A New Tactile Illusion: Temporal Limits on the Processing of Spatiotemporal Patterns

A novel illusion was observed when 12 tactile point-stimulators arranged in a circle were sequentially activated so that each quadrant was first traced in a clockwise manner, then counterclockwise, and again in a clockwise manner, after which the next quadrant was similarly traced. Under certain temporal conditions this stimulus pattern was experienced as a point moving through an overall circular path but looping inwardly about once per quadrant. The effects of variations in rate of presentation of such stimuli were investigated by having subjects make drawings of their perceptual experiences. Three skin surfaces were used (palm, fingers, and forearm), and all produced similar results except for lower confidence and reliability of drawings made from forearm stimulation. Pattern presentation rate, however, had a consistent and powerful effect, with the looping illusion most frequently observed at rates around 25 pattern points per s and with different perceptual organizations dominating as rates departed widely from this optimum. The illusory perceptual organizations were interpreted as compromises between past and present stimulation necessitated by the relative slowness of tactile processing of spatio-temporal patterns.     

Handedness in a virtual haptic environment: Assessments from kinematic behavior and modeling

This study evaluated hand asymmetries in performance of a dexterous, controlled task under haptic feedback. Participants punctured a virtual membrane with a pushing or pulling movement, using the left or right hand. For pulling movements, the dominant (right) hand exhibited faster average stopping latency and shorter skidding distance. When the kinematic data were fit to a three-phase model previously applied to this task (Klatzky et al., 2013), the right hand exhibited faster force decay attributable to biomechanical factors. Analyses of the aggregated performance measures and model parameters showed that the left and right hands are associated with two different distributions, supporting handedness effects. Furthermore, while the majority of participants expressed right-hand dominance, which was consistent with their self-reported hand preferences, others showed partial or no dominance. This approach could potentially be extended to quantify and differentiate individuals with difficulties in manual behavior due to abnormal motor control (e.g., dyspraxia), progressive deterioration (e.g., Parkinson's syndrome) or improvement (neural regrowth after transplant).     

Behavioral Approach System Sensitivity and Risk Taking Interact to Predict Left-Frontal EEG Asymmetry

The Behavioral Approach System (BAS) hypersensitivity theory of bipolar disorder (BD; Alloy & Abramson, 2010; Depue & Iacono, 1989) suggests that hyperreactivity in the BAS results in the extreme fluctuations of mood characteristic of BD. In addition to risk conferred by BAS hypersensitivity, cognitive and personality variables may play a role in determining risk. We evaluated relationships among BAS sensitivity, risk taking, and an electrophysiological correlate of approach motivation, relative left-frontal electroencephalography (EEG) asymmetry. BAS sensitivity moderated the relationship between risk taking and EEG asymmetry. More specifically, individuals who were high in BAS sensitivity showed left-frontal EEG asymmetry regardless of their level of risk-taking behavior. However, among individuals who were moderate in BAS sensitivity, risk taking was positively associated with asymmetry. These findings suggest that cognitive and personality correlates of bipolar risk may evidence unique contributions to a neural measure of trait-approach motivation. Clinical implications of these findings are discussed.     

Negative affectivity and EEG asymmetry interact to predict emotional interference on attention in early school-aged children

Negative affectivity (NA) is a broad construct that has been associated with the development of psychopathologies, such as anxiety, and with exaggerated attention to threatening stimuli. EEG asymmetry reflects biological individual differences in emotional reactivity that may underlie the association between NA and attention to threat. The present study included a sample of 31 five-seven year olds (M age in months = 74.39, SD = 6.57) to test the hypothesis that greater NA, combined with greater right anterior and posterior asymmetries, predicts increased attention interference following threat stimuli. Children completed an executive attention task which presented task-irrelevant threat (angry) and non-threat (neutral) faces prior to each trial. EEG asymmetry was measured at baseline for anterior, anterior-temporal and posterior scalp regions and child NA was measured via maternal report. As predicted, children showing greater NA and greater right anterior-temporal asymmetry showed more attention interference following angry faces. Additionally, two trend-level effects emerged: children showing greater NA and greater left anterior-temporal asymmetry showed less attention interference following angry faces, and children showing greater NA and greater left posterior asymmetry showed less attention interference, but only following neutral faces. Discussion focuses on the utility of using EEG asymmetry in the study of temperament, attentional biases, and the biological processes by which temperament confers risk for psychopathology.     

