Internal Structure Of Categories Research Articles

Influence of the European Portuguese phonological system on the perception of close-mid and open-mid vowels

This study’s purpose was to analyse the influence of neutralisation on the perception of European Portuguese (EP) close-mid and open-mid vowels, and the gradient between the /i/, /e/, /ε/ and /a/ phonological categories. A fuzzy boundary between mid-vowels has been described in the phonological systems of various languages including EP, a variety of Portuguese with complex phonological phenomena and exceptional realisations of vowels in different contexts. Fifteen listeners from Lisbon participated in two tasks: Identification and goodness rating of 20 random repetitions of 31 stimuli from a /i/-/e/-/ε/-/a/ continuum. The boundaries between categories in the identification task, the internal structures of each category and the gradient of each boundary in the goodness rating task were analysed. Logistic regression was used to analyse the individual responses of listeners and the internal structure of phonemic categories, and prototypes were determined using bubble charts of goodness scores. The gradient of boundaries was analysed using two sets of data: X responses and goodness ratings. Models of the gradients of transition were developed using a mixed effects regression approach. Results from the identification task showed four vowel categories marked by three distinct boundaries. The stimulus with the highest score was approximately in the centroid and the goodness score decreased as the stimulus moved away from the centroid, which constitutes new evidence of an internal structure of the phonemic categories in EP. The main implications of the results obtained are for the description and typology of phonological phenomena in EP, supporting the existence of a non-partial contrast (which does not neutralise in any context) between /ε/ and /a/, and revealing less robust /i/-/e/ and /e/-/ε/ phonemic oppositions.

Relationships between native and non-native speech perception.

Individuals differ in their ability to perceive and learn unfamiliar speech sounds, but we lack a comprehensive theoretical account that predicts individual differences in this skill. Predominant theories largely attribute difficulties of non-native speech perception to the relationships between non-native speech sounds/contrasts and native-language categories. The goal of the current study was to test whether the predictions made by these theories can be extended to predict individual differences in naive perception of non-native speech sounds or learning of these sounds. Specifically, we hypothesized that the internal structure of native-language speech categories is the cause of difficulty in perception of unfamiliar sounds such that learners who show more graded (i.e., less categorical) perception of sounds in their native language would have an advantage for perceiving non-native speech sounds because they would be less likely to assimilate unfamiliar speech tokens to their native-language categories. We tested this prediction in two experiments in which listeners categorized speech continua in their native language and performed tasks of discrimination or identification of difficult non-native speech sound contrasts. Overall, results did not support the hypothesis that individual differences in categorical perception of native-language speech sounds is responsible for variability in sensitivity to non-native speech sounds. However, participants who responded more consistently on a speech categorization task showed more accurate perception of non-native speech sounds. This suggests that individual differences in non-native speech perception are more related to the stability of phonetic processing abilities than to individual differences in phonetic category structure. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Perceptual effects of lexical competition on Cantonese tone categories

Listeners use lexical information and the speech signal to categorize sounds and recognize words despite substantial acoustic-phonetic variation in natural speech. In diachronic mergers, where systematic variation acts to neutralize lexical contrasts, the role of the lexicon becomes less clear. We examined how lexical competition structures phonetic variability of (merging) lexical tone categories in Cantonese using three experiments. Listeners categorized tokens from lexical tone continua generated from minimal pairs (Experiment 1: Word identification) and categorized tokens from tone continua generated from word-nonword pairs (Experiment 2: Lexical decision). The presence of a lexical competitor at both continuum endpoints in Experiment 1 maintained more discrete categorization functions for non-merging tone pairs than in Experiment 2 where only one endpoint was a word. In the merging tone pairs, categorization was less discrete and the effect of lexical competition was different. Exploratory data from a goodness rating task, Experiment 3, suggest that lexical competition affects internal category structure for merging tones, but not non-merging tones. Overall, these data provide evidence that tone mergers affect phonetic category boundaries and internal category structure in the lexicon, and that, for non-merging tones, the range of acceptable phonetic variation is constrained by the presence of a lexical competitor.

Internal structure of intonational categories: The (dis)appearance of a perceptual magnet effect.

