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131.
The authors used a predictable, externally cued task-switching paradigm to investigate executive control in a severe closed-head injury (CHI) population. Eighteen individuals with severe CHI and 18 controls switched between classifying whether a digit was odd or even and whether a letter was a consonant or vowel on every 4th trial. The target stimuli appeared in a circle divided into 8 equivalent parts. Presentation of the stimuli rotated clockwise. Participants performed the switching task at both a short (200 ms) and a long (1,000 ms) preparatory interval. Although the participants with CHI exhibited slower response times and greater switch costs, similar to controls, additional preparatory time reduced the switch costs, and the switch costs were limited to the 1st trial in the run. These findings indicate that participants with severe CHI were able to take advantage of time to prepare for the task switch, and the executive control processes involved in the switch costs were completed before the 1st trial of the run ended. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
132.
Vickery Chad D.; Gontkovsky Samuel T.; Wallace Jeanette J.; Caroselli Jerome S. 《Canadian Metallurgical Quarterly》2006,51(1):30
Objective: The current study explored the effectiveness of a group therapy intervention that was focused specifically on self-concept changes following acquired brain injury (ABI). Method: Eighteen individuals in the postacute phase of recovery underwent a 6-week group therapy intervention and were administered a self-concept measure before and after the intervention. Results: Group members showed a significant increase (improvement) in self-concept ratings at the end of the group intervention. Conclusions: Although the results of this study suggest that this intervention may be helpful in improving self-concept following ABI, further exploration is clearly warranted. Future research is needed to investigate the impact of self-concept on emotional adjustment, participation in rehabilitation activities, and functional outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
133.
Rush Beth K.; Malec James F.; Brown Allen W.; Moessner Anne M. 《Canadian Metallurgical Quarterly》2006,51(3):257
Objective: To investigate pre- to postinjury personality change in relation to outcomes following traumatic brain injury (TBI). Design: Prospective analysis of personality ratings, depression, and outcome using multiple regression analyses. Participants: Cohort of 3 clinical trauma groups (mild TBI, moderate-severe TBI, orthopedic injury) and their significant others (SO). Outcome Measures: Independent Living Scale, Vocational Independence Scale, and Mayo-Portland Adaptability Inventory, 1-2 years postinjury. Predictor Variables: Posttraumatic amnesia (PTA); patient and SO NEO Personality Inventory-Revised ratings of preinjury personality taken at 1-2 months postinjury. Results: Personality function was normal for all groups (regardless of rating source) and stable over time. Neuroticism, and specifically depression, accounted for small proportions of variance in functional outcome, beyond PTA. Conclusions: There is little empirical evidence for significant personality disturbance or change up to 2 years post-TBI. Personality and depression contribute modestly to functional outcomes. Results support a distinction between "personality change" and behavior change following TBI. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
134.
Andrzej Buller Michal Joachimczak Juan Liu Katsunori Shimohara 《Artificial Life and Robotics》2005,9(4):197-201
This article presents the key assumptions and current status of the ATR Artificial Brain Project being undertaken to create
Volitron, a device equipped with circuitry that enables the emergence of thought. Such thought would be recognized from Volitron's
specific communication behaviors. The project consists of three complementary themes: psychodynamic architecture, brain-specific
evolvable hardware, and the management of brain-building. The psychodynamic architecture is designed to develop automatically,
driven by “pleasure” coming from discharges of tension gathered in special tension-accumulating devices. Tension-discharging
patterns come first of all from the robot's interactions with its care giver/provider. For the dedicated hardware, we developed
qcellular-automata (qCA), in which groups of uniform logic primitives (q-cells) serve as spike-train-processing units, as well as pulsed para-neural networks (PPNN) that can be evolved, using fuzzified
signals and a genetic algorithm combined with hill climbing, and converted into qCA. The psychodynamic ideas were tested using three robots: Neko, equipped with a pleasure-driven associator, Miao, equipped with MemeStorms (a special working memory in which conflicting ideas fight for access to the long-term memory and
actuators), and Miao+, whose brain is equipped with a growing neural network.
This work was presented in part at the 9th International Symposium on Artificial Life and Robotics, Oita, Japan, January 28–30,
2004 相似文献
135.
本文从生物膜和二十碳酸衍生物两方面论述了α-亚麻酸的必需性,缺乏N-3多烯酸,如α-亚麻酸及二十二碳六烯酸(DHA),降低视网膜和大脑的DHA水平,视觉敏锐度降低,智力下降;α-亚麻酸的摄入提高组织20:5N-3浓度,调节二十碳酸衍生物生物活性物质的生成,抗凝血,扩张血管,抗炎症等功用,对正常的生理活动起着重要的作用,是人体和动物的必需脂肪酸。α-亚麻酸的需求量为0.5%~1.2%(能量)。 相似文献
136.
137.
报道了在妊娠期以单次腹腔注入氚水,宫内受到累积剂量分别为0、0.05、0.10和0.30Gyβ射丝辐射后,对雄性仔鼠行为、学习及记忆能力的影响。研究发现0.10Gy以上剂量组对旷场行为,跳台学习及记忆能力、食物迷宫、水迷宫和孔板探究等多项测试指标均有影响,表现为早期兴奋性增强、晚期抑制及学习记忆能力的减退。结果提示阈剂量大约在0.05和0.10 Gy之间。 相似文献
138.
There are basically two approaches to the use of psychometric tests in the detection of "brain damage": the first is centred around a view of regional equipotentiality of brain functioning and the second around a unitary view of brain functioning. The former was explored in an earlier paper in this journal (Rubino, 1970). The latter approach is explored here in terms of the utility of three well-known tests: the Bender Gestalt, the Benton Visual Retention Test, and the Graham Kendall Memory for Designs. The influence of such factors as age, diagnoses, hit-rates, etc., are briefly discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
139.
140.
Reviews the book, A Triune Concept of the Brain and Behaviour by Paul D. MacLean, edited by T. J. Boag and D. Campbell. This volume contains the three Hincks Memorial Lectures given by Paul D. MacLean at Queen's University, Kingston, Ontario together with a number of supporting papers. The lectures were given in 1969 but not published until four years later. MacLean first presents an evolutionary view of the brain as having developed in three stages with each stage being superimposed upon the previous one. The scope of MacLean's discourse is very wide and, as is common in lectures of this type, rather speculative. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献