Perceptual learning effect on decision and confidence thresholds

Practice can enhance of perceptual sensitivity, a well-known phenomenon called perceptual learning. However, the effect of practice on subjective perception has received little attention. We approach this problem from a visual psychophysics and computational modeling perspective. In a sequence of visual search experiments, subjects significantly increased the ability to detect a “trained target”. Before and after training, subjects performed two psychophysical protocols that parametrically vary the visibility of the “trained target”: an attentional blink and a visual masking task. We found that confidence increased after learning only in the attentional blink task. Despite large differences in some observables and task settings, we identify common mechanisms for decision-making and confidence. Specifically, our behavioral results and computational model suggest that perceptual ability is independent of processing time, indicating that changes in early cortical representations are effective, and learning changes decision criteria to convey choice and confidence.     

Verbalization of Decision Strategies in Multiple‐Cue Probabilistic Inference

In multiple‐cue probabilistic inference, people choose between alternatives based on several cues, each of which is differentially associated with an alternative's overall value. Various strategies have been proposed for probabilistic inference (e.g., weighted additive, tally, and take‐the‐best). These strategies differ in how many cue values they require to enact and in how they weight each cue. Do decision makers actually use any of these strategies? Ways to investigate this question include analyzing people's choices and the cues that they reveal. However, different strategies often predict the same decisions, and search behavior says nothing about whether or how people use the information that they acquire. In this research, we attempt to elucidate which strategies participants use in a multiple‐cue probabilistic inference task by examining verbal protocols, a high‐density source of process data. The promise of verbal data is in their utility for testing detailed information processing models. To that end, we apply protocol analysis in conjunction with computational simulations. We find converging evidence across outcome measures, search measures, and verbal reports that most participants use simplifying heuristics, namely take‐the‐best. Copyright © 2015 John Wiley & Sons, Ltd.     

Epistemic perceptualism and neo-sentimentalist objections

Epistemic Perceptualists claim that emotions are sources of immediate defeasible justification for evaluative propositions that can (and do) sometimes ground undefeated immediately justified evaluative beliefs. For example, fear can constitute the justificatory ground for a belief that some object or event is dangerous. Despite its attractiveness, the view is apparently vulnerable to several objections. In this paper, I provide a limited defence of Epistemic Perceptualism by responding to a family of objections which all take as a premise a popular and attractive view in value theory – Neo-Sentimentalism – according to which values are analysed in terms of fitting emotions.     

The interaction between social saliency and perceptual saliency

The ability to select visual targets in hierarchical stimuli can be affected by both perceptual saliency and social saliency. However, the functional relations between the effects are not understood. Here we examined whether these two factors interact or combine in an additive way. Participants first learnt to associate geometric shapes with three people (e.g., triangle–self, square–stranger). After learning the associations, participants were presented with compound stimuli (e.g., a global triangle formed by a set of local squares) and had to select a target at the global or local level. In Experiment 1 the task was to identify the person associated with the local or global shape. In Experiment 2 the task was simply to identify the shape. We manipulated perceptual saliency by blurring local elements to form perceptually global salient stimuli or by contrasting the colours of neighbouring local elements (red vs. white) to form perceptually local salient stimuli. In Experiment 1 (person discrimination) there was a strong effect of saliency on local targets (there were faster and more accurate responses to high than to low saliency targets) when social and perceptual saliency occurred at same level. However, both perceptual and social saliency effects were eliminated when the effect of saliency at one level competed with that at the other level. In Experiment 2 (shape discrimination), there were only effects of perceptual saliency. The data indicate that social saliency interacts with perceptual saliency when explicit social categorizations are made, consistent with both factors modulating a common process of visual selection.     

The objects of visuospatial short-term memory: Perceptual organization and change detection

We used a colour change-detection paradigm where participants were required to remember colours of six equally spaced circles. Items were superimposed on a background so as to perceptually group them within (a) an intact ring-shaped object, (b) a physically segmented but perceptually completed ring-shaped object, or (c) a corresponding background segmented into three arc-shaped objects. A nonpredictive cue at the location of one of the circles was followed by the memory items, which in turn were followed by a test display containing a probe indicating the circle to be judged same/different. Reaction times for correct responses revealed a same-object advantage; correct responses were faster to probes on the same object as the cue than to equidistant probes on a segmented object. This same-object advantage was identical for physically and perceptually completed objects, but was only evident in reaction times, and not in accuracy measures. Not only, therefore, is it important to consider object-level perceptual organization of stimulus elements when assessing the influence of a range of factors (e.g., number and complexity of elements) in visuospatial short-term memory, but a more detailed picture of the structure of information in memory may be revealed by measuring speed as well as accuracy.     