The question of whether intonation events are speech categories like phonemes and lexical tones has long been a puzzle in prosodic research. In past work, researchers have studied categoricality of pitch accents and boundary tones by examining perceptual phenomena stemming from research on phoneme categories (i.e., intonation boundary effects-peaks in discrimination sensitivity at category boundaries, perceptual magnet effects-sensitivity minima near the best exemplar or prototype of a category). Both lines of research have yielded mixed results. However, boundary effects are not necessarily related to categoricality of speech. Using improved methodology, the present study examines whether pitch accents have domain-general internal structure of categories by testing the perceptual magnet effect. Perceived goodness and discriminability of re-synthesized productions of Dutch rising pitch accent (L*H) were evaluated by native speakers of Dutch in three experiments. The variation between these stimuli was quantified using a polynomial-parametric modeling approach. A perceptual magnet effect was detected: (1) rated "goodness" decreased as acoustic-perceptual distance relative to the prototype increased (Experiment 1), and (2) equally spaced items far from the prototype were more frequently discriminated than equally spaced items in the neighborhood of the prototype (Experiment 2). These results provide first evidence for internal structure of pitch accents, similar to that found in color and phoneme categories. However, the discrimination accuracy gathered here was lower than that reported for phonemes. The discrimination advantage in the neighborhood far from the prototype disappeared when participants were tested on a very large number of stimuli (Experiment 3), similar to findings on phonemes and different from findings for lexical tones in neutral network simulations of distributional learning. These results suggest a more transient nature of the perceptual magnet effect in the perception of pitch accents and arguably weaker categoricality of pitch accents, compared to that of phonemes and in particular of lexical tones.

Introducing the structural bases of typicality effects in deep learning

In this paper, we hypothesize that the effects of the degree of typicality in natural semantic categories can be generated based on the structure of artificial categories learned with deep learning models. Motivated by the human approach to representing natural semantic categories and based on the Prototype Theory foundations, we propose a novel Computational Prototype Model (CPM) to represent the internal structure of semantic categories. Unlike other prototype learning approaches, our mathematical framework proposes a first approach to provide deep neural networks with the ability to model abstract semantic concepts such as category central semantic meaning, typicality degree of an object's image, and family resemblance relationship. We proposed several methodologies based on the typicality's concept to evaluate our CPM-model in image semantic processing tasks such as image classification, a global semantic description, and transfer learning. Our experiments on different image datasets, such as ImageNet and Coco, showed that our approach might be an admissible proposition in the effort to endow machines with greater power of abstraction for the semantic representation of objects' categories.

Category Structure and Categorical Perception Jointly Explained by Similarity-Based Information Theory.

Categorization is a fundamental information processing phenomenon in the brain. It is critical for animals to compress an abundance of stimulations into groups to react quickly and efficiently. In addition to labels, categories possess an internal structure: the goodness measures how well any element belongs to a category. Interestingly, this categorization leads to an altered perception referred to as categorical perception: for a given physical distance, items within a category are perceived closer than items in two different categories. A subtler effect is the perceptual magnet: discriminability is reduced close to the prototypes of a category and increased near its boundaries. Here, starting from predefined abstract categories, we naturally derive the internal structure of categories and the phenomenon of categorical perception, using an information theoretical framework that involves both probabilities and pairwise similarities between items. Essentially, we suggest that pairwise similarities between items are to be tuned to render some predefined categories as well as possible. However, constraints on these pairwise similarities only produce an approximate matching, which explains concurrently the notion of goodness and the warping of perception. Overall, we demonstrate that similarity-based information theory may offer a global and unified principled understanding of categorization and categorical perception simultaneously.

Theoretical and applied issues of «price» of criminality and its calculation

The article is devoted to the study of the legal nature and the internal structure of such categories as «price» of criminality. Were determined conceptual approaches of establishing a «price» of criminality and also analyzed the prospects of their development. We highlighted issues related to the definition of specific integrative elements of such category as «price» of criminality.Determined the concept of «price» of crime, under which we propose to understand the direct or indirect costs of physical, material, spiritual and moral nature, which undergoes mankind as a result of the commission of criminal encroachments, expenses incurred by society in connection with the need to overcome the consequences of criminal acts, the keeping of the whole law enforcement, penitentiary system and other state institutions, as well as the aggregate assets of the criminal organizations and their costs to support their illegal activities. It is established that the crime price includes the following integrative components: a) Current price damage caused by criminal abuse; b) »price» of preventive measures to prevent crime; c) »price» as a «budget» of criminal activity.Analyzed the general theoretical approach according to which the «price» of crime is a direct and indirect harm, which is caused by society in connection with the commission of socially dangerous acts, is analyzed. An economic and socio-anthropological approach to determining the price of crime is considered. The main differential criterion of the aforementioned conceptual approaches is the attitude of their representatives to the possibility of establishing harm from criminal encroachments in absolute terms. It should be noted that the emphasis in this study is precisely in the socio-anthropological approach, since it is characterized by a greater degree of system validity.

