Categorization Difficulty Research Articles

The categorization difficulty contributes to the uncanny valley without animacy

The categorization difficulty contributes to the uncanny valley without animacy

Challenges in the Assessment of Medullary Bone Invasion in Oral Cavity Cancers and Its Prognostic Significance.

As per AJCC 8th edition TNM staging system, bone invasion is a poor prognostic marker that upstages oral cavity squamous carcinoma (OSCC) to pT4a. Cortical erosion alone of bone or tooth socket by a gingival primary is not sufficient to upstage a tumour. The differentiation of cortical erosion from invasion through the cortical bone into the medulla is often challenging, limiting accurate staging. This review aims to assess the difficulties in differentiating cortical erosion from medullary invasion and evaluate the prognostic significance of different patterns of bone involvement. A retrospective review of OSCC with primary curative surgery and bone resection treated at a single-center over 10years, was performed to assess the prognostic significance of bone invasion. Hematoxylin-eosin stained slides of a subset of cases were re-reviewed in a planned manner to assess difficulties in precise categorization (no invasion/erosion/cortical invasion and medullary invasion), evaluate interobserver agreement, and correlate with clinical outcome. Five hundred and ninety patients were included, with a median follow-up of 28months. On univariate analysis, the 3-year local, nodal and distant metastasis control were not significantly different in the 3 groups of no invasion, erosion, and invasion (p = 0.43, 0.47, and 0.47, respectively). Overall survival (OS) at 3years was 78.1% and disease-free-survival(DFS) was 63.7% in the entire cohort. On univariate analysis, there was significant difference in OS and DFS based on these groups. This did not translate into independent prognostic benefit on multivariable analysis (p = 0.75 and 0.19, respectively). The independent prognostic factors were margin positivity, tumor differentiation, perineural invasion and pathological nodal involvement. Planned re-review of a subset of 202 cases resulted in a change in bone involvement category in 26/202 cases, which was mainly due to difficulty in assessing cortico-medullary junction near the tooth socket and bone fragmentation. The assessment showed moderate to near complete agreement (kappa 0.59-0.82) between 2 observers. Our study shows that bone involvement is not an independent prognostic marker and there is no specific correlation of medullary invasion with outcome over those that showed cortical erosion. Several factors contribute to difficulties and interobserver variability in assessing bone involvement.

Linear separability, irrelevant variability, and categorization difficulty.

In rule-based (RB) category-learning tasks, the optimal strategy is a simple explicit rule, whereas in information-integration (II) tasks, the optimal strategy is impossible to describe verbally. This study investigates the effects of two different category properties on learning difficulty in category learning tasks-namely, linear separability and variability on stimulus dimensions that are irrelevant to the categorization decision. Previous research had reported that linearly separable II categories are easier to learn than nonlinearly separable categories, but Experiment 1, which compared performance on linearly and nonlinearly separable categories that were equated as closely as possible on all other factors that might affect difficulty, found that linear separability had no effect on learning. Experiments 1 and 2 together also established a novel dissociation between RB and II category learning: increasing variability on irrelevant stimulus dimensions impaired II learning but not RB learning. These results are all predicted by the best available measures of difficulty in RB and II tasks. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Kategoryzacja w dyskursie zaburzonym – nazwy własne a nazwy pospolite

Aim of the study: the aim of the study was to assess the possibility of making a semantic categorization of common names and proper names by a person diagnosed with appointment aphasia. Method: the study used a case-experimental approach. The results were analyzed qualitatively and quantitatively. Results: the best-preserved semantic relations were indicated, the phenomena proving the quality of access to the mental dictionary were determined, the symptoms of degradation of the semantic dictionary were specified, the stage of processing disturbed was determined. The quantitative evaluation included the percentage description of the obtained results. Conclusions: A generally enhanced ability of the respondent to identify categorical proper names than common names was observed. This can probably be associated with the aforementioned specificity of proper names, related to their information entropy. We can talk about several causes of the observed dysfunctions, the most important seems to be the language deficit, manifested by impaired access to the semantic dictionary, dysfunctions in the field of metalinguistic operations within semantic networks, difficulties with updating words and, to some extent, the depletion of the resources of the mental lexicon. The test results should certainly also be considered in the context of cognitive dysfunctions. The results of this research are in accordance with previous findings suggesting that the difficulty of semantic categorization is related to the dysfunction of semantic memory in the field of categorization of the so-called fuzzy concepts.

