Categorization of visual stimuli in the honeybee Apis mellifera

Categorization refers to the classification of perceptual input into defined functional groups. We present and discuss evidence suggesting that stimulus categorization can also be found in an invertebrate, the honeybee Apis mellifera, thus underlining the generality across species of this cognitive process. Honeybees show positive transfer of appropriate responding from a trained to a novel set of visual stimuli. Such a transfer was demonstrated for specific isolated features such as symmetry or orientation, but also for assemblies (layouts) of features. Although transfer from training to novel stimuli can be achieved by stimulus generalization of the training stimuli, most of these transfer tests involved clearly distinguishable stimuli for which generalization would be reduced. Though in most cases specific experimental controls such as stimulus balance and discriminability are still required, it seems appropriate to characterize the performance of honeybees as reflecting categorization. Further experiments should address the issue of which categorization theory accounts better for the visual performances of honeybees.This contribution is part of the special issue “Animal Logics” (Watanabe and Huber 2006).     

The development of language and abstract concepts: the case of natural number

What are the origins of abstract concepts such as "seven," and what role does language play in their development? These experiments probed the natural number words and concepts of 3-year-old children who can recite number words to ten but who can comprehend only one or two. Children correctly judged that a set labeled eight retains this label if it is unchanged, that it is not also four, and that eight is more than two. In contrast, children failed to judge that a set of 8 objects is better labeled by eight than by four, that eight is more than four, that eight continues to apply to a set whose members are rearranged, or that eight ceases to apply if the set is increased by 1, doubled, or halved. The latter errors contrast with children's correct application of words for the smallest numbers. These findings suggest that children interpret number words by relating them to 2 distinct preverbal systems that capture only limited numerical information. Children construct the system of abstract, natural number concepts from these foundations.     

Analogical reasoning with novel concepts: Differential attention of intellectually gifted and nongifted children to relevant and irrelevant novel stimuli

Intellectually gifted and nongifted students in grades 6, 7, and 8 were given a modified verbal analogies test in which typical verbal analogy problems were preceded by novel or familiar statements about one of the analogy terms. The test required subjects to integrate this new information into an otherwise familiar problem-solving task. Both gifted and nongifted students gave significantly more attention to novel information than to familiar information. Gifted students gave significantly less attention to irrelevant novel information than did nongifted students, but did not differ from nongifted students in their attention to relevant novel information. Whereas intellectually gifted students gave significantly more time to relevant than to irrelevant novel information, non-gifted students allocated as much time to irrelevant novel information as they did to relevant novel information. Performance on this task was significantly correlated with teachers' ratings of intellectual ability for gifted, but not for nongifted students.     

Categorization of two-dimensional and three-dimensional stimuli by 18-month-old infants

In two experiments, 18-month-old infants’ categorization of 3D replicas and 2D photographs of the same animals and vehicles were compared to explore infants’ flexibility in categorization across different object representations. Using a sequential touching procedure, infants completed one superordinate and two basic-level categorization tasks with 3D replicas, 2D cut out photographs, or 2D images on photo cubes (“2D cubes”). For superordinate sets, 3D replicas elicited longer mean run lengths than 2D cut outs, and 3D replicas elicited equivalent mean run lengths as 2D cubes. For basic-level sets, infants categorized high-contrast animal sets when presented with 3D replicas, but they failed to categorize any of the 2D photograph sets. Categorization processes appear to differ for 3D and 2D stimuli, and infants’ discovery of object properties over time while manipulating objects may facilitate categorization, as least at the superordinate level. These findings are discussed in the context of infants’ representation abilities and the integration of perception and action.     

Disjunction of natural concepts

Two experiments investigated the way in which the rated membership of items in disjunctively defined categories, such as FRUITS OR VEGETABLES and PETS OR FARMYARD ANIMALS, varies as a function of membership in individual constituent categories. Items were rated for category membership and typicality in each category separately, and in their disjunction. The results showed non-Boolean effects of both overextension and underextension of the disjunctions. Typicality in the disjunction was highly predictable from constituent typicality values, using regression equations with negative interaction terms. The results are compared with similar effects for concept conjunctions and are discussed in terms of an intensional model of conceptual combination (Hampton, 1987b, 1988).     

