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1.
PLoS One ; 15(2): e0229343, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32106238

RESUMO

The visual system optimizes its functioning for a given environment through processes collectively called adaptation. It is currently unknown, however, whether adaptation is affected by the particular task the observer performs within that environment. Two experiments tested whether this is the case. Observers adapted to high contrast grating patterns, and the decay of adaptation was measured using a version of the tilt-aftereffect, while they performed two different secondary tasks. One task involved judging the luminance of a small circular spot at fixation, and was expected to be unaffected by adaptation. The other secondary task involved judging a low contrast grating, and adaptation was expected to make this task difficult by reducing the visibility of the grating. Identical displays containing both a fixation spot and a grating were used for both tasks. Tilt-aftereffects were smaller when subjects concurrently performed the grating task than when they performed the fixation task. These results suggest that the control of adaptation, in this case its decay, is sensitive to the nature of the task the observer is performing. Adaptation may attempt to optimize vision with respect to many different criteria simultaneously; task is likely one of the criteria included in this process.


Assuntos
Adaptação Ocular/fisiologia , Adaptação Fisiológica , Pós-Efeito de Figura/fisiologia , Reconhecimento Visual de Modelos , Análise e Desempenho de Tarefas , Percepção Visual/fisiologia , Adulto , Humanos , Adulto Jovem
2.
Psychol Res ; 84(4): 866-880, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30406829

RESUMO

The human nervous system displays such plasticity that we can adapt our motor behavior to various changes in environmental or body properties. However, how sensorimotor adaptation generalizes to new situations and new effectors, and which factors influence the underlying mechanisms, remains unclear. Here we tested the general hypothesis that differences across participants can be exploited to uncover what drives interlimb transfer. Twenty healthy adults adapted to prismatic glasses while reaching to visual targets with their dominant arm. Classic adaptation and generalization across movement directions were observed but transfer to the non-dominant arm was not significant and inter-individual differences were substantial. Interlimb transfer resulted for some participants in a directional shift of non-dominant arm movements that was consistent with an encoding of visuomotor adaptation in extrinsic coordinates. For some other participants, transfer was consistent with an intrinsic coordinate system. Simple and multiple regression analyses showed that a few kinematic parameters such as peak acceleration (or peak velocity) and variability of movement direction were correlated with interlimb transfer. Low peak acceleration and low variability were related to extrinsic transfer, while high peak acceleration and high variability were related to intrinsic transfer. Motor variability was also positively correlated with the magnitude of the after-effect systematically observed on the dominant arm. Overall, these findings on unconstrained movements support the idea that individual movement features could be linked to the sensorimotor adaptation and its generalization. The study also suggests that distinct movement characteristics may be related to different coordinate frames of action representations in the nervous system.


Assuntos
Adaptação Fisiológica/fisiologia , Pós-Efeito de Figura/fisiologia , Movimento/fisiologia , Transferência de Experiência/fisiologia , Fenômenos Biomecânicos/fisiologia , Feminino , Humanos , Individualidade , Masculino , Desempenho Psicomotor/fisiologia , Adulto Jovem
3.
Vision Res ; 162: 35-42, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31325461

RESUMO

Prolonged exposure to an emotional face biases our judgement of subsequent face stimulus toward the opposite emotion. This emotion aftereffect has been suggested to occur as early as 35 ms exposure duration in cartoon faces. In the current study, we are interested in investigating the time-course of brief emotional face adaptation, and the relationship between brief emotional face adaptation and prolonged emotional face adaptation. We adapted the subjects from 17 ms to 1000 ms with a happy or angry adapting face. We found that a facial emotion adaptation aftereffect started from 17 ms adapting duration for angry face adaptation, and from 50 ms for happy face adaptation. Factor analysis on the adaptation effects highlighted three different components: brief angry adaptation (17 ms, 34 ms, and 50 ms), prolonged angry adaptation (100 ms and 1000 ms), and happy face adaptation (from 17 ms to 1000 ms). We found that the brief angry face adaptation was negatively associated with the awareness of the adapting face, and the prolonged angry face adaptation was stronger in subjects who perceived the angry adapting face as more negative in valence. Together, these findings suggest that (1) facial emotion adaptation can be induced by brief (17 ms) adapting face presentation; (2) brief angry face adaptation may be related to early visual processing, whereas prolonged angry face adaptation may be related to adaptation at later and higher-level visual emotional processing; and (3) brief and prolonged adaptations may adapt different neural populations. Our findings thus shed light on the current understanding of the neural mechanisms of emotional face adaptation.


