captured the tendency of participants to under-encode guided sides of the triangles and an influence of past trials on current trials. Together, our findings expand our understanding of body-based contributions to human path integration, further suggesting the value of vector addition models in understanding these important components of human navigation.


Assuntos
Orientação/fisiologia , Percepção Espacial/fisiologia , Navegação Espacial/fisiologia , Adulto , Biologia Computacional/métodos , Sinais (Psicologia) , Feminino , Humanos , Masculino , Modelos Teóricos , Propriocepção/fisiologia , Caminhada/fisiologia
14.
Sci Rep ; 10(1): 6735, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32317714

RESUMO

Recently, cortical correlates of specific dream contents have been reported, such as the activation of the sensorimotor cortex during dreamed hand clenching. Yet, despite a close resemblance of such activation patterns to those seen during the corresponding wakeful behaviour, the causal mechanisms underlying specific dream contents remain largely elusive. Here, we aimed to investigate the causal role of the sensorimotor cortex in generating movement and bodily sensations during REM sleep dreaming. Following bihemispheric transcranial direct current stimulation (tDCS) or sham stimulation, guided by functional mapping of the primary motor cortex, naive participants were awakened from REM sleep and responded to a questionnaire on bodily sensations in dreams. Electromyographic (EMG) and electroencephalographic (EEG) recordings were used to quantify physiological changes during the preceding REM period. We found that tDCS, compared to sham stimulation, significantly decreased reports of dream movement, especially of repetitive actions. Other types of bodily experiences, such as tactile or vestibular sensations, were not affected by tDCS, confirming the specificity of stimulation effects to movement sensations. In addition, tDCS reduced EEG interhemispheric coherence in parietal areas and affected the phasic EMG correlation between both arms. These findings show that a complex temporal reorganization of the motor network co-occurred with the reduction of dream movement, revealing a link between central and peripheral motor processes and movement sensations of the dream self. tDCS over the sensorimotor cortex interferes with dream movement during REM sleep, which is consistent with a causal contribution to dream experience and has broader implications for understanding the neural basis of self-experience in dreams.


Assuntos
Sonhos/fisiologia , Cinestesia/fisiologia , Rememoração Mental/fisiologia , Córtex Sensório-Motor/fisiologia , Sono REM/fisiologia , Adulto , Sonhos/psicologia , Eletroencefalografia , Feminino , Humanos , Masculino , Polissonografia , Percepção Espacial/fisiologia , Técnicas Estereotáxicas , Inquéritos e Questionários , Percepção do Tato/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Vigília/fisiologia
15.
Sci Rep ; 10(1): 5687, 2020 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-32231235

RESUMO

The sensorimotor system sets up plastic alterations to face new demands. Terms such as adaptation and learning are broadly used to describe a variety of processes underlying this aptitude. The mechanisms whereby transformations acquired to face a perturbation generalize to other situations or stay context-dependent remain weakly understood. Here, we compared the performance of hand pointing vs throwing to visual targets while facing an optical shift of the visual field (prismatic deviation). We found that the transfer of compensations was conditioned by the task performed during exposure to the perturbation: compensations transferred from pointing to throwing but not at all from throwing to pointing. Additionally, expertise on the task performed during exposure had a marked influence on the amount of transfer to the non-exposed task: throwing experts (dart players) remarkably transferred compensations to the pointing task. Our results reveal that different processes underlying these distinct transfer properties may be at work to face a given perturbation. Their solicitation depends on mastery for the exposed task, which is responsible for different patterns of inter-task transfer. An important implication is that transfer properties, and not only after-effects, should be included as a criterion for adaptation. At the theoretical level, we suggest that tasks may need to be mastered before they can be subjected to adaptation, which has new implications for the distinction between learning and adaptation.


Assuntos
Retroalimentação Sensorial/fisiologia , Desempenho Psicomotor/fisiologia , Percepção Visual/fisiologia , Aclimatação/fisiologia , Adaptação Fisiológica/fisiologia , Adulto , Feminino , Mãos/fisiologia , Humanos , Masculino , Atividade Motora/fisiologia , Estimulação Luminosa/métodos , Córtex Sensório-Motor/fisiologia , Percepção Espacial/fisiologia , Campos Visuais/fisiologia , Adulto Jovem
16.
J Neurosci ; 40(21): 4172-4184, 2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32300047

RESUMO

The nucleus isthmi pars magnocellularis (Imc), a group of inhibitory neurons in the midbrain tegmentum, is a critical component of the spatial selection network in the vertebrate midbrain. It delivers long-range inhibition among different portions of the space map in the optic tectum (OT), thereby mediating stimulus competition in the OT. Here, we investigate the properties of relative strength-dependent competitive interactions within the Imc, in barn owls of both sexes. We find that when Imc neurons are presented simultaneously with one stimulus inside the receptive field and a second, competing stimulus outside, they exhibit gradual or switch-like response profiles as a function of relative stimulus strength. They do so both when the two stimuli are of the same sensory modality (both visual) or of different sensory modalities (visual and auditory). Moreover, Imc neurons signal the strongest stimulus in a dynamically flexible manner, indicating that Imc responses reflect an online comparison between the strengths of the competing stimuli. Notably, Imc neurons signal the strongest stimulus more categorically, and earlier than the OT. Paired recordings at spatially aligned sites in the Imc and OT reveal that although some properties of stimulus competition, such as the bias of competitive response profiles, are correlated, others such as the steepness of response profiles, are set independently. Our results demonstrate that the Imc is itself an active site of competition, and may be the first site in the midbrain selection network at which stimulus competition is resolved.SIGNIFICANCE STATEMENT This work sheds light on the functional properties of a small group of inhibitory neurons in the vertebrate midbrain that play a key part in how the brain selects a target among competitors. A better understanding of the functioning of these neurons is an important building block for the broader understanding of how distracters are suppressed, and of spatial attention and its dysfunction.


