Can expertise modulate representational momentum?

Representational momentum (RM) refers to the tendency of participants to “remember” the stopping point of an event as being farther along in the direction of movement than it was in reality (Freyd & Finke, 1984). Our aim was twofold: (1) Test for the impact of domain-specific expertise (here, automobile driving) on RM, using films of road scenes, and (2) find out whether the improved anticipation ability that comes with greater expertise is transferred to scenes from domains that are far-removed from the person's domain of expertise. Two experiments were conducted in which experienced and inexperienced automobile drivers performed a movement-anticipation task on realistic road scenes (Experiment 1), with stimuli that were very different from those found in their domain of expertise (Experiment 2). These studies pointed out some properties of representational momentum, and showed that RM is dependent upon knowledge acquired by participants in specific domains. Our research also showed that expertise in automobile driving can modulate RM in road-scene perception (i.e., the cognitive characteristics of the observer can modulate the magnitude of the RM effect) but that expertise in automobile driving is not transferred to dissimilar domains.     

Measuring causal perception: connections to representational momentum?

In a collision between two objects, we can perceive not only low-level properties, such as color and motion, but also the seemingly high-level property of causality. It has proven difficult, however, to measure causal perception in a quantitatively rigorous way which goes beyond perceptual reports. Here we focus on the possibility of measuring perceived causality using the phenomenon of representational momentum (RM). Recent studies suggest a relationship between causal perception and RM, based on the fact that RM appears to be attenuated for causally 'launched' objects. This is explained by appeal to the visual expectation that a 'launched' object is inert and thus should eventually cease its movement after a collision, without a source of self-propulsion. We first replicated these demonstrations, and then evaluated this alleged connection by exploring RM for different types of displays, including the contrast between causal launching and non-causal 'passing'. These experiments suggest that the RM-attenuation effect is not a pure measure of causal perception, but rather may reflect lower-level spatiotemporal correlates of only some causal displays. We conclude by discussing the strengths and pitfalls of various methods of measuring causal perception.     

The professionalism movement: can we pause?

The topic of developing professionalism dominated the content of many academic medicine publications and conference agendas during the past decade. Calls to address the development of professionalism among medical students and residents have come from professional societies, accrediting agencies, and a host of educators in the biomedical sciences. The language of the professionalism movement is now a given among those in academic medicine. We raise serious concerns about the professionalism discourse and how the specialized language of academic medicine disciplines has defined, organized, contained, and made seemingly immutable a group of attitudes, values, and behaviors subsumed under the label of "professionalism." In particular, we argue that the professionalism discourse needs to pay more attention to the academic environment in which students are educated, that it should articulate specific positive behaviors, that the theory of professionalism must be constructed from a dialogue with those we are educating, and that this theoretical and practical discourse must aim at a deeper understanding of social justice and the role of medicine within a just society.     

Are boundary extension and representational momentum related?

Boundary extension (BE) is misremembering more of a particular scene than actually presented. Representational momentum (RM) is misremembering the final position of a moving object as further along its implied trajectory. There is a sense in which both BE and RM are predictions, and the current experiments explore the possibility that these are related phenomena. We showed participants single photographs to measure baseline BE, and then approach sequences and measured BE and RM. We found significant BE and RM, and a significant interaction between baseline BE and BE following an approach sequence, but no interaction with RM. The initial evidence suggests that BE and RM are separate processes, and that BE (the establishing of spatial layout) occurs before RM (the continuation of movement) within a scene.     

The role of attention in the affordance effect: can we afford to ignore it?

It has been established that the task-irrelevant orientation of an object's graspable handle produces a stimulus-response compatibility effect, resulting in faster reaction times when the location of the response corresponds to that of the object's handle. There is ongoing debate whether to attribute this affordance effect to motoric or to attentional components. In an attempt to reconcile these two viewpoints, we employed a novel experimental approach for investigating the relationship between attention and affordance. Using 3-D positional sound, auditory spatial attention was manipulated in order to explore its effects on affordance. Subjects were presented images of everyday graspable objects and had to respond bimanually (left or right) whether the object (featuring a leftward or rightward handle) was presented upright or upside-down. Prior to each affording object, sound localization cues were manipulated so as to orient auditory attention to the left, or to the right of the interaural axis (control). We obtained a peculiar pattern of results, which not only appears to provide support for an attention-shift account of affordance but does so in a cross-modal context.     