Assuntos
Adaptação Fisiológica/fisiologia , Ira , Emoções/fisiologia , Expressão Facial , Pós-Efeito de Figura/fisiologia , Felicidade , Feminino , Humanos , Masculino , Reconhecimento Visual de Modelos , Percepção Visual , Adulto Jovem
4.
PLoS One ; 14(5): e0217074, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31125360

RESUMO

Previous studies have shown that the size of the leftward bias after exposure to rightward prism-deviation (the prismatic after-effect) depends on the degree of rightward prism-deviation as well as the type of visual feedback receives during exposure to prism-deviation. In this study, we tested if it was possible to obtain a leftward bias in pointing precision using two different methods of creating diverted visual input by simulating a rightward prism diversion of visual input in immersive virtual reality. We compared the results to the leftward bias in pointing precision obtained after exposure to standard prism goggles deviating visual input 10 degrees to the right. Twenty healthy participants were subjected to one session of standard prism adaptation therapy under three different conditions of deviated visual input: 1) created by imitating a 10 degree leftward rotation of the head (VRR), 2) created by imitating a 2D leftward horizontal displacement of 10 degrees (VRS) and 3) a control condition using real right-deviating prisms (PCP). The study showed that the simulated prisms in the VRR and VRS conditions produced deviations in pointing precision of a similar size. However, exposure to the VRS and VRR conditions both produced larger prismatic after-effects than the exposure to real prism goggles. This research is important for the development and use of virtual reality systems in the rehabilitation of neglect after brain injury as it emphasizes that the adjustment to deviated visual input may be affected positively by the use of immersive virtual reality technology.


Assuntos
Adaptação Fisiológica/fisiologia , Pós-Efeito de Figura/fisiologia , Lateralidade Funcional/fisiologia , Desempenho Psicomotor/fisiologia , Percepção Espacial/fisiologia , Realidade Virtual , Percepção Visual/fisiologia , Adulto , Feminino , Voluntários Saudáveis , Humanos , Lentes , Masculino , Estimulação Luminosa
5.
Perception ; 48(4): 286-315, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30885042

RESUMO

Glass patterns (GPs) consist of randomly distributed dot pairs (dipoles) whose orientations are determined by specific geometric transforms. We investigated the role of visuospatial attention in the processing of global form from GPs by measuring the effect of distraction on adaptation to GPs. In the nondistracted condition, observers were adapted to coherent GPs. After the adaptation period, they were presented with a test GP divided in two halves along the vertical and were required to judge which side of the test GP was more coherent. In the attention-distracted condition, a high-load rapid serial visual presentation task was performed during the adapting period. The magnitude of the form after-effect was measured using a technique that measures the coherence level at which the test GP appears random. The rationale was that if attention has a modulatory effect on the spatial summation of dipoles, in the attention-distracted condition, we should expect a weaker form after-effect. However, the results showed stronger form after-effect in the attention-distracted condition than in the nondistracted condition, suggesting that distraction during adaptation increases the strength of form adaptation. Additional experiments suggested that distraction may reduce the spatial suppression from large-scale textures, strengthening the spatial summation of local-oriented signals.


Assuntos
Atenção/fisiologia , Pós-Efeito de Figura/fisiologia , Percepção de Forma/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Adulto , Humanos , Adulto Jovem
6.
Vision Res ; 158: 126-134, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30797766

RESUMO

The tilt aftereffect (TAE) occurs when, after adapting to an oriented line, a vertical line appears to be tilted in the opposite direction. The magnitude of the TAE has been shown to relate to the salience of the adapting stimulus (e.g., its contrast) as well as to the similarity between the adapting and testing stimuli. However, the relationship between TAE and orientation uncertainty - variability in the perceived orientation of the stimulus - of either the adapting or the testing stimulus and, more importantly, change in orientation uncertainty as a function of adaptation have not previously been explored. We manipulated stimulus salience by using a variety of contour types, including real and illusory contours. Tilt aftereffects were observed even for stimuli that had much weaker or invisible illusory contours. Orientation uncertainty of the adapting stimulus, as measured by the slope of a psychometric function in orientation discrimination, was positively correlated with TAE magnitude for real and illusory contours, but not for stimuli with weak contour percepts. On an individual subject level, orientation uncertainty increased post-adaptation and was correlated with pre-adaptation uncertainty. That is, individuals with more variability in their perception of orientation before adaptation showed increased variability in orientation discrimination following adaptation. This may account for some of the variability in TAE across individuals and stimulus types and is consistent with previous findings on increased orientation discrimination thresholds post-adaptation for nearby orientations.