The effect of thalamic stimulation in processing of verbal stimuli in dichotic listening tasks: a case study

In dichotic listening tasks, the (dominant) right ear's superiority in processing verbal stimuli has been attributed to its direct anatomic connection with the left dominant hemisphere. The role played by extralinguistic factors, such as attention and functional tuning of the associated cortical structures, has not been carefully examined. This investigation was undertaken to evaluate the effects of the left thalamic electric stimulation on the processing (recognition and recall) of dichotically presented CVC verbal stimuli in a patient being treated for chronic pain. We report the positive effects of electric stimulation (confirmed by increased subcortical metabolic activity using SPECT, a brain imaging technique) on the processing of dichotically presented verbal stimuli.     

Incomplete understanding of complex numbers Girolamo Cardano: a case study in the acquisition of mathematical concepts

In this paper, I present the case of the discovery of complex numbers by Girolamo Cardano. Cardano acquires the concepts of (specific) complex numbers, complex addition, and complex multiplication. His understanding of these concepts is incomplete. I show that his acquisition of these concepts cannot be explained on the basis of Christopher Peacocke’s Conceptual Role Theory of concept possession. I argue that Strong Conceptual Role Theories that are committed to specifying a set of transitions that is both necessary and sufficient for possession of mathematical concepts will always face counterexamples of the kind illustrated by Cardano. I close by suggesting that we should rely more heavily on resources of Anti-Individualism as a framework for understanding the acquisition and possession of concepts of abstract subject matters.     

Feature integration in natural language concepts

Two experiments measured the joint influence of three key sets of semantic features on the frequency with which artifacts (Experiment 1) or plants and creatures (Experiment 2) were categorized in familiar categories. For artifacts, current function outweighed both originally intended function and current appearance. For biological kinds, appearance and behavior, an inner biological function, and appearance and behavior of offspring all had similarly strong effects on categorization. The data were analyzed to determine whether an independent cue model or an interactive model best accounted for how the effects of the three feature sets combined. Feature integration was found to be additive for artifacts but interactive for biological kinds. In keeping with this, membership in contrasting artifact categories tended to be superadditive, indicating overlapping categories, whereas for biological kinds, it was subadditive, indicating conceptual gaps between categories. It is argued that the results underline a key domain difference between artifact and biological concepts.     

Conceptual combination: Conjunction and negation of natural concepts

The operation of negation on combinations of natural categories was examined in two experiments. In the first, category membership ratings of lists of items were obtained for pairs of concepts considered individually and in two logical combinations: conjunctions (e.g., “Tools which are also Weapons”) and negated conjunctions—forms of those conjunctions in which the modifier noun category was negated (“Tools which arenot Weapons”). For conjunctions, results supported earlier findings of overextension and the geometric averaging of constituent membership values (Hampton, 1988b). Previous findings of concept dominance and noncommutativity within conjunctions were also replicated, both for typicality ratings and for probability of class membership. For negated conjunctions, the pattern of dominance was similar but interacted with order within the conjunction. Negated conjunctions were also overextended. The second experiment explored how the attributes of negated conjunctions were derived from those of the two component concepts. Frequency of generation of attributes expressed positively (has wheels) or negatively (has no wheels) followed rated frequency in the negated category. The distinctiveness of an attribute to distinguish the complement from the head-noun class was associated with the generation of attributes, particularly when there was relatively high overlap between the two categories.     

Standard back-translation procedures may not capture proper emotion concepts: a case study of Chinese disgust terms

We present data questioning the adequacy of standard back-translation procedures for investigating emotion states across cultures (Brislin, 1970). Our data indicate that the Chinese back-translation of the term disgust has led cross-cultural researchers to accept terms whose themes, goals, and motivations are more akin to the English term anger. Evidence is presented showing that, compared with the standard back-translation method, a more painstaking interview method found a better translational Chinese equivalent for the English term disgust. Implications for the use of back-translation in cross-cultural research are considered.     

