Comparison of brain mechanisms underlying the processing of Chinese characters and pseudo-characters: an event-related potential study

Most Chinese characters are composed of a semantic radical on the left and a phonetic radical on the right. The semantic radical provides the semantic information; the phonetic radical provides information concerning the pronunciation of the whole character. The pseudo‐characters in the study consisted of different sub‐lexical parts of real Chinese characters and consequently they also had the semantic radical and the phonetic radical. But they were not readable and had no actual meaning. In order to investigate the spatiotemporal cortical activation patterns underlying the orthographic, phonological and semantic processing of Chinese characters, we used event‐related brain potentials (ERPs) to explore the processing of Chinese characters and pseudo‐characters when 14 healthy Chinese college students viewed the characters passively. Results showed that both Chinese characters and pseudo‐characters elicited an evident negative potential peaking around 120 ms (N120), which appeared to reflect initial orthographic distinction and evaluation. Then, Chinese pseudo‐characters elicited a more positive ERP deflection (P220) than did Chinese characters 200–250 ms after onset of the stimuli. It was similar to the recognition potential (RP) and might reflect the integration processes of phonological and semantic processing on the basis of early orthographic information. Dipole source analysis of the difference wave (pseudo‐characters minus characters) indicated that a generator localized in the left temporal‐occipital junction contributed to this effect, which was possibly related to phonological and perceptual–semantic information integration. Between 350–450 ms, a greater negativity (N360) in pseudo‐characters as compared to characters was found over midline fronto‐central scalp regions. Dipole analysis localized the generator of N360 in the right parahippocampal cortex. Therefore, the N360 might be an N400 component and reflect the higher‐level semantic activation on the basis of orthographic, phonological and perceptual–semantic processing.     

Effects of Accelerated Reading Rate on Processing Words' Syntactic Functions by Normal and Dyslexic Readers: Event Related Potentials Evidence

In the present study, the authors examined differences in brain activity, as measured by amplitudes and latencies of event related potentials (ERP) components, in Hebrew-speaking adult dyslexic and normal readers when processing sentence components with different grammatical functions. Participants were 20 dyslexic and 20 normally reading male college students aged 18–27 years. The authors examined the processing of normal word strings in word–by-word reading of sentences having subject-verb-object (SVO) syntactic structure in self- and fast-paced conditions. Data revealed that in both reading conditions, the N100 and P300 ERP components were sensitive to internal processes such as recognition of words' grammatical functions. However, the results revealed that fast-paced reading rate might affect this process, as was reflected in the systematic changes of amplitudes and latencies of both ERP components. In accelerated reading, a significant decrease of latencies and increase of amplitudes in dyslexics were shown. It was also found that influence of fast-paced reading rate was realized in the full usage of the word-order strategy in sentence processing. In turn, this fact confirmed the hypothesis concerning a syntactic processing “weakness” in dyslexia.     

Executive functions and social skills in survivors of pediatric brain tumor

Medical advances have resulted in increased survival rates for children with brain tumors. Consequently, issues related to survivorship have become more critical. The use of multimodal treatment, in particular cranial radiation therapy, has been associated with subsequent cognitive decline. Specifically, deficits in executive functions have been reported in survivors of various types of pediatric brain tumor. Survivors are left with difficulties, particularly in self-monitoring, initiation, inhibition, and planning, to name a few. Another domain in which survivors of pediatric brain tumor have been reported to show difficulty is that of social skills. Parents, teachers, and survivors themselves have reported decreased social functioning following treatment. Deficits in executive functions and social skills are likely interrelated in this population, as executive skills are needed to navigate various aspects of social interaction; however, this has yet to be studied empirically. Twenty-four survivors of pediatric brain tumor were assessed using a computerized task of executive functions, as well as paper-and-pencil measures of social skills and real-world executive skills. Social functioning was related to a specific aspect of executive functions, that is, the survivors' variability in response time, such that inconsistent responding was associated with better parent-reported and survivor-reported social skills, independent of intellectual abilities. Additionally, parent-reported real-world global executive abilities predicted parent-reported social skills. The implications of these findings for social skills interventions and future research are discussed.     

Processing of non-canonical word-order: A case-series on lesion-induced reorganized language and age-effects in typical development

Complex grammatical structures are mastered late in language acquisition. We studied age-effects on performance in object topicalization in 48 typically developing German-speaking participants (aged 8–30 years) and in five patients (children and adolescents) with lesion-induced atypical language representation. Production was tested by a sentence repetition task, comprehension by an acting out task. Three topicalized conditions with differing disambiguation (agreement, case, and case plus agreement) were contrasted with canonical control sentences.     

