Taking a closer look: time sampling and measurement error

A person manufactured his in-seat behavior for 15, 30-min sessions so that there were three blocks of five sessions where the behavior occurred 20%, 50%, and 80% of the time. Whole interval, partial interval, and momentary time-sample measures of the behavior were taken and compared to the continuous measure of the behavior i.e., per cent of time the behavior occurred. For interval time sampling, the difference between the continuous and sample measures i.e., measurement error, was: (1) extensive, (2) unidirectional, (3) a function of the time per response, and (4) inconsistent across changes in the continuous measure. A procedural analysis demonstrated that the frequency and duration of behavior are confounded in interval time sampling. Momentary time sampling was found to be superior to interval time sampling in estimating the duration a behavior occurs.     

An evaluation of time-sample measures of behavior

Continuous and time-sample measures of the in-seat behavior of a secretary were obtained. Measurement error, i.e., the extent to which the sample measures deviated from the continuous measure, was a function of the frequency of the sample measurements and the criterion used to score an example of the behavior. If the behavior had to be exhibited throughout the observational interval (whole-interval time sampling), there was a consistent underestimate of the continuous measure. If the behavior had to be exhibited only briefly within the observational interval (partial-interval time sampling), there was a consistent overestimate of the continuous measure. And, if the behavior had to be exhibited at the end of the observational interval (momentary time sampling), overestimations and underestimations of the continuous measure occurred about equally often. As expected, the more frequently the sample measures were made the closer was the agreement between the sample and continuous measures. Two conclusions concerning measurement error in interval time sampling were made. The first was that the error will be a function of the mean time per response. The second is that this error will not be consistent across experimental conditions.     

探索道路上的十年——“现代小学数学”教学实验

本文是对十年来的“现代小学数学”教学实验的初步总结。实验结果表明:1.把作为主体认识对象的客体(小学数学知识)的建构与对主体对客体认识的发展规律的研究有机发结合起来,这一研究小学生数学思维发展的总体设计是可行的、有效的;2.有意识地揭示小学数学知识内在的辩征关系以萌发小学生的辩证思维,不仅有必要,而且有可能;3.心理学研研人员与教学研究人员和广大教师相结合,是进行教学实验的一条比较理想的途径。     

主动控制感在大脑表征中的时空标记

主动控制感是主动动作过程中产生的控制自身动作, 进而控制外部环境的主观体验。构成动作主动控制感的核心要素是主观意图与结果反馈。本研究试图通过操控这两个核心要素的不同属性, 借助脑磁图等技术, 探寻主动控制感在大脑额-顶为主的脑网络中前-后馈的作用方式及时空特异性标记, 并建构新的认知神经理论模型。这将有利于理解人类动作的产生及后效、为相关精神类疾病的临床诊断提供更加客观的参照标准。     

Effects of antagonistic and synergistic muscles’ co-activation on mechanics of activated spastic semitendinosus in children with cerebral palsy

ObjectivesMost activities involve co-activation of several muscles and epimuscular myofascial force transmission (EMFT) can affect their mechanics. This can be relevant for spastic muscles of cerebral palsy (CP) patients. Isometric spastic semitendinosus (ST) forces vs. knee angle (KA-F_ST) data were collected intra-operatively to test the following hypotheses: (i) Inter-antagonistic EMFT elevates F_ST, (ii) changes the shape of KA-F_ST characteristics, (iii) reduces the muscle’s joint range of force exertion (Range-F_ST) and (iv) combined inter-antagonistic and synergistic EMFT further changes those effects.Methods11 limbs of 6 patients with CP (mean (SD) = 7.7 (4.7) years; GMFCS levels = II–IV) were tested in 3 conditions from 120° to full extension: ST activated (I) exclusively, (II) simultaneously with an antagonist, and (III) with added activation of synergists.ResultsCondition II increased F_ST (e.g., peak force = 87.6 N (30.5 N)) significantly (by 33.6%), but condition III caused no further change. No condition changed the muscle’s wide Range-F_ST (100.7° (15.9°)) significantly. Therefore, only the first hypothesis was confirmed.ConclusionsCo-activating its antagonist elevates forces of activated spastic ST substantially, but does not change its joint range of force exertion. Added activation of its synergists causes no further effects. Therefore, EMFT effects in CP can be relevant and need to be tested in other knee flexors.     

