准备状态对反应抑制的影响

从事件因素和时间因素两个方面探讨了准备状态对反应抑制的影响。事件准备可降低反应模式的不确定性 ,而时间准备则与降低反应时间的不确定性有关。线索、反应概率以及刺激呈现时间等因素不仅导致反应时间出现变化 ,还可引起反应力、心跳间期以及LRP和CNV等脑电指标发生变化。传统的反应抑制研究以反应时为指标 ,不能揭示反应抑制的内部过程 ,而心理生理学方法能弥补这一缺陷。生理指标与行为指标的结合 ,以及生理指标之间的结合 ,可更有效地探讨准备状态对反应抑制的效应。     

言语产生的认知神经机制

从认知神经科学的角度阐述了言语产生中时间进程及其激活脑区的研究进展。首先简单介绍了言语产生中词汇通达的2种理论观点。在此基础上介绍了运用电生理技术指标LRP和N200,采用双重判断任务范式对言语产生的时间进程的研究。最后论述了有关语言产生的神经心理学研究和脑成像研究,重点阐述了言语产生中时间进程相对应的激活脑区,言语产生的脑区表现出左侧化趋势。     

反应控制中运动系统抑制效应的全局性：证据、机制和争论

在反应控制的研究中,长期以来的理论观点认为只有干扰当前目标的效应器会出现抑制效应。总结近年研究发现,在反应控制过程中,不仅干扰效应器出现了抑制效应,与任务无关的效应器和任务要求效应器均出现了抑制效应;与反应控制相关的抑制效应不仅仅局限于涉及反应冲突的任务,而是广泛存在于涉及反应执行的任务,即整个运动系统在多个情境下呈现抑制的全局性。双加工模型认为对不同效应器的抑制由不同脑区控制,聚光灯模型则认为不同效应器的抑制源于同一个系统,后者与计算神经科学领域的归一化模型一致。反应控制中抑制效应的全局性特征有助于从协同性和整体性的角度思考认知加工。同时,当前研究对抑制效应全局性出现的条件也存在一些争论。未来研究应区分不同效应器,结合计算模型阐明各效应器之间的协同作用机制、各效应器在运动皮层的计算机制,以及这些机制异常与心理精神疾病人群反应控制失调的关系。     

认知心理学"经典范式"的系统阐述--评梁宁建著《当代认知心理学》

如果从1967年U．Neisser出版《认知心理学》算起,以“信息加工”概念为核心或标志的所谓“认知心理学”或“信息加工心理学”,迄今已近40个年头了。这种信息加工心理学,由于以计算机为“隐喻”（认知心理学史上称“计算机隐喻”：心理之于大脑,犹如软件之于硬件）,以H．Simon和A．Newell的“物理符号系统假设”（“PSSH”）为基础理论,以“人脑-机器的功能同一”（俗称“人机类比”）为方法论,并以其对高级认知功能（思维、问题解决、推理、决策等）强劲的解释力,而一直在当代心理学中独领风骚,以至被称为认知心理学的“经典范式”。这里的“经典”至少意味着,这种范式是经得起时间的检验的。     

前置线索对动作准备不同阶段的影响

以动作准备的左右手线索和方向线索为对象,结合LRP(单侧化预备电位)潜伏期和CNV(伴随性负变化)振幅等脑电指标,探讨不同前置线索对动作准备各个阶段的影响。结果发现:(1)当两个线索相继呈现时,"方向线索 手线索"诱发的CNV振幅大于"手线索 方向线索",说明在前一情景下,方向线索呈现时,被试同时对左右两手的运动程序做准备;(2)在"手线索 方向线索"情景下,LRP的启动先于方向线索的呈现。上述结果与"动作准备的层次假设"相符合,说明动作参数的具体化过程遵循手、手指、方向、力等的顺序进行。此外,本研究没有发现支持"方向线索的准备可易化LRP启动后的运动阶段"的证据。     

面孔加工的认知神经科学研究：回顾与展望

面孔加工的认知神经科学研究中的核心问题是,是否存在功能和神经机制上独立的面孔加工模块以及面孔加工系统的组织形式。使用电生理、脑成像以及对脑损伤病人进行神经心理学检查等手段,研究者已经找到选择性地对面孔反应的脑区,即梭状回面孔区（FFA）。文章从面孔加工系统的特异性与多成分性以及面孔识别模型等方面,系统回顾了该领域的主要研究成果。文章最后还简单展望了今后的研究方向。     

教师关于儿童入学准备的观念

入学准备是指学龄前儿童为了能够从即将开始的正规学校教育中受益所需要具备的各种关键特征或基础条件.入学准备研究对于存在潜在发展风险之儿童的早期识别和及时干预具有重要价值.为了了解中国儿童入学准备应包含哪些方面,对76名幼儿园大班教师和65名小学一年级教师进行了半结构式访谈,结果发现:(1)中国儿童的入学准备可以归纳为26个项目;(2)“社会性与情绪发展”和“学习方式”领域的入学准备和适应问题被教师提及的次数较多,“认知发展与一般知识”、“言语发展”领域被提及较少,“身体健康和运动发展”领域被提及最少;(3)幼儿园教师和小学一年级教师对于入学准备所涉内容的看法比较接近;(4)小学一年级教师认为自理能力、学习技能和同伴交往等方面是当前幼儿园教育的薄弱环节.最后,结合访谈结果及NEGP模型对中国儿童入学准备研究的未来方向提出了建议.     