Executive function outcomes of children with traumatic brain injury sustained before three years

Traumatic brain injury (TBI) is a common cause of disability in childhood. While the outcomes of TBI sustained in school years has been heavily researched, very little is known about the impact of TBI in infants and young children. The aim of this study was to investigate the impact of TBI on executive function (EF) in children who sustained a TBI before 3 years of age. A group of 55 children, 19 with a mild TBI, 16 children with a moderate-severe TBI, and 20 uninjured comparison children participated. The EF of children aged 3 to 6 years were compared using child-based measures of attentional control and information processing. Parents completed questionnaires rating their child's EF. Severity groups differed on the child-based EF measure of attentional control with children with TBI performing below the control group. There were no significant group differences for information processing or parent-rated EF. It appears that children who sustain a TBI before the age of 3 years display impairments in some areas of attentional control 3–4 years postinjury. The findings fit with the existing EF literature for older children.     

心理负荷的评估:基于神经人因学的视角

心理负荷的评估正经历着从传统工效学向神经人因学的变革.EEG、ERPs、fMRI、fNIRS和TCD等神经科学研究技术为这场变革提供了有力的工具.研究发现:在单任务情境下,随着操作者心理负荷的增加,脑电α波活动减弱,θ波活动增强,并且前额皮层血流、左侧额下回血液氧合血红蛋白浓度变化均增加,大脑动脉血流速度也增快;在双任务情境下,随着操作者主任务心理负荷的增加,次任务的N1、新异P3和P3b等ERPs成分波幅降低.依据这些研究成果,学者们利用人工神经网络、支持向量机等模式分类算法实现了对心理负荷的实时在线评估.但是,各种研究技术在敏感性、诊断力、主任务干扰、实施需求、可接受性和信度等方面各有优势与不足.在未来研究中,要注意促进相关技术的融合、提高其可接受性,并充分利用模式识别算法提高其诊断力和敏感性.     

A Controlled Pilot-Outcome Study of Sensory Integration (SI) in the Treatment of Complex Adaptation to Traumatic Stress

This study tested whether sensory integration (SI) treatment combined with psychotherapy would improve symptom outcome over psychotherapy alone in the treatment of complex posttraumatic stress, as measured by the Disorders of Extreme Stress Not Otherwise Specified (DESNOS) clinical construct in a group of 10 adult patients with histories of childhood abuse. DESNOS symptoms were assessed at three time periods (T1, baseline; T2, after experimental group SI treatment; and T3, after wait-list control group SI treatment) using the Structured Interview for Disorders of Extreme Stress (SIDES). The Sensory Learning Program? (SLP), developed by the Sensory Learning Institute of Boulder, Colorado, was used as the SI treatment modality. Results indicated significant differential improvement for the group treated with SLP in SIDES Total Score (T1/T2 and T2/T3), Self Perception (T1/T2 and T2/T3), Affect Regulation (T2/T3), and Alterations in Meaning (T1/T2).     

Us versus them: Understanding the process of race perception with event-related brain potentials

Race is powerful social signal, imbued with a great deal of meaning and capable of affecting a wide range of behaviours and judgements. This review focuses on the use of event-related brain potentials (ERPs) to better understand the process and implications of race perception. Research to date repeatedly demonstrates the speed and automaticity with which racial category membership is encoded. The quick and relatively obligatory encoding of racial ingroup and outgroup distinctions in turn affects a variety of subsequent racially biased behaviours. Such findings not only speak to the close link between social categorization and behaviour, but also have been used to understand how the effects of race perception can be moderated.     

The influence of dimensional overlap on location-related priming in the Simon task

Choice reaction times are shorter when stimulus and response locations are compatible than when they are incompatible as in the Simon effect. Recent studies revealed that Simon effects are strongly attenuated when there is temporal overlap with a different high-priority task, accompanied by a decrease of early location-related response priming as reflected in the lateralized readiness potential (LRP). The latter result was obtained in a study excluding overlap of stimulus location with any other dimension in the tasks. Independent evidence suggests that location-related priming might be present in conditions with dimensional overlap. Here we tested this prediction in a dual-task experiment supplemented with recording LRPs. The secondary task was either a standard Simon task where irrelevant stimulus location overlapped with dimensions of the primary task or a Stroop-like Simon task including additional overlap of irrelevant and relevant stimulus attributes. At high temporal overlap, there was no Simon effect nor was there stimulus-related response priming in either condition. Therefore stimulus-triggered response priming seems to be abolished in conditions of limited capacity even if the likelihood of an S–R compatibility effect is maximized.