Effects of diagnostic classification systems on clinical hypothesis-generation

In this study it was determined whether (a) classification as opposed to absence of classification has an effect on the quality of clinical hypotheses (b) the DSM-III-R and the CBCL have a different effect on the quality of clinical hypotheses, and (c) the potential difference between the DSM-III-R and the CBCL is moderated by the different number of syndromes identified by these systems. To investigate these questions, an experiment was conducted in which 86 clinicians generated hypotheses for six cases. The clinicians were divided into a DSM-III-R, a CBCL, and a control group. Of the six cases, two were classified by both classification systems as one syndrome, two were classified as one syndrome by the DSM-III-R but as two syndromes by the CBCL, and two were classified as two syndromes by the DSM-III-R but as one syndrome by the CBCL. The quality of the hypotheses was determined by means of four dependent variables selected from an overview of qualitative criteria: explanatory value, redundancy, possibility of operationalization, and specificity. No differences between the CBCL and the control groups were found. The DSM group performed better than the control group regarding explanatory value and redundancy. The DSM-III-R group also scored better than the CBCL group regarding explanatory value, particularly when the number of identified syndromes was two for the CBCL and one for the DSM-III-R.     

The measurement of imagery ability

When variations in imagery ability are used to predict task performance, distinct and consistent relationships do not tend to emerge. A selective review of studies is undertaken to outline some basic reasons why individual difference measures of imagery are often so unsuccessful. Relevant studies concerning the learning and performance of motor skills are examined in some detail. It is concluded that the major problem in these studies is the types of imagery tests that have been employed; these tests have not adequately measured imagery ability. A recently developed instrument, the Movement Imagery Questionnaire, which has been designed to assess individual differences in visual and kinesthetic imagery of movement is discussed.     

Completely nonmetric multidimensional scaling

Most of the distance models underlying multidimensional scaling assume that if a stimulus y is between the stimuli x and z on each dimension, then x and z should be the farthest apart of the three stimuli. An iterative algorithm is described that uses only this betweenness prediction to infer the ordering of a set of stimuli on each of one or two dimensions. Applied to previously published semantic similarity data, this algorithm produced two-dimensional configurations that were similar in appearance to Euclidean configurations but generally involved fewer violations of the betweenness prediction.     

Parameters for vowel substitutions in Broca''s aphasia

Most phonological investigations of aphasic speech have focused on consonants. In this study, the vowel substitutions of five English-speaking Broca's aphasics were investigated with respect to several major explanatory hypotheses. An important possible motivating factor for aphasic substitutions, phonological environment, is an unlikely origin for these errors, since most substitutions occur along the paradigmatic axis. Another prominent hypothesis, markedness, also has no predictive power for the data of this sample. However, an analysis of the five Chomsky and Halle (1968, (The Sound Pattern of English), New York: Harper and Row) vowel features indicates that the two features for vowel height are selectively impaired: There is a strong tendency for lower vowels to replace higher targets. Moreover, the substitution sounds tend to be close to their target sounds along the height axis. Four possible hypotheses are advanced to account for this consistent lowering tendency.     

“Impossible figures” and interpretations of polyhedral figures

The concept “impossible figure” is analyzed by formalizing the interpretations of a polyhedral figure by an observer, and defining several types of inconsistency in such interpretations. Tests for these inconsistencies are developed using simple graph theory, and a sufficient condition is established for the feasibility of an interpretation. Finally, techniques are derived for the automatic construction of usual or unusual multibar figures.     

Pavlovian conditioned stimulus effects upon instrumental choice behavior are reinforcer specific

In a transfer-of-control experiment with rats, Pavlovian CSs were tested for the specificity of their effects. The instrumental behavior consisted of a discriminative, conditional two-lever choice task in which qualitatively different appetitive reinforcers were contingent upon the two correct choices. In a Pavlovian phase, subjects experienced conditioning to establish either a CS⁺ or CS^? for one reinforcer or a CS⁺ or CS^? for the other reinforcer. Finally, in a test, these CSs were presented when there was the opportunity to make choice responses. The CS⁺s evoked choices of the lever which had eventuated in the reinforcer that had served as the Pavlovian US, while the CS^?s showed only a slight tendency to evoke the other choice responses. When the CSs were compounded with the original S^Ds, the CS⁺s had little effect upon the vigor of responding while the CS^?s reduced the vigor of responding to the S^D for the reinforcer that was the same as the US used in establishing the CS^?. The results are discussed in terms of associative mediational theory and the reinforcer specificity of Pavlovian conditioned excitation and inhibition.     

Towards a new philosophy of education: Extending the conversational metaphor for thinking

Recently, feminists like Jane Roland-Martin, Elizabeth Young-Bruehl, and others have advocated a conversational metaphor for thinking and rationality, and our image of the rational person. Elizabeth Young-Bruehl refers to thinking as a constant interconnecting of representations of experiences and an extension of how we hear ourselves and others. There are numerous disadvantages to thinking about thinking as a conversation.We think there are difficulties in accepting the current formulation of the conversational metaphor without question. First, there is danger that we will lose important dialectical connections like that between the self and society. Second, the conversational metaphor alone cannot fully express the way conversations are constructed. We will want to take up the notion of narrative as a metaphor for thinking advocated by Susan Bordo, Alasdair MacIntyre, Jerome Bruner, and others, including Mary Belenky and her colleagues.Eventually, we want to champion narrative and the dramatic narrative of culture as a metaphor for thinking that involves such expressions as sights, insights, silences, as well as sounds, moments of mood and poetic moments. The dramatic narrative provides the structural possibilities needed to criticize certain kinds of conversations, in order to talk about the relations of public and private, self and society and most importantly, about the drama of our lives within and without.The dramatic narrative for thinking helps dispel the dangerous dualisms of mind and body that not even conversation or narration alone can banish, and allows us to frame questions about education that do not require us to separate mind from body. The dramatic narrative metaphor for thinking lets us show who we are, act out what we think, and reconstruct rationality to reflect what many women, and some men, do.     

Affective and cognitive mediators of reactions to spatial invasions

At a crosswalk on a busy street, a confederate, sketching a drawing or not, stood close or far from a pedestrian for 10 sec before the street light indicated “Walk.” In the first study, pedestrians were given the opportunity to subsequently help this confederate or another accomplice by calling attention to a dropped pen. In the second study, crossing speeds were timed and pedestrians were asked to record their mood and reactions to “another pedestrian,” who happened to be the confederate. These studies tested and found evidence for both cognitive and arousal explanations of reactions to spatial invasions. Cognitive and attributional theories imply that characteristics of the invader are important mediators of reactions to the invasion. The close nonartist was judged to be more inappropriate, produced faster escape speeds, and was helped less than the close artist or the far confederates. Arousal explanations imply that any invasion produces a generalized reaction which would be unrelated to characteristics of the invader. The other accomplice was helped less when the subject had been invaded and this reduction in helping was unaffected by the artist manipulation. These findings suggest a general arousal response to any invasion with a subsequent reliance on cognitive interpretations.