Category Boundaries Research Articles

The relationship between tics, OC, ADHD and autism symptoms: A cross- disorder symptom analysis in Gilles de la Tourette syndrome patients and family-members

Gilles de la Tourette's syndrome (GTS) is a disorder in which obsessive-compulsive (OC), Attention Deficit Hyperactivity Disorder (ADHD) and autism symptoms occur in up to 60% of patients, suggesting shared etiology. We explored the phenotypic structure of tic, OC, ADHD, and autism symptoms as measured by the YGTSS,Y-BOCS,CAARS and AQ, in 225 GTS patients and 371 family members. First, Confirmatory Factor Analyses (CFA) were performed on the symptom structure of each separate symptom scale. Second, the symptom dimensions derived from each scale were combined in one model, and correlations between them were calculated. Using the correlation matrix, Exploratory Factor Analyses (EFA) were performed on the symptom dimensions across the scales. EFA revealed a five factor structure: tic/aggression/symmetry; OC symptoms/compulsive tics/ numbers and patterns; ADHD symptoms; autism symptoms; and hoarding/inattention symptoms. The results are partly in line with the traditional categorical boundaries of the symptom scales used, and partly reveal a symptom structure that cuts through the diagnostic categories. This phenotypic structure might more closely reflect underlying etiologies than a structure that classically describes GTS patients according to absence or presence of comorbid OCD, ADHD and autism, and might inform both future genetic and treatment studies.

Blurring Human–Machine Distinctions: Anthropomorphic Appearance in Social Robots as a Threat to Human Distinctiveness

The present research aims at gaining a better insight on the psychological barriers to the introduction of social robots in society at large. Based on social psychological research on intergroup distinctiveness, we suggested that concerns toward this technology are related to how we define and defend our human identity. A threat to distinctiveness hypothesis was advanced. We predicted that too much perceived similarity between social robots and humans triggers concerns about the negative impact of this technology on humans, as a group, and their identity more generally because similarity blurs category boundaries, undermining human uniqueness. Focusing on the appearance of robots, in two studies we tested the validity of this hypothesis. In both studies, participants were presented with pictures of three types of robots that differed in their anthropomorphic appearance varying from no resemblance to humans (mechanical robots), to some body shape resemblance (biped humanoids) to a perfect copy of human body (androids). Androids raised the highest concerns for the potential damage to humans, followed by humanoids and then mechanical robots. In Study 1, we further demonstrated that robot anthropomorphic appearance (and not the attribution of mind and human nature) was responsible for the perceived damage that the robot could cause. In Study 2, we gained a clearer insight in the processes underlying this effect by showing that androids were also judged as most threatening to the human–robot distinction and that this perception was responsible for the higher perceived damage to humans. Implications of these findings for social robotics are discussed.

The Effect of Residual Acoustic Hearing and Adaptation to Uncertainty on Speech Perception in Cochlear Implant Users: Evidence From Eye-Tracking.

