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1.
Scand J Psychol ; 65(4): 628-638, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38380530

RESUMO

The Alabama parenting questionnaire (APQ) is a commonly used instrument for assessing parenting practices and evaluating treatment outcomes of parent-training interventions targeting child conduct problems. In the present study we translated and developed a Swedish version of the APQ parent version and tested it on a community sample of 799 parents of children between 6 and 15 years with diverse socioeconomic backgrounds. Data were collected through an online survey distributed through school newsletters and social media. Exploratory factor analysis (EFA) suggested a five-factor model with 23 items. Four of these factors correspond to the subscales suggested in the original version of the APQ: inconsistent discipline, poor monitoring, involvement, and positive parenting. The fifth subscale from the original APQ, corporal punishment, did not show up as a factor in our data sample. Instead, a new factor, which we refer to as contingency management, was revealed. A confirmatory factor analysis further suggested some misalignment between the original APQ subscale structure and our sample, which we interpret as a signal that the instrument may need refinement to better reflect contemporary parenting methods in diverse cultural contexts. Despite this limitation, and with the exclusion of the corporal punishment subscale, which should be employed judiciously, our results suggest that the Swedish version of the APQ can be a useful instrument in measuring parenting practices in Sweden. We present norm data stratified by child age, which practitioners and researchers can use as a reference for assessment of parenting practices in the Swedish population.


Assuntos
Poder Familiar , Psicometria , Humanos , Poder Familiar/psicologia , Psicometria/normas , Psicometria/instrumentação , Feminino , Masculino , Criança , Suécia , Adolescente , Inquéritos e Questionários/normas , Adulto , Análise Fatorial , Pais , Pessoa de Meia-Idade
2.
PLoS One ; 18(1): e0280257, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36649241

RESUMO

Previous work has shown that humans distribute their visual working memory (VWM) resources flexibly across items: the higher the importance of an item, the better it is remembered. A related, but much less studied question is whether people also have control over the total amount of VWM resource allocated to a task. Here, we approach this question by testing whether increasing monetary incentives results in better overall VWM performance. In three experiments, subjects performed a delayed-estimation task on the Amazon Turk platform. In the first two experiments, four groups of subjects received a bonus payment based on their performance, with the maximum bonus ranging from $0 to $10 between groups. We found no effect of the amount of bonus on intrinsic motivation or on VWM performance in either experiment. In the third experiment, reward was manipulated on a trial-by-trial basis using a within-subjects design. Again, no evidence was found that VWM performance depended on the magnitude of potential reward. These results suggest that encoding quality in visual working memory is insensitive to monetary reward, which has implications for resource-rational theories of VWM.


Assuntos
Cognição , Memória de Curto Prazo , Humanos , Rememoração Mental , Motivação , Recompensa , Percepção Visual
3.
Psychol Rev ; 130(5): 1383-1400, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36633996

RESUMO

Extensive research in the behavioral sciences has addressed people's ability to learn stationary probabilities, which stay constant over time, but only recently have there been attempts to model the cognitive processes whereby people learn-and track-nonstationary probabilities. In this context, the old debate on whether learning occurs by the gradual formation of associations or by occasional shifts between hypotheses representing beliefs about distal states of the world has resurfaced. Gallistel et al. (2014) pitched the two theories against each other in a nonstationary probability learning task. They concluded that various qualitative patterns in their data were incompatible with trial-by-trial associative learning and could only be explained by a hypothesis-testing model. Here, we contest that claim and demonstrate that it was premature. First, we argue that their experimental paradigm consisted of two distinct tasks: probability tracking (an estimation task) and change detection (a decision-making task). Next, we present a model that uses the (associative) delta learning rule for the probability tracking task and bounded evidence accumulation for the change detection task. We find that this combination of two highly established theories accounts well for all qualitative phenomena and outperforms the alternative model proposed by Gallistel et al. (2014) in a quantitative model comparison. In the spirit of cumulative science, we conclude that current experimental data on human learning of nonstationary probabilities can be explained as a combination of associative learning and bounded evidence accumulation and does not require a new model. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

