Unsupervised categorization with a child sample: category cohesion development

Studies into categorization have demonstrated that the ability to form concepts is an essential ability in cognitive development. For example, before a decision about anything can be made, firstly category concepts need to be acquired in order to make efficient decisions about that situation. The present study explored a particular type of category learning, not previously explored in this particular context – unsupervised categorization with 16 items and two dimensions, and comparing specifically children vs. adults. Previous studies have typically focused on simpler designs such as three items of two dimensions in the triad tasks, or a greater number of dimensions but with much fewer items per category in other unsupervised settings. This study investigated unsupervised categorization with two levels of task difficulty, and compared two different populations, children and adults. The findings revealed that adults performed better for the easy condition but there was no difference between these groups for the more difficult category task. The findings also revealed that unsupervised categorization in more complex settings result in more one dimensional sorting, for both children and adults. The results are discussed in the context of unsupervised categorization development abilities in children.     

Four meanings of “categorization”: A conceptual analysis of research on person perception

It is widely assumed that people tend to “categorize” other people. However, the term “categorization” has been used with qualitatively different underlying definitions in the person perception literature. We present a conceptual analysis in which we disentangle four existing definitions: (a) categorization as representing, (b) categorization as dichotomizing, (c) categorization as organizing, and (d) categorization as grouping. Subsequently, we show that seemingly antagonistic viewpoints in the literature may be reconciled by disentangling these definitions. Furthermore, we argue that disentangling these definitions is vital for theoretical interpretations of (past and future) empirical findings. Overall, our work aims to contribute to the clarity of person perception theories, provide novel perspectives on existing debates, and serve as a stepping stone for more differentiated models of person perception.     

Psychological Essentialism at the Explicit and Implicit Levels: The Unique Status of Social Categories

Psychological essentialism refers to a naive theory concerning fundamental elements that bring a category into its existence. The present study examined the structure of this lay theory as well as its implicitness, with a special focus on social categories. In Study 1, Japanese college students rated a number of categories that were natural‐kind, social, or human artifacts, in terms of different elements of essentialist beliefs. A factor analysis revealed that entitativity and naturalness are the common underlying dimensions across these category domains. We also identified some natural‐kind and human artifact categories that can be used as two extreme referent points for the examination of naturalness perceived in a whole array of social categories. Study 2 assessed implicit and automatic judgments on naturalness using a go/no‐go task, and compared them to explicit judgments. Unlike natural kinds and artifacts, social categories were essentialized to a greater extent at the implicit level. These results suggest a dual process of intuitive and deliberate cognition, particularly involving social categories, with implications concerning the bases of stereotypes and prejudices.     

Altered visual and somatosensory feedback affects gait stability in persons with multiple sclerosis

Persons with multiple sclerosis (PwMS) often report problems due to sensory loss and have an inability to appropriately reweight sensory information. Both of these issues can affect individual’s ability to maintain stability when walking under challenging conditions. The purpose of the current study was to determine how gait stability is adapted when walking under challenging sensory conditions where vision and somatosensation at the feet is manipulated. 25 healthy adults and 40 PwMS (15 fallers, 25 non-fallers) walked on a treadmill at their preferred normal walking speed under 3 conditions: normal walking, altered vision using goggles that shifted visual field laterally, and altered somatosensation using shoes with compliant foam soles. Inertial measurement united recorded acceleration at the lumbar and right ankle, and acceleration variability measures were calculated including root mean square (RMS), range, sample entropy (SaEn), and Lyapunov exponents (LyE). A gait stability index (GSI) was calculated using each of the four variability measures as the ratio of lumbar acceleration variability divided by foot acceleration variability in the frontal and sagittal planes. The sagittal and frontal GSI_RMS were larger in the somatosensory condition compared to the normal and visual conditions (p < 0.001). The frontal GSI_SaEn was greater in the visual condition compared to the somatosensory condition (p = 0.021). The frontal and sagittal GSI_LyE was greater in the somatosensory condition compared to the normal and visual conditions (p < 0.002). The current study showed that HC, MS non-fallers and MS fallers largely adapted to altered sensory feedback during walking in a similar manner. However, MS faller subjects may be more reliant on visual feedback compared to MS non-fallers and HC subjects.     

Multiple causal pathways in attention-deficit/hyperactivity disorder – Do emerging executive and motivational deviations precede symptom development?

