教与学的大脑：人际神经科学助推教育研究

如何从神经生理层面刻画教育活动的人际互动模式和动态性是教育神经科学面临的一个重要挑战。人际神经科学视角为其提供了可能的解决途径; 这一新兴的视角通过记录和分析进行同一认知活动时两人或多人大脑活动之间的关联, 来揭示大脑活动的群体模式。目前, 人际神经科学方法已被应用于教育研究, 例如监控教学过程、预测教学效果和识别教学影响因素, 相应的研究成果对教育活动具有重要启示。未来的研究者可以更多地关注不同学习水平的学生大脑的互动机制及人际神经科学方法应用于技能教学及线上教学评估的巨大潜力。     

自发性知觉经络反应中产生刺麻感和积极情绪的原因

自发性知觉经络反应(autonomous sensory meridian response,ASMR)是指在特定的视听刺激下,某些个体(ASMR敏感个体)在头皮后部、颈部乃至全身体验到一种令人极度愉快和放松的刺麻感的现象。其中,刺麻感的产生可能是个体大脑中负责感觉和肌肉运动的脑区高度激活引起的; 而与情绪和奖赏有关脑区的高度激活以及心率和呼吸频率的下降可能是产生愉快和放松感的重要原因。相比普通个体,ASMR敏感个体具有较高的神经质、共情特质、感觉受暗示性和特质正念。这可能说明ASMR敏感个体的感觉敏感性较高,情绪稳定性较弱,且比较关注自己身体的内外感受。这些个性特质可能导致ASMR敏感个体对某些视听刺激中所包含的一些感觉和情绪信息更加敏感,对其反应也更加强烈。目前,ASMR已经被用于抑郁,压力,失眠和慢性疼痛等的临床治疗以及商业广告之中。但ASMR可能会干扰个体的执行功能,在认知控制需求较高的情景下应尽量避免接触ASMR刺激。     

小学生喜好的外在奖赏及其运用

采用问卷调查法 ,以杭州市三所小学 3 1 8名小学生为被试 ,考察了他们对目前学校常用的 2 0种奖项的喜好特点。目的在于揭示这些奖项对小学生的潜在意义 ,为教师运用外在奖赏激励学生学习提供依据。结果表明 :(1 )小学生最喜欢社会认同类 ,其次是特权类 ,最后是学校奖项与零食类奖赏。他们最喜欢的前五种奖赏是 :书、奖状、好分数、玩电脑、去图书馆看书。 (2 )小学生在喜好的奖赏及其结构特点上均存在年级与性别差异。     

Visual aspects of centrally elicited attack behavior in the cat: “Patterned reflexes” associated with selection of and approach to a rat

It has been previously suggested that the electrical brain stimulation which elicits quiet-biting attack in the cat actively affects the way the central nervous system processes visual and tactile information concerned with the reflexes involved in the terminal aspects of attack. In order to examine the effects of brain stimulation on a nonterminal aspect of attack – the stimulated cat's selection of and approach to a rat – cats were implanted with attack-eliciting electrodes in both the lateral hypothalamus and the midbrain ventral tegmental area. These cats were then tested in an 8-ft-long cage, one end of which was divided into three, 2-ft-long parallel compartments, whose openings faced the end of the cage from which the cat commenced its approach. An anesthetized rat was placed at the back of one compartment, a bowl of food at the back of another compartment, and the third compartment contained no object. It was found in the first experiment that the attack elicited by nearly all electrodes was selectively directed at the rat. However, the success of the cat in finding the compartment containing the rat varied dramatically for different electrodes in the same cat. Further, these differences were stable and did not change as the cat gained experience with the task. The results suggested that the stimulation of different brain sites in the same cat differentially affected the visual neural mechanisms involved in guiding a cat to a rat. Previous studies have also suggested that the effects of brain stimulation which elicits quiet-biting attack are largely lateralized to the side of the brain stimulated. In order to determine if the effects of stimulation on the neural mechanisms mediating the visually guided approach of a cat to a rat were also lateralized, attempts were made in a second experiment to disrupt the visual input to one side of the brain by unilaterally transecting the optic tract. It was found that this manipulation interfered with the visually guided selective approach to a rat, if the cat was stimulated through hypothalamic or mid-brain electrodes ipsilateral to the optic tract transection, but not if the hypothalamic or midbrain stimulation was on the contralateral (visually intact) side of the brain. However, any final interpretation of the results was confounded by the finding in all of these cats of a complex syndrome of neglect of all contralateral sensory information.     

Impairment in the control of coupled cyclic movements of ipsilateral hand and foot after total callosotomy

Integrity of both cerebral hemispheres is required to control in-phase or anti-phase coupling of ipsilateral hand and foot oscillations, as shown by the impairment of these tasks when performed on the healthy side of hemiplegic patients. On this basis, coupling of hand–foot movements was analysed in a right-handed subject (ME) who underwent a total resection of the corpus callosum. Oscillations of the prone hand and foot, paced by a metronome at different frequencies, as well as EMG activity in extensor carpi radialis (ECR) and tibialis anterior (TA) muscles were analysed by measuring the average phase difference between the hand and foot movements and EMG cycles.

