The representational basis of syllable categories

Two hypotheses concerning the relation between phoneme and syllable categories are contrasted. The phonological hypothesis holds that phoneme categories are perceptually basic, whereas syllable categories are abstract and specify the phonological rules operating on phoneme categories. The integrative routine hypothesis suggests that whereas phoneme categories are basic, syllable categories are not entirely abstract but are represented at least partially on the basis of higher order perceptual information, specifying the dynamics of coarticulating phoneme categories. Three experiments used a primed naming task in which subjects had to name the entire syllable (consonant-vowel and vowel-consonant; Experiment 1), the syllable-initial phoneme category (Experiment 2), or the syllable-final phoneme category (Experiment 3). The results supported the integrative routine hypothesis. S.D. is a postdoctoral fellow of the Belgian Fund for Scientific Research.     

The conceptual grouping effect: categories matter (and named categories matter more)

Do conceptual categories affect basic visual processing? A conceptual grouping effect for familiar stimuli is reported using a visual search paradigm. Search through conceptually-homogeneous non-targets was faster and more efficient than search through conceptually-heterogeneous non-targets. This effect cannot be attributed to perceptual factors and is not explained by a long-term representational reorganization due to perceptual-learning. Rather, conceptual categories seem to modulate visual representations dynamically, and are sensitive to task-demands. Verbally labeling a visual target further exaggerates the degree to which conceptual categories penetrate visual processing.     

The generalized polymorphous concept account of graded structure in abstract categories

Abstract categories present with graded structure. The extent to which feature commonality between exemplars and category provides a satisfying account of this graded structure varies from one abstract category to the other (Hampton, 1981). We investigate whether the incorporation of features that exemplars share with external categories yields an improved account of abstract categories' graded structures. In doing so, we follow the suggestion that abstract categories are relational in nature (Goldstone, 1996; Wiemer-Hastings & Xu, 2005). The generalized polymorphous concept model, which incorporates both types of features, is found to improve the account of typicality and category membership in three of seven studied abstract categories. These three categories are found to be the most abstract, suggesting that it is appropriate to think of abstract categories as varying along a continuum of abstractness/interrelatedness rather than as a distinct type of category altogether.     

The development of conceptual categories of attention during the elementary school years

The purpose of this study was to explore the development of children's conceptual understanding of attention by focusing on their awareness of various subtypes of attention. Adults, fifth graders (mean age = 11.16 years), and third graders (9.16 years) participated in a Similarity Judgment task in which they rated the similarity of pairs of cognitive scenarios involving various attentional processes. These similarity judgments were submitted to an extended similarity tree analysis (EXTREE; J. E. Corter & A. Tversky, 1986) and the interpretations of the clusters and features that emerged were confirmed by participants in an Attribute Rating task. Three changes were found with increasing age: (1) Less emphasis was placed on the surface features of the scenarios, (2) more attentional subtypes were identified, and (3) more emphasis was placed on the role of effort in attention. We conclude that during elementary school and beyond children came to understand that intentional, effortful cognitive processes can mediate between the external world and our conscious experiences of it.     

Essentialism and graded membership in animal and artifact categories

A number of studies have argued that people view membership in animal and artifact categories as a matter of degree. These studies have generally failed to distinguish between the issues of typicality and category membership. Thus, data which have been taken to demonstrate that membership is a matter of degree may only demonstrate that typicality is graded. Partly on the basis of these findings, it has been argued that some categories are organized around an underlying essence. The essence determines membership absolutely. The present paper reports a series of studies that reexamine the question of graded membership. In the first study, subjects were asked to rate both typicality and category membership for the same stimuli as a way of distinguishing the two questions. A second method relied on the intuition that disagreements about membership in all-or-none and graded categories may have different qualities. Results from both studies suggest some support for claims that membership in animai and artifact categories is a matter of degree. A third study explored the possibility that graded responses were due to conflicting, or ambiguous, sets of criteria. A task focusing on biological features did not lead to more absolute categorization. These results contradict essentialist predictions.     

A conceptual and psychometric framework for distinguishing categories and dimensions

An important, sometimes controversial feature of all psychological phenomena is whether they are categorical or dimensional. A conceptual and psychometric framework is described for distinguishing whether the latent structure behind manifest categories (e.g., psychiatric diagnoses, attitude groups, or stages of development) is category-like or dimension-like. Being dimension-like requires (a) within-category heterogeneity and (b) between-category quantitative differences. Being category-like requires (a) within-category homogeneity and (b) between-category qualitative differences. The relation between this classification and abrupt versus smooth differences is discussed. Hybrid structures are possible. Being category-like is itself a matter of degree; the authors offer a formalized framework to determine this degree. Empirical applications to personality disorders, attitudes toward capital punishment, and stages of cognitive development illustrate the approach.     

