Mimicry for money: Behavioral consequences of imitation

Two experiments investigated the idea that mimicry leads to pro-social behavior. It was hypothesized that mimicking the verbal behavior of customers would increase the size of tips. In Experiment 1, a waitress either mimicked half her customers by literally repeating their order or did not mimic her customers. It was found that she received significantly larger tips when she mimicked her customers than when she did not. In Experiment 2, in addition to a mimicry- and non-mimicry condition, a baseline condition was included in which the average tip was assessed prior to the experiment. The results indicated that, compared to the baseline, mimicry leads to larger tips. These results demonstrate that mimicry can be advantageous for the imitator because it can make people more generous.     

Grasp preparation improves change detection for congruent objects

A series of experiments provided converging support for the hypothesis that action preparation biases selective attention to action-congruent object features. When visual transients are masked in so-called change-blindness scenes, viewers are blind to substantial changes between 2 otherwise identical pictures that flick back and forth. The authors report data in which participants planned a grasp prior to the onset of a change-blindness scene in which 1 of 12 objects changed identity. Change blindness was substantially reduced for grasp-congruent objects (e.g., planning a whole-hand grasp reduced change blindness to a changing apple). A series of follow-up experiments ruled out an alternative explanation that this reduction had resulted from a labeling or strategizing of responses and provided converging support that the effect genuinely arose from grasp planning.     

Asymmetrical learning between a tactile and visual serial RT task

According to many researchers, implicit learning in the serial reaction-time task is predominantly motor based and therefore should be independent of stimulus modality. Previous research on the task, however, has focused almost completely on the visual domain. Here we investigated sequence learning when the imperative stimuli were presented tactilely to the fingers. Learning in this task was compared to sequence learning in a typical visual task, using very similar experimental conditions. The results indicate that sequential learning occurs in the tactile task, though to a lesser degree than in its visual counterpart. Furthermore, there was similar cross-modal transfer in both directions, meaning that transfer from the visual to the tactile task was partial. It is proposed that sequence learning involves a stimulus-specific component in the visual but not in the tactile task.     

The Medical Humanities Today: Humane Health Care or Tool of Governance?

The medical humanities have been presented as a panacea for medical reductionism; a means for 'humanizing' medicine. However, there is a lack of consensus about the appropriate contributing disciplines and how curricula should be taught and assessed. This special issue critically examines the role of the medical humanities in medical education and their potential to serve, inadvertently or otherwise, as a tool of governance. The contributors, who include medical educators and medical practitioners, employ a range of perspectives for analysing the pertinent issues.     

The electronic mood device: Design, construction, and application

The electronic mood device (EMD) is designed to help answer questions about the variability and dynamics of emotions. It is a small, portable instrument used for repeated recording of moods and feelings. Both construction and operation of the EMD are described. The EMD can best be conceived of as an electronic mood adjective checklist. Persons using the EMD are signaled at designated (e.g., hourly) or random intervals to register their mood or feelings. Paper and pencil are not required. An application is given. It shows how feelings vary within and between persons and during the day. It is concluded that the EMD offers several advantages over paper-and-pencil instruments. Retrospective use is impossible. Timing and registration are accurate. Data handling is fast. Potential future applications are suggested.     

Beliefs and data on the relationship between consistency and accuracy of eyewitness testimony

Two studies concerned with consistency and accuracy of eyewitness testimony were conducted. In Study 1 potential jurors indicated the degree to which they considered that various witness on‐stand behaviours indicated testimonial accuracy. Witness statements that were inconsistent with previous statements were considered to be the strongest indicators of inaccuracy. Study 2 examined the relationship between consistency and accuracy of testimony. Witnesses viewed a film of a robbery and were interviewed twice (2 weeks apart) about the crime in a 4 (interview format)×2 (interview occasion) design. Regardless of whether consistency was operationalised in terms of direct contradictions between interviews, or degree of agreement on detail across interviews, no more than 10% of the variance in overall accuracy rate was explained by any individual measure. Number of contradictions and overall agreement between interviews did, however, make additive contributions to prediction of overall accuracy. Also, higher correlations between contradiction‐based consistency measures and interview two accuracy rate were detected. Neither consistency nor accuracy for specific testimonial dimensions were predictive of accuracy on the other dimensions, or overall accuracy. Copyright © 1999 John Wiley & Sons, Ltd.     

Precision and power grip priming by observed grasping

The coupling of hand grasping stimuli and the subsequent grasp execution was explored in normal participants. Participants were asked to respond with their right- or left-hand to the accuracy of an observed (dynamic) grasp while they were holding precision or power grasp response devices in their hands (e.g., precision device/right-hand; power device/left-hand). The observed hand was making either accurate or inaccurate precision or power grasps and participants signalled the accuracy of the observed grip by making one or other response depending on instructions. Responses were made faster when they matched the observed grip type. The two grasp types differed in their sensitivity to the end-state (i.e., accuracy) of the observed grip. The end-state influenced the power grasp congruency effect more than the precision grasp effect when the observed hand was performing the grasp without any goal object (Experiments 1 and 2). However, the end-state also influenced the precision grip congruency effect (Experiment 3) when the action was object-directed. The data are interpreted as behavioural evidence of the automatic imitation coding of the observed actions. The study suggests that, in goal-oriented imitation coding, the context of an action (e.g., being object-directed) is more important factor in coding precision grips than power grips.     

Individual differences in learning to perceive length by dynamic touch: Evidence for variation in perceptual learning capacities

Recent studies of perceptual learning have explored and commented on variation in learning trajectories. Although several factors have been suggested to account for this variation, thus far the idea that humans vary in their perceptual learning capacities has received scant attention. In the present experiment, we aimed at providing a detailed picture of the variation in this capacity by investigating the perceptual learning trajectories of a considerable number of participants. The learning process was studied using the paradigm of length perception by dynamic touch. The results showed that there are substantial individual differences in the way perceivers respond to feedback. Indeed, after feedback, the participants' perceptual performances diverged. We conclude that humans vary in their perceptual learning capacities. The implications of this finding for recent discussions on variation in perception are explored.     

A bottleneck in face identification: repetition priming from flanker images

There is evidence that face processing is capacity-limited in distractor interference tasks and in tasks requiring overt recognition memory. We examined whether capacity limits for faces can be observed with a more sensitive measure of visual processing, by measuring repetition priming of flanker faces that were presented alongside a face or a nonface target. In Experiment 1, we found identity priming for face flankers, by measuring repetition priming across a change in image, during task-relevant nonface processing, but not during the processing of a concurrently-presented face target. Experiment 2 showed perceptual priming of the flanker faces, across identical images at prime and test, when they were presented alongside a face target. In a third Experiment, all of these effects were replicated by measuring identity priming and perceptual priming within the same task. Overall, these results imply that face processing is capacity limited, such that only a single face can be identified at one time. Merely attending to a target face appears sufficient to trigger these capacity limits, thereby extinguishing identification of a second face in the display, although our results demonstrate that the additional face remains at least subject to superficial image processing.