知觉负荷对面孔多重社会范畴加工的影响

为了考察知觉负荷理论对于面孔多重社会范畴加工机制解释的可能性, 我们采用两个反应时实验探讨了姓名判断是否会在不同的知觉负荷条件下受到面孔性别与种族信息的影响。实验1通过侧抑制范式考察姓名判断中面孔种族引发的干扰效应是否会受到知觉负荷水平的调节。结果发现, 姓名判断的反应时间会随着负荷水平的提高显著延长, 即面孔种族引发的干扰效应不会随着负荷水平的提高而消失。实验2继续通过侧抑制范式考察了姓名判断中面孔性别引发的干扰效应是否会在不同知觉负荷水平下出现差异。结果发现, 在低负荷水平下, 个体在不一致条件下的反应时长于一致条件下的反应时, 并且被试会倾向于将中性名字的性别判断为与面孔的性别一致。在高负荷水平下, 个体的反应时在一致和不一致条件下没有显著差异, 并且被试对中性名字的性别判断属于随机猜测水平。上述结果表明, 种族加工具有自下而上的强制性加工的特点; 性别加工是受到注意资源调节的自上而下加工, 具有一定的灵活性。     

The development of visual search in infants and very young children.

In two experiments, 90 1- to 3-year-olds were trained in a new nonverbal task to touch a video screen that displayed a unique target resembling a popular television character. The target appeared among varying numbers of distractors that resembled another familiar television character and was either a uniquely colored shape (the feature search task) or a unique color-shape combination (the conjunction search task). Each correct response triggered a sound and produced four animated objects on the screen. Irrespective of age and experimental design (between-subjects or within-subjects), children's reaction time (RT) patterns resembled those obtained from adults in corresponding search tasks: The RT slope for feature search was flat and independent of distractor number, whereas the RT slope for conjunction search increased linearly with distractor number. These results extend visual search effects found with adults to infants and very young children and suggest that the basic perceptual processes underlying visual search are qualitatively invariant over ontogeny.     

Molyneux' question redux

After more than three centuries, Molyneux's question continues to challenge our understanding of cognition and perceptual systems. Locke, the original recipient of the question, approached it as a theoretical exercise relevant to long-standing philosophical issues, such as nativism, the possibility of common sensibles, and the empiricism-rationalism debate. However, philosophers were quick to adopt the experimentalist's stance as soon as they became aware of recoveries from congenital blindness through ophtalmic surgery. Such recoveries were widely reported to support empiricist positions, suggesting that the question had found its empirical answer. Contrary to this common view, we argue that studies of patients recovering from early blindness through surgery cannot provide an answer. In fact, because of the very nature of such ophtalmological interventions it is impossible to test the question in the empirical conditions outlined by Molyneux. Thus we propose that Molyneux's question be treated as an early thought experiment of a specific kind. Although thought experiments of this kind cannot be turned into actual experimental conditions, they provide a conceptual restructuring of theories. Such restructuring in turn leads to new predictions that can then be tested by normal experiments. In accord with this interpretation, we show that Molyneux's question can be analyzed into a hierarchy of specific questions about vision in its phenomenal and sensory-motor components. Some of these questions do lead to actual experimental conditions that could be studied empirically.     

Perceptual classes established with forced-choice primary generalization tests and transfer of function