相对熟悉度和同音线索在谐音型歇后语理解中的作用

谐音型歇后语是汉语特殊的语汇表达形式, 对其加工常常需要通达后一语节的同音线索来完成语音、语义隐喻映射。本研究通过2个实验探讨相对熟悉度和同音线索类型对谐音型歇后语加工的作用。实验1结果表明, 在高熟悉度条件下, 被试对语汇的加工策略取决于歇后语的同音线索类型。当后一语节为同音字时, 加工较为快速; 当后一语节为谐音字时, 通达歇后语隐喻意义的路径受阻。对熟悉度较高的谐音型歇后语进行加工, 语义通达表现出预存性; 在缺乏同音线索的条件下, 语料加工时间较长, 反应准确率较低, 支持概念隐喻模型和概念合成假说。而对熟悉度较低的歇后语进行加工, 被试更倾向于采用即时(on-line)策略, 支持概念合成理论和基于心理模型的语用推理假说。实验2结果表明, 呈现“错误同音”线索对歇后语的加工形成干扰, 不支持概念合成理论和基于心理模型的语用推理理论。总的结果表明, 相对熟悉度和同音线索类型影响谐音型歇后语的通达, 谐音歇后语加工需要同时激活语音和语义两条通道。     

Rowing together: Interpersonal coordination dynamics with and without mechanical coupling

Although most research on interpersonal coordination focuses on perceptual forms of interaction, many interpersonal actions also involve interactions of mechanical nature. We examined the effect of mechanical coupling in a rowing task from a coupled oscillator perspective: 16 pairs of rowers rowed on ergometers that were physically connected through slides (mechanical coupling condition) or on separate ergometers (no mechanical coupling condition). They rowed in two patterns (in- and antiphase) and at two movement frequencies (20 and 30 strokes per minute). Seven out of sixteen pairs showed one or more coordinative breakdowns, which only occurred in the antiphase condition. The occurrence of these breakdowns was not affected by mechanical coupling, nor by movement frequency. For the other nine pairs, variability of steady state coordination was substantially lower in the mechanical coupling condition. Together, these results show that the increase in coupling strength through mechanical coupling stabilizes coordination, even more so for antiphase coordination.     

Forward inference in risky choice: Mapping gaze and decision processes

The study of cognitive processes is built on a close mapping between three components: overt gaze behavior, overt choice, and covert processes. To validate this overt–covert mapping in the domain of decision‐making, we collected eye‐movement data during decisions between risky gamble problems. Applying a forward inference paradigm, participants were instructed to use specific decision strategies to solve those gamble problems (maximizing expected values or applying different choice heuristics) during which gaze behavior was recorded. We revealed differences between overt behavior, as indicated by eye movements, and covert decision processes, instructed by the experimenter. However, our results show that the overt–covert mapping is for some eye‐movement measures not as close as expected by current decision theory, and hence question reverse inference as being prone to fallacies due to a violation of its prerequisite, that is, a close overt–covert mapping. We propose a framework to rehabilitate reverse inference.     

Creating Brand Meaning: A Review and Research Agenda

In this paper I review, from the perspective of experimental research, studies that have examined how brands acquire cultural meaning, and suggest future research directions. McCracken's (Journal of Consumer Research, 13 , 1986 and 71) model of the meaning transfer process gained influence about thirty years ago, but experimental studies of the processes it posited have been limited in their scope. The review is organized around three questions. First, what should be the dependent variables: the types of meanings that can adhere to brands? Second, what have we learned from studies on the types of visual, sensory, and human cues that are the sources of particular types of brand meaning—our independent variables? Third, what do we know, and need to know, about the inferential and other processes through which consumers “take possession” of these brand meanings from these cues? The review concludes with a research agenda.