Making features similar: comparison processes affect perception

In this paper, the constructive nature of comparison processes (both similarity- and differenceoriented judgments) is examined through their effects on visual perception. Previous research has shown that comparison processes enhance the tendency to interpret ambiguous objects in the light of the unambiguous objects with which they are compared (Medin, Goldstone, & Gentner, 1993). In the present paper, it is argued that comparison processes affect not only the interpretation of objects, but also their perception. In addition, it is argued that the perceptual effects of similarity-oriented comparison processes differ from those of difference-oriented comparison processes. Accordingly, it is demonstrated that when estimation of an object’s size is preceded by similarity-oriented comparisons, the Ebbinghaus illusion practically disappears, whereas prior difference-oriented comparisons tend to enhance the illusion.     

The circumplex structure of interpersonal sensitivities

Previous research on aversive interpersonal behavior has provided limited links between interpersonal sensitivities and comprehensive models of personality and social behavior. Study 1 (N = 1,336) of this article demonstrated that interpersonal sensitivities can be mapped onto the interpersonal circumplex and that people generally find others' behavior that is least similar to their own generally most aversive. In Study 2 (N = 299), a broader array of correlates with interpersonal sensitivities was investigated, and results again suggested that interpersonal opposites are generally perceived as most aversive. Study 3 (N = 315) specified romantic, platonic, or nonclose relationships and again found this pattern. Conceptualizing sensitivities with the interpersonal circumplex model permits investigators to distinguish general from specific kinds of sensitivity, allows for tests of the convergent and discriminant validity of interpersonal sensitivities, and integrates sensitivities into a well-established nomological net composed of multiple constructs relevant to social behavior and interpersonal dysfunction.     

Paired comparison experiments involving all possible pairs

The analysis of paired comparison experiments using the tie and order model due to Davidson & Beaver is extended to account for the inclusion of pairs of identical items in the experiment (design 1). It is shown that in testing for order effects, the asymptotic relative efficiency of design 1 to design 2, which includes the distinct ordered pairs, is always greater than one in non-trivial cases.     

Aesthetic appreciation of experiments: The case of 18th-century mimetic experiments

This article analyzes a type of experiment, very popular in 18th-century natural philosophy, which has apparently not led to insights into nature but which was aesthetically especially attractive. These experiments--"mimetic experiments"--allow us to trace a connection between aesthetic appreciation in science and in art contemporaneous with the science. I use this case as a problem for McAllister's theory of aesthetic induction according to which aesthetic standards in science tend to be associated with empirical success and propose an alternative mechanism that is able to account for the natural philosophers' predilection for unsuccessful but beautiful experiments.     

Models for multivariate paired comparison experiments with ties

Three models for multivariate paired comparison experiments are developed using the Farlie-Gumbel-Morgenstern approach to constructing multivariate distributions. Model 3 is a direct extension of the multivariate paired comparison model with no ties due to Davidson and Bradley.     

Native-language sensitivities: evolution in the first year of life

In the first few months of their lives, human infants can perceive differences in phonetic contrasts not present in their environment and that their parents cannot discriminate. At 12 months, their pattern of discrimination approaches that of their parents. Until recently, it was believed that the perception of native-language categories did not significantly evolve in that period. Kuhl et al. offer compelling new evidence indicating significant increase in native-language perception.     

A comparison of neuronal reactions during classical and instrumental conditioning under similar conditions