Assuntos
Pós-Efeito de Figura/fisiologia , Percepção de Forma/fisiologia , Orientação Espacial/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Incerteza , Adaptação Ocular/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Córtex Visual/fisiologia , Adulto Jovem
7.
Cortex ; 111: 256-273, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30530268

RESUMO

We present a meta-analysis of the effects of visuomotor adaptation to leftward displacing prisms on visuospatial judgements in healthy people, as assessed by perceptual (landmark) and manual versions of the line bisection task. To supplement previously published datasets, we report two novel experiments: Experiment 1 (n = 12) found null effects of adaptation to 10° leftward prisms on spatial bias in the landmark task, and Experiment 2 (n = 24) found null effects of 12° leftward prisms on spatial bias in a computerised line bisection task. Including these data, we considered 17 experiments for the landmark task (total n = 256), and 12 experiments for line bisection (total n = 172), in which participants were adapted for between 7 and 20 min to prism strengths from 8 to 17°. A random-effects meta-analysis, with prism strength and exposure duration as moderators, confirmed robust rightward shifts in visuospatial judgements following leftward prism adaptation. The average standardised effect sizes (Cohen's d) were similar between tasks, increasing by around .1 per degree of prismatic displacement, and being boosted by a long (10 min +) period of prism exposure. However, the quality of evidence and precision of prediction was superior for the landmark task, with a higher signal-to-noise ratio within studies, and less heterogeneity between studies. We suggest that line bisection responses may be contaminated by sensorimotor aftereffects, and that the landmark task is a more suitable method for measuring true visuospatial aftereffects of prism adaptation. To harness these effects, we recommend that researchers should expose participants to 15° (or higher) leftward prisms for more than ten minutes, with upwards of 250 pointing movements. Power calculations should take account of heterogeneity in the true effect size between studies; and further investigation of the factors underlying this heterogeneity will help to refine optimally-effective methods.


Assuntos
Adaptação Fisiológica/fisiologia , Pós-Efeito de Figura/fisiologia , Lateralidade Funcional/fisiologia , Campos Visuais/fisiologia , Percepção Visual/fisiologia , Humanos , Julgamento , Estimulação Luminosa
8.
J Vis ; 18(12): 2, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30458510

RESUMO

After adapting to a certain motion direction, our perception of a similar direction will be repelled away from the adapting direction, a phenomenon known as the direction aftereffect (DAE). As the motion system consists of local and global processing stages, it remains unclear how the adaptation of the two stages contributes in producing the DAE. The present study addresses this question by independently inducing adaptation at local and global motion-processing levels. Local adaptation was manipulated by presenting test stimuli at either adapted or nonadapted locations. Global adaptation was manipulated by embedding one or five global motion directions in the adapting motion. Repulsive DAE, when measured using a multiple-element test pattern, was stronger when it was produced by global adaptation than when produced by local adaptation. Specifically, the DAE resulting from local adaptation (a) decreased when test orientations differed from adapting orientation, (b) decreased when local directions were disambiguated using plaid stimuli, (c) remained the same even when attention was focused at specific test locations during adaptation, and (d) increased when tested with a single element. Overall, these findings suggest that the strength of repulsive DAE depends on both the motion-processing level at which adaptation occurs and the level at which the DAE was tested. Furthermore, the repulsive DAE arising from local adaptation alone can be explained by the propagation of local speed repulsion instead of local direction repulsion. Findings are discussed in the context of how motion aftereffects arise from the adaptation of a hierarchical motion system.