The Shedler-Westen Assessment Procedure-200 as a basis for modifying DSM personality disorder categories

The Shedler-Westen Assessment Procedure-200 (SWAP) is a Q-sort instrument designed to assess personality pathology on the basis of clinician ratings. On the basis of research with the SWAP, its creators have proposed a group of 12 personality disorder (PD) diagnoses that can be used to replace or modify current Axis II categories of the Diagnostic and Statistical Manual of Mental Disorders (DSM). The authors discuss conceptual and empirical issues that require clarification before this proposal can be properly evaluated. They identify problematic psychometric features of the SWAP, including its unrepresentative normative sample, its reliance on a fixed skewed distribution, and anomalies in its T-score approach to diagnoses. In addition, a review of research on SWAP-based PD categories indicates that important information regarding diagnostic coverage, validity, and temporal stability is presently lacking. The authors conclude that research evidence is currently insufficient to justify the use of SWAP-based PD categories to guide revision of the DSM.     

Analysis of the conceptual structure of natural and artifactual categories in Alzheimer's disease patients

This work has two goals, the first one is to study in detail the conceptual structure of some natural and artifactual categories, by using multidimensional scaling (MDS). According to our theoretical approximation, conceptual structure is composed of semantic features, and these features have different entities and nature. As an index of relevance in mental representation of semantic categories, we took the frequency of production of semantic features on a free verbal production task. Our second goal was to compare the structure of conceptual representations in two populations, healthy elderly and Alzheimer's disease (AD) patients, assuming that conceptual representation is impaired in this last population. We assume that the impairment in the conceptual representations of AD patients will show, when the disease reaches a determined level, loosing specific features. This impairment will have serious consequences in the whole conceptual structure.     

The conceptual basis of function learning and extrapolation: Comparison of rule-based and associative-based models

The purpose of this article is to provide a foundation for a more formal, systematic, and integrative approach to function learning that parallels the existing progress in category learning. First, we note limitations of existing formal theories. Next, we develop several potential formal models of function learning, which include expansion of classic rule-based approaches and associative-based models. We specify for the first time psychologically based learning mechanisms for the rule models. We then present new, rigorous tests of these competing models that take into account order of difficulty for learning different function forms and extrapolation performance. Critically, detailed learning performance was also used to conduct the model evaluations. The results favor a hybrid model that combines associative learning of trained input—prediction pairs with a rule-based output response for extrapolation (EXAM).     

The downside of categories

One of the primary uses of categories is to draw inferences about novel objects based on their category membership. In a recent study, Lagnado and Shanks show that people make different inferences about an object depending on whether they first categorize the object at a general or specific level. Indeed, their inference changes even though they have been given no information about the object. This finding reveals limitations of category-based induction.     

Ideals, central tendency, and frequency of instantiation as determinants of graded structure in categories

Three possible determinants of graded structure (typicality) were observed in common taxonomic categories and goal-derived categories: (1) an exemplar's similarity to ideals associated with goals its category serves; (2) an exemplar's similarity to the central tendency of its category (family resemblance); and (3) an exemplar's frequency of instantiation (people's subjective estimates of how often it is encountered as a category member). Experiment 1 found that central tendency did not predict graded structure in goal-derived categories, although it did predict graded structure in common taxonomic categories. Ideals and frequency of instantiation predicted graded structure in both category types to sizeable and equal extents. A fourth possible determinant--familiarity--did not predict typicality in either common taxonomic or goal-derived categories. Experiment 2 demonstrated that both central tendency and ideals causally determine graded structure, and work showing that frequency causally determines graded structure is discussed. Experiment 2 also demonstrated that the determinants of a particular category's graded structure can change with context. Whereas ideals may determine a category's graded structure in one context, central tendency may determine a different graded structure in another. It is proposed that graded structures do not reflect invariant structures associated with categories but instead reflect people's dynamic ability to construct concepts.     