During the elaboration of an instrumental reflex, it is not obligatory to use a conditioned stimulus, which signals the necessity to generate an instrumental reaction in order to receive reinforcement. However, the presence of a conditioned stimulus simplifies analysis of instrumental reaction, which in this case is the response to the conditioned stimulus. On the other hand, it is necessary to distinguish between instrumental and classical conditioning, since in both cases the response to a conditioned stimulus increases. We studied neuronal analogs of classical and instrumental conditioning in the identified neurons responsible for the defensive closure of the pneumostome in the Helix mollusk under the same conditions. During classical conditioning, a mollusk received punishment after a tactile stimulus. During instrumental conditioning, a mollusk received punishment when an identified neuron did not generate an action potential in response to a tactile stimulus. The appearance of a painful stimulus did not depend on the generation or failure of a spike in the related control neuron. Another tactile stimulus, which was never paired with an unconditioned stimulus, was used as a discriminated stimulus. We also compared the behavior of such identified neurons during pseudoconditioning. The experiments were carried out in a semi-intact preparation. We examined how responses to the tactile and painful stimuli changed during different forms of training. It was shown that the dynamics of neuronal responses to a conditioned tactile stimulus were much more complex during instrumental conditioning and consisted of several phases. Throughout a learning session, neural system consecutively acquired information as to which kind of learning was presented, whether a reaction of the neural system must be generated or inhibited and which instrumental reaction is correct. We have demonstrated that response to a painful stimulus during classical conditioning decreases after short-term initial increase. However, during instrumental learning, the neurons controlling instrumental action remained highly sensitive to the unconditioned stimulus. Meanwhile, foreign neurons decreased their responses to the unconditioned stimulus. We may tentatively conclude that classical and instrumental paradigms are fundamentally different at the cellular level.     

Both sides get the point: Hemispheric sensitivities to sentential constraint

Behavioral studies have consistently reported striking differences in the impact of sentence-level information on the processing of words presented in the right (RVF) versus the left (LVF) visual field, with context effects apparent only for RVF items. The consistent lack of such effects in the LVF has been taken to mean that right hemisphere language comprehension is largely insensitive to message-level meaning. We used the functional specificity afforded by event-related potential measures to assess this claim. Target words completing strongly and weakly constraining sentence contexts, in which constraint arose at the sentence level rather than from lexical associations, were presented laterally in the LVF or RVF. Increased constraint significantly reduced N400 amplitudes with presentation in both VFs, with no differences in the timing or amplitude of these effects. These results are inconsistent with the view that the VF asymmetries found in behavioral measures reflect differential hemispheric capacities at the level of semantic analysis and integration, although VF-based differences on earlier components (P2) suggest asymmetries in the impact of sentential context on perceptual aspects of word processing in the two hemispheres.     

Variable-image videoconfrontation as a method of assessing body image: a technical report and comparison with similar techniques

In this study a new modified videosystem, designed for measuring body-image, was evaluated alongside the major size-estimation measure, namely, the visual size-estimation apparatus. The advantages afforded by a videosystem which allows independent adjustment of size and height/width proportions were highlighted, and its validity and reliability were examined, based on estimates made by obese, normal weight, and pregnant groups.     

Different and similar at the same time: when the activation of dissimilarity makes people look more similar

Whether two people are presented as similar or different may have a strong impact on the outcome of their comparison. In the present research, we examined the counterintuitive hypothesis that activating dissimilarity increases the perception of similarities between people, in other words increases perceived feature overlap, during the comparison process. We investigated this prediction by asking people to judge the perceived similarity between two faces with a suboptimally related or unrelated morph inserted in between (to influence joint categorization), and with similar or different facial expressions (to vary the salience of similar or different features). The results confirmed our expectations: In the similarity (joint categorization) condition, two faces that differed in expression were perceived as more dissimilar than faces with the same expression. More important for our prediction, in the dissimilarity condition two faces with different expressions were no longer perceived as more dissimilar than two faces with the same expression. We discuss implications of these findings for the mechanisms underlying comparisons between people. Copyright © 2007 John Wiley & Sons, Ltd.     