Assuntos
Adaptação Ocular/fisiologia , Pós-Efeito de Figura/fisiologia , Percepção de Movimento/fisiologia , Viés , Humanos , Orientação , Estimulação Luminosa , Psicometria
9.
J Vis ; 18(9): 12, 2018 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-30208431

RESUMO

It is well known that prolonged observation of a high-contrast stimulus alters the perception of a subsequent test stimulus. Previous studies of perceived contrast shifts only reported perceived contrast reductions. Here, we used successive presentations of test and reference stimuli and found that perceived contrast was reduced if tests had a lower contrast than adaptors but was significantly enhanced when tests had a higher contrast than adaptors. Such bidirectional contrast aftereffects were not observed for single adaptor flashes but became increasingly pronounced for repeated adaptor presentations, thereby suggesting that the aftereffect is a consequence of adaptation rather than of attentional cuing or temporal repulsion. In addition, perceived contrast reduction weakened as we increasingly jittered the spatial position of the adaptor, but perceived contrast enhancement was observed for large spatial range of jittered adaptor positions. We conclude that aftereffects involve adaptation in distinct mechanisms with narrow and broad spatial tunings. Results suggest that the visual system not only possesses low-level contrast encoding units, which monotonically increase their responses as physical contrast increases, but is also equipped with high-level channels selectively tuned for particular contrast ranges.


Assuntos
Adaptação Fisiológica/fisiologia , Atenção/fisiologia , Sensibilidades de Contraste/fisiologia , Pós-Efeito de Figura/fisiologia , Análise de Variância , Sinais (Psicologia) , Humanos
10.
J Exp Psychol Hum Percept Perform ; 44(10): 1619-1628, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30058821

RESUMO

Prismatic adaptation (PA) results from repeated ballistic movements of the dominant arm toward visual targets while wearing prisms shifting the visual field laterally (visuomotor prismatic training [VPT]). Following PA, subjects' pointing movements are deviated contralaterally to prismatic shift (aftereffect). The question of whether spatial attention is also biased in the same direction remains controversial in the scientific literature. To investigate the effect of PA on spatial attention, we asked healthy participants to perform a visual detection threshold task before and after VPT with left- and right-deviating prisms and visuomotor training without prisms. Our results demonstrate that both left and right VPTs modulate visual detection threshold, significantly ameliorating detection accuracy and response times bilaterally. These data indicate that PA modulates visual attention bilaterally and that detection threshold paradigms are sensitive to its effects in the visual domain. We suggest that the described PA effects are mediated by the joint action of attentional and alerting mechanisms. (PsycINFO Database Record (c) 2018 APA, all rights reserved).


Assuntos
Adaptação Fisiológica/fisiologia , Atenção/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Detecção de Sinal Psicológico/fisiologia , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Pós-Efeito de Figura/fisiologia , Humanos , Masculino , Adulto Jovem
11.
Vision Res ; 149: 40-46, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29913245

RESUMO

Adaptation to changes of the environment is an essential function of the visual system. Recent studies have revealed that prolonged viewing of a point-light display of a human walker can produce the perception of a point-light walker facing in the opposite direction in a subsequent ambiguous test. Similar effects of biological motion adaptation have been documented for various properties of the point-light walkers. However, the time course and controlling mechanisms for biological motion adaptation have not yet been examined. The present study investigated whether a single mechanism or multiple mechanisms controlled biological motion adaptation. In Experiment 1, a relatively long duration of initial adaptation to one facing direction of a point-light walker was followed by a relatively short duration of deadaptation in which the adapter was a point-light walker of the opposite facing direction. Chimeric ambiguous walkers were used to test the aftereffect in a top-up manner. We observed spontaneous recovery of the adaptation effects in the post-test period. The Experiment 2 further delineated the build-up and decay of biological motion adaptation that accorded well with the duration scaling law (i.e., effects of adaptation become stronger and longer-lasting as adaptation duration increases). Further analysis indicated that the slower but not the faster component of the adaptation effects complied with the law. These findings suggest that biological motion adaptation is controlled by the multiple mechanisms tuned to differing timescales.