The neural basis of ideological differences in race categorization

Multiracial individuals are often categorized as members of their 'socially subordinate' racial group-a form of social discrimination termed hypodescent-with political conservatives more likely than liberals to show this bias. Although hypodescent has been linked to racial hierarchy preservation motives, it remains unclear how political ideology influences categorization: Do conservatives and liberals see, feel or think about mixed-race faces differently? Do they differ in sensitivity to Black prototypicality (i.e. skin tone darkness and Afrocentric features) or racial ambiguity (i.e. categorization difficulty) of Black/White mixed-race faces? To help answer these questions, we collected a politically diverse sample of White participants and had them categorize mixed-race faces as Black or White during functional neuroimaging. We found that conservatism was related to greater anterior insula activity to racially ambiguous faces, and this pattern of brain activation mediated conservatives' use of hypodescent. This demonstrates that conservatives' greater sensitivity to racial ambiguity (rather than Black prototypicality) gives rise to greater categorization of mixed-race individuals into the socially subordinate group and tentatively suggests that conservatives may differ from liberals in their affective reactions to mixed-race faces. Implications for the study of race categorization and political psychology are discussed. This article is part of the theme issue 'The political brain: neurocognitive and computational mechanisms'.

Renal-cell carcinoma – novel concepts of classification

Abstract Renal cancer, according to the Polish National Cancer Registry, was the cause of 4% of cancer cases in men and 3% of cases in women in 2010. Most often it affects men over 65, although it may also concern infants. In 2010, the number of reported cases for men was 2,700 and 1,900 for women. For the last three decades – up to 1990, the incidence of kidney cancer has increased significantly. Currently, it remains at the stable level of morbidity. One of the most significant issues of modern diagnostics and treatment of renal cancer is the problem of its heterogeneity brin-ging many difficulties in systematization and categorization of this neoplasm. The World Health Organization Classification of Renal Tumors has been published in 2004 and is currently supplemented with new classification units, which, according to ISUP (International Society of Urological Pathology), should be considered as separate groups of kidney epithelial cancers.

The easy-to-hard training advantage with real-world medical images

Many medical professions require practitioners to perform visual categorizations in domains such as radiology, dermatology, and neurology. However, acquiring visual expertise is tedious and time-consuming and the perceptual strategies mediating visual categorization skills are poorly understood. In this paper, the Ease algorithm was developed to predict an item’s categorization difficulty (Ease value) based on the item’s perceptual similarity to all within-category items versus between-category items in the dataset. In this study, Ease values were used to construct an easy-to-hard and hard-to-easy training schedule for teaching melanoma diagnosis. Whereas previous visual training studies suggest that an easy-to-hard schedule benefits learning outcomes, no studies to date have demonstrated the easy-to-hard advantage with complex, real-world images. In our study, 237 melanoma and benign images were collected for training and testing purposes. The diagnostic accuracy of images was verified by an expert dermatologist. Based on their Ease values, the items were grouped into easy, medium, and hard categories, each containing an equal number of melanoma and benign lesions. During training, participants categorized images of skin lesions as either benign or melanoma and were given corrective feedback after each trial. In the easy-to-hard training condition, participants learned to categorize all the easy items first, followed by the medium items, and finally the hard items. Participants in the hard-to-easy training condition learned items in the reverse order. Post-training results showed that training in both conditions transferred to the classification of new melanoma and benign images. Participants in the easy-to-hard condition showed modest advantages both in the acquisition and retention of the melanoma diagnosis skills, but neither scheduling condition exhibited a gross advantage. The Ease values of the items predicted categorization accuracy after, but not before training, suggesting that the Ease algorithm is a promising tool for optimizing medical training in visual categorization.

Comparison of five commonly used automated susceptibility testing methods for accuracy in the China Antimicrobial Resistance Surveillance System (CARSS) hospitals.