While outcomes with cochlear implants (CIs) are generally good, performance can be fragile. The authors examined two factors that are crucial for good CI performance. First, while there is a clear benefit for adding residual acoustic hearing to CI stimulation (typically in low frequencies), it is unclear whether this contributes directly to phonetic categorization. Thus, the authors examined perception of voicing (which uses low-frequency acoustic cues) and fricative place of articulation (s/∫, which does not) in CI users with and without residual acoustic hearing. Second, in speech categorization experiments, CI users typically show shallower identification functions. These are typically interpreted as deriving from noisy encoding of the signal. However, psycholinguistic work suggests shallow slopes may also be a useful way to adapt to uncertainty. The authors thus employed an eye-tracking paradigm to examine this in CI users. Participants were 30 CI users (with a variety of configurations) and 22 age-matched normal hearing (NH) controls. Participants heard tokens from six b/p and six s/∫ continua (eight steps) spanning real words (e.g., beach/peach, sip/ship). Participants selected the picture corresponding to the word they heard from a screen containing four items (a b-, p-, s- and ∫-initial item). Eye movements to each object were monitored as a measure of how strongly they were considering each interpretation in the moments leading up to their final percept. Mouse-click results (analogous to phoneme identification) for voicing showed a shallower slope for CI users than NH listeners, but no differences between CI users with and without residual acoustic hearing. For fricatives, CI users also showed a shallower slope, but unexpectedly, acoustic + electric listeners showed an even shallower slope. Eye movements showed a gradient response to fine-grained acoustic differences for all listeners. Even considering only trials in which a participant clicked "b" (for example), and accounting for variation in the category boundary, participants made more looks to the competitor ("p") as the voice onset time neared the boundary. CI users showed a similar pattern, but looked to the competitor more than NH listeners, and this was not different at different continuum steps. Residual acoustic hearing did not improve voicing categorization suggesting it may not help identify these phonetic cues. The fact that acoustic + electric users showed poorer performance on fricatives was unexpected as they usually show a benefit in standardized perception measures, and as sibilants contain little energy in the low-frequency (acoustic) range. The authors hypothesize that these listeners may overweight acoustic input, and have problems when this is not available (in fricatives). Thus, the benefit (or cost) of acoustic hearing for phonetic categorization may be complex. Eye movements suggest that in both CI and NH listeners, phoneme categorization is not a process of mapping continuous cues to discrete categories. Rather listeners preserve gradiency as a way to deal with uncertainty. CI listeners appear to adapt to their implant (in part) by amplifying competitor activation to preserve their flexibility in the face of potential misperceptions.

Technology convergence and the performance of boundary spanning products

This study examines the performance of products that span their category boundaries in technologically converging industries. While few studies systematically explore the demand side implications o...

Lexical processing depends on sublexical processing: Evidence from the visual world paradigm with aphasia

Lexical processing depends on sublexical processing: Evidence from the visual world paradigm with aphasia

Haptic and Tactile Adjectives Are Consistently Mapped onto Color Space.

Cross-modal associations refer to non-arbitrary associations of features across sensory modalities. Such associations have been observed between many different sensory features. One association that has rarely been studied so far is between touch and color. In this study, participants were asked to match tactile and haptic adjectives to color samples shown individually on a screen. They could select one to 11 tactile and haptic terms, presented in 11 pairs of opposed adjectives. The results showed a regular pattern in the way tactile and haptic terms were matched to color. Our results further revealed that the colors to which tactile and haptic terms were matched did not fall within the boundaries of color lexical categories, suggesting that the associations were not based on lexicon--despite the frequent occurrence of linguistic expressions such as 'soft pink', not all colors called 'pink' were matched to 'soft'. In contrast with one recent study, the distribution of tactile and haptic terms across the Munsell array suggests that along with brightness and chroma, hue was also relevant to participants' responses. Specifically in the case of hue, several opposed adjectives were relatively well matched to opposed colors, along the orthogonal Yellow/Blue and Red/Green axes, which are suggested to structure the space of hue experience. Possible accounts of these results are considered.

Application and research of fuzzy clustering analysis algorithm under “micro-lecture” English teaching mode

The fuzzy clustering algorithm is to classify the data or indicators with a greater degree of similarity based on the principle of the same type of individuals possessing a greater similarity, and different types of individuals possessing differences, establish clear category boundaries, form any shape of relationship clusters in the solving process, and input the research indicators at random, in order to accurately analyze the significance of the indicators in the algorithm. The evaluation value of the clustering analysis can be obtained by the establishment of the fuzzy factor set based on the membership analysis, and the evaluation result can be analyzed through reference to the evaluation indicators of the fuzzy clustering analysis. The “micro-lecture” English teaching mode can be estimated and the analysis indicators can be rationally established based on the fuzzy clustering analysis algorithm, with better algorithm applicability.

The influence of labels and facts on children’s and adults’ categorization

Language has been assumed to influence categorization for both adults and children but the precise role and potency of linguistic labels in category formation remains open. Here we explore how linguistic labels help fit objects into categories when relevant perceptual information is either ambiguous or inconsistent with the labels. We also ask how the effects of labels compare to those of other types of information such as facts. We presented 4-year-old children and adults with tasks in which they had to categorize a perceptually ambiguous natural-kind stimulus with one of two equidistant standards (Exp. 1 and 2) or group an ambiguous natural-kind stimulus into a category with a perceptually dissimilar standard (Exp. 3). Participants had access to labels (e.g., “This one is a lorp/pim”), observable facts (e.g., “This one has a long/short beak”), or unobservable facts (e.g., “This one drinks water/milk”) that grouped the ambiguous stimulus with one of the standards. Both children and adults followed label- and fact-driven category boundaries for perceptually ambiguous stimuli (Exp. 1 and 2), and continued to do so even when the labels or facts pointed to perceptually incongruent categories (Exp. 3). These findings suggest a strong causal role for both labels and facts in categorization and have implications about theories of how categorization develops in children.

