The neural correlates of orienting to walking direction in 6‐month‐old infants: An ERP study

The ability to detect social signals represents a first step to enter our social world. Behavioral evidence has demonstrated that 6‐month‐old infants are able to orient their attention toward the position indicated by walking direction, showing faster orienting responses toward stimuli cued by the direction of motion than toward uncued stimuli. The present study investigated the neural mechanisms underpinning this attentional priming effect by using a spatial cueing paradigm and recording EEG (Geodesic System 128 channels) from 6‐month‐old infants. Infants were presented with a central point‐light walker followed by a single peripheral target. The target appeared randomly at a position either congruent or incongruent with the walking direction of the cue. We examined infants' target‐locked event‐related potential (ERP) responses and we used cortical source analysis to explore which brain regions gave rise to the ERP responses. The P1 component and saccade latencies toward the peripheral target were modulated by the congruency between the walking direction of the cue and the position of the target. Infants' saccade latencies were faster in response to targets appearing at congruent spatial locations. The P1 component was larger in response to congruent than to incongruent targets and a similar congruency effect was found with cortical source analysis in the parahippocampal gyrus and the anterior fusiform gyrus. Overall, these findings suggest that a type of biological motion like the one of a vertebrate walking on the legs can trigger covert orienting of attention in 6‐month‐old infants, enabling enhancement of neural activity related to visual processing of potentially relevant information as well as a facilitation of oculomotor responses to stimuli appearing at the attended location.     

Working memory in wayfinding-a dual task experiment in a virtual city

This study examines the working memory systems involved in human wayfinding. In the learning phase, 24 participants learned two routes in a novel photorealistic virtual environment displayed on a 220° screen while they were disrupted by a visual, a spatial, a verbal, or—in a control group—no secondary task. In the following wayfinding phase, the participants had to find and to "virtually walk" the two routes again. During this wayfinding phase, a number of dependent measures were recorded. This research shows that encoding wayfinding knowledge interfered with the verbal and with the spatial secondary task. These interferences were even stronger than the interference of wayfinding knowledge with the visual secondary task. These findings are consistent with a dual-coding approach of wayfinding knowledge.     

Sex Differences in Episodic Memory

ABSTRACT— Research shows sex differences in episodic memory. These differences vary in magnitude as a function of the type of material to be remembered. Throughout the life span, verbal episodic-memory tasks yield differences favoring women. In contrast, episodic-memory tasks requiring visuospatial processing result in differences favoring men. There are also sex differences favoring women on episodic-memory tasks requiring both verbal and visuospatial processing and on face-recognition tasks. Thus, there may be a small, general episodic-memory advantage for women—an advantage that can increase by the advantage women have over men in verbal production and can be reversed by the male advantage in visuospatial tasks. In addition, environmental factors affect the magnitude of the sex differences in episodic memory.     

Why might language and motor impairments occur together?

A step‐wise methodology is employed in order to identify common neurological factors underlying motor and language impairments where they occur together. A sample of 15 5–10‐year‐old children with predetermined language impairment was tested comprehensively using the Illinois Test of Psycholinguistic Ability (ITPA) and the Movement Assessment Battery for Children (Movement ABC). On the basis of these tests, only four of the sample were found to have generally poor performance both in psycholinguistic (particularly indexed by problems with visual closure and sound blending) and motor abilities (particularly indexed by manual dexterity problems—bimanual co‐ordination and drawing—and static balance. Further detailed examination of the findings fostered a number of plausible hypotheses to account for this communality. The viability of these different alternatives is discussed. Copyright © 2003 John Wiley & Sons, Ltd.     

分散注意条件下学优生与学困生视空间工作记忆的比较研究

通过控制干扰刺激量 ,研究分散注意对学优生和学困生视空间WM的影响。实验一的结果表明 :在不同干扰条件下 ,学困生视空间WM均比学优生差 ;干扰任务不仅影响学困生视空间WM的加工能力 ,也影响他们的存储能力。这说明学困生不能有效抑制外界干扰可能是他们视空间WM存在缺陷的主要原因之一。实验二的结果表明 :视空间WM有缺陷是各类学困生普遍存在的问题 ;对于学优生来说 ,不同类型学优生视空间WM不同 ,语文学优比数学学优的学生的视空间WM能力更强 ,主要表现在加工功能上。     

Children’s early mental number line: Logarithmic or decomposed linear?

Recently, the nature of children’s mental number line has received much investigation. In the number line task, children are required to mark a presented number on a physical number line with fixed endpoints. Typically, it was observed that the estimations of younger/inexperienced children were accounted for best by a logarithmic function, whereas those of older/more experienced children were reflected best by a linear function. This led to the conclusion that children’s mental number line transforms from logarithmic to linear with age and experience. In this study, we outline an alternative interpretation of children’s performance in a number line task. We suggest that two separate linear representations for one- and two-digit numbers may exist in young children and that initially the integration of these two representations into the place value structure of the Arabic number system is not fully mastered. When testing this assumption in a sample of more than 120 first graders, we observed that the two-linear model consistently provided better fit indexes. We conclude that instead of assuming a transition from logarithmic to linear coding, performance differences could also be accounted for by an improvement in integrating tens and units into the Arabic place value system.     

Presidential speechmaking style: Emotional response to micro-expressions of facial affect

Research considering the effect of Presidential speech making style shows individuals are likely to attend to and be emotionally affected by the facial expressions of leaders, especially those that are inappropriate for the context. In this study we tested how rapid and subtle expressions of facial affect (i.e., expressions of less than one-second, often termed micro-expressions) in speeches by a political leader impacts participants’ emotional state. We do this by removing seven brief expressions (less than one-second) from a nearly twelve minute televised speech by President George H. W. Bush concerning the 1990 commitment of US military in response to Iraq’s invasion of Kuwait. FACS coding identified all these expressions as containing a component of smiling (lip corner puller: AU12), in some cases with the addition of other facial movements (sometimes associated with anger and/or disgust). Experiments carried out on 206 university undergraduates showed emotional state was altered as a result of these micro-expressions when the control (unaltered speech) and experimental group (micro-expressions removed from speech) were compared. Specifically, participants who viewed the micro-expressions felt less threatened and less angry. Thus, facial expression (even very brief micro-expressions) can have a significant impact on the receiver of a political speech.

模拟互变问题解决认知策略的实验研究

本实验通过对模拟互变问题解决认知策略的定性和定量分析,研究认知策略的类型及其信息加工程序。结果表明,存在尝试性策略、分析性策略和直觉性策略三类策略。最佳策略属于分析性策略。     

Coding responses and the generalization of matching to sample in children.

Two experiments studied the conditions of stimulus control necessary for the generalization of relational matching to sample. Matching required the selection of comparison shapes rotated 90 degrees clockwise from the orientation of the corresponding sample. In Experiment 1, five children were taught to: (a) code the orientations of samples, (b) transform sample codings to account for the 90 degree rotation, and (c) repeat the transformed sample coding response to a comparison. High levels of generalization occurred with a set of novel stimuli for which stable sample-coding responses were initially available. In another novel set, where stable sample-coding responses were not initially available, low levels of generalized matching were recorded. Matching performance improved after stable coding responses were trained. In Experiment 2, two children and three adults were trained in a form of the matching task that produced poor generalization despite the presence of stable sample-coding responses. Retraining to modify the stimulus control exerted by these coding responses produced an immediate improvement in generalized matching to sample. Results suggest that the generalization of matching is dependent on structure of stimulus control that the component responses exert on each other.