ObjectiveThe objective of this study was to evaluate the performance of five commonly used automated antimicrobial susceptibility testing (AST) systems in China (Vitek 2, Phoenix, Microscan, TDR, and DL).Materials and methodsTwo “unknown” isolates, S1 (ESBL-producing Escherichia coli) and S2 (KPC-producing Klebsiella pneumoniae), were sent to 886 hospitals in China for identification and AST. Using broth microdilution method (BMD) as gold standard, minimum inhibitory concentrations (MICs) were determined.ResultsMost hospitals (392, 46.1%) used Vitek 2, followed by 16% each for Phoenix, Microscan, and DL systems, and 5.9% (50) used TDR system. MICs of 22 antimicrobials were evaluated for two study isolates plus three ATCC strains. Individual susceptibility results for three ATCC strains (n=1581) were submitted by 780 (91.2%) hospitals. For each AST system, 8.7% (6/69) to 13.0% (33/253) reported MICs outside the expected range for several drugs. For the two study isolates, TDR and DL systems performed the worst in MIC determination and susceptibility categorization of cefazolin and cefepime, while the Microscan system had difficulties in susceptibility categorization for aztreonam and ertapenem. Categorical agreements were >90% for most antimicrobials tested for both the isolates, among which, using BMD, no essential agreements were noted for ampicillin, piperacillin, cefazolin, cefuroxime, ceftriaxone, and trimethoprim/sulfamethoxazole. All AST systems except Vitek 2 showed unacceptable VMEs for cefazolin (S1 and S2) and major errors for ceftazidime, cefepime, and aztreonam (isolate S1), while Vitek 2 showed a high VME rate for cefepime (10.0%) and meropenem (6.2%) for S2.ConclusionNone of the five automated systems met the criteria for acceptable AST performance, but Vitek 2 provided a relatively accurate and conservative performance for most of the antimicrobials.

Hashtag Recommendation Approach Based on Content and User Characteristics

ABSTRACTTwitter has become a popular microblogging service that allows millions of active users share news, emergent social events, personal opinions, etc. That leads to a large amount of data producing every day and the problem of managing tweets becomes extremely difficult. To categorize the tweets and make easily in searching, the users can use the hashtags embedding in their tweets. However, valid hashtags are not restricted which lead to a very heterogeneous set of hashtags created on Twitter, increasing the difficulty of tweet categorization. In this paper, we propose a hashtag recommendation method based on analyzing the content of tweets, user characteristics, and currently popular hashtags on Twitter. The proposed method uses personal profiles of the users to discover the relevant hashtags. First, a combination of tweet contents and user characteristics is used to find the top-k similar tweets. We exploit the content of historical tweets, used hashtags, and the social interaction to build the user profiles. The user characteristics can help to find the close users and enhance the accuracy of finding the similar tweets to extract the hashtag candidates. Then a set of hashtag candidates is ranked based on their popularity in long and short periods. The experiments on tweet data showed that the proposed method significantly improves the performance of hashtag recommendation systems.

Categorization difficulty modulates the mediated route for response selection in task switching.

Conflict during response selection in task switching is indicated by the response congruency effect: worse performance for incongruent targets (requiring different responses across tasks) than for congruent targets (requiring the same response). The effect can be explained by dual-task processing in a mediated route for response selection, whereby targets are categorized with respect to both tasks. In the present study, the author tested predictions for the modulation of response congruency effects by categorization difficulty derived from a relative-speed-of-processing hypothesis. Categorization difficulty was manipulated for the relevant and irrelevant task dimensions in a novel spatial task-switching paradigm that involved judging the locations of target dots in a grid, without repetition of dot configurations. Response congruency effects were observed and they varied systematically with categorization difficulty (e.g., being larger when irrelevant categorization was easy than when it was hard). These results are consistent with the relative-speed-of-processing hypothesis and suggest that task-switching models that implement variations of the mediated route for response selection need to address the time course of categorization.

Physical Androgyny and Categorization Difficulty Shape Political Conservatives’ Attitudes Toward Transgender People

Researchers have recently begun to examine how categorization processes impact social evaluations. In two studies, we examined how sex categorization influences attitudes toward transgender individuals. We found that people evaluated transgender individuals more negatively if they possessed physically androgynous (vs. sex-typical) characteristics because they struggled to identify their sex. These relationships were stronger among political conservatives compared to individuals with more liberal political views. These findings provide new insights for research on attitudes toward gender minorities and for the role of political ideology in social judgments.