A Bayesian Model of Grounded Color Semantics

Natural language meanings allow speakers to encode important real-world distinctions, but corpora of grounded language use also reveal that speakers categorize the world in different ways and describe situations with different terminology. To learn meanings from data, we therefore need to link underlying representations of meaning to models of speaker judgment and speaker choice. This paper describes a new approach to this problem: we model variability through uncertainty in categorization boundaries and distributions over preferred vocabulary. We apply the approach to a large data set of color descriptions, where statistical evaluation documents its accuracy. The results are available as a Lexicon of Uncertain Color Standards (LUX), which supports future efforts in grounded language understanding and generation by probabilistically mapping 829 English color descriptions to potentially context-sensitive regions in HSV color space.

The Categorical Imperative and Structural Reproduction: Dynamics of Technological Entry in the Semiconductor Industry

Extant organizational literature argues that straddling institutionalized categories begets an illegitimacy discount, leading organizations to reproduce established categorical boundaries. If gaining legitimacy requires compliance with this “categorical imperative,” why do we frequently observe categorical straddling even in uncontested and fully institutionalized categorical structures? To address this question, we propose that de novo (i.e., newly founded) and de alio (i.e., diversifying) organizations respond differently to the categorical imperative. Specifically, de novo organizations are more likely to enter and fit in high-contrast categories than in low-contrast ones, whereas the opposite is true for de alio entrants. To test these hypotheses, we follow technological entry dynamics within the semiconductor industry between 1976 and 2002. Using patent information, we examine how category contrast affects which technological categories de novo and de alio organizations enter, and the performance associated with those entry events. A comprehensive set of empirical analyses lend support to our hypotheses. Besides clarifying the link between the categorical imperative and structural reproduction, this study bears implications for entrepreneurship and strategy research on entry dynamics.

Discourse appropriation and category boundary work: casual teachers in the market

ABSTRACTWith the increasing casualisation of the teacher labour force, there is little written on the experiences of casual teachers and the challenges they face in brokering professional identities within constantly shifting and uncertain work contexts. Being a category bound casual teacher (a product of category boundary work) is a complex subject position. The aim of this article is to advance our understandings of the identity work inherent in casual relief teachers (CRTs) performativity. Anti-essentialist theories support this exploration of CRT subjectivities and processes of discourse appropriation. Using collective biography methodology as re-storied memory work, this article speaks back to neoliberal politics of casualisation. The stories draw attention to how both experienced practitioners and newly graduated teachers might ‘do’ category boundary work within the complexity of school politics as they navigate the uncertainty of gaining and maintaining employment in the Education market.

Categorical perception of color: evidence from secondary category boundary.

Despite a plethora of behavioral research exploring the phenomenon of color categorical perception (CP) known as “better discrimination between pair of colors stimuli from different categories and pair of colors stimuli from the same category even when the stimulus differences between the pairs of stimuli are equal”, most of the evidence for the CP of color was derived from Roman or top-to-down script readers and very rarely from right-to-left script readers in primary category. To date, no studies of color CP have been conducted on right-to-left script readers in secondary category boundary to support this theory. Three experiments have been conducted: Experiments 1 and 2 established the Arabic blue–purple secondary category boundary, and Experiment 3 tested the CP of color in the blue–purple category boundary. Sixty participants (30 men and 30 women) took part in this study. All spoke Arabic as their first language, and all were undergraduate or postgraduate students at King Saud University. Their ages ranged from 18–35 years with a mean age of 21.9 years (SD =5.2). The result indicated that for Experiments 1 and 2, it appeared that the Arabic blue–purple category boundary was approximately 10PB and it is in the same location as for English. For Experiment 3, reaction times in the between-categories condition were significantly faster than those in the within-category condition; this suggested that CP of color was shown in the Arabic’s blue–purple secondary category boundary.

