动、静态视觉信息在真实世界视觉搜索中的作用

真实环境中的视觉搜索是人和动物赖以生存的重要能力。目前的视觉搜索研究多使用静态的观察者和静止的二维搜索对象, 侧重于探究注意在搜索中的作用; 现有的视觉搜索理论模型主要概括了影响搜索的自上而下的注意因素, 而将自下而上影响因素简单归结为影像显著性, 然而在真实环境中, 观察者或搜索对象是可以运动的, 搜索时可利用的视觉信息包括动态光流和静态影像结构信息。已有的视觉识别研究发现这两种信息相结合可以使观察者准确持久地识别场景、事件和三维结构。在现有视觉搜索理论模型中引入两种视觉信息可以较好还原真实环境中的搜索任务。我们提出研究构想和实验方案,探究利用动、静态视觉信息的视觉搜索过程, 从而完善现有的视觉搜索模型。我们认为充分利用环境信息可以提高搜索效率, 且在视觉搜索训练和智能搜索设计等方面有重要的应用价值。     

Detection and discrimination of optical flow components

Observers viewed animation sequences consisting of random dots, some of which moved coherently in a given direction (signal dots) and the rest of which moved randomly (noise dots). Using forced-choice procedures, detectability of weak signals within noise was measured for translation, rotation, and expansion/contraction. Sensitivity to all motion types was approximately equal, with practiced observers reliably detecting coherent motion at signal levels as low as 4%. Observers were able to identify the motion structure presented on a given trial at signal levels corresponding to the detection threshold, implying that the neural signals supporting detection are labeled for motion type. Results are discussed in the context of hierarchical analysis of optic flow in which all motion types are registered as patterns of activity among neurons comprising a single mechanism.     

The impact of task complexity on information use in multi-attribute decision making

This study presents a process analysis of multi-attribute decision making. The decision problems concerned the selection of the most suitable candidate for a job opening. The problems varied in terms of complexity, i.e. the number of candidates and the number of attributes used to describe these alternatives. Results show that with an increasing number of alternatives, subjects (N = 48) used fewer attributes for the evaluation of alternatives, and made, on average, less references to the alternatives. The type of judgment most often used was absolute dimensional (comparison of an attribute to an absolute standard) and was used more often at the beginning than toward the end of the decision process. Overall, judgments were predominantly positive. The percentage of positive judgments decreased with increasing complexity, and toward the end of the decision process. Significantly more judgments, particularly positive ones, concerned the finally chosen alternative as compared to the rest of the alternatives. Finally, analysis of subjects' usage of decision rules revealed that increasing the number of alternatives resulted in an increasing use of elimination strategies. Implications of these findings for the design of decision aids will be discussed.     

Perceiving versus inferring movements to understand dynamic events: The influence of content complexity

ObjectivesWhat type of visual presentation is best in helping learners to understand the functioning of a dynamic system and under what conditions? This study investigated the effect of content complexity on perceived cognitive load and performance resulting from studying depicted movements of team play either in an explicit manner (animation) or via arrow symbols (static diagram).DesignA 2 (treatment: diagram vs. animation) × 2 (content complexity: low vs. high) between subjects design was adopted in the experiment.MethodsForty-eight university students were randomly assigned to the four study conditions and required to perform a reconstruction test and rate their perceived cognitive load following the study phase.ResultsData analyses revealed that for low-complexity content, participants exposed to the animation treatment learned more efficiently – based on the combination of learning and cognitive load scores – than those exposed to the diagram treatment. On the other hand, for high-complexity content, participants exposed to the diagram treatment learned more efficiently than those exposed to the animation treatment.ConclusionThe findings stress the importance of considering the task complexity factor when designing and presenting instructional materials to learners.     

Risk strategy under task complexity: a multivariate analysis of behaviour in a naturalistic setting

This study complements the existing literature on decision-making processes and outcomes in complex settings by exploring the impact of different types of complexity on risk strategies in a naturalistic setting. The study analyses a large sample of decisions made by individuals in UK offcourse betting markets, a fertile environment for observing both a variety of risk strategies and a range of task complexities. Specifically, the investigation focuses on the comparative impacts of complexity defined in terms, respectively, of alternatives and attributes. The results suggest that the risk strategy employed is affected by task complexity. Complexity does not affect the size of risk accepted but alternative- and attribute-based complexity together influence the propensity to accept greater degrees of risk. In addition, the effect of attribute-based complexity on risk taking appears to be modified by the use of risk-hedging strategies. The results are observed to corroborate some earlier work on decision process and outcome; where differences with earlier findings are identified, some possible explanations are offered. © 1998 John Wiley & Sons, Ltd.     