On dissociating the neural time course of the processing of positive emotions

Providing evidence for categorical theories of emotion mandates the inclusion of discrete emotion categories beyond the typical six “basic” emotions. Traditional neurophysiological investigations of emotion typically feature the six basic emotions with happiness as the lone positive exemplar. Here we studied how event-related potentials (ERPs) might differentiate between two positive emotional expressions: happiness and pride, and if so, at what time interval. Furthermore, given divergent findings in the ERP literature with respect to viewing emotional expressions, we explicitly examined how task type modulates neurophysiological responses when the same stimuli are viewed. While a continuous electroencephalogram (EEG) was recorded, 20 healthy participants completed two tasks: an implicit task where participants judged whether or not a face featured a brown spot (freckle), and an explicit task where they judged the face as portraying a “happy,” “proud,” or “neutral” expression. Behavioral performance exceeded 90% accuracy on both tasks. In the explicit task, participants responded faster and more accurately for Happy compared to Proud and Neutral expressions. Neurophysiologically, amplitudes for N170, VPP and P250 ERPs differentiated emotional from neutral expressions, but not from each other. In contrast, the late SPW component significantly differentiated Happy and Proud expressions from each other. Moreover, main effects of Task were found for the VPP, P250, LPP and SPW; additionally, Emotion X Task interactions were observed for P250 and SPW. Our data stress that task demands may magnify or diminish neural processing differences between emotion categories, which therefore cannot be disentangled with a single experimental paradigm. Additionally, some ERP differences may also reflect variations in categorization difficulty.

A review of empirical evidence on different uncanny valley hypotheses: support for perceptual mismatch as one road to the valley of eeriness.

The uncanny valley hypothesis, proposed already in the 1970s, suggests that almost but not fully humanlike artificial characters will trigger a profound sense of unease. This hypothesis has become widely acknowledged both in the popular media and scientific research. Surprisingly, empirical evidence for the hypothesis has remained inconsistent. In the present article, we reinterpret the original uncanny valley hypothesis and review empirical evidence for different theoretically motivated uncanny valley hypotheses. The uncanny valley could be understood as the naïve claim that any kind of human-likeness manipulation will lead to experienced negative affinity at close-to-realistic levels. More recent hypotheses have suggested that the uncanny valley would be caused by artificial–human categorization difficulty or by a perceptual mismatch between artificial and human features. Original formulation also suggested that movement would modulate the uncanny valley. The reviewed empirical literature failed to provide consistent support for the naïve uncanny valley hypothesis or the modulatory effects of movement. Results on the categorization difficulty hypothesis were still too scarce to allow drawing firm conclusions. In contrast, good support was found for the perceptual mismatch hypothesis. Taken together, the present review findings suggest that the uncanny valley exists only under specific conditions. More research is still needed to pinpoint the exact conditions under which the uncanny valley phenomenon manifests itself.

Complexity measures and concept learning

The nature of concept learning is a core question in cognitive science. Theories must account for the relative difficulty of acquiring different concepts by supervised learners. For a canonical set of six category types, two distinct orderings of classification difficulty have been found. One ordering, which we call paradigm-specific, occurs when adult human learners classify objects with easily distinguishable characteristics such as size, shape, and shading. The general order occurs in all other known cases: when adult humans classify objects with characteristics that are not readily distinguished (e.g., brightness, saturation, hue); for children and monkeys; and when categorization difficulty is extrapolated from errors in identification learning. The paradigm-specific order was found to be predictable mathematically by measuring the logical complexity of tasks, i.e., how concisely the solution can be represented by logical rules.However, logical complexity explains only the paradigm-specific order but not the general order. Here we propose a new difficulty measurement, information complexity, that calculates the amount of uncertainty remaining when a subset of the dimensions are specified. This measurement is based on Shannon entropy. We show that, when the metric extracts minimal uncertainties, this new measurement predicts the paradigm-specific order for the canonical six category types, and when the metric extracts average uncertainties, this new measurement predicts the general order. Moreover, for learning category types beyond the canonical six, we find that the minimal-uncertainty formulation correctly predicts the paradigm-specific order as well or better than existing metrics (Boolean complexity and GIST) in most cases.