Feature expectation heightens visual sensitivity during fine orientation discrimination.

Attending to a stimulus enhances the sensitivity of perceptual decisions. However, it remains unclear how perceptual sensitivity varies according to whether a feature is expected or unexpected. Here, observers made fine discrimination judgments about the orientation of visual gratings embedded in low spatial-frequency noise, and psychophysical reverse correlation was used to estimate decision 'kernels' that revealed how visual features influenced choices. Orthogonal cues alerted subjects to which of two spatial locations was likely to be probed (spatial attention cue) and which of two oriented gratings was likely to occur (feature expectation cue). When an expected (relative to unexpected) feature occurred, decision kernels shifted away from the category boundary, allowing observers to capitalize on more informative, "off-channel" stimulus features. By contrast, the spatial attention cue had a multiplicative influence on decision kernels, consistent with an increase in response gain. Feature expectation thus heightens sensitivity to the most informative visual features, independent of selective attention.

The Louvain-La-Neuve sea ice model LIM3.6: global and regional capabilities

Abstract. The new 3.6 version of the Louvain-la-Neuve sea ice model (LIM) is presented, as integrated in the most recent stable release of Nucleus for European Modelling of the Ocean (NEMO) (3.6). The release will be used for the next Climate Model Inter-comparison Project (CMIP6). Developments focussed around three axes: improvements of robustness, versatility and sophistication of the code, which involved numerous changes. Robustness was improved by enforcing exact conservation through the inspection of the different processes driving the air–ice–ocean exchanges of heat, mass and salt. Versatility was enhanced by implementing lateral boundary conditions for sea ice and more flexible ice thickness categories. The latter includes a more practical computation of category boundaries, parameterizations to use LIM3.6 with a single ice category and a flux redistributor for coupling with atmospheric models that cannot handle multiple sub-grid fluxes. Sophistication was upgraded by including the effect of ice and snow weight on the sea surface. We illustrate some of the new capabilities of the code in two standard simulations. One is an ORCA2-LIM3 global simulation at a nominal 2° resolution, forced by reference atmospheric climatologies. The other one is a regional simulation at 2 km resolution around the Svalbard Archipelago in the Arctic Ocean, with open boundaries and tides. We show that the LIM3.6 forms a solid and flexible base for future scientific studies and model developments.

Explaining the Timing of Natural Scene Understanding with a Computational Model of Perceptual Categorization.

Observers can rapidly perform a variety of visual tasks such as categorizing a scene as open, as outdoor, or as a beach. Although we know that different tasks are typically associated with systematic differences in behavioral responses, to date, little is known about the underlying mechanisms. Here, we implemented a single integrated paradigm that links perceptual processes with categorization processes. Using a large image database of natural scenes, we trained machine-learning classifiers to derive quantitative measures of task-specific perceptual discriminability based on the distance between individual images and different categorization boundaries. We showed that the resulting discriminability measure accurately predicts variations in behavioral responses across categorization tasks and stimulus sets. We further used the model to design an experiment, which challenged previous interpretations of the so-called “superordinate advantage.” Overall, our study suggests that observed differences in behavioral responses across rapid categorization tasks reflect natural variations in perceptual discriminability.

Category Boundaries and Typicality Warp the Neural Representation Space of Real-World Object Categories

Category Boundaries and Typicality Warp the Neural Representation Space of Real-World Object Categories

Human substantia nigra neurons encode decision outcome and are modulated by categorization uncertainty in an auditory categorization task.