Assuntos
Atenção/fisiologia , Percepção Auditiva/fisiologia , Inibição Neural/fisiologia , Neurônios/fisiologia , Tegmento Mesencefálico/fisiologia , Percepção Visual/fisiologia , Estimulação Acústica , Animais , Feminino , Masculino , Estimulação Luminosa , Percepção Espacial/fisiologia , Estrigiformes
17.
J Exp Psychol Hum Percept Perform ; 46(4): 388-404, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32223291

RESUMO

Researchers propose 2 opposing views regarding visuospatial attentional distributions of tool space. Tool-use in far space either (a) remaps peripersonal space leading to distributed attention along the tool, or (b) shifts attention to the tool's functional end. However, most studies employ only one type of functional tool action to support their view. This study assessed whether attentional distributions are explained by different tool action types performed in space relative to the body. In Experiment 1, participants used a curved tool to push objects in far space or pull objects from far-to-near space, n = 96. Visual attention (mean correct RT, d') was measured at three equidistant target locations (tool handle, middle shaft, functional end) in far space, before and after tool actions using a 50/50, go/no-go target discrimination task. In Experiment 2, push actions were confined to near space and pull actions to far space, n = 96. Regardless of pushing or pulling, tool actions in far space improved attention only at the tool's end. Pulling objects into near space distributed attentional facilitation along the tool's length. Thus, tool-use peripersonal space remapping and attentional shifts may be dependent on specific functional tool actions in near and far space. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Atenção/fisiologia , Desempenho Psicomotor/fisiologia , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Espaço Pessoal , Adulto Jovem
18.
J Exp Psychol Hum Percept Perform ; 46(4): 416-433, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32223293

RESUMO

A typical way to investigate the relationship between spatial attention and the programming of an eye movement is with a dual-task. Here, participants simultaneously make an eye movement in 1 direction and discriminate a target at the same or a different location. Results of these tasks consistently find that performance is best at the goal of an upcoming eye movement. It is less clear, however, the extent to which spatial attention can shift independently of the programmed saccade. In this article, for the first time, we use an evidence accumulation model to examine this longstanding question. Specifically, across 2 studies, we quantify the relative contributions of spatial attention and saccade preparation in a perceptual dual-task. Our results establish that there is a unique and measurable effect of spatial attention away from the saccade goal, and, interestingly, that the relative magnitude of this effect varies by cue type. There is a larger influence of spatial attention when a peripheral rather than a central cue is employed. We suggest that these results support the claim that each form of orienting is mediated by a distinct underlying mechanism. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Atenção/fisiologia , Desempenho Psicomotor/fisiologia , Movimentos Sacádicos/fisiologia , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Medições dos Movimentos Oculares , Feminino , Humanos , Masculino , Adulto Jovem
19.
PLoS One ; 15(4): e0232128, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32324834

RESUMO

The social interactions that we experience from early infancy often involve actions that are not strictly instrumental but engage the recipient by eliciting a (complementary) response. Interactive gestures may have privileged access to our perceptual and motor systems either because of their intrinsically engaging nature or as a result of extensive social learning. We compared these two hypotheses in a series of behavioral experiments by presenting individuals with interactive gestures that call for motor responses to complement the interaction ('hand shaking', 'requesting', 'high-five') and with communicative gestures that are equally socially relevant and salient, but do not strictly require a response from the recipient ('Ok', 'Thumbs up', 'Peace'). By means of a spatial compatibility task, we measured the interfering power of these task-irrelevant stimuli on the behavioral responses of individuals asked to respond to a target. Across three experiments, our results showed that the interactive gestures impact on response selection and reduce spatial compatibility effects as compared to the communicative (non-interactive) gestures. Importantly, this effect was independent of the activation of specific social scripts that may interfere with response selection. Overall, our results show that interactive gestures have privileged access to our perceptual and motor systems, possibly because they entail an automatic preparation to respond that involuntary engages the motor system of the observers. We discuss the implications from a developmental and neurophysiological point of view.


Assuntos
Gestos , Relações Interpessoais , Desempenho Psicomotor/fisiologia , Adulto , Feminino , Lateralidade Funcional , Humanos , Masculino , Percepção de Movimento , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Adulto Jovem
20.
Nat Commun ; 11(1): 1986, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32332741

RESUMO

Visuospatial selective attention has been investigated primarily in head-fixed animals and almost exclusively in primates. Here, we develop two human-inspired, discrimination-based behavioral paradigms for studying selective visuospatial attention in freely behaving mice. In the 'spatial probability' task, we find enhanced accuracy, sensitivity, and rate of evidence accumulation at the location with higher probability of target occurrence, and opposite effects at the lower probability location. Together with video-based 3D head-tracking, these results demonstrate endogenous expectation-driven shifts of spatial attention. In the 'flanker' task, we find that a second stimulus presented with the target, but with conflicting information, causes switch-like decrements in accuracy and sensitivity as a function of its contrast, and slower evidence accumulation, demonstrating exogenous capture of spatial attention. The ability to study primate-like selective attention rigorously in unrestrained mice opens a rich avenue for research into neural circuit mechanisms underlying this critical executive function in a naturalistic setting.


Assuntos
Atenção/fisiologia , Função Executiva/fisiologia , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Animais , Técnicas de Observação do Comportamento , Comportamento Animal , Sinais (Psicologia) , Masculino , Camundongos , Modelos Animais
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