Assuntos
Adaptação Fisiológica/fisiologia , Pós-Efeito de Figura/fisiologia , Percepção de Movimento/fisiologia , Adulto , Análise de Variância , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Adulto Jovem
12.
Psychol Sci ; 29(6): 926-935, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29634402

RESUMO

Can what we imagine in our minds change how we perceive the world in the future? A continuous process of multisensory integration and recalibration is responsible for maintaining a correspondence between the senses (e.g., vision, touch, audition) and, ultimately, a stable and coherent perception of our environment. This process depends on the plasticity of our sensory systems. The so-called ventriloquism aftereffect-a shift in the perceived localization of sounds presented alone after repeated exposure to spatially mismatched auditory and visual stimuli-is a clear example of this type of plasticity in the audiovisual domain. In a series of six studies with 24 participants each, we investigated an imagery-induced ventriloquism aftereffect in which imagining a visual stimulus elicits the same frequency-specific auditory aftereffect as actually seeing one. These results demonstrate that mental imagery can recalibrate the senses and induce the same cross-modal sensory plasticity as real sensory stimuli.


Assuntos
Percepção Auditiva/fisiologia , Pós-Efeito de Figura/fisiologia , Imaginação/fisiologia , Plasticidade Neuronal/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
13.
Psychon Bull Rev ; 25(3): 1035-1042, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28616858

RESUMO

Perception of a facial expression can be altered or biased by a prolonged viewing of other facial expressions, known as the facial expression adaptation aftereffect (FEAA). Recent studies using antiexpressions have demonstrated a monotonic relation between the magnitude of the FEAA and adaptor extremity, suggesting that facial expressions are opponent coded and represented continuously from one expression to its antiexpression. However, it is unclear whether the opponent-coding scheme can account for the FEAA between two facial expressions. In the current study, we demonstrated that the magnitude of the FEAA between two facial expressions increased monotonically as a function of the intensity of adapting facial expressions, consistent with the predictions based on the opponent-coding model. Further, the monotonic increase in the FEAA occurred even when the intensity of an adapting face was too weak for its expression to be recognized. These results together suggest that multiple facial expressions are encoded and represented by balanced activity of neural populations tuned to different facial expressions.


Assuntos
Adaptação Fisiológica/fisiologia , Emoções/fisiologia , Expressão Facial , Reconhecimento Facial/fisiologia , Pós-Efeito de Figura/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
14.
J Exp Psychol Hum Percept Perform ; 44(2): 243-260, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28557489

RESUMO

Face identity can be represented in a multidimensional space centered on the average. It has been argued that the average acts as a perceptual norm, with the norm coded implicitly by balanced activation in pairs of channels that respond to opposite extremes of face dimensions (two-channel model). In Experiment 1 we used face identity aftereffects to distinguish this model from a narrow-band multichannel model with no norm. We show that as adaptors become more extreme, aftereffects initially increase sharply and then plateau. Crucially there is no decrease, ruling out narrow-band multichannel coding, but consistent with a two-channel norm-based model. However, these results leave open the possibility that there may be a third channel, tuned explicitly to the norm (three-channel model). In Experiment 2 we show that alternating adaptation widens the range identified as the average whereas adaptation to the average narrows the range, consistent with the three-channel model. Explicit modeling confirmed the three-channel model as the best fit for the combined data from both experiments. However, a two-channel model with decision criteria allowed to vary between adapting conditions, also provided a very good fit. These results support opponent, norm-based coding of face identity with additional explicit coding of the norm. (PsycINFO Database Record


Assuntos
Adaptação Fisiológica/fisiologia , Reconhecimento Facial/fisiologia , Pós-Efeito de Figura/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
15.
J Exp Psychol Hum Percept Perform ; 44(4): 503-517, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28825500

RESUMO

There are large, reliable individual differences in the recognition of facial expressions of emotion across the general population. The sources of this variation are not yet known. We investigated the contribution of a key face perception mechanism, adaptive coding, which calibrates perception to optimize discrimination within the current perceptual "diet." We expected that a facial expression system that readily recalibrates might boost sensitivity to variation among facial expressions, thereby enhancing recognition ability. We measured adaptive coding strength with an established facial expression aftereffect task and measured facial expression recognition ability with 3 tasks optimized for the assessment of individual differences. As expected, expression recognition ability was positively associated with the strength of facial expression aftereffects. We also asked whether individual variation in affective factors might contribute to expression recognition ability, given that clinical levels of such traits have previously been linked to ability. Expression recognition ability was negatively associated with self-reported anxiety but not with depression, mood, or degree of autism-like or empathetic traits. Finally, we showed that the perceptual factor of adaptive coding contributes to variation in expression recognition ability independently of affective factors. (PsycINFO Database Record