The basis of the primacy effect: Some experiments with running memory

Five experiments using the “running memory span” (RMS) technique are reported, in which subjects attempt to recall a specified number of items from the end of long sequences of digits, presented at a rate of 2/s. In Experiments I-III critical lists are included in the series which are exactly equal in length to the specified recall series. Despite the RMS set, these critical lists exhibit (I) marked primacy effects, and (2) an impairment in recall of terminal items (a “rebound effect”), compared to the baseline RMS performance. The rebound effect occurs (Experiments IV and V) even when recall of earlier items is not required. These two phenomena are robust: they occur in different experiments in which, rehearsal patterns, report order, expectancies and retrieval load are controlled. The results suggest an origin for primacy which is of a perceptual (i.e. pre-storage) nature, and that selective rehearsal is not a necessary condition for the effect to occur. A possible role of habituation of the orienting response in this phenomenon is discussed.     

Anxiety sensitivity within the anxiety disorders: disorder-specific sensitivities and depression comorbidity

The tendency to perceive anxious states as aversive and harmful is hypothesized to confer vulnerability to the development of anxiety disorders. The most commonly used measure of anxiety sensitivity, the Anxiety Sensitivity Index [ASI; Reiss, S., Peterson, R.A., Gursky, D.M., & McNally R.J. (1986). Anxiety sensitivity, anxiety frequency, and the prediction of fearfulness. Behavior Research and Therapy, 24, 1-8], is composed of multiple lower-order factors, assessing fear of physical symptoms, fear of publicly observable anxious symptoms, and fear of cognitive dyscontrol. This study examined the convergent validity of the lower-order anxiety sensitivity dimensions in DSM-IV diagnosed anxiety disorders. Participants with primary diagnoses of panic disorder with agoraphobia, social phobia, and generalized anxiety disorder (GAD) completed the ASI and measures of anxiety and depression severity. Support was found for the convergent validity of all ASI dimensions in reference to thematically related anxiety disorders and in the identification of patients presenting with and without secondary major depressive disorder (MDD). The ASI-fear of cognitive dyscontrol dimension displayed strong and nonredundant associations with GAD, dimensional depression scores, and secondary diagnoses of MDD. The conceptual implications of the shared importance of fear of cognitive dyscontrol in GAD and MDD are discussed.     

Paired comparison scaling of reaction potential in two different experiments on habituation

Thurstone’s method of paired comparisons was employed to obtain scaled values of reaction potential from two completely different experimental situations involving response decrement. The first was one in which the GSR was measured on 10 repeated presentations of a visual stimulus (N= 89). The second involved 80 presentations of ordinary visual scenes; the S looked at each scene as long as he wished before switching to the next (i.e., looking time was measured. N=80). Scaling reaction potential by Thurstone’s method provided a common operational definition for both sets of data and permitted their direct comparison in identical units. Both measures showed substantial decrement in reaction potential across stages, with the GSR scale values dropping steeply from the first to the second trial and. thereafter, following a course of decline similar to the looking time scale values. Tlie correlation of the two sets of scale values was essentially linear and equalled 0.90.     

The spectral sensitivities of the middle- and long-wavelength cones: an extension of the two-colour threshold technique of W S Stiles

When a tiny centred test flash is presented on a small concentric background, the threshold rises with background radiance more quickly than Weber's law would predict. It is argued that under such conditions it is possible, by means of a test sensitivity method, to isolate either the M-cone or the L-cone types throughout the visible spectrum. As predicted, double-branched M- and L-cone tyr functions are found when the test flash and the field are of the same wavelength. From the independent vertical displacements of the two branches as test wavelength is varied, it is possible to derive spectral sensitivities that agree well with dichromatic sensitivities and K?nig fundamentals. The test sensitivities deviate from pi 4 at longer wavelengths and from pi 5 at shorter wavelengths.     

The logic of thought experiments

In this paper I argue that (at least many) philosophical thought experiments are unreliable. But I argue that this notion of unreliability has to be understood relative to the goal of thought experiments as knowledge producing. And relative to that goal many thought experiments in science are just as unreliable. But in fact thought experiments in science play a varied role and I will suggest that knowledge production is a goal only under quite limited circumstances. I defend the view that these circumstances can (sometimes) arise in philosophy as well.