Juvenile homicide in America: how can we stop the killing?

Juvenile homicide remains a serious problem in the U.S., despite recent decreases in the juvenile arresr rate for murder. Reflecting on her clinical experiences evaluating 90 adolescent murderers, the author identifies 15 factors that appear to have contributed to the escalation in juvenile homicide beginning in the mid-198os. These factors can be grouped into five categories: situational factors (child abuse and neglect, and the absence of positive male role models), societal influences (the crisis in leadership and lack of heroes, and witnessing violence), resource availability (access to guns, involvement in alcohol and drugs, and poverty and lack of resources), personality characteristics (low self-esteem, the inability to deal with strong feelings, boredom, poor judgement, and prejuduce and hatred), and their cumulative effects (little or nothing to lose and the biological connection). Strategies to reduce juvenile violence are addressing using parents, schools, communities, government leaders, the media and individuals. ©1997 John Wiley & Sons, Ltd.     

Epistemic issues in the free will debate: can we know when we are free?

In this paper, I argue that the views of Robert Kane on the one hand and John Fischer and Mark Ravizza on the other both lead to the following conclusion: we should have very low confidence in our ability to judge that someone is acting freely or in a way for which they can be held responsible. This in turn means, I claim, that these views, in practice, collapse into a sort of hard incompatibilist position, or the position of a free will denier. That would at least be an unintended consequence, and it might be regarded as a virtual reductio. Versions of the objection could likely be made against a number of other accounts of free will, but I will limit my focus to Kane and Fischer. Along the way, by way of response to some possible objections to my argument, I make some comments about epistemic closure principles.     

Comparing mislocalizations with moving stimuli: The Fröhlich effect,the flash-lag,and representational momentum

When observers are asked to localize the onset or the offset position of a moving target, they typically make localization errors in the direction of movement. Similarly, when observers judge a moving target that is presented in alignment with a flash, the target appears to lead the flash. These errors are known as the Fröhlich effect, representational momentum, and flash-lag effect, respectively. This study compared the size of the three mislocalization errors. In Experiment 1, a flash appeared either simultaneously with the onset, the mid-position, or the offset of the moving target. Observers then judged the position where the moving target was located when the flash appeared. Experiments 2 and 3 are exclusively concerned with localizing the onset and the offset of the moving target. When observers localized the position with respect to the point in time when the flash was presented, a clear mislocalization in the direction of movement was observed at the initial position and the mid-position. In contrast, a mislocalization opposite to movement direction occurred at the final position. When observers were asked to ignore the flash (or when no flash was presented at all), a reduced error (or no error) was observed at the initial position and only a minor error in the direction of the movement occurred at the final position. An integrative model is proposed, which suggests a common underlying mechanism, but emphasizes the specific processing components of the Fröhlich effect, flash-lag effect, and representational momentum.     

Does representational momentum reflect a distortion of the length or the endpoint of a trajectory?

Observers viewed a moving target, and after the target vanished, indicated either the initial position or the final position of the target. In Experiment 1, an auditory tone cued observers to indicate either the initial position or the final position; in Experiment 2, different groups of observers indicated the initial position or the final position. Judgments of the initial position were displaced backward in the direction opposite to motion, and judgments of the final position were displaced forward in the direction of motion. The data suggest that the remembered trajectory is longer than the actual trajectory, and the displacement pattern is not consistent with the hypothesis that representational momentum results from a distortion of memory for the location of a trajectory.     

The drawbridge phenomenon: representational reasoning or perceptual preference?