Young children combine sensory cues with learned information in a statistically efficient manner: But task complexity matters

Human adults are adept at mitigating the influence of sensory uncertainty on task performance by integrating sensory cues with learned prior information, in a Bayes‐optimal fashion. Previous research has shown that young children and infants are sensitive to environmental regularities, and that the ability to learn and use such regularities is involved in the development of several cognitive abilities. However, it has also been reported that children younger than 8 do not combine simultaneously available sensory cues in a Bayes‐optimal fashion. Thus, it remains unclear whether, and by what age, children can combine sensory cues with learned regularities in an adult manner. Here, we examine the performance of 6‐ to 7‐year‐old children when tasked with localizing a ‘hidden’ target by combining uncertain sensory information with prior information learned over repeated exposure to the task. We demonstrate that 6‐ to 7‐year‐olds learn task‐relevant statistics at a rate on par with adults, and like adults, are capable of integrating learned regularities with sensory information in a statistically efficient manner. We also show that variables such as task complexity can influence young children's behavior to a greater extent than that of adults, leading their behavior to look sub‐optimal. Our findings have important implications for how we should interpret failures in young children's ability to carry out sophisticated computations. These ‘failures’ need not be attributed to deficits in the fundamental computational capacity available to children early in development, but rather to ancillary immaturities in general cognitive abilities that mask the operation of these computations in specific situations.     

The sound of motion in spoken language: visual information conveyed by acoustic properties of speech

Language is generally viewed as conveying information through symbols whose form is arbitrarily related to their meaning. This arbitrary relation is often assumed to also characterize the mental representations underlying language comprehension. We explore the idea that visuo-spatial information can be analogically conveyed through acoustic properties of speech and that such information is integrated into an analog perceptual representation as a natural part of comprehension. Listeners heard sentences describing objects, spoken at varying speaking rates. After each sentence, participants saw a picture of an object and judged whether it had been mentioned in the sentence. Participants were faster to recognize the object when motion implied by speaking rate matched the motion implied by the picture. Results suggest that visuo-spatial referential information can be analogically conveyed and represented.     

Effects of visual complexity and sublexical information in the occipitotemporal cortex in the reading of Chinese phonograms: a single-trial analysis with MEG

We employ a linear mixed-effects model to estimate the effects of visual form and the linguistic properties of Chinese characters on M100 and M170 MEG responses from single-trial data of Chinese and English speakers in a Chinese lexical decision task. Cortically constrained minimum-norm estimation is used to compute the activation of M100 and M170 responses in functionally defined regions of interest. Both Chinese and English participants’ M100 responses tend to increase in response to characters with a high numbers of strokes. English participants’ M170 responses show a posterior distribution and only reflect the effect of the visual complexity of characters. On the other hand, the Chinese participants’ left hemisphere M170 is increased when reading characters with high number of strokes, and their right hemisphere M170 is increased when reading characters with small combinability of semantic radicals. Our results suggest that expertise with words and the decomposition of word forms underlies processing in the left and right occipitotemporal regions in the reading of Chinese characters by Chinese speakers.     

A descriptive analysis of early word combinations in deaf children's signed utterances

The use of pointing and its place in word combinations and the organization of sentences were examined in children acquiring Japanese Sign Language as a first language. Subjects were three deaf children of signing deaf parents, and were aged from 1 year 9 months to 3 years 1 month at the time of observation. They were observed and videotaped periodically in free play settings. Pointing gestures were observed frequently in the earlier utterances in the development of sign language. It was also found that some pointing was referentially redundant and had a fixed position at the end of a sentence. This suggests that pointing, as well as being used referentially, plays a grammatical role in organizing the sentence.     

The spatial contours of wellbeing: A content analysis of metaphor in academic discourse

Abstract

In thinking and talking about wellbeing, people often deploy spatial metaphors, such as identifying positive and negative affect with ‘up’ and ‘down’ respectively. However, there has not yet been a systematic investigation of how wellbeing is represented through metaphor. To shed light on this topic, a content analysis was conducted of spatial metaphors in academic discourse on wellbeing, focusing on recent editions of two leading journals, the Journal of Positive Psychology, and the British Journal of Clinical Psychology. Across 28 papers, 54 spatial metaphors were identified, grouped into four main categories: verticality; horizontality; configuration; and dynamism. Above all, wellbeing is associated with interior expansiveness, with positive valence usually attaching to vertical metaphors of height and depth, horizontal metaphors of width and breadth, and configuration metaphors of size and growth. The analysis thus offers valuable insights into the subjective dynamics of wellbeing.     