贫困损害儿童执行功能的作用机制

贫困儿童往往表现出较差的执行功能,贫困的长期危害甚至持续到成人期。为揭示贫困与儿童执行功能弱化之间的作用机制,已有研究分别从行为、生理和脑层面开展了探索。本文沿着行为-生理-脑的内在联系与思路,系统地梳理了有关单一风险、累积风险、剥夺性风险、适应负荷以及前额叶结构和功能等内在机制的最新研究。最后提出未来研究可以关注贫困对儿童执行功能某些成分的塑造、聚焦剥夺性风险因素的作用机制、开展适应负荷生理机制和相关脑区激活的认知神经机制等方面的研究,以构建行为-生理-脑的整合框架,进一步拓展未来研究领域。     

Intra- and interindividual differences in lateralized cognitive performance and asymmetrical EEG activity in the frontal cortex

The study shows that changes in relative verbal vs. figural working memory and fluency performance from one session to a second session two to 3 weeks apart covary with spontaneously occurring changes of cortical asymmetry in the lateral frontal and central cortex, measured by electroencephalography (EEG) in resting conditions before the execution of tasks. That is, it was examined whether the current state of cortical asymmetry predicts verbal vs. figural performance. The findings complete the circle from studies showing correlations between changes of EEG asymmetry in the lateral frontal cortex and changes of mood to studies showing correlations between changes of mood and changes of relative verbal vs. figural working memory and fluency performance. The study suggests that state-dependent changes of lateralized cortical activity may underlie certain cognitive-emotional interactions observed in previous studies, and supports the assumption of reciprocal influences of specific emotional and specific cognitive processes.     

Hormones and dichotic listening: evidence from the study of menstrual cycle effects

This report presents evidence for changes in dichotic listening asymmetries across the menstrual cycle, which replicate studies from our laboratory and others. Increases in the right ear advantage (REA) were present in women at phases of the menstrual cycle associated with higher levels of ovarian hormones. The data also revealed correlations between hormone levels and behavioural measures of asymmetry. For example, the pre-ovulatory surge in luteinising hormone (LH) was related to a decrease in left ear scores, which comprised a key part of the cycle related shift in asymmetry. Further analysis revealed a subgroup of women who had not reached postovulatory status by days 18-25 of the cycle, as verified by low progesterone levels. These women showed laterality profiles at days 18-25 that looked more like the other women when measured at the periovulatory phase (i.e., days 8-11). Data were combined with those from a previous study to highlight the stability of effects. Results showed a distinct menstrual cycle related increase in asymmetry in the combined sample. This final comparison confirmed the nature of sex differences in dichotic listening as being dependent on hormone status in women.     

赢者诅咒：心理机制、影响因素及应对策略

赢者诅咒是指在拍卖情境中, 竞价者为了获得拍卖品会过高估计其价值, 竞价成功以后当他发现其价值和自己之前的期望不一致时所产生的一种“诅咒”心理。赢者诅咒现象普遍存在于企业的资产拍卖、兼并重组、博彩游戏、投资决策等领域。损失规避和过度自信理论是赢者诅咒的主要心理机制, 而其影响因素主要有竞拍商品价值的不确定性、竞价人数、信息因素和竞价经验等。赢者诅咒的应对策略主要包括联合竞标、信息共享和学习。未来对赢者诅咒的研究需要进一步探讨赢者诅咒的心理机制、研究范式及本土化等问题。     

Visual field differences in visual word recognition can emerge purely from perceptual learning: evidence from modeling Chinese character pronunciation

In Chinese orthography, a dominant character structure exists in which a semantic radical appears on the left and a phonetic radical on the right (SP characters); a minority opposite arrangement also exists (PS characters). As the number of phonetic radical types is much greater than semantic radical types, in SP characters the information is skewed to the right, whereas in PS characters it is skewed to the left. Through training a computational model for SP and PS character recognition that takes into account of the locations in which the characters appear in the visual field during learning, but does not assume any fundamental hemispheric processing difference, we show that visual field differences can emerge as a consequence of the fundamental structural differences in information between SP and PS characters, as opposed to the fundamental processing differences between the two hemispheres. This modeling result is also consistent with behavioral naming performance. This work provides strong evidence that perceptual learning, i.e., the information structure of word stimuli to which the readers have long been exposed, is one of the factors that accounts for hemispheric asymmetry effects in visual word recognition.     

Reorganization of functional and effective connectivity during real-time fMRI-BCI modulation of prosody processing

Mechanisms of cortical reorganization underlying the enhancement of speech processing have been poorly investigated. In the present study, we addressed changes in functional and effective connectivity induced in subjects who learned to deliberately increase activation in the right inferior frontal gyrus (rIFG), and improved their ability to identify emotional intonations by using a real-time fMRI Brain-Computer Interface. At the beginning of their training process, we observed a massive connectivity of the rIFG to a widespread network of frontal and temporal areas, which decreased and lateralized to the right hemisphere with practice. Volitional control of activation strengthened connectivity of this brain region to the right prefrontal cortex, whereas training increased its connectivity to bilateral precentral gyri. These findings suggest that changes of connectivity in a functionally specific manner play an important role in the enhancement of speech processing. Also, these findings support previous accounts suggesting that motor circuits play a role in the comprehension of speech.