双语脑的研究:不同的语言是否有不同的皮层机制?

随着认知神经科学技术的发展,研究者对“不同语言是否有不同的大脑皮层机制?”这个问题的研究也进一步深入。一系列的神经心理学和脑成像研究表明,语言获得的时问、流利程度、获得方式等都可能成为影响语言的皮层机制的因素。     

认知脑电技术在职务犯罪侦查中的应用探析

针对职务犯罪数量居高不下,涉案人高智商不断增高、作案方式多样且隐蔽等日益严峻的犯罪形势,脑电认知测谎技术的运用可以有效提高嫌疑人检出率,服务于职务犯罪的侦查应用之中。通过设计特定的刺激呈现方式与被测人员反应方式,以及对测试后期数据的分析,测试人员可以有效的排除无辜、认定嫌犯,达到提高办案效率的目的。相信在不久的将来,认知脑电测试法将成为辅助职务犯罪案件侦查的重要手段。     

手的拦截运动的速度伴随效应及影响因素

对手的拦截运动的理论假设、速度伴随效应及其影响因素进行了总结和分析。指出:(1)“速度伴随效应”的机制可能在于补偿反应延迟、维持必需的注视时间、对即时运动信息的利用或时间-准确性权衡;(2)手的拦截运动指标受目标运动方向、先前任务、练习、目标大小、运动表征和策略以及双眼线索等因素的影响;(3)对拦截运动的进一步研究可在统一理论解释的基础上进行,克服研究方法和范围的局限。     

Programming of expected and unexpected movements: effects on the onset of the lateralized readiness potential

When participants utilize prime information to prepare some or all aspects of the forthcoming movement, reaction time (RT) costs are obtained when the imperative response signal demands an unexpected rather than an expected movement. Longer RT in trials for which primes are invalid rather than valid, i.e., the response validity effect, are taken to reflect prolonged motoric processing time. The present study was designed to test this assumption by using the lateralized readiness potential (LRP) in order to reveal influences of response validity at motoric processes, pre-motoric processes, or both. In two response priming experiments LRP onset latency was examined when valid and invalid advance information about direction (Experiment 1) or about direction and hand (Experiment 2) was provided. RT revealed large response validity effects in both experiments. Analysis of LRP onsets provided strong evidence against the common assumption of a motoric locus of the RT increase in invalid trials. Rather, the present results suggest a pre-motoric locus of the response validity effect within information processing.     

Influences of presentation mode and time pressure on the utilisation of advance information in response preparation.

An important approach to the investigation of movement selection and preparation is the precuing paradigm where preliminary information about a multidimensional response leads to reaction time benefits which are positively related to the amount of precue information. This so-called precuing effect is commonly attributed to data-limited preparatory motoric processes performed in advance of the response signal. By means of recording the lateralised readiness potential (LRP), the present experiments investigated whether the precuing effect could be explained also by variables that affect strategic utilisation of stimulus-conveyed information. Experiment 1 presented fully and partially informative precues either in mixed or blocked mode. Experiment 2 exerted various degrees of time pressure to the different precue conditions. In both experiments, the precuing effect on reaction times and the LRP was fully preserved, refuting the notion that the sensitivity of the LRP to the amount of preliminary information merely reflects differential precue utilisation. As a major finding, time pressure increased the LRP amplitude during response preparation which is consistent with the view that response strategies generally influence movement preparation on a motoric level.     

An investigation of the neural correlates of attention and effector switching using ERPs

Event-related brain potentials (ERPs) were used to examine the neural correlates of attention and effector switching when one or both types of switches were performed on a given trial. The response time data revealed that switch costs tended to increase from attention switches to effector switches to attention1effector switches. For right-hand responses, attention switching was associated with a parietal slow wave and effector switching was associated with a central readiness potential. For left-hand responses, attention switching was associated with a parietal slow wave, and effector switching was associated with a parietal slow wave and a readiness potential. These data suggest that the independence of the neural systems supporting attention and effector switching may be limited to instances where the dominant hemisphere controls the response.     