A cross-sequential analysis of developmental differences in speed of visual information processing

Development of processing speed was examined in three backward masking studies. The first verified the central nature of backward masking for children aged 8 and 11 years and for adults. The second suggested that task requirements were equivalent for children similar to those in Study 1, and that age differences in performance were not attributable to nonprocessing variables. The main cross-sequential study estimated speed of processing in 80 children (approximately 6 years to 13 years) and young adults using an inspection time task. Target exposure duration was varied to establish the time required to achieve a high level of discriminative accuracy. Estimates of processing speed increased until about 11-13 years of age; beyond this, the trend was less obvious, and it is possible that inspection time asymptotes at around the onset of adolescence. Performance improvement after 1 year could not be explained as resulting from practice since improvement among controls over a period of 2 weeks was significantly less. Correlations between estimates of inspection time made up to 2 years apart found the measure to be reliable.     

Locus of control and the flow experience: An experimental analysis

The present research addresses the notion that the compatibility of skills and task demands involved in a given activity elicits a flow experience that renders the respective activity rewarding. The study employed an experimental paradigm to document the causal impact of skills–demands compatibility on the emergence of flow and revealed that participants characterized by a strong internal locus of control (LOC) were most sensitive to the manipulation of skills–demands compatibility and experienced flow under conditions of a fit of skills and task demands, whereas individuals with a weak internal LOC did not enter the state of flow. In line with previous findings, this suggests that distinct personality attributes are of critical relevance for the experience of flow to emerge. Copyright © 2008 John Wiley & Sons, Ltd.     

Autoshaping in the rat: The effects of localizable visual and auditory signals for food

Two experiments investigated autoshaping in rats to localizable visual and auditory conditioned stimuli predicting response-independent food. In Experiment 1 considerable conditioned-stimulus approach behavior was generated by a localizable visual conditioned stimulus that was situated approximately 35 cm from the food tray. Using the same apparatus in Experiment 2 we found that the conditioned-stimulus approach was generated only to a visual conditioned stimulus and not to a localizable auditory conditioned stimulus even though subjects (1) could discriminate presentations of the auditory conditioned stimulus, (2) had associated it with food, (3) could localize it, and (4) would approach the auditory stimulus if this behavior constituted an instrumental response to food. The predominant conditioned responses to the auditory stimuli were goal tracking (entering the food tray) and orienting towards the food-paired conditioned stimulus by head turning and rearing and turning. These results imply that rats do not invariably approach a localizable appetitive Pavlovian conditioned stimulus but that stimulus-approach responses depend on the nature and modality of the conditioned stimulus.     

Semaphoring in an earless frog: the origin of a novel visual signal

Social communication in anuran amphibians (frogs and toads) is mediated predominantly by acoustic signals. Unlike most anurans, the Panamanian golden frog, Atelopus zeteki, lacks a standard tympanic middle ear and appears to have augmented its communicatory repertoire to include rotational limb motions as visual signals, referred to here as semaphores. The communicatory nature of semaphoring was inferred from experimental manipulations using mirrored self-image presentations and nonresident introductions. Male frogs semaphored significantly more when presented with a mirrored self-image than with a nonreflective control. Novel encounters between resident males and nonresident frogs demonstrated that semaphores were used directionally and were displayed toward target individuals. Females semaphored frequently and this observation represents a rare case of signaling by females in a typically male-biased communicatory regime. Semaphore actions were clearly linked to a locomotory gait pattern and appear to have originated as an elaboration of a standard stepping motion. Received: 19 March 1998 / Accepted after revision: 25 July 1998     

Integration of weight and distance information in young children: The role of relational complexity

Young children's integration of weight and distance information was examined using a new methodology that combines a single-armed apparatus with functional measurement. Weight and distance values were varied factorially across the item set. Children estimated how far the beam would tilt when different numbers of weights were placed at different distances from the pivot. There was a developmental progression from non-systematic responding (3-year-olds) to responding based on a single variable, usually weight (4-year-olds) to responding based on integration of weight and distance (5-, 6- and 7-year-olds). Individual analyses revealed additive and multiplicative integration rules in children aged from 5 years. Weight–distance strategy complexity increased with age and was associated with better performance on independent measures of relational processing, especially the more complex items. Thus weight–distance integration involves processing of complex relational information. The findings enhance the explanatory power of Relational Complexity theory as a domain-general approach to cognitive development.     