4.
Cognition ; 226: 105160, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35660344

RESUMO

Base rate neglect refers to people's apparent tendency to underweight or even ignore base rate information when estimating posterior probabilities for events, such as the probability that a person with a positive cancer-test outcome actually does have cancer. While often replicated, almost all evidence for the phenomenon comes from studies that used problems with extremely low base rates, high hit rates, and low false alarm rates. It is currently unclear whether the effect generalizes to reasoning problems outside this "corner" of the entire problem space. Another limitation of previous studies is that they have focused on describing empirical patterns of the effect at the group level and not so much on the underlying strategies and individual differences. Here, we address these two limitations by testing participants on a broader problem space and modeling their responses at a single-participant level. We find that the empirical patterns that have served as evidence for base-rate neglect generalize to a larger problem space, albeit with large individual differences in the extent with which participants "neglect" base rates. In particular, we find a bi-modal distribution consisting of one group of participants who almost entirely ignore the base rate and another group who almost entirely account for it. This heterogeneity is reflected in the cognitive modeling results: participants in the former group were best captured by a linear-additive model, while participants in the latter group were best captured by a Bayesian model. We find little evidence for heuristic models. Altogether, these results suggest that the effect known as "base-rate neglect" generalizes to a large set of reasoning problems, but varies largely across participants and may need a reinterpretation in terms of the underlying cognitive mechanisms.


Assuntos
Cognição , Resolução de Problemas , Teorema de Bayes , Humanos , Probabilidade
5.
PLoS Comput Biol ; 15(4): e1006465, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30998675

RESUMO

Optimal Bayesian models have been highly successful in describing human performance on perceptual decision-making tasks, such as cue combination and visual search. However, recent studies have argued that these models are often overly flexible and therefore lack explanatory power. Moreover, there are indications that neural computation is inherently imprecise, which makes it implausible that humans would perform optimally on any non-trivial task. Here, we reconsider human performance on a visual-search task by using an approach that constrains model flexibility and tests for computational imperfections. Subjects performed a target detection task in which targets and distractors were tilted ellipses with orientations drawn from Gaussian distributions with different means. We varied the amount of overlap between these distributions to create multiple levels of external uncertainty. We also varied the level of sensory noise, by testing subjects under both short and unlimited display times. On average, empirical performance-measured as d'-fell 18.1% short of optimal performance. We found no evidence that the magnitude of this suboptimality was affected by the level of internal or external uncertainty. The data were well accounted for by a Bayesian model with imperfections in its computations. This "imperfect Bayesian" model convincingly outperformed the "flawless Bayesian" model as well as all ten heuristic models that we tested. These results suggest that perception is founded on Bayesian principles, but with suboptimalities in the implementation of these principles. The view of perception as imperfect Bayesian inference can provide a middle ground between traditional Bayesian and anti-Bayesian views.


Assuntos
Percepção Visual/fisiologia , Teorema de Bayes , Biologia Computacional , Tomada de Decisões , Teoria da Decisão , Discriminação Psicológica , Heurística , Humanos , Modelos Psicológicos , Estimulação Luminosa , Incerteza
6.
PLoS One ; 14(2): e0207502, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30759086

RESUMO

Humans can estimate numerosities-such as the number sheep in a flock-without deliberate counting. A number of biases have been identified in these estimates, which seem primarily rooted in the spatial organization of objects (grouping, symmetry, etc). Most previous studies on the number sense used static stimuli with extremely brief exposure times. However, outside the laboratory, visual scenes are often dynamic and freely viewed for prolonged durations (e.g., a flock of moving sheep). The purpose of the present study is to examine grouping-induced numerosity biases in stimuli that more closely mimic these conditions. To this end, we designed two experiments with limited-dot-lifetime displays (LDDs), in which each dot is visible for a brief period of time and replaced by a new dot elsewhere after its disappearance. The dynamic nature of LDDs prevents subjects from counting even when they are free-viewing a stimulus under prolonged presentation. Subjects estimated the number of dots in arrays that were presented either as a single group or were segregated into two groups by spatial clustering, dot size, dot color, or dot motion. Grouping by color and motion reduced perceived numerosity compared to viewing them as a single group. Moreover, the grouping effect sizes between these two features were correlated, which suggests that the effects may share a common, feature-invariant mechanism. Finally, we find that dot size and total stimulus area directly affect perceived numerosity, which makes it difficult to draw reliable conclusions about grouping effects induced by spatial clustering and dot size. Our results provide new insights into biases in numerosity estimation and they demonstrate that the use of LDDs is an effective method to study the human number sense under prolonged viewing.