ME performed in-phase movements (right-hand extension coupled to right-foot dorsal flexion) at frequencies up to 3 Hz, though the hand cycle progressively lagged the foot cycle as the frequency increased. At 3 Hz the hand lag reached −142° (as compared to about 25° in healthy subjects). The lag increased even further after application of an inertial load to the hand, reaching 180° at 1.8 Hz (about 50° in healthy subjects). ME's hand lag is caused by the lack of any anticipatory reaction in hand movers. In contrast to healthy subjects, which activate the ECR earlier than the TA when the frequency increases, ME activated the ECR later than TA at all frequencies higher than 0.9 Hz.

Anti-phase movements (hand extension coupled to foot plantar flexion) were performed only upto 1 Hz in unloaded conditions. At 0.6 Hz, movements were in tight phase-opposition (3°), but at 1 Hz, the hand lag reached −34° because of a delayed ECR activation. After hand loading ME was unable to couple movements in anti-phase. In contrast, normal subjects maintain a tight anti-phase coupling up to 2.0 Hz, both with an unloaded or loaded hand. Similar deficits were observed by ME when performing in-phase and anti-phase coupling on the left side, as well as when he was blindfolded.

In normal subjects, an anticipated muscular activation of hand movers compensates for hand loading. Since this compensation must depend on monitoring the hand delay induced by loading, the absence in ME of such compensatory reaction suggests that callosal division had apparently compromised the mechanisms sustaining feedback compensation for differences in the biomechanical limb properties. They also confirm and reinforce the idea that elaboration of the afferent message, aiming at controlling the phase of the movement association, needs the co-operation of both cerebral hemispheres.     

Effects of right and left hemisphere damage on performance of the "Right Hemisphere Communication Battery"

A Hebrew adaptation of Gardner and Brownell's (1986) "Right Hemisphere Communication Battery" (HRHCB) was administered to 27 right brain-damaged (RBD) patients, 31 left brain-damaged (LBD) patients, and 21 age-matched normal controls. Both patient groups showed deficits relative to controls and overall there was no difference between the two patient groups. A factor analysis of patients' scores on the HRHCB yielded two interpretable factors, a verbal and a nonverbal one. These factors were not lateralized. Performance of patients on the HRHCB correlated significantly and positively with performance on most tests of basic language functions, measured with a Hebrew adaptation of the "Western Aphasia Battery" (HWAB) and with other cognitive functions measured with standardized neuropsychological tests. There were stronger correlations of HRHCB with subtests of the HWAB in LBD patients and with nonlanguage cognitive tests in RBD patients. In the LBD group, HRHCB subtests' scores correlated negatively with lesion extent in frontal and temporal perisylvian regions. Such localization was not observed in RBD patients. The results argue against selective right hemisphere (RH) involvement in the RHCB, alleged to measure pragmatic aspects of language use, and show, instead, bilateral involvement. The results also argue against a modular organization of these functions of language use, especially in the RH.     

Neuronal changes in normal human aging and Alzheimer's disease

This article discusses age-related changes in brain weight, total number of cortical neurons, cortical dendrites, spine, and synapse density. The conclusion is that the present outlook is less grim than it was 30 years ago. Age-related reduction appears to be specific to brain region and cortical layer rather than a general feature. In addition, we describe a different pattern of changes that occur in Alzheimer's disease patients. This review concludes that the association cortices in particular are affected in aging and Alzheimer's disease and that the primary visual and somatosensory cortices are relatively spared.     

From agape to organs: religious difference between Japan and America in judging the ethics of transplant

This essay argues that Japan's resistance to the practice of transplanting organs from persons deemed "brain dead" may not be the result, as some claim, of that society's religions being not yet sufficiently expressive of love and altruism. The violence to the body necessary for the excision of transplantable organs seems to have been made acceptable to American Christians at a unique historical "window of opportunity" for acceptance of that new form of medical technology. Traditional reserve about corpse mutilation had weakened and, especially as presented by the theologian Joseph Fletcher, organ donation was touted as both expressive of agape and a way of "updating" Christianity via the ethics of Utilitarianism. Many Japanese, largely Buddhist and Confucian in their orientation, view these changed valorizations as neither necessary nor patently more ethical than those of their own traditions.     

Traumatic Brain Injury as a Risk Factor for Alzheimer's Disease: A Review

Accumulating epidemiological evidence implicates traumatic brain injury as a pathogenic agent in the development of Alzheimer's disease (AD). Considering the increase in the prevalence of both traumatic brain injury and AD in recent times, the possibility that brain trauma may provoke the early development of AD has important implications for health service planning, preventative efforts, and medico-legal compensation settlements. This paper evaluates the plausibility of the proposed link between traumatic brain injury and AD, largely by way of exploring a theoretical perspective advanced by Satz (1993) and considering recent contributions from the epidemiological, neuropathological, and biochemical literature that are pertinent to this issue. The literature reviewed provides sufficient support and empirical vindication to give credence to the proposed association between these two neuropsychological entities at the statistical, theoretical, and biological level.     

Weak coherence,no theory of mind,or executive dysfunction? Solving the puzzle of pragmatic language disorders

Deficits in pragmatic language ability are common to a number of clinical populations, for example, right-hemisphere damage (RHD), Autism and traumatic brain injury (TBI). In these individuals the basic structural components of language may be intact, but the ability to use language to engage socially is impaired. Despite the nature of these difficulties being well documented, exactly what causes these difficulties is less clear. Furthermore, the current status of causal explanations for pragmatic difficulties across these populations is divergent and sometimes contradictory. This paper explores the empirical validity of three theories that attempt to explain pragmatic language impairment. It is recommended that a new, more convergent approach to investigating the causes of pragmatic language disability be adopted.