More than a boundary shift: Perceptual adaptation to foreign-accented speech reshapes the internal structure of phonetic categories.

The literature on perceptual learning for speech shows that listeners use lexical information to disambiguate phonetically ambiguous speech sounds and that they maintain this new mapping for later recognition of ambiguous sounds for a given talker. Evidence for this kind of perceptual reorganization has focused on phonetic category boundary shifts. Here, we asked whether listeners adjust both category boundaries and internal category structure in rapid adaptation to foreign accents. We investigated the perceptual learning of Mandarin-accented productions of word-final voiced stops in English. After exposure to a Mandarin speaker's productions, native-English listeners' adaptation to the talker was tested in 3 ways: a cross-modal priming task to assess spoken word recognition (Experiment 1), a category identification task to assess shifts in the phonetic boundary (Experiment 2), and a goodness rating task to assess internal category structure (Experiment 3). Following exposure, both category boundary and internal category structure were adjusted; moreover, these prelexical changes facilitated subsequent word recognition. Together, the results demonstrate that listeners' sensitivity to acoustic-phonetic detail in the accented input promoted a dynamic, comprehensive reorganization of their perceptual response as a consequence of exposure to the accented input. We suggest that an examination of internal category structure is important for a complete account of the mechanisms of perceptual learning. (PsycINFO Database Record

Lexically guided perceptual tuning of internal phonetic category structure.

Listeners use lexical information to retune the mapping between the acoustic signal and speech sound representations, resulting in changes to phonetic category boundaries. Other research shows that phonetic categories have a rich internal structure; within-category variation is represented in a graded fashion. The current work examined whether lexically informed perceptual learning promotes a comprehensive reorganization of internal category structure. The results showed a reorganization of internal structure for one but not both of the examined categories, which may reflect an attenuation of learning for distributions with extensive category overlap. This finding points towards potential input-driven constraints on lexically guided phonetic retuning.

Construction of a Monadic Heyting Algebra in a Logos

Connections between certain types of categories (logoses and toposes) and intuitionistic predicate logic was established in 1960–1970 by Lowvere. The possibility of extending this connection to some types of modal logics by using the internal structure of categories of particular type (logos) was also established. Category-theoretical constructs were hence used as one of the possible semantic interpretations of intuitionistic logic. This interpretation has also included intuionistic modal logics using different semantical tools such as adjoint pair of functors. In this paper, we discuss one of the possible extension of intuitionistic logic.

Categorization: The View from Animal Cognition.

Exemplar, prototype, and rule theory have organized much of the enormous literature on categorization. From this theoretical foundation have arisen the two primary debates in the literature—the prototype-exemplar debate and the single system-multiple systems debate. We review these theories and debates. Then, we examine the contribution that animal-cognition studies have made to them. Animals have been crucial behavioral ambassadors to the literature on categorization. They reveal the roots of human categorization, the basic assumptions of vertebrates entering category tasks, the surprising weakness of exemplar memory as a category-learning strategy. They show that a unitary exemplar theory of categorization is insufficient to explain human and animal categorization. They show that a multiple-systems theoretical account—encompassing exemplars, prototypes, and rules—will be required for a complete explanation. They show the value of a fitness perspective in understanding categorization, and the value of giving categorization an evolutionary depth and phylogenetic breadth. They raise important questions about the internal similarity structure of natural kinds and categories. They demonstrate strong continuities with humans in categorization, but discontinuities, too. Categorization’s great debates are resolving themselves, and to these resolutions animals have made crucial contributions.

Category Membership and Semantic Coding in the Cerebral Hemispheres

Although a gradient of category membership seems to form the internal structure of semantic categories, it is unclear whether the 2 hemispheres of the brain differ in terms of this gradient. The 2 experiments reported here examined this empirical question and explored alternative theoretical interpretations. Participants viewed category names centrally and determined whether a closely related or distantly related word presented to either the left visual field/right hemisphere (LVF/RH) or the right visual field/left hemisphere (RVF/LH) was a member of the category. Distantly related words were categorized more slowly in the LVF/RH relative to the RVF/LH, with no difference for words close to the prototype. The finding resolved past mixed results showing an unambiguous typicality effect for both visual field presentations. Furthermore, we examined items near the fuzzy border that were sometimes rejected as nonmembers of the category and found both hemispheres use the same category boundary. In Experiment 2, we presented 2 target words to be categorized, with the expectation of augmenting the speed advantage for the RVF/LH if the 2 hemispheres differ structurally. Instead the results showed a weakening of the hemispheric difference, arguing against a structural in favor of a processing explanation.