Expertise reversal effect in a pen-tablet-based learning environment: The role of learningcentered emotions in the interplay between learner expertise and task complexity

The study investigated interactions between learner expertise and task complexity evaluated from both cognitive and affective perspectives. One hundred and seventy-three students, both novices and advanced learners, were asked to learn Japanese writing in a pen-tablet-based digital learning environment with varying task complexity levels. Cognitive load and learning-centred emotions were measured at intervals during learning, while writing performance was monitored by runtime tracking. Results indicated that while advanced learners performed better than novices across the range of task complexity, the moderate task complexity was shown to be superior in enhancing performance for both levels of expertise. Results for learning-centred emotions showed that advanced learners reported lower enjoyment and higher frustration when completing the low complexity task, whereas the moderately complex task was reported to be the most enjoyable and less frustrating for these learners. No significant difference in emotions was found across levels of task complexity for novices. Finally, a constructed composite indicator of cognitive-affective efficiency of instructional conditions showed a significant interaction between levels of learner expertise and task complexity primarily caused by affective factors.     

Perceptual tuning and conscious attention: Systems of input regulation in visual information processing

Literature is reviewed in support of very early perceptual input regulation which can be based on higher-order conceptual or structural stimulus properties. This learning-dependent perceptual tuning takes two forms: preconscious orientation, which operates automatically in the processing of most visual information and can be observed as a strong tendency to parse scenic information in terms of conceptually meaningful distinctions, and temporary tuning, in which perceptual biases are modified on a task-specific basis with respect to either scenic information or stimuli whose conceptual properties are arbitrary or conventional such as words as opposed to nonsensical letter strings. Perceptual tuning is contrasted with conscious attention, which is primarily a task selector rather than an input selector.     

Efficiency of visual information processing in children at-risk for dyslexia: habituation of single-trial ERPs

To investigate underlying learning mechanisms in relation to the development of dyslexia, event-related potentials to visual standards were recorded in five-year-old pre-reading children at-risk for familial dyslexia (n=24) and their controls (n=14). At the end of second grade the children aged 8 years were regrouped into three groups according to literacy level and risk factor. Single-trial analyses revealed N1 habituation in the normal-reading controls, but not in the normal-reading at-risks, and a N1 amplitude increase in the group of poor-reading at-risks and poor-reading controls. No P3 habituation was found in either group. The normal-reading at-risk group exhibited the longest N1 and P3 latencies, possibly compensating for their reduced neuronal activity during initial information extraction. In contrast, the poor-reading group only showed prolonged P3, and their increase in (initial small) N1 amplitude together with normal N1 latencies, suggests inefficient processing in an early time window, which might explain automatisation difficulties in dyslexic readers.     

Non-verbal IQ is correlated with visual field advantages for short duration coherent motion detection in deaf signers with varied ASL exposure and etiologies of deafness

Studies have reported a right visual field (RVF) advantage for coherent motion detection by deaf and hearing signers but not non-signers. Yet two studies [Bosworth R. G., & Dobkins, K. R. (2002). Visual field asymmetries for motion processing in deaf and hearing signers. Brain and Cognition, 49, 170-181; Samar, V. J., & Parasnis, I. (2005). Dorsal stream deficits suggest hidden dyslexia among deaf poor readers: Correlated evidence from reduced perceptual speed and elevated coherent motion detection thresholds. Brain and Cognition, 58, 300-311.] reported a small, non-significant RVF advantage for deaf signers when short duration motion stimuli were used (200-250 ms). Samar and Parasnis (2005) reported that this small RVF advantage became significant when non-verbal IQ was statistically controlled. This paper presents extended analyses of the correlation between non-verbal IQ and visual field asymmetries in the data set of Samar and Parasnis (2005). We speculate that this correlation might plausibly be driven by individual differences either in age of acquisition of American Sign Language (ASL) or in the degree of neurodevelopmental insult associated with various etiologies of deafness. Limited additional analyses are presented that indicate a need for further research on the cause of this apparent IQ-laterality relationship. Some potential implications of this relationship for lateralization studies of deaf signers are discussed. Controlling non-verbal IQ may improve the reliability of short duration coherent motion tasks to detect adaptive dorsal stream lateralization due to exposure to ASL in deaf research participants.