Suppression of electroencephalogram Δ power density during non-rapid eye movement sleep as a result of a prolonged cognitive task prior to sleep onset

The effects of a prolonged cognitive task prior to sleep onset on subsequent sleep patterns were examined in 14 healthy subjects who were randomly assigned to two conditions. Those assigned to a working condition were asked to engage in a prolonged cognitive task until close to bedtime (0200 hours), whereas those assigned to a relaxing condition were instructed to perform the same task during the daytime and then to stay awake in a relaxed state until the same bedtime as the work group. Visual scoring of sleep stages showed no significant differences in the amounts of stage 4 and slow wave sleep (stage 3+4) between the two conditions. Power spectrum analysis of sleep electroencephalogram (EEG) revealed that the EEG (0.5–4.0 Hz) power density in the first non-rapid eye movement (REM)-REM sleep cycle was significantly lower following the prolonged cognitive task prior to sleep onset than following the relaxed wakefulness and that the decreased EEG power density in the first sleep cycle was not compensated for during the later part of the sleep. These findings would indicate that the prolonged cognitive task prior to sleep onset may suppress EEG power density during subsequent sleep, suggesting that such a task may interfere with the development of deep non-REM sleep.     

基于神经营养因子探讨经颅直流电刺激对缺血性脑卒中患者的影响

目的 探讨经颅直流电刺激（tDCS）对缺血性脑卒中患者的影响,以及与外周血神经营养因子的相关性。 方法 将40例缺血性脑卒中患者按随机数字表法分为对照组与治疗组,每组20例。2组患者均给予常规药物治疗及康复训练,治疗组在此基础上增加tDCS,强度2.0 mA,每次20 min,每日1次,共14次,对照组给予伪刺激。治疗前及治疗2周后（治疗后）,采用改良Barthel指数（MBI）、简易精神状态量表(MMSE) 、汉密尔顿抑郁量表（HAMD）、抑郁自评量表(SDS)对2组患者进行评估,用ELISA法测定外周血脑源性神经营养因子(BDNF）、神经生长因子(NGF）水平。 结果 治疗前,2组患者MBI、MMSE、HAMD、SDS评分及外周血BDNF、NGF水平比较,差异均无统计学意义（P>0.05）。与组内治疗前比较,2组患者治疗后上述指标均改善（P<0.05）。与对照组比较,治疗组治疗后MBI评分［（68.00±14.81）分］、MMSE评分［（24.85±3.12）分］较高（P<0.05）,HAMD评分［（19.70±2.11）分］较低（P<0.05）,外周血BDNF水平［（108.20±36.96）pg/ml］、NGF水平［（2.90±1.03）pg/ml］较高（P<0.05）。 结论 tDCS可以有效改善缺血性脑卒中患者的认知功能,减轻抑郁症状,提高生活自理能力,其作用机制可能与神经营养因子水平升高有关。     

上肢机器人虚拟情景训练联合头针对脑卒中患者认知功能障碍的影响

目的 探讨上肢机器人虚拟情景训练联合头针对脑卒中后认知功能障碍的影响。 方法 选取脑卒中后认知功能障碍（PSCI）患者90例,按照随机数字表法分为对照组、头针组、综合组,每组30例。对照组给予常规认知和康复训练,头针组给予常规认知和康复训练联合头针治疗,综合组给予常规认知和康复训练、头针治疗和上肢机器人虚拟情景训练。治疗前和治疗4周后（治疗后）,采用简易精神量表（MMSE）和蒙特利尔认知评估量表（MoCA）评估3组患者认知功能,同时采用改良的Barthel指数（MBI）评估3组患者日常生活活动能力。 结果 治疗后,3组患者的MMSE评分、MoCA评分和MBI评分较组内治疗前均明显改善（P<0.05）。头针组治疗后,仅MMSE评分和MBI评分显著优于对照组治疗后（P<0.05）。综合组治疗后的MMSE评分为（22.03±0.96）分,MoCA评分为（15.07±1.48）分,MBI评分为（73.10±8.45）分,均显著优于头针组和对照组治疗后（P<0.05）。 结论 上肢机器人虚拟情景训练联合头针可显著改善PSCI患者的认知功能,并提高其日常生活活动能力。     

口腔修复中高熔铸件浇铸不全的原因浅析及预防

目的:探讨高熔铸件浇铸不全的可能原因。方法:通过对临床85件可摘铸件缺损的初浅分析,总结出浇铸不全的可能原因。结果:高熔铸件浇铸不全的原因有以下7个方面:①铸金量不足;②熔金温度过低;③离心力不够;④铸道布局不当;⑤铸件过薄;⑥高温包埋料透气性差;⑦铸圈温度下降。结论:通过查找原因,总结出预防的方法,对提高高熔铸件修复体的质量有一定的作用。     

银杏叶注射液对实验性大鼠局灶性脑缺血的保护作用

以行为障碍、脑梗死范围、脑含水量、脑组织病理改变为观察指标,研究银杏叶注射液（ＧＢＥ）对大鼠大脑中动脉闭塞所致局部脑缺血的防治作用。结果表明,ＧＢＥ２０、４０ｍｇ／ｋｇ静脉注射可显著降低大鼠脑梗死范围和脑含水量,改善行为障碍。脑组织形态学检查显示,ＧＢＥ４０ｍｇ／ｋｇ组动物脑组织缺血病变较轻。提示ＧＢＥ对局灶性脑缺血具有保护作用。     

Cognitive function in the Caerphilly study: Associations with age,social class, education and mood