Assuntos
Conceitos Matemáticos , Percepção Visual , Adulto , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Estimulação Luminosa , Pensamento , Fatores de Tempo , Adulto Jovem
7.
Elife ; 72018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-30084356

RESUMO

Encoding precision in visual working memory decreases with the number of encoded items. Here, we propose a normative theory for such set size effects: the brain minimizes a weighted sum of an error-based behavioral cost and a neural encoding cost. We construct a model from this theory and find that it predicts set size effects. Notably, these effects are mediated by probing probability, which aligns with previous empirical findings. The model accounts well for effects of both set size and probing probability on encoding precision in nine delayed-estimation experiments. Moreover, we find support for the prediction that the total amount of invested resource can vary non-monotonically with set size. Finally, we show that it is sometimes optimal to encode only a subset or even none of the relevant items in a task. Our findings raise the possibility that cognitive "limitations" arise from rational cost minimization rather than from constraints.


Assuntos
Memória de Curto Prazo , Modelos Neurológicos , Percepção Visual , Humanos
8.
J Exp Psychol Hum Percept Perform ; 43(6): 1084-1097, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28263625

RESUMO

Humans as well as some nonhuman animals can estimate object numerosities-such as the number of sheep in a flock-without explicit counting. Here, we report on a negative time-order effect (TOE) in this type of judgment: When nonsymbolic numerical stimuli are presented sequentially, the second stimulus is overestimated compared to the first. We examined this "recent is more" effect in two comparative judgment tasks: larger-smaller discrimination and same-different discrimination. Ideal-observer modeling revealed evidence for a TOE in 88.2% of the individual data sets. Despite large individual differences in effect size, there was strong consistency in effect direction: 87.3% of the identified TOEs were negative. The average effect size was largely independent of task but did strongly depend on both stimulus magnitude and interstimulus interval. Finally, we used an estimation task to obtain insight into the origin of the effect. We found that subjects tend to overestimate both stimuli but the second one more strongly than the first one. Overall, our findings are highly consistent with findings from studies on TOEs in nonnumerical judgments, which suggests a common underlying mechanism. (PsycINFO Database Record


Assuntos
Julgamento/fisiologia , Conceitos Matemáticos , Reconhecimento Visual de Modelos/fisiologia , Adulto , Feminino , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
9.
Psychol Rev ; 124(2): 197-214, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28221087

RESUMO

Although visual working memory (VWM) has been studied extensively, it is unknown how people form confidence judgments about their memories. Peirce (1878) speculated that Fechner's law-which states that sensation is proportional to the logarithm of stimulus intensity-might apply to confidence reports. Based on this idea, we hypothesize that humans map the precision of their VWM contents to a confidence rating through Fechner's law. We incorporate this hypothesis into the best available model of VWM encoding and fit it to data from a delayed-estimation experiment. The model provides an excellent account of human confidence rating distributions as well as the relation between performance and confidence. Moreover, the best-fitting mapping in a model with a highly flexible mapping closely resembles the logarithmic mapping, suggesting that no alternative mapping exists that accounts better for the data than Fechner's law. We propose a neural implementation of the model and find that this model also fits the behavioral data well. Furthermore, we find that jointly fitting memory errors and confidence ratings boosts the power to distinguish previously proposed VWM encoding models by a factor of 5.99 compared to fitting only memory errors. Finally, we show that Fechner's law also accounts for metacognitive judgments in a word recognition memory task, which is a first indication that it may be a general law in metacognition. Our work presents the first model to jointly account for errors and confidence ratings in VWM and could lay the groundwork for understanding the computational mechanisms of metacognition. (PsycINFO Database Record


Assuntos
Memória de Curto Prazo , Processos Mentais , Metacognição , Percepção Visual , Encéfalo , Humanos , Modelos Psicológicos
10.
Curr Biol ; 26(23): 3157-3168, 2016 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-27866891