Talker-specific influences on phonetic category structure.

A primary goal for models of speech perception is to describe how listeners achieve reliable comprehension given a lack of invariance between the acoustic signal and individual speech sounds. For example, individual talkers differ in how they implement phonetic properties of speech. Research suggests that listeners attain perceptual constancy by processing acoustic variation categorically while maintaining graded internal category structure. Moreover, listeners will use lexical information to modify category boundaries to learn to interpret a talker's ambiguous productions. The current work examines perceptual learning for talker differences that signal well-defined, unambiguous category members. Speech synthesis techniques were used to differentially manipulate talkers' characteristic productions of the stop voicing contrast for two groups of listeners. Following exposure to the talkers, internal category structure and category boundary were examined. The results showed that listeners dynamically adjusted internal category structure to be centered on experience with the talker's voice, but the category boundary remained fixed. These patterns were observed for words presented during training as well as novel lexical items. These findings point to input-driven constraints on functional plasticity within the language architecture, which may help to explain how listeners maintain stability of linguistic knowledge while simultaneously demonstrating flexibility for phonetic representations.

ABSTRACTIONIST CATEGORIES OF CATEGORIES

AbstractIf ${\cal C}$ is a category whose objects are themselves categories, and ${\cal C}$ has a rich enough structure, it is known that we can recover the internal structure of the categories in ${\cal C}$ entirely in terms of the arrows in ${\cal C}$. In this sense, the internal structure of the categories in a rich enough category of categories is visible in the structure of the category of categories itself.In this paper, we demonstrate that this result follows as a matter of logic – given one starts from the right definitions. This is demonstrated by first producing an abstraction principle whose abstracts are functors, and then actually recovering the internal structure of the individual categories that intuitively stand at the sources and targets of these functors by examining the way these functors interact. The technique used in this construction will be useful elsewhere, and involves providing an abstract corresponding not to every object of some given family, but to all the relevant mappings of some family of objects.This construction should settle, in particular, questions about whether categories of categories qualify as autonomous mathematical objects – categories of categories are perfectly acceptable autonomous objects and thus, in particular, suitable for foundational purposes.

Learning about the Internal Structure of Categories through Classification and Feature Inference

Previous research on category learning has found that classification tasks produce representations that are skewed toward diagnostic feature dimensions, whereas feature inference tasks lead to richer representations of within-category structure. Yet, prior studies often measure category knowledge through tasks that involve identifying only the typical features of a category. This neglects an important aspect of a category's internal structure: how typical and atypical features are distributed within a category. The present experiments tested the hypothesis that inference learning results in richer knowledge of internal category structure than classification learning. We introduced several new measures to probe learners' representations of within-category structure. Experiment 1 found that participants in the inference condition learned and used a wider range of feature dimensions than classification learners. Classification learners, however, were more sensitive to the presence of atypical features within categories. Experiment 2 provided converging evidence that classification learners were more likely to incorporate atypical features into their representations. Inference learners were less likely to encode atypical category features, even in a "partial inference" condition that focused learners' attention on the feature dimensions relevant to classification. Overall, these results are contrary to the hypothesis that inference learning produces superior knowledge of within-category structure. Although inference learning promoted representations that included a broad range of category-typical features, classification learning promoted greater sensitivity to the distribution of typical and atypical features within categories.

Talker-specific influences on phonetic category structure

A major goal of research in spoken language processing has been to describe how listeners achieve stable perception given the marked variability in mapping between the acoustic signal and linguistic representation. Toward this end, the research of Joanne L. Miller and colleagues has shown that speech sound categories, like other cognitive/perceptual categories, have rich internal structure, with category membership represented in a graded fashion. Moreover, category structure robustly shifts as a function of variation in the speech signal including variation associated with phonetic context, speaking rate, and dialect. I will discuss evidence indicating that internal structure also reflects talker-specific phonetic variation. These experiments concern talker differences in voice-onset-time (VOT), an acoustic parameter that marks the voicing distinction in stop consonants. I will begin with findings from production experiments that explicate talker differences in VOT with the goal of generating predictions for how listeners might accommodate such differences. I will then present findings from perception experiments indicating that listeners comprehensively adjust the mapping between the acoustic signal and phonetic category to reflect a talker's characteristic VOT distribution. Collectively, these findings demonstrate that listeners accommodate variability in the speech stream by dynamically adjusting internal category structure in light of systematic acoustic variation.