Assuntos
Emoções/fisiologia , Expressão Facial , Reconhecimento Facial/fisiologia , Percepção Social , Adolescente , Adulto , Feminino , Pós-Efeito de Figura/fisiologia , Humanos , Individualidade , Masculino , Adulto Jovem
16.
J Exp Psychol Hum Percept Perform ; 44(2): 176-194, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28504523

RESUMO

To accomplish effective motor control, the brain contains an internal forward model that predicts the expected sensory consequence of a motor command. When this prediction is inaccurate, a sensory prediction error is produced which adapts the forward model to make more accurate predictions of future movements. Other types of errors, such as task performance errors or reward, play less of a role in adapting a forward model. This raises the following question: What unique information is conveyed by the sensory prediction error that results in forward model adaptation? sensory prediction errors typically contain both the magnitude and direction of the error, but it is unclear if both components are necessary for adaptation or a single component is sufficient. In this article, we address this by having participants learn to counter a visuomotor rotation, which induces an angular mismatch between movements of the hand and visual feedback. We manipulated the information content of the visual feedback, in the form of a line, which accurately represented only the magnitude (distance), direction, or both magnitude and direction, of the virtual cursor relative to the target. We demonstrate that sensorimotor adaptation does not occur, or is minimal, when feedback is limited to information about the magnitude of an error. In contrast, sensorimotor adaptation is present when feedback is limited only to the direction of an error or when it contains combined direction and magnitude information. This result stands in contrast to current computational models of cerebellar-based sensorimotor adaptation that use error magnitude to drive adaptation. (PsycINFO Database Record


Assuntos
Adaptação Psicológica/fisiologia , Retroalimentação Sensorial/fisiologia , Pós-Efeito de Figura/fisiologia , Aprendizagem/fisiologia , Atividade Motora/fisiologia , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
17.
Acta Psychol (Amst) ; 184: 85-99, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28477841

RESUMO

In a prospective memory task, verbal instructions are used to define an appropriate target event as retrieval cue. This target event is typically part of an ongoing activity and is thus bivalent as it involves features relevant for both the prospective memory task and the ongoing task. Task switching research has demonstrated that responding to bivalent stimuli is costly and can slow down even subsequent performance. Thus, responding to prospective memory targets may also result in after-effects, expressed as slowed subsequent ongoing task performance. So far, ongoing task slowing has been mainly considered as a measure of strategic monitoring for the prospective memory cues. The purpose of this study was to investigate whether after-effects of responding to prospective memory targets contribute to this slowing. In four experiments, a prospective memory task was embedded in a task-switching paradigm and we manipulated the degree of task-set overlap between the prospective memory task and the ongoing task. The results showed consistent after-effects of responding to prospective memory targets in each experiment. Increasing task-set overlap increased the amount and longevity of the after-effects. Surprisingly, prospective memory retrieval was not accompanied by strategic monitoring. Thus, this study demonstrates that ongoing task slowing can occur in the absence of monitoring costs.


Assuntos
Cognição/fisiologia , Função Executiva/fisiologia , Pós-Efeito de Figura/fisiologia , Intenção , Memória Episódica , Desempenho Psicomotor/fisiologia , Adulto , Sinais (Psicologia) , Feminino , Humanos , Masculino , Tempo de Reação , Análise e Desempenho de Tarefas , Adulto Jovem
18.
J Exp Psychol Hum Percept Perform ; 44(5): 797-805, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29154633

RESUMO

Selective attention refers to the ability to selectively act upon relevant information at the expense of irrelevant information. Yet, in many experimental tasks, what happens to the representation of the irrelevant information is still debated. Typically, 2 approaches to distractor processing have been suggested, namely distractor inhibition and distractor-based retrieval. However, it is also typical that both processes are hard to disentangle. For instance, in the negative priming literature (for a review Frings, Schneider, & Fox, 2015) this has been a continuous debate since the early 1980s. In the present study, we attempted to prove that both processes exist, but that they reflect distractor processing at different levels of representation. Distractor inhibition impacts stimulus representation, whereas distractor-based retrieval impacts mainly motor processes. We investigated both processes in a distractor-priming task, which enables an independent measurement of both processes. For our argument that both processes impact different levels of distractor representation, we estimated the exponential parameter (τ) and Gaussian components (µ, σ) of the exponential Gaussian reaction-time (RT) distribution, which have previously been used to independently test the effects of cognitive and motor processes (e.g., Moutsopoulou & Waszak, 2012). The distractor-based retrieval effect was evident for the Gaussian component, which is typically discussed as reflecting motor processes, but not for the exponential parameter, whereas the inhibition component was evident for the exponential parameter, which is typically discussed as reflecting cognitive processes, but not for the Gaussian parameter. (PsycINFO Database Record