RESUMO

Demanding tasks often require a series of decisions to reach a goal. Recent progress in perceptual decision-making has served to unite decision accuracy, speed, and confidence in a common framework of bounded evidence accumulation, furnishing a platform for the study of such multi-stage decisions. In many instances, the strategy applied to each decision, such as the speed-accuracy trade-off, ought to depend on the accuracy of the previous decisions. However, as the accuracy of each decision is often unknown to the decision maker, we hypothesized that subjects may carry forward a level of confidence in previous decisions to affect subsequent decisions. Subjects made two perceptual decisions sequentially and were rewarded only if they made both correctly. The speed and accuracy of individual decisions were explained by noisy evidence accumulation to a terminating bound. We found that subjects adjusted their speed-accuracy setting by elevating the termination bound on the second decision in proportion to their confidence in the first. The findings reveal a novel role for confidence and a degree of flexibility, hitherto unknown, in the brain's ability to rapidly and precisely modify the mechanisms that control the termination of a decision.


Assuntos
Tomada de Decisões , Comportamento de Escolha/fisiologia , Humanos , Fatores de Tempo
11.
PLoS One ; 11(3): e0149402, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26963498

RESUMO

In laboratory visual search experiments, distractors are often statistically independent of each other. However, stimuli in more naturalistic settings are often correlated and rarely independent. Here, we examine whether human observers take stimulus correlations into account in orientation target detection. We find that they do, although probably not optimally. In particular, it seems that low distractor correlations are overestimated. Our results might contribute to bridging the gap between artificial and natural visual search tasks.


Assuntos
Estimulação Luminosa , Percepção Visual , Feminino , Humanos , Masculino , Modelos Teóricos , Psicometria
12.
PLoS One ; 11(2): e0148504, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26863625

RESUMO

Cueing attention after the disappearance of visual stimuli biases which items will be remembered best. This observation has historically been attributed to the influence of attention on memory as opposed to subjective visual experience. We recently challenged this view by showing that cueing attention after the stimulus can improve the perception of a single Gabor patch at threshold levels of contrast. Here, we test whether this retro-perception actually increases the frequency of consciously perceiving the stimulus, or simply allows for a more precise recall of its features. We used retro-cues in an orientation-matching task and performed mixture-model analysis to independently estimate the proportion of guesses and the precision of non-guess responses. We find that the improvements in performance conferred by retrospective attention are overwhelmingly determined by a reduction in the proportion of guesses, providing strong evidence that attracting attention to the target's location after its disappearance increases the likelihood of perceiving it consciously.


Assuntos
Atenção/fisiologia , Estado de Consciência/fisiologia , Sinais (Psicologia) , Adolescente , Adulto , Algoritmos , Feminino , Humanos , Masculino , Memória , Orientação/fisiologia , Probabilidade , Psicometria , Tempo de Reação , Reprodutibilidade dos Testes , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Adulto Jovem
13.
Elife ; 5: e12192, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26829590

RESUMO

Decisions are accompanied by a degree of confidence that a selected option is correct. A sequential sampling framework explains the speed and accuracy of decisions and extends naturally to the confidence that the decision rendered is likely to be correct. However, discrepancies between confidence and accuracy suggest that confidence might be supported by mechanisms dissociated from the decision process. Here we show that this discrepancy can arise naturally because of simple processing delays. When participants were asked to report choice and confidence simultaneously, their confidence, reaction time and a perceptual decision about motion were explained by bounded evidence accumulation. However, we also observed revisions of the initial choice and/or confidence. These changes of mind were explained by a continuation of the mechanism that led to the initial choice. Our findings extend the sequential sampling framework to vacillation about confidence and invites caution in interpreting dissociations between confidence and accuracy.


Assuntos
Tomada de Decisões/fisiologia , Modelos Neurológicos , Comportamento de Escolha/fisiologia , Voluntários Saudáveis , Tempo de Reação
14.
Vision Res ; 116(Pt B): 179-93, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25584425

RESUMO

In tasks such as visual search and change detection, a key question is how observers integrate noisy measurements from multiple locations to make a decision. Decision rules proposed to model this process have fallen into two categories: Bayes-optimal (ideal observer) rules and ad-hoc rules. Among the latter, the maximum-of-outputs (max) rule has been the most prominent. Reviewing recent work and performing new model comparisons across a range of paradigms, we find that in all cases except for one, the optimal rule describes human data as well as or better than every max rule either previously proposed or newly introduced here. This casts doubt on the utility of the max rule for understanding perceptual decision-making.