Relationships among pain intensity,pain-related distress,and psychological distress in pre-surgical total knee arthroplasty patients: a secondary analysis

The current study aimed to examine the relationships between movement and resting pain intensity, pain-related distress, and psychological distress in participants scheduled for total knee arthroplasty (TKA). This study examined the impact of anxiety, depression, and pain catastrophizing on the relationship between pain intensity and pain-related distress. Data analyzed for the current study (N = 346) were collected at baseline as part of a larger Randomized Controlled Trial investigating the efficacy of TENS for TKA (TANK Study). Participants provided demographic information, pain intensity and pain-related distress, and completed validated measures of depression, anxiety, and pain catastrophizing. Only 58% of the sample reported resting pain >0 while 92% of the sample reported movement pain >0. Both movement and resting pain intensity correlated significantly with distress (r_s = .86, p < .01 and .79, p < .01, respectively). About three quarters to two thirds of the sample (78% for resting pain and 65% for movement pain) reported different pain intensity and pain-related distress. Both pain intensity and pain-related distress demonstrated significant relationships with anxiety, depression, and catastrophizing. Of participants reporting pain, those reporting higher anxiety reported higher levels of distress compared to pain intensity. These findings suggest that anxious patients may be particularly distressed by movement pain preceding TKA. Future research is needed to investigate the utility of brief psychological interventions for pre-surgical TKA patients.     

汉字整体和笔画频率对笔画认知的影响

为考察笔画在汉字认知中的作用,探讨了汉字整体和笔画频率对笔画认知的影响。结果表明：（1）和部件识别类似,笔画认知存在着显著的字劣效应：识别汉字中的笔画比识别单独呈现的笔画反应时明显地长,错误率也大幅度增加,显示了汉字整体对笔画认知的抑制性影响。（2）识别汉字中的笔画的反应时也受背景汉字笔画多少的影响。识别少笔画汉字中的笔画比识别多笔画汉字中的笔画容易。（3）笔画频率对笔画认知也有重要影响,频率高的笔画比频率低的笔画容易识别     

青年大学生自信的理论建构研究

通过文献分析与实证研究,构建了自信的理论维度,并据此编制了青年大学生自信的测量量表。对量表进行探索性因素分析和验证性因素分析后表明:大学生自信是一个多维度、多层次的心理系统,具有复杂的结构,包含4个层次和13个维度,该研究所构建的理论体系比较合理。量表具有较好的信度和效度,可以作为青年大学生自信研究的测量工具。     

The Influence of an Acute Bout of Whole Body Vibration on Human Postural Control Responses

The use of vibrating platforms has become increasingly available, and popular at sports and rehabilitation institutes. Given the discrepancies in the literature regarding whole body vibration (WBV) and human reflexive responses, the purpose of this study was to examine the acute effects of WBV on postural response latencies, as well as associated electromyography measures of the lower extremities during balance perturbations. Reflexive responses during backward and forward balance perturbations were examined before, after, and 10 min after a bout of WBV. The findings suggest that following an acute bout of whole body vibration, muscle activity of the lower extremities is decreased during a reflexive response to an unexpected perturbation, and may be associated with faster reaction time.     

Temporal compression in episodic memory for real-life events

Remembering an event typically takes less time than experiencing it, suggesting that episodic memory represents past experience in a temporally compressed way. Little is known, however, about how the continuous flow of real-life events is summarised in memory. Here we investigated the nature and determinants of temporal compression by directly comparing memory contents with the objective timing of events as measured by a wearable camera. We found that episodic memories consist of a succession of moments of prior experience that represent events with varying compression rates, such that the density of retrieved information is modulated by goal processing and perceptual changes. Furthermore, the results showed that temporal compression rates remain relatively stable over one week and increase after a one-month delay, particularly for goal-related events. These data shed new light on temporal compression in episodic memory and suggest that compression rates are adaptively modulated to maintain current goal-relevant information.