Baseline cognitive function was established for a study of pre- symptomatic cognitive decline in 1870 men from the general population aged 55–69 years as part of the third examination of the Caerphilly Study. Cognitive assessment included the AH4, a four choice serial reaction time task, a modified CAMCOG, MMSE, NART and various memory tests. Distributions and relationships with age, social class, education and mood at time of testing are presented for a younger population than has previously been available. Multiple linear regression showed cognitive function to be independently associated with all four factors. The age effect was equivalent to one half of a standard deviation (SD) in CRT and AH4 scores. Only the NART score was not associated with age, supporting the use of NART score as an estimate of pre-morbid IQ. The largest age adjusted differences between men with low and normal mood were for the AH4 (3 points, t=5.6, p<0.0001) and the CAMCOG (2 points, t=5.8, p<0.0001). The smallest age adjusted effect of mood was for the CRT (33ms, t=2.14, p=0.32) and the MMSE (0.4 points, t=2.97, p=0.003). Age, mood and education adjusted social class effects were very large ranging between around 0.5 SD for the CRT, and 1.0 SD for the AH4 and NART, respectively. For educational status age, mood and social class adjusted differences were also substantial with tests for trend showing the largest differences for the NART (t=12, p<0.0001) and modified CAMCOG (t=10.6, p<0.0001) with the smallest differences for the CRT (t=2.73, p=0.006).     

Emboli and Neuropsychological Outcome Following Cardiopulmonary Bypass

The dramatic decline in mortality related to cardiac surgery has resulted in over 330,000 surgeries involving cardiopulmonary bypass (CPB) being performed yearly in the United States. Although few patients die as a result of cardiac surgery, over two thirds of the patients demonstrate evidence of acute neuropsychological dysfunction postoperatively. The potential mechanisms contributing to post-CPB neuropsychological deficits are many, but two major inter-related etiologic factors, hypoperfusion and emboli, are suggested as the probable culprits. If embolism is the cause of the deficits, increasing cerebral perfusion would deliver more emboli and increase the amount and severity of injury. Conversely, if hypoperfusion is the cause of the injury, then decreasing brain blood flow to minimize embolic delivery would increase the likelihood of perfusion injury. By monitoring the carotid arteries of patients undergoing coronary artery bypass graft surgery, we have determined the frequency and quantity of embolic signals that occur during CPB. Although we have not been able to determine the nature of the embolus, gaseous or solid, we have demonstrated a relationship between the overall embolic load and the probability of having NP dysfunction.     

Neurological soft signs in schizophrenia: Assessment and correlates

A German version of the Neurological Evaluation Scale (NES) was administered to 143 schizophrenic patients, 45 of them being severly chronic and disabled. Seventy-eight alcohol-dependent inpatients and 57 healthy volunteers were tested as control groups. Neurological soft signs (NSS) were rated with convincing agreement. Schizophrenic patients are more impaired on all scales than healthy controls. The chronic, severly disabled schizophrenic patients are more impaired compared with the main group of schizophrenic patients and both control groups. A significant patients and alcohol-dependent patients was only found for the subscale Motor Coordination. Compared with healthy controls the alcohol-dependent patients show a higher NES total score. The NES total score was related to the relative width of the third ventricle. Total score and subscales were correlated consistently with the level of cognitive functioning as measured by the Raven Standard Progressive Matrices and various neuropsychological tests presumably sensitive to dysfunctions of the prefrontal cortex. The NSS were related to positive as well as to negative symptoms, the correlations with negative symptoms being confined to items of Cognitive Disorganization. This close association of psychomotor and cognitive dysfunctions may be seen as related to the frequently discussed dysfunctions of the prefrontal cortex or the neurointegrative deficit postulated by Meehl.     

How do normal subjects learn a simple adaptative task: How and why do paranoid schizophrenic patients fail?

Summary The authors studied the behavior of normal subjects and paranoid schizophrenic patients in a simple problem-solving situation. The schizophrenics were divided into two sample groups, one of individuals under treatment and the other of individuals not under treatment.The learning process involved in this problem-solving situation is very similar to an instrumental conditioning, and can be understood by means of the following assumptions: (1) the subjects use decision functions in reacting to the stimuli, although they may be not fully aware of this; (2) learning is the result of successive transformations of these decisions in the course of time; (3) the changes have specific probabilities and are related to (a) those responses which are made to the latest stimuli, and (b) a differential probability for decision functions which were effective, or only interrupted painful reinforcement, or were completely ineffective.In schizophrenics further factors of importance were (1) an inertia factor and (2) the rigidly continued use of unsuccessful or only partially successful decision criteria.The authors used a systems theory based on Galois field theory and a calculus of operators specifying three groups of subjects. A computer program based on these hypotheses was tested in a simulation experiment.The statistical evaluation of the results showed a congruence between the theoretical approach and the experimental data.This work was carried out with financial support from the Institute de Alta Cultura, Lisbon, between 1970 and 1974     

Reversal learning deficits in young monkeys exposed to lead.

The reversal learning capacity of young rhesus monkeys in visual discrimination tasks was examined during daily exposure to dietary lead acetate throughout the first year of life. While not affected in physical development, all lead-treated monkeys showed performance deficits on reversal learning tasks. These deficits were independent of lead-induced changes in motivation. Over a series of problems, the overall learning rate of monkeys with blood lead concentrations in the range of 70-90 microgram/dl was retarded, which resulted partly from a pronounced difficulty in attaining criterion on the first of a series of reversals within a given problem. This latter deficit resulted from an increase in errors, balks, and total trials to criterion on the first reversal. Monkeys exposed to blood lead concentrations of 40-60 microgram/dl required significantly more trials to finish all problems, but did not show the first-reversal deficit. Theoretical implications of these data were discussed.