Assuntos
Simulação por Computador , Detecção de Sinal Psicológico/fisiologia , Percepção Visual/fisiologia , Atenção , Teorema de Bayes , Tomada de Decisões , Humanos
15.
Atten Percept Psychophys ; 76(7): 2117-35, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24719235

RESUMO

Performance on visual working memory tasks decreases as more items need to be remembered. Over the past decade, a debate has unfolded between proponents of slot models and slotless models of this phenomenon (Ma, Husain, Bays (Nature Neuroscience 17, 347-356, 2014). Zhang and Luck (Nature 453, (7192), 233-235, 2008) and Anderson, Vogel, and Awh (Attention, Perception, Psychophys 74, (5), 891-910, 2011) noticed that as more items need to be remembered, "memory noise" seems to first increase and then reach a "stable plateau." They argued that three summary statistics characterizing this plateau are consistent with slot models, but not with slotless models. Here, we assess the validity of their methods. We generated synthetic data both from a leading slot model and from a recent slotless model and quantified model evidence using log Bayes factors. We found that the summary statistics provided at most 0.15 % of the expected model evidence in the raw data. In a model recovery analysis, a total of more than a million trials were required to achieve 99 % correct recovery when models were compared on the basis of summary statistics, whereas fewer than 1,000 trials were sufficient when raw data were used. Therefore, at realistic numbers of trials, plateau-related summary statistics are highly unreliable for model comparison. Applying the same analyses to subject data from Anderson et al. (Attention, Perception, Psychophys 74, (5), 891-910, 2011), we found that the evidence in the summary statistics was at most 0.12 % of the evidence in the raw data and far too weak to warrant any conclusions. The evidence in the raw data, in fact, strongly favored the slotless model. These findings call into question claims about working memory that are based on summary statistics.


Assuntos
Memória de Curto Prazo/fisiologia , Modelos Estatísticos , Teorema de Bayes , Humanos , Percepção Visual/fisiologia
16.
Psychol Rev ; 121(1): 124-49, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24490791

RESUMO

Three questions have been prominent in the study of visual working memory limitations: (a) What is the nature of mnemonic precision (e.g., quantized or continuous)? (b) How many items are remembered? (c) To what extent do spatial binding errors account for working memory failures? Modeling studies have typically focused on comparing possible answers to a single one of these questions, even though the result of such a comparison might depend on the assumed answers to both others. Here, we consider every possible combination of previously proposed answers to the individual questions. Each model is then a point in a 3-factor model space containing a total of 32 models, of which only 6 have been tested previously. We compare all models on data from 10 delayed-estimation experiments from 6 laboratories (for a total of 164 subjects and 131,452 trials). Consistently across experiments, we find that (a) mnemonic precision is not quantized but continuous and not equal but variable across items and trials; (b) the number of remembered items is likely to be variable across trials, with a mean of 6.4 in the best model (median across subjects); (c) spatial binding errors occur but explain only a small fraction of responses (16.5% at set size 8 in the best model). We find strong evidence against all 6 documented models. Our results demonstrate the value of factorial model comparison in working memory.


Assuntos
Interpretação Estatística de Dados , Memória de Curto Prazo/fisiologia , Modelos Psicológicos , Modelos Estatísticos , Atenção , Análise Fatorial , Humanos , Funções Verossimilhança , Testes Neuropsicológicos/estatística & dados numéricos , Reconhecimento Visual de Modelos/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Retenção Psicológica/fisiologia , Distribuições Estatísticas
17.
Ecol Evol ; 3(9): 3047-62, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24101993