The ability to categorize stimuli – predator or prey, friend or foe – is an essential feature of the decision-making process. Underlying that ability is the development of an internally generated category boundary to generate decision outcomes. While classic temporal difference reinforcement models assume midbrain dopaminergic neurons underlie the prediction error required to learn boundary location, these neurons also demonstrate a robust response to nonreward incentive stimuli. More recent models suggest that this may reflect a motivational aspect to performing a task which should be accounted for when modeling dopaminergic neuronal behavior. To clarify the role of substantia nigra dopamine neurons in uncertain perceptual decision making, we investigated their behavior using single neuron extracellular recordings in patients with Parkinson's disease undergoing deep brain stimulation. Subjects underwent a simple auditory categorical decision-making task in which they had to classify a tone as either low- or high-pitched relative to an explicit threshold tone and received feedback but no reward. We demonstrate that the activity of human SN dopaminergic neurons is predictive of perceptual categorical decision outcome and is modulated by uncertainty. Neuronal activity was highest during difficult (uncertain) decisions that resulted in correct responses and lowest during easy decisions that resulted in incorrect responses. This pattern of results is more consistent with a “motivational” role with regards to perceptual categorization and suggests that dopamine neurons are most active when critical information – as represented by uncertainty – is available for learning decision boundaries.

Context-dependent categorical perception in a songbird

The division of continuously variable acoustic signals into discrete perceptual categories is a fundamental feature of human speech. Other animals have been found to categorize speech sounds much the same as humans do, although little is known of the role of categorical perception by animals in their own natural communication systems. A hallmark of human categorical perception of speech is that linguistic context affects both how speech sounds are categorized into phonemes, and how different versions of phonemes are produced. I first review earlier findings showing that a species of songbird, the swamp sparrow, categorically perceives the notes that constitute its learned songs and that individual neurons in the bird’s brain show categorical responses that map onto its behavioral response. I then present more recent data, using both discrimination and labeling tests, that show how swamp sparrows perceive categorical boundaries differently depending on context. These results demonstrate that there is a more complex relationship between underlying categorical representations and surface forms in the perception of birdsong. To our knowledge, this work suggests for the first time that this higher-order characteristic of human phonology is also found in a nonhuman communication system.

1H NMR studies of water- and alkaline-soluble organic matter from fine urban atmospheric aerosols

Solution-state 1H NMR spectroscopy was applied to characterize the structural features of water- and alkaline-soluble organic matter (WSOM and ASOM, respectively) sequentially extracted from fine urban atmospheric aerosols collected over different seasons. The objectives of this study were twofold: (i) to compare the functional characteristics of fine aerosol WSOM and the yet unknown ASOM, and (ii) to assess the sources of WSOM and ASOM at an urban location. The 1H NMR analysis confirmed that the WSOM and ASOM fractions hold similar 1H functional groups; however, they differ in terms of their relative distribution throughout the seasons. The winter and autumn samples have a less aliphatic and oxidized character and higher contributions from aromatic groups than those of warmer conditions. The urban aerosol WSOM and ASOM fractions do not fit the established 1H NMR source apportionment fingerprints of marine, secondary, and biomass burning organic aerosols (OAs), exhibiting a smaller relative contribution of carbon-oxygen double bonds, which is indicative of a less oxidized character. These results confirm that the boundaries of the pre-established source categories, especially for secondary and biomass burning OAs, might be different at urban locations, suggesting the need to improve the 1H NMR source apportionment model for including a new fingerprint for urban OAs.

Differences in perceptual learning transfer as a function of training task.

A growing body of research--including results from behavioral psychology, human structural and functional imaging, single-cell recordings in nonhuman primates, and computational modeling--suggests that perceptual learning effects are best understood as a change in the ability of higher-level integration or association areas to read out sensory information in the service of particular decisions. Work in this vein has argued that, depending on the training experience, the "rules" for this read-out can either be applicable to new contexts (thus engendering learning generalization) or can apply only to the exact training context (thus resulting in learning specificity). Here we contrast learning tasks designed to promote either stimulus-specific or stimulus-general rules. Specifically, we compare learning transfer across visual orientation following training on three different tasks: an orientation categorization task (which permits an orientation-specific learning solution), an orientation estimation task (which requires an orientation-general learning solution), and an orientation categorization task in which the relevant category boundary shifts on every trial (which lies somewhere between the two tasks above). While the simple orientation-categorization training task resulted in orientation-specific learning, the estimation and moving categorization tasks resulted in significant orientation learning generalization. The general framework tested here--that task specificity or generality can be predicted via an examination of the optimal learning solution--may be useful in building future training paradigms with certain desired outcomes.