The lateralized readiness potential as an on-line measure of central response activation processes

The lateralized readiness potential (LRP) is an electrophysiological indicator of the central activation of motor responses. Procedures for deriving the LRP on the basis of event-related brain potential (ERP) waveforms obtained over the left and right motor cortices are described, and some findings are summarized that show that the LRP is likely to reflect activation processes within the motor cortex. Two experiments investigating spatial S-R compatibility effects are reported that demonstrate that, because of systematic overlaps of motor and nonmotor asymmetries, LRP waveforms derived by the double subtraction method cannot always be interpreted unequivocally in terms of response activation. Such confounds can be detected when LRP waveforms are compared with difference waveforms obtained by the double subtraction method from ERPs elicited at other lateral scalp sites.     

The temporal selectivity of additive factor effects on the reaction process revealed in ERP component latencies

An experiment was conducted to relate individual components of the event-related brain potential to specific stages of information processing in a two-choice reaction time (RT) task in a group of undergraduate students. Specifically, the latency of the P300 component and the lateralized readiness potential (LRP) were studied as a function of variations in stimulus degradation and response complexity. It was hypothesized that degrading the stimulus would delay the P300 and LRP to the same extent as RT, and that increasing response complexity would affect RT but not P300 latency. The extant literature did not permit any hypothesis regarding the effect of response complexity on LRP latency. The two task variables were found to have additive effects on RT. As predicted, variations in stimulus degradation influenced the latencies of both components, whereas alterations in response complexity had no effect on P300 latency. A significant new finding was that the onset latency of the LRP remained unchanged across levels of response complexity. The overall pattern of results supports the notion of temporal selectivity of stage manipulations that is derived from discrete stage models of human information processing. Furthermore, these results refine the functional interpretation of the LRP by indicating that within the conceptual framework of a stage model the processes this component indexes succeed the start of response choice but precede the start of motor programming.     

Inhibition of return from stimulus to response

In a standard inhibition-of-return (IOR) paradigm using a manual key-press response, we examined the effect of IOR both on the amplitude of early sensory event-related brain potential (ERP) components and on the motor-related lateralized readiness potential (LRP). IOR was associated with a delay of premotor processes (target-locked LRP latency) and reduced sensory ERP activity. No effect of IOR was found on motor processes (response-locked LRP latency). Thus, IOR must arise at least in part from changes in perceptual processes, and, at least when measured with manual key presses, IOR does not arise from inhibition of motor processes. These results are consistent with the results of attention-orienting studies and provide support for an inhibition-of-attention explanation for IOR.     

Multiple bottlenecks in information processing? An electrophysiological examination

When two stimuli are to be processed in rapid succession, reaction time (RT) to the second stimulus is delayed. The slowing of RT has been attributed to a single processing bottleneck at response selection (RS) or to a central bottleneck following the initiation of the first response. The hypothesis of a response initiation bottleneck is mainly based on reports of underadditive interactions between stimulus onset asynchrony (SOA) and the number of stimulus—response alternatives (simple vs. two-choice response). The present study tested the hypothesis of a response initiation bottleneck by recording the lateralized readiness potential (LRP), a brain wave, emerging during or immediately following RS. The LRP findings were consistent with a central bottleneck but did not support the late bottleneck hypothesis. Instead, the LRP provided direct evidence that the underadditive interaction of number of alternatives and SOA is due to an increase of response anticipations in the simple response condition.     

Being prepared on time: on the importance of the previous foreperiod to current preparation, as reflected in speed, force and preparation-related brain potentials

How do participants adapt to temporal variation of preparatory foreperiods? For reaction times, specific sequential effects have been observed. Responses become slower when the foreperiod is shorter on the current than on the previous trial. If this effect is due to changes in motor activation, it should also be visible in force of responses and in EEG measures of motor preparation, the contingent negative variation (CNV) and the lateralized readiness potential (LRP). These hypotheses were tested in a two-choice reaction task, with targets occurring 500, 1500, or 2500 ms after an acoustic warning signal. The reaction time results showed the expected pattern and were accompanied by similar effects on a fronto-central CNV and the LRP. In contrast, the increase of response force with brief current foreperiods did not depend on previous foreperiods. Thus, EEG measures confirm that sequential effects on RT are at least partially due to changes in motor activation originating from previous trials. Effects found on response force may be related to general response readiness rather than activation of motor-hand areas, which may explain the absence of a sequential effect on force in the current experiment.     

Localizing practice effects in dual-task performance

Practice effects on dual-task processing are of interest in current research because they may reveal the scope and limits of parallel task processing. Here we used onsets of the lateralized readiness potential (LRP), a time marker for the termination of response selection, to assess processing changes after five consecutive dual-task sessions with three stimulus onset asynchronies (SOAs) and priority on Task 1. Practice reduced reaction times in both tasks and the interference between tasks. As indicated by the LRP, the reduction of dual-task costs can be explained most parsimoniously by a shortening of the temporal demands of central bottleneck stages, without assuming parallel processing. However, the LRP also revealed a hitherto unreported early activation over the parietal scalp after practice in the short SOA condition, possibly indicating the isolation of stimulus–response translation from other central processing stages. In addition, further evidence was obtained from the LRP for a late motoric bottleneck, which is robust against practice.