Linear separability in superordinate natural language concepts

Two experiments are reported in which linear separability was investigated in superordinate natural language concept pairs (e.g., toiletry-sewing gear). Representations of the exemplars of semantically related concept pairs were derived in two to five dimensions using multidimensional scaling (MDS) of similarities based on possession of the concept features. Next, category membership, obtained from an exemplar generation study (in Experiment 1) and from a forced-choice classification task (in Experiment 2) was predicted from the coordinates of the MDS representation using log linear analysis. The results showed that all natural kind concept pairs were perfectly linearly separable, whereas artifact concept pairs showed several violations. Clear linear separability of natural language concept pairs is in line with independent cue models. The violations in the artifact pairs, however, yield clear evidence against the independent cue models.     

Swazi children's understanding of time concepts: a Piagetian study

The development of conservation skills in tasks dealing with temporal and nontemporal concepts was investigated. Contrary to findings of previous researchers, time conservation tasks presented few difficulties for children from a non-technological culture. Consistent with the results of previous research, however, time conservation tasks did appear to be more difficult than related tasks employing similar materials.     

Exemplars and prototypes in natural language concepts: A typicality-based evaluation

Are natural language categories represented by instances of the category or by a summary representation? We used an exemplar model and a prototype model, both derived within the framework of the generalized context model (Nosofsky, 1984, 1986), to predict typicality ratings for 12 superordinate natural language concepts. The models were fitted to typicality ratings averaged across participants and to the typicality judgments of individual participants. Both analyses yielded results in favor of the exemplar model. These results suggest that higher-level natural language concepts are represented by their subordinate members, rather than by a summary representation.     

Personalistic concepts in action: The case of Adolf Hitler

Grounded in his personalistic worldview, William Stern regarded persons as inherently valuable beings who use values to conduct their lives. One might wonder if such a value-laden and idealistic approach can be applied to the case of Adolf Hitler, who clearly was a very destructive and disharmonious figure. In order to deal with this challenging question we will refer to three personalistic principles, namely convergence, introception, and unitas multiplex. As our analysis shows, all three principles can be exemplified in the case of Hitler if a neutralized version of each principle is used. By the demonstration of “iron will” he strived for coherence and unity, and was tremendously successful in managing that his followers introcepted the Nazi ideals. The convergence principle also applies to Hitler since there was unique conjunction of his traits with influences of his era.     

The automatic evaluation of novel stimuli

From classic theory and research in psychology, we distill a broad theoretical statement that evaluative responding can be immediate, unintentional, implicit, stimulus based, and linked directly to approach and avoidance motives. This statement suggests that evaluative responses should be elicited by novel, nonrepresentational stimuli (e.g., abstract art, "foreign" words). We tested this hypothesis through combining the best features of relevant automatic–affect research paradigms. We first obtained explicit evaluative ratings of novel stimuli. From these, we selected normatively positive and negative stimuli to use as primes in a sequential priming paradigm. Two experiments using this paradigm demonstrated that briefly presented novel prime stimuli were evaluated automatically, as they facilitated responses to subsequently presented target stimuli of the same valence just as much as did pictures or names of real objects. A final experiment revealed that exposure to novel stimuli produces muscular predispositions to approach or avoid them.     

The generative basis of natural number concepts

Number concepts must support arithmetic inference. Using this principle, it can be argued that the integer concept of exactly ONE is a necessary part of the psychological foundations of number, as is the notion of the exact equality - that is, perfect substitutability. The inability to support reasoning involving exact equality is a shortcoming in current theories about the development of numerical reasoning. A simple innate basis for the natural number concepts can be proposed that embodies the arithmetic principle, supports exact equality and also enables computational compatibility with real- or rational-valued mental magnitudes.