Developmental and gender-related trends of intra-talker variability in consonant production

This study investigates the effect of age and gender on the internal structure, cross-category distance, and discriminability of phonemic categories for two contrasts varying in fricative place of articulation (/s/-/∫/) and stop voicing (/b/-/p/) in word-initial tokens spoken by adults and normally developing children aged 9-14 yr. Vast between- and within-talker variability was observed with 16% of speakers exhibiting some degree of overlap between phonemic categories-a possible contribution to the range of talker intelligibility found in the literature. Females of all ages produced farther and thus more discriminable categories than males, although gender-marking for fricative between-category distance did not emerge until approximately 11 yr of age. Children produced farther yet also much more dispersed categories than adults with increasing discriminability with age, such that by age 13, children's categories were no less discriminable than those of adults. However, children's ages did not predict category distance or dispersion, indicating that convergence on adult-like category structure must occur later in adolescence.

Listeners’ sensitivity to talker differences in voice-onset-time: Phonetic boundaries and internal category structure

Recent findings indicate that listeners are sensitive to talker differences in phonetic properties of speech, including voice-onset-time (VOT) in word-initial stop consonants. The current work extends our earlier research by examining the degree to which listeners adjust the initial mapping from acoustic signal to segmental representation on a talker-specific basis. Two groups of listeners are exposed to a talker producing “cane.” Word-initial VOTs are manipulated such that one group hears “cane” produced with short VOTs and the other group hears “cane” produced with relatively longer VOTs. Following training, listeners’ voicing boundary for a /g/-/k/ continuum is tested. In addition, listeners are tested on phonetic category space by rating members of the continuum for typicality as /k/. If listeners adjust segmental mapping to accommodate talker differences in phonetic properties of speech, then we expect to observe a displacement in the voicing boundaries in line with earlier exposure. Moreover, if this adjustment entails a comprehensive reorganization of phonetic category space, then the /k/ exemplars rated most prototypical will also be displaced for the two listener groups. These data will be discussed in terms of potential constraints on talker-specificity in spoken language processing.

Quantifying the Internal Structure of Categories Using a Neural Typicality Measure

How categories are represented continues to be hotly debated across neuroscience and psychology. One topic that is central to cognitive research on category representation but underexplored in neurobiological research concerns the internal structure of categories. Internal structure refers to how the natural variability between-category members is coded so that we are able to determine which members are more typical or better examples of their category. Psychological categorization models offer tools for predicting internal structure and suggest that perceptions of typicality arise from similarities between the representations of category members in a psychological space. Inspired by these models, we develop a neural typicality measure that allows us to measure which category members elicit patterns of activation that are similar to other members of their category and are thus more central in a neural space. Using an artificial categorization task, we test how psychological and physical typicality contribute to neural typicality, and find that neural typicality in occipital and temporal regions is significantly correlated with subjects' perceptions of typicality. The results reveal a convergence between psychological and neural category representations and suggest that our neural typicality measure is a useful tool for connecting psychological and neural measures of internal category structure.

“Penguins don't fly”: An investigation into the effect of typicality on picture naming in people with aphasia

Background: Previous research has highlighted psycholinguistic variables influencing naming ability for individuals with aphasia, including: familiarity, frequency, age of acquisition, imageability, operativity, and length (Nickels & Howard, 1995) and a potential link between typicality and generalisation to untreated items in intervention (Kiran, Sandberg, & Sebastian, 2011). However, the effect of concept typicality (the extent to which an item can be considered a prototype of a category) on naming in aphasia warrants further examination. Aims: To investigate first whether typicality can be reliably rated across a range of natural semantic categories and second whether, and if so in which direction, typicality influences naming performance for people with aphasia. To provide quantitative and qualitative information on typicality for a set of stimuli for use in future research. Methods & Procedures: Typicality ratings were obtained and the results compared with those in the existing literature. The influence of typicality on picture naming was investigated employing both matched sets (high and low typicality matched for other psycholinguistic variables) and logistic regression analyses for the group and individual participants with aphasia (n = 20). Outcomes & Results: Typicality rating correlated strongly with ratings obtained in previous research (Rosch, 1975: r = .798, N = 35, p < .001; Uyeda & Mandler, 1980: r = .844, N = 47, p < .001). Typicality was a significant predictor of picture naming for the group and some individuals, with generally better performance for typical items. This was demonstrated in both matched sets and regression analyses. However, other psycholinguistic variables proved more strongly related to naming success, particularly age of acquisition. Conclusions: Typicality can be rated reliably and should be considered alongside other psycholinguistic variables when investigating word retrieval and intervention in aphasia. Further research is necessary to accurately model the direction of typicality effects found in word retrieval. Finally, the differing nature, size, and internal structure of categories require further exploration when investigating typicality effects.