Two experiments investigated whether infants would look longer at a rotating "drawbridge" that appeared to violate physical laws because they knew that it was causally impossible, as claimed by R. Baillargeon, E. S. Spelke, and S. Wasserman (1985) and R. Baillargeon (1987a). Using a habituation paradigm, they reported that infants looked longer at a display that appeared impossible (rotated 180 degrees while an obstructing box was behind it) than at one that appeared possible (rotated only 112 degrees, appearing to stop at the box). Experiment 1 eliminated habituation to 180 degree screen rotations. Still, infants looked longer at the 180 degree impossible rotations. Critically, however, infants also looked longer at possible 180 degree rotations in Experiment 2, in which no obstruction was present. Moreover, no difference in effect size was found between the 2 experiments. These findings indicate that infants' longer looking at 180 degree rotations is due to simple perceptual preference for more motion. They question R. Baillargeon's (1987a) claim that it is due to infants' representational reasoning about physically impossible object permanence events.     

How can we tell the Dancer from the Dance?: The Subject of Dance and the Subject of Philosophy

One of the most important aspects of Gilles Deleuzes philosophy is his criticism of the traditional concept of praxis. In Aristotelian philosophy praxis is properly oriented towards some end, and in the case of human action the ends of praxis are oriented towards the agents good life. Human goods are, for both Aristotle and contemporary neo-Aristotelians, determined by the potentials of human life such as rationality, communality, and speech. Deleuzes account of action, by contrast, liberates movement from an external end. In his books on cinema Deleuze argues that we need to think of events in terms of their power, and not as movements within an already determined image of life. In order to think events as such we need to confront the power of the virtual. This is achieved by a philosophy of life in which becoming is not a means towards the realisation of some end. Rather, becomings are best seen as counter-actualisations: ways in which the already-constituted actual world always bears a power to become other than it already is. If we consider dance in this new context, then dance is neither expressive of an already existing life, nor a pure act that is self-sufficient and self-constituting. Rather, dance is a confrontation with life as a plane of open and divergent becomings.     

When can we trust theF-approximation of the box-test?

Consider a multivariate context withp variates andk independent samples, each of sizen. To test equality of thek population covariance matrices, the likelihood ratio test is commonly employed. Box'sF-approximation to the null distribution of the test statistic can be used to computep-values, if sample sizes are not too small. It is suggested to regard theF-approximation as accurate if the sample sizesn are greater than or equal to 1+0.0613p ²+2.7265p-1.4182p ^0.5+0.235p ^1.4* In (k), for 5p30,k20.This research was supported by the Deutsche Forschungsgemeinschaft through Ste 405/2-1.     

Modelling vagueness: what can we ignore?

A theory of vagueness gives a model of vague language and of reasoning within the language. Among the models that have been offered are Degree Theorists?? numerical models that assign values between 0 and 1 to sentences, rather than simply modelling sentences as true or false. In this paper, I ask whether we can benefit from employing a rich, well-understood numerical framework, while ignoring those aspects of it that impute a level of mathematical precision that is not present in the modelled phenomenon of vagueness. Can we ignore apparent implications for the phenomena by pointing out that it is ??just a model?? and that the unwanted features are mere artefacts? I explore the distinction between representors and artefacts and criticise the strategy of appealing to features as mere artefacts in defence of a theory. I focus largely on theories using numerical resources, but also consider other, related theories and strategies, including theories appealing to non-linear structures.     

The Spiritual,the Cultural and the Religious: What can we learn from a study of boy choristers?

This article reports on a study of the boys in a major city centre church choir. It is treated as a case study of the potential confusion between the spiritual, the cultural and the religious. The study shows that the performance of religious rituals might, for many of the boys, be more accurately described as a cultural phenomenon. A deep appreciation of music, with evidence of 'peak experiences', describes a reality which has been called 'spiritual' in humanistic phenomenological writings. All the boys in the study were found to be 'spiritual' in that they loved and were moved by the music they sang in church, but few perceived their singing as a form of religious ministry. Religious commitment and faith development was found to range from piety to atheism, with an increasing tendency towards Enlightenment scepticism amongst the older boys. The boys could be identified as a social group by their shared love for music, but not by a shared religious faith. Discussion is developed about the reality of the spiritual with and without a religious commitment, in which credal literalism is seen as cultural rather than spiritual. A call for greater recognition of the significance of the cultural and social is made.