A reappraisal of the uncanny valley: categorical perception or frequency-based sensitization?

The uncanny valley (UCV) hypothesis describes a non-linear relationship between perceived human-likeness and affective response. The “uncanny valley” refers to an intermediate level of human-likeness that is associated with strong negative affect. Recent studies have suggested that the uncanny valley might result from the categorical perception of human-like stimuli during identification. When presented with stimuli sharing human-like traits, participants attempt to segment the continuum in “human” and “non-human” categories. Due to the ambiguity of stimuli located at a category boundary, categorization difficulty gives rise to a strong, negative affective response. Importantly, researchers who have studied the UCV in terms of categorical perception have focused on categorization responses rather than affective ratings. In the present study, we examined whether the negative affect associated with the UCV might be explained in terms of an individual's degree of exposure to stimuli. In two experiments, we tested a frequency-based model against a categorical perception model using a category-learning paradigm. We manipulated the frequency of exemplars that were presented to participants from two categories during a training phase. We then examined categorization and affective responses functions, as well as the relationship between categorization and affective responses. Supporting previous findings, categorization responses suggested that participants acquired novel category structures that reflected a category boundary. These category structures appeared to influence affective ratings of eeriness. Crucially, participants' ratings of eeriness were additionally affected by exemplar frequency. Taken together, these findings suggest that the UCV is determined by both categorical properties as well as the frequency of individual exemplars retained in memory.

Structure-activity Relationship Models for Hazard Assessment and Risk Management of Engineered Nanomaterials

The widespread use of engineered nanomaterials (ENMs) for commercial purposes made human exposure to these materials almost inevitable. Moreover, the number of in vivo and in vitro studies reporting the potential adverse effects of exposure to ENMs is growing rapidly. Consequently, there is an urgent need to understand the interactions between ENMs and biological/environmental systems. Although the need to improve our understanding of the adverse health effects of ENMs has been recognised for some time, it has not been fully met to date. There are many reasons that have caused the hazard assessment of ENMs to fall behind the innovations in nanotechnology such as knowledge gaps exist in the field of nanotoxicology, difficulties in categorization of ENMs for toxicological considerations and uncertainties regarding the evaluation and regulation of potential risks of nanoparticles. The presence of a large number of ENMs with unknown risks has led to increased interest in the use of fast, cost-effective and efficient computational methods for predicting the toxic potential of ENMs. To that end, the potential use of in silico techniques, such as quantitative structure-activity relationship (QSAR), to model the relationship between biological activities and physicochemical characteristics of ENMs is investigated in this paper. The focus of this paper is on defining the current level of knowledge in (Q)SAR modeling of potential hazards of ENMs and demonstrating the use of (Q)SAR to predict the potential risks specific to ENMs with a case study. Moreover, it presents an overview of the (1) existing barriers currently limiting the development of robust nano-(Q)SAR models, (2) the current obstacles to regulatory acceptance of these models and (3) the integration of (Q)SARs into the risk assessment process. The result of this study demonstrated that the use of (Q)SAR modeling approach to model the toxicity of ENMs based on specific structural and compositional features greatly facilitates (1) filling knowledge gaps regarding the effect of specific parameters on the biological activities of ENMs, (2) predicting the potential risks associated with the exposure to ENMs, (3) classifying the ENMs according to their physicochemical properties and potential hazard degree and (4) reducing the risk by modifying ENMs based on the observed correlations between structural features and biological responses.

Linking perception, cognition, and action: psychophysical observations and neural network modelling.