RESUMO

Genetic variation patterns within and between species may change along geographic gradients and at different spatial scales. This was revealed by microsatellite data at 29 loci obtained from 119 accessions of three Oryza series Sativae species in Asia Pacific: Oryza nivara Sharma and Shastry, O. rufipogon Griff., and O. meridionalis Ng. Genetic similarities between O. nivara and O. rufipogon across their distribution are evident in the clustering and ordination results and in the large proportion of shared alleles between these taxa. However, local-level species separation is recognized by Bayesian clustering and neighbor-joining analyses. At the regional scale, the two species seem more differentiated in South Asia than in Southeast Asia as revealed by F ST analysis. The presence of strong gene flow barriers in smaller spatial units is also suggested in the analysis of molecular variance (AMOVA) results where 64% of the genetic variation is contained among populations (as compared to 26% within populations and 10% among species). Oryza nivara (H E = 0.67) exhibits slightly lower diversity and greater population differentiation than O. rufipogon (H E = 0.70). Bayesian inference identified four, and at a finer structural level eight, genetically distinct population groups that correspond to geographic populations within the three taxa. Oryza meridionalis and the Nepalese O. nivara seemed diverged from all the population groups of the series, whereas the Australasian O. rufipogon appeared distinct from the rest of the species.

18.
J Vis ; 13(5)2013 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-23576114

RESUMO

Looking for a target in a visual scene becomes more difficult as the number of stimuli increases. In a signal detection theory view, this is due to the cumulative effect of noise in the encoding of the distractors, and potentially on top of that, to an increase of the noise (i.e., a decrease of precision) per stimulus with set size, reflecting divided attention. It has long been argued that human visual search behavior can be accounted for by the first factor alone. While such an account seems to be adequate for search tasks in which all distractors have the same, known feature value (i.e., are maximally predictable), we recently found a clear effect of set size on encoding precision when distractors are drawn from a uniform distribution (i.e., when they are maximally unpredictable). Here we interpolate between these two extreme cases to examine which of both conclusions holds more generally as distractor statistics are varied. In one experiment, we vary the level of distractor heterogeneity; in another we dissociate distractor homogeneity from predictability. In all conditions in both experiments, we found a strong decrease of precision with increasing set size, suggesting that precision being independent of set size is the exception rather than the rule.


Assuntos
Atenção/fisiologia , Percepção de Forma/fisiologia , Detecção de Sinal Psicológico/fisiologia , Percepção de Tamanho/fisiologia , Análise de Variância , Discriminação Psicológica/fisiologia , Feminino , Humanos , Masculino , Modelos Teóricos , Estimulação Luminosa/métodos , Percepção Visual/fisiologia
19.
PLoS Comput Biol ; 9(2): e1002927, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23468613

RESUMO

Change detection is a classic paradigm that has been used for decades to argue that working memory can hold no more than a fixed number of items ("item-limit models"). Recent findings force us to consider the alternative view that working memory is limited by the precision in stimulus encoding, with mean precision decreasing with increasing set size ("continuous-resource models"). Most previous studies that used the change detection paradigm have ignored effects of limited encoding precision by using highly discriminable stimuli and only large changes. We conducted two change detection experiments (orientation and color) in which change magnitudes were drawn from a wide range, including small changes. In a rigorous comparison of five models, we found no evidence of an item limit. Instead, human change detection performance was best explained by a continuous-resource model in which encoding precision is variable across items and trials even at a given set size. This model accounts for comparison errors in a principled, probabilistic manner. Our findings sharply challenge the theoretical basis for most neural studies of working memory capacity.


Assuntos
Biologia Computacional/métodos , Memória de Curto Prazo/fisiologia , Modelos Neurológicos , Adulto , Teorema de Bayes , Feminino , Humanos , Masculino , Estimulação Luminosa , Reprodutibilidade dos Testes , Análise e Desempenho de Tarefas
20.
PLoS One ; 7(6): e40216, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22768258

RESUMO

A key function of the brain is to interpret noisy sensory information. To do so optimally, observers must, in many tasks, take into account knowledge of the precision with which stimuli are encoded. In an orientation change detection task, we find that encoding precision does not only depend on an experimentally controlled reliability parameter (shape), but also exhibits additional variability. In spite of variability in precision, human subjects seem to take into account precision near-optimally on a trial-to-trial and item-to-item basis. Our results offer a new conceptualization of the encoding of sensory information and highlight the brain's remarkable ability to incorporate knowledge of uncertainty during complex perceptual decision-making.


Assuntos
Probabilidade , Percepção Visual/fisiologia , Adulto , Tomada de Decisões , Feminino , Humanos , Funções Verossimilhança , Masculino , Modelos Neurológicos , Estimulação Luminosa , Reprodutibilidade dos Testes , Adulto Jovem
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