Harnessing the wandering mind: The role of perceptual load

Perceptual load is a key determinant of distraction by task-irrelevant stimuli (e.g., Lavie, N. (2005). Distracted and confused?: Selective attention under load. Trends in Cognitive Sciences, 9, 75-82). Here we establish the role of perceptual load in determining an internal form of distraction by task-unrelated thoughts (TUTs or “mind-wandering”).Four experiments demonstrated reduced frequency of TUTs with high compared to low perceptual load in a visual-search task. Alternative accounts in terms of increased demands on responses, verbal working memory or motivation were ruled out and clear effects of load were found for unintentional TUTs. Individual differences in load effects on internal (TUTs) and external (response-competition) distractors were correlated. These results suggest that exhausting attentional capacity in task-relevant processing under high perceptual load can reduce processing of task-irrelevant information from external and internal sources alike.     

Children’s representations of facial expression and identity: Identity-contingent expression aftereffects

This investigation used adaptation aftereffects to examine developmental changes in the perception of facial expressions. Previous studies have shown that adults’ perceptions of ambiguous facial expressions are biased following adaptation to intense expressions. These expression aftereffects are strong when the adapting and probe expressions share the same facial identity but are mitigated when they are posed by different identities. We extended these findings by comparing expression aftereffects and categorical boundaries in adults versus 5- to 9-year-olds (n = 20/group). Children displayed adult-like aftereffects and categorical boundaries for happy/sad by 7 years of age and for fear/anger by 9 years of age. These findings suggest that both children and adults perceive expressions according to malleable dimensions in which representations of facial expression are partially integrated with facial identity.     

类别表征与策略的脑科学研究及对思维教学的启示

脑科学研究表明,分类中对物体的知觉表征激活颞下叶皮层和颞中区等区域;语义表征激活前额皮层等。语义加工和知觉表征相互作用的脑机制表现为额区与视觉区域间信息的传递、提取。分类策略主要有规则策略和相似性策略两种。规则策略激活额区等广泛区域;相似性策略与视觉区域相关,包含着对个别样例的记忆过程。基于以上研究结果,本文从学习材料的表征和对材料进行表征时的策略两个方面为思维教学提出了一些建议。     

Perceptual and positional saliencies influence children’s sequence learning differently with age and instructions at test

There is growing evidence that, faced with a complex environment, participants subdivide the incoming information into small perceptual units, called chunks. Although statistical properties have been identified as playing a key role in chunking, we wanted to determine whether perceptual (repetitions) and positional (initial units) features might provide immediate guidance for the parsing of information into chunks. Children aged 5 and 8 years were exposed to sequences of 3, 4, or 5 colours. Sequence learning was assessed either through an explicit generation test (Experiment 1) or through a recognition test (Experiment 2). Experiment 1 showed that perceptual and positional saliencies benefited learning and that sensitivity to repetitions was age dependent and permitted the formation of longer chunks (trigrams) in the oldest children. Experiment 2 suggested that children became sensitive to perceptual and positional saliencies regardless of age and that the both types of saliencies supported the formation of longer chunks in the oldest children. The discussion focuses on the multiple factors intervening in sequence learning and their differential effects as a function of the instructions used at test to assess sequence learning.     

Motor response influences perceptual awareness judgements

What is the relation between perceptual awareness and action? In this study we tested the hypothesis that motor response influences perceptual awareness judgements. We used a perceptual discrimination task in which presentation of the stimulus was immediately followed by a cue requiring a motor response that was irrelevant to the task but could be the same, opposite, or neutral to the correct response to the stimulus. After responding to the cue, participants rated their stimulus awareness using the Perceptual Awareness Scale, and then carried out their discrimination response. Participants reported a higher level of stimulus awareness after carrying out responses that were either congruent or incongruent with the response required by the stimulus, compared to the neutral condition. The results suggest that the motor response overlapping with a potential response to the stimulus provides information about the outcome of decision process and increases the reported awareness of stimuli.     

Planning Beyond the Next Trial in Adaptive Experiments: A Dynamic Programming Approach

Experimentation is at the heart of scientific inquiry. In the behavioral and neural sciences, where only a limited number of observations can often be made, it is ideal to design an experiment that leads to the rapid accumulation of information about the phenomenon under study. Adaptive experimentation has the potential to accelerate scientific progress by maximizing inferential gain in such research settings. To date, most adaptive experiments have relied on myopic, one‐step‐ahead strategies in which the stimulus on each trial is selected to maximize inference on the next trial only. A lingering question in the field has been how much additional benefit would be gained by optimizing beyond the next trial. A range of technical challenges has prevented this important question from being addressed adequately. This study applies dynamic programming (DP), a technique applicable for such full‐horizon, “global” optimization, to model‐based perceptual threshold estimation, a domain that has been a major beneficiary of adaptive methods. The results provide insight into conditions that will benefit from optimizing beyond the next trial. Implications for the use of adaptive methods in cognitive science are discussed.     

Improving Human‐Machine Cooperative Classification Via Cognitive Theories of Similarity

Acquiring perceptual expertise is slow and effortful. However, untrained novices can accurately make difficult classification decisions (e.g., skin‐lesion diagnosis) by reformulating the task as similarity judgment. Given a query image and a set of reference images, individuals are asked to select the best matching reference. When references are suitably chosen, the procedure yields an implicit classification of the query image. To optimize reference selection, we develop and evaluate a predictive model of similarity‐based choice. The model builds on existing psychological literature and accommodates stochastic, dynamic shifts of attention among visual feature dimensions. We perform a series of human experiments with two stimulus types (rectangles, faces) and nine classification tasks to validate the model and to demonstrate the model's potential to boost performance. Our system achieves high accuracy for participants who are naive as to the classification task, even when the classification task switches from trial to trial.     

有关具身认知的三种理论模型

具身认知强调了身体在认知中的关键作用,主张身体的构造和状态、身体的物理属性及其大脑与身体的特殊感觉—运动通道对认知的形成产生了根本影响。具身认知的相关理论虽然直接或者间接承认身体对心智的塑造关系,但是存在一些观点的不一致,导致具身认知理论难以统一到相同的框架上来,具身认知大致可以归结为三种模型:概念隐喻理论,知觉符号理论和感知运动模拟隐喻理论。     

Global shape integration and illusory form perception in the absence of awareness

Previous research on perceptual organization operations still provides contradictory evidence on whether the integration of sparse local elements into coherently unified shapes and the construction of the illusory form are accomplished without the need of awareness. In the present study, three experiments were conducted in which participants were presented with masked (Experiment 1, SOA = 27 ms; Experiment 2; SOA = 53 ms) and unmasked (Experiment 3) primes consisting of geometric shapes (a square or a diamond) that could be congruent or incongruent with subsequent probe stimuli (square vs. diamond). Furthermore, the primes were divided into: a grouping condition (where local elements may group together into global shapes), an illusory condition (where the arrangement of local elements produced illusory shapes) and a hybrid condition (where both operations were presented simultaneously). While no priming effects were found for the shortest SOA (27 ms), both grouping and illusory primes produced significant priming effects in the longer SOA (53 ms). On the other hand, results in Experiment 3 (unmasked) showed strong priming effects for the grouping of the inducers in both the grouping and the hybrid conditions, and also a significant but weaker priming effect for the illusory condition. Overall, our results support the possibility of the integration of local visual features into a global shape in the absence of awareness and, likewise, they suggest an early –subliminal– construction of the illusory shape, implying that feedback projections from higher to lower visual areas are not crucial in the construction of the illusory form.