The abstraction of arbitrary categories

Bransford and Franks (1971) showed that people retain the ideas expressed in linguistic input, rather than retaining the individual sentences. The extent to which this phenomenon reflects organizational’ processes based on co-occurrence information was investigated by using Bransford and Franks’ procedure but substituting arbitrarily chosen groups of words for sentences. The subjects gave higher recognition ratings to large new groups (analogous to complex sentences) than to small new groups (analogous to simpler ones), so long as the size of the group was in the range normally presented. They also showed the same ordering for old groups; but they rated old groups higher than new groups within each group size. Hierarchical recognition response structure can be established without an ideational basis, and it does not require complete absence from memory of original input items.     

The stability of social categories

One important thesis Ásta defends in Categories We Live By is that social properties and categories are somehow dependent on our thoughts, attitudes, or practices—that they are inventions of the mind, projected onto the world. Another important aspect of her view is that the social properties are related to certain base properties; an individual is placed in a category when the relevant base properties are thought to hold of them. I see the relationship between the social and the base as connected to the problem of explaining how the social properties are sufficiently stable so as to be taken seriously, both in theoretical endeavors as well as in practical matters of how we relate to each other. In this light, I identify stability constraints for an adequate account of social categories. I argue that certain distinctive aspects of Ásta's conferralist view of social categories, such as the radical contextualism in her account of gender, undermine the stability of categories and are at odds with taking social categories seriously. I end with the suggestion that a distinctive “sheltered” form of normativity might help us do justice to Ásta's insights while avoiding some of the destabilizing elements of conferralism.     

A note on the natural basis of action categories: the catching distance of mantids

What is the basis for the categorical distinctions evident in action? For some visually-guided activities it can be shown that categories of action are specified by criterial values of optical properties. In the more general case, the criterial optical properties should be scaled relative to dimensions of the acting animal. The analysis of the prey-catching behavior of praying mantids is used to exemplify the strategy for determining naturally defined boundaries on actions.     

Case-like categories in children: The actor and some related categories

Case categories were investigated using a method in which pictures are presented accompanied by a sentence describing the scene: Preschool children learn to put tokens on the objects in the pictures according to the role each object plays in the scene as described. Generalization trials explore what the children include within the various roles. Children rapidly learn to associate tokens with case-like categories during the training phase, and readily transfer to new stimuli in generalization trials. The experiments demonstrate that children have a broad Actor category. The Actor “does” the action, and Actors are not necessarily animate. However, animacy is a class property of stimuli to which the children were very sensitive. There was evidence that User and Instrument are subcategories of Actor that are differentiated only when a sentence contains both. The data also suggest a Locative category, and Patient as a category of the grammatical object. Finally, the children appeared to treat subjects of predicate adjectives as a separate category, here called the Subject of Attribution, distinct from Actor, and functionally independent of objects of transitive verbs.     

The cognitive structure of social categories

Support for the prototype theory of categorization was found in a study of the structure of social categories. Though occupational terms such as DOCTOR are socially defined, they do not have the classical structure their clear definitional origins would predict. Conceptions of social categories are richer and more complex than those of physical object categories and subjects agree upon them. Comparison of various instructions for eliciting attributes of categories showed that whether subjects are asked to define a term, give characteristics, or describe ways they recognize members of categories, the attributes they list contribute to a prototype structure. These data provide evidence against the view that prototype structure is relevant only to an identification procedure and not to the core of concepts, as has been suggested.     

A biodynamic basis for perceived categories of action: a study of sitting and stair climbing

Actors must determine whether the properties of the surface layout are sufficient to meet their specific requirements for performing an action. Warren's (1984) study of bipedal stair climbing has demonstrated the significance of intrinsic, body-scaled measures of environmental properties for defining perceptual categories relevant to action. Whereas the absolute measure of the perceptual boundary between "climbable" and "not climbable" varied according to the actor's size and mass, the perceived boundary was a constant proportion of each actor's leg length. Our current study examined the perceived maximum seat height (SHmax) for the act of sitting. Experiment 1 delineated the range of surface heights that were perceived to afford sitting on. When expressed as a function of each person's leg length (L), SHmax was remarkably stable across individuals. Unexpectedly, it was quite close to the maximum riser height determined by Warren. Experiment 2 examined whether this similarity reflected a common biodynamic requirement, since climbing and sitting require actors to lift their center of gravity above the surface of support. Perceived critical heights were obtained for both acts using the same methods and apparatus. The perceived maximum heights for each act were virtually identical. These findings are consistent with the possibility that the information used in determining critical action boundaries is already scaled with reference to some physical dimension of the actor.