It has been argued that perception, decision making, and movement planning are in reality tightly interwoven brain processes. However, how they are implemented in neural circuits is still a matter of debate. We tested human subjects in a temporal categorization task in which intervals had to be categorized as short or long. Subjects communicated their decision by moving a cursor into one of two possible targets, which appeared separated by different angles from trial to trial. Even though there was a 1 second-long delay between interval presentation and decision communication, categorization difficulty affected subjects’ performance, reaction (RT) and movement time (MT). In addition, reaction and movement times were also influenced by the distance between the targets. This implies that not only perceptual, but also movement-related considerations were incorporated into the decision process. Therefore, we searched for a model that could use categorization difficulty and target separation to describe subjects’ performance, RT, and MT. We developed a network consisting of two mutually inhibiting neural populations, each tuned to one of the possible categories and composed of an accumulation and a memory node. This network sequentially acquired interval information, maintained it in working memory and was then attracted to one of two possible states, corresponding to a categorical decision. It faithfully replicated subjects’ RT and MT as a function of categorization difficulty and target distance; it also replicated performance as a function of categorization difficulty. Furthermore, this model was used to make new predictions about the effect of untested durations, target distances and delay durations. To our knowledge, this is the first biologically plausible model that has been proposed to account for decision making and communication by integrating both sensory and motor planning information.

Response inhibition during perceptual decision making in humans and macaques

Response inhibition in stop signal tasks has been explained as the outcome of a race between GO and STOP processes (e.g., Logan, 1981). Response choice in two-alternative perceptual categorization tasks has been explained as the outcome of an accumulation of evidence for the alternative responses. To begin unifying these two powerful investigation frameworks, we obtained data from humans and macaque monkeys performing a stop signal task with responses guided by perceptual categorization and variable degrees of difficulty, ranging from low to high accuracy. Comparable results across species reinforced the validity of this animal model. Response times and errors increased with categorization difficulty. The probability of failing to inhibit responses on stop signal trials increased with stop signal delay, and the response times for failed stop signal trials were shorter than those for trials with no stop signal. Thus, the Logan race model could be applied to estimate the duration of the stopping process. We found that the duration of the STOP process did not vary across a wide range of discrimination accuracies. This is consistent with the functional, and possibly mechanistic, independence of choice and inhibition mechanisms.

Eye movement in isolated spelling disorder – An analysis using the dual route model of visual word recognition

Abstract The aim of the study is to investigate whether adolescents with isolated spelling disorder face difficulties connected with the functional effectiveness of words' orthographic representations in the mental lexicon, and to determine the nature of such dysfunction. The assumed effectiveness indicator for the function of orthographic representations was the characteristics of eye movements performed in course of assessing the correctness of spelling of words. The main group effect was not found in the eye movement indices. The different patterns of eye movement between poor and good spellers were found in the context of the recognition accuracy and correctness of notation. This indicates that spelling disorder is not a problem of perception and visual attention, nor is it a problem of phonology (proper function of sub-lexical and lexical route). We suggest it could be a symptom of difficulties in coding and perceptual categorization.

Dissociating task difficulty from incongruence in face-voice emotion integration

In the everyday environment, affective information is conveyed by both the face and the voice. Studies have demonstrated that a concurrently presented voice can alter the way that an emotional face expression is perceived, and vice versa, leading to emotional conflict if the information in the two modalities is mismatched. Additionally, evidence suggests that incongruence of emotional valence activates cerebral networks involved in conflict monitoring and resolution. However, it is currently unclear whether this is due to task difficulty—that incongruent stimuli are harder to categorize—or simply to the detection of mismatching information in the two modalities. The aim of the present fMRI study was to examine the neurophysiological correlates of processing incongruent emotional information, independent of task difficulty. Subjects were scanned while judging the emotion of face-voice affective stimuli. Both the face and voice were parametrically morphed between anger and happiness and then paired in all audiovisual combinations, resulting in stimuli each defined by two separate values: the degree of incongruence between the face and voice, and the degree of clarity of the combined face-voice information. Due to the specific morphing procedure utilized, we hypothesized that the clarity value, rather than incongruence value, would better reflect task difficulty. Behavioral data revealed that participants integrated face and voice affective information, and that the clarity, as opposed to incongruence value correlated with categorization difficulty. Cerebrally, incongruence was more associated with activity in the superior temporal region, which emerged after task difficulty had been accounted for. Overall, our results suggest that activation in the superior temporal region in response to incongruent information cannot be explained simply by task difficulty, and may rather be due to detection of mismatching information between the two modalities.