In Experiment 1, 20 college students learned two identity conditional discriminations using squares that differed in interior-fill percentage (called Fill23 and Fill77). A two-choice generalization test was then presented with number of test trials varied across groups of subjects. The test samples were 19 squares that ranged in fill value from 23% to 77%; the comparisons were squares with Fill23 and Fill77. The resulting gradients did not vary as a function of number of test trials. When the generalization test was repeated with a third comparison, "neither," the ranges of fill values that occasioned the exclusive selection of Fill23 or Fill77 were direct functions of the number of prior two-choice generalization trials. Finally, a disriminability test revealed that Fill23 and Fill77 were disciminable from the intermediate fill values. In Experiment 2, perceptual classes were established with 5 new students using 760 forced-choice generalization test trials. The student were then trained to select a different glyph in the presence of Fill23 and Fill77, followed by a three-choice generalization test in which the 19 fill stimuli served as samples and the two glyphs served as comparisons. The gradients ovelapped with those previously obtained during the three-choice generalization test that used Fill23 and Fill77 as comparisons. Finally, a discriminability test showed that many adjacent stimuli along thc fill dimension were discriminable from each other. Together, the results of both experiments suggest that ranges of fill-based stimuli functioned as members of perceptual classes, and each class also functioned as a transfer network for a new selection-based response.     

Gaze behaviour of experienced and novice beach lifeguards – An exploratory in situ study

For lifeguards, recognizing a swimmer in trouble is a key factor in the rescue process. Although reports show that lifeguards outperform non‐lifeguards in their surveillance task, it is unclear to what extent this difference is reflected in gaze behaviour. In the current study, gaze behaviour of nine novice and seven experienced beach lifeguards was recorded for 45 min while they were on active duty. Results showed that fixation duration of experienced lifeguards was longer and more variable than that of novice lifeguards, and that these differences were more pronounced when looking at the task‐relevant region (i.e., swimming zone). Compared to experienced lifeguards, novices were found to be more distracted by the task‐irrelevant regions when there were more people swimming. These findings suggest that experienced lifeguards use a more flexible and task‐related gaze strategy, and that there might be differences in visual information processing between novice and experienced beach lifeguards.     

Visual body-size adaptation and estimation of tactile distance

Estimating the size of bodies is crucial for interactions with physical and social environments. Body-size perception is malleable and can be altered using visual adaptation paradigms. However, it is unclear whether such visual adaptation effects also transfer to other modalities and influence, for example, the perception of tactile distances. In this study, we employed a visual adaptation paradigm. Participants were exposed to images of expanded or contracted versions of self- or other-identity bodies. Before and after this adaptation, they were asked to manipulate the width of body stimuli to appear as ‘normal’ as possible. We replicated an effect of visual adaptation such that the body-size selected as most ‘normal’ was larger after exposure to expanded and thinner after exposure to contracted adaptation stimuli. In contrast, we did not find evidence that this adaptation effect transfers to distance estimates for paired tactile stimuli delivered to the abdomen. A Bayesian analysis showed that our data provide moderate evidence that there is no effect of visual body-size adaptation on the estimation of spatial parameters in a tactile task. This suggests that visual body-size adaptation effects do not transfer to somatosensory body-size representations.     

Perceptual load affects change blindness in a real‐world interaction

Change blindness is the striking inability to detect seemingly obvious changes that occur between views of a scene. The current study assessed perceptual load as a factor that may affect change blindness for human faces. The study had participants (n = 103) interact with a researcher in a testing room that imposed low or high perceptual load. Midway through the conversation, the researcher was replaced by another person. Thirty‐nine percent of participants failed to detect the change. There was a significant effect of perceptual load, with greater change detection under low load (71%) than high load (52%). This research suggests that the perceptual load imposed by a task may have a significant effect on the likelihood of change blindness and ought to be considered in future research.     

Are emotions perceptions of value (and why this matters)? A review essay of Christine Tappolet’s Emotions,Values, and Agency

In Emotions, Values, and Agency, Christine Tappolet develops a sophisticated, perceptual theory of emotions and their role in wide range of issues in value theory and epistemology. In this paper, we raise three worries about Tappolet's proposal.     

Why do we need perceptual content?

Most representationalists argue that perceptual experience has to be representational because phenomenal looks are, by themselves, representational. Charles Travis (2004 Travis, C. (2004). The silence of the senses. Mind, 113, 57–94.[Crossref], [Web of Science ®] , [Google Scholar]) argues that looks cannot represent. I argue that perceptual experience has to be representational due to the way the visual system works.