Assuntos
Atenção/fisiologia , Percepção de Cores/fisiologia , Pós-Efeito de Figura/fisiologia , Inibição Psicológica , Rememoração Mental/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
19.
Exp Brain Res ; 235(10): 3193-3206, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28755239

RESUMO

Damage to the temporal-parietal cortex in the right hemisphere often leads to spatial neglect-a disorder in which patients are unable to attend to sensory input from their contralesional (left) side. Neglect has been associated with both attentional and premotor deficits. That is, in addition to having difficulty with attending to the left side, patients are often slower to initiate leftward vs. rightward movements (i.e., directional hypokinesia). Previous research has indicated that a brief period of adaptation to rightward shifting prisms can reduce symptoms of neglect by adjusting the patient's movements leftward, toward the neglected field. Although prism adaptation has been shown to reduce spatial attention deficits in patients with neglect, very little work has examined the effects of prisms on premotor symptoms. In the current study, we examined this in healthy individuals using leftward shifting prisms to induce a rightward shift in the egocentric reference frame, similar to neglect patients prior to prism adaptation. Specifically, we examined the speed with which healthy participants initiated leftward and rightward reaches (without visual feedback) prior to and following adaptation to either 17° leftward (n = 16) or 17° rightward (n = 15) shifting prisms. Our results indicated that, following adaptation, participants were significantly faster to initiate reaches towards targets located in the direction opposite the prism shift. That is, participants were faster to initiate reaches to right targets following leftward prism adaptation and were faster to initiate reaches to left targets following rightward prism adaptation. Overall, these results are consistent with the idea that prism adaptation can influence the speed with which a reach can be initiated toward a target in the direction opposite the prism shift, possibly through altering activity in neural circuits involved in reach planning.


Assuntos
Adaptação Fisiológica/fisiologia , Pós-Efeito de Figura/fisiologia , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Lentes , Masculino , Adulto Jovem
20.
Neuroimage ; 155: 1-9, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28438667

RESUMO

The face perception system flexibly adjusts its neural responses to current face exposure, inducing aftereffects in the perception of subsequent faces. For instance, adaptation to expanded faces makes undistorted faces appear compressed, and adaptation to compressed faces makes undistorted faces appear expanded. Such distortion aftereffects have been proposed to result from renormalization, in which the visual system constantly updates a prototype according to the adaptors' characteristics and evaluates subsequent faces relative to that. However, although consequences of adaptation are easily observed in behavioral aftereffects, it has proven difficult to observe renormalization during adaptation itself. Here we directly measured brain responses during adaptation to establish a neural correlate of renormalization. Given that the face-evoked occipito-temporal P2 event-related brain potential has been found to increase with face prototypicality, we reasoned that the adaptor-elicited P2 could serve as an electrophysiological indicator for renormalization. Participants adapted to sequences of four distorted (compressed or expanded) or undistorted faces, followed by a slightly distorted test face, which they had to classify as undistorted or distorted. We analysed ERPs evoked by each of the adaptors and found that P2 (but not N170) amplitudes evoked by consecutive adaptor faces exhibited an electrophysiological pattern of renormalization during adaptation to distorted faces: P2 amplitudes evoked by both compressed and expanded adaptors significantly increased towards asymptotic levels as adaptation proceeded. P2 amplitudes were smallest for the first adaptor, significantly larger for the second, and yet larger for the third adaptor. We conclude that the sensitivity of the occipito-temporal P2 to the perceived deviation of a face from the norm makes this component an excellent tool to study adaptation-induced renormalization.


Assuntos
Encéfalo/fisiologia , Pós-Efeito de Figura/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Adaptação Fisiológica/fisiologia , Adulto , Eletroencefalografia , Potenciais Evocados/fisiologia , Face , Feminino , Humanos , Masculino , Adulto Jovem
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