The multiple causal pathways model on the etiology of attention-deficit/hyperactivity disorder (ADHD) is well established. However, developmental implications of the model are not yet sufficiently analyzed. The model implies that critical neural and neuropsychological deviations from normative development precede secondarily developing ADHD symptoms. Cognitive, “cool” inhibitory control (CIC) and reward-related, “hot” functions (RRF) are regarded as neuropsychological basic deficits that indicate independent causal pathways. Both functions involve top-down control networks that undergo major normative developmental changes in the preschool period. We formalized the following assumptions in a path model: (a) CIC and RRF predict change in ADHD symptoms in the preschool period, (b) the reverse is not true, and (c) CIC and RRF independently contribute to this prediction. A community-based sample of 125 (71 boys) preschoolers was assessed at at age 4 and 5 years. At each assessment wave, CIC and RRF were measured by a battery of age-appropriate valid tasks. ADHD symptoms were measured by a clinical parent interview. Evaluation of model fit using manifest maximum likelihood parameter estimation clearly supported the hypothesized path model while controlling for gender of child and maternal education level. Thus, regarding the basic deficits of CIC and RRF, the results add evidence on the developmental implications of the multiple causal pathways model. Our findings point to the potential significance of these early emerging characteristics as indicators of risk and as targets for preventive interventions.     

Semantic segmentation via highly fused convolutional network with multiple soft cost functions

Semantic image segmentation is one of the most challenging tasks in computer vision. In this paper, we propose a highly fused convolutional network, which consists of three parts: downsampling, fused upsampling and multiple predictions. We adopt a VGG-net based downsampling structure, followed by multiple steps of upsampling. Feature maps in each pair of corresponding pooling layers and unpooling layers are combined. We also bring out multiple pre-outputs, each is generated from an unpooling layer by a one-step upsampling operation. Finally, we concatenate these pre-outputs to get the final output. As a result, our proposed network makes high use of the feature information by fusing and reusing features in low layers. In addition, when training our model, we add multiple soft cost functions on pre-outputs and the final output. In this way, we can reduce the loss reduction in backpropagation. We evaluate our model on three public segmentation datasets: CamVid, PASCAL VOC, and ADE20K. We achieve considerable segmentation performance on PASCAL VOC dataset and ADE20K dataset. Especially on CamVid dataset, we achieve state-of-the-art performance.     

社会分类的概念、线索及影响机制

作为社会认知的基本过程和重要途径,社会分类对预测刻板印象和群际感知、减少多元文化群体中的关系冲突、促进推理与决策以及指导社会关系推断等都有重要作用。人们进行社会分类的线索可以概括为明显线索和模糊线索、自然线索和社会线索以及静态线索和动态线索。社会分类会受到分类对象、情境和感知者等的作用,同时对人们认知、情绪、情感和行为等产生一系列影响。未来可以基于跨文化和发展视角探讨社会分类的线索偏向、潜在机制及立足本土文化检验社会分类的影响及干预策略。     

Impaired sequential and partially compensated probabilistic skill learning in Parkinson's disease

The striatal dopaminergic dysfunction in Parkinson's disease (PD) has been associated with deficits in skill learning in numerous studies, but some of the findings remain controversial. Our aim was to explore the generality of the learning deficit using two widely reported skill learning tasks in the same group of Parkinson's patients. Thirty-four patients with PD (mean age: 62.83 years, SD: 7.67) were compared to age-matched healthy adults. Two tasks were employed: the Serial Reaction Time Task (SRT), testing the learning of motor sequences, and the Weather Prediction (WP) task, testing non-sequential probabilistic category learning. On the SRT task, patients with PD showed no significant evidence for sequence learning. These results support and also extend previous findings, suggesting that motor skill learning is vulnerable in PD. On the WP task, the PD group showed the same amount of learning as controls, but they exploited qualitatively different strategies in predicting the target categories. While controls typically combined probabilities from multiple predicting cues, patients with PD instead focused on individual cues. We also found moderate to high correlations between the different measures of skill learning. These findings support our hypothesis that skill learning is generally impaired in PD, and can in some cases be compensated by relying on alternative learning strategies.     

群际威胁：影响因素与减少策略

群际威胁是增强消极刻板印象和偏见的重要因素, 甚至可以导致群际冲突或暴力。影响群际威胁的因素包括个体的感知与经验、群体特征、社会政策和法规等。通过改变社会分类, 模糊群际边界, 并创造群际接触的机会, 能够增加群际认同感, 降低群际威胁感, 减少群际偏见, 促进积极的群际关系。今后的研究需在不同的社会环境中完善群际威胁的理论模型, 并探索相关变量相互作用的内在机制, 为促进和改善群际关系提供理论依据。