Learning in the brain–computer interface: insights about degrees of freedom and degeneracy from a landscape model of motor learning

In this paper, we examine the role of degrees of freedom and their degeneracy in learning in the brain–computer interface paradigm. Though the traditional notion of degrees of freedom in motor learning gave emphasis to muscle and joint activity, the broader concept of dimensions of behavior is relevant to brain–computer interface learning where there is no muscle activity. The role of degeneracy in the dimensions of brain activity is proposed to enhance learning through robustness to stability loss and adaptability in the search for new stable states. Principles for the application of augmented information for learning to coordinate and control the degenerate degrees of freedom in the brain–computer interface are outlined.     

De‐escalation after repeated negative feedback: emergent expectations of failure

Research on willingness to make marginal investments (e.g., the escalation and sunk cost literatures) has often focused on project completion decisions, such as the “radar‐blank plane.” This paper discusses a fundamentally different type of marginal investment decision, that of couples deciding whether to continue infertility treatment in the face of repeated failures. Two experiments based on this context show that when people face multiple independent chances to achieve a valued goal but are unsure about chances of success, premature quitting or “de‐escalation” is the norm. Repeated negative feedback appears to induce individuals to see each successive failure as more and more diagnostic. As a result, even a short series of failed attempts evokes beliefs that future attempts will also fail. These emergent expectations of failure, generated by causal attribution processes, associative learning, and/or discounting of ambiguous information, appear very compelling and induce people to forgo profitable marginal investments. Copyright © 2004 John Wiley & Sons, Ltd.     

具体情绪及非依随反馈方式对自我妨碍的影响

该研究采用实验法考察了具体情绪以及非依随反馈方式对自我妨碍的影响。被试为104名大学生。结果表明：1）愉快组被试做出的决策型自我妨碍行为较少;恐惧组被试做出的回避型自我妨碍较多。2）两种非依随反馈方式对自我妨碍的影响没有显著差异。3）无论是决策型自我妨碍还是回避型自我妨碍,男生均高于女生。     

Exploring the informational sources of metaperception: the case of Change Blindness Blindness

Perceivers generally show a poor ability to detect changes, a condition referred to as “Change Blindness” (CB). They are, in addition, “blind to their own blindness”. A common explanation of this “Change Blindness Blindness” (CBB) is that it derives from an inadequate, “photographical” folk-theory about perception. This explanation, however, does not account for intra-individual variations of CBB across trials. Our study aims to explore an alternative theory, according to which participants base their self-evaluations on two activity-dependent cues, namely search time and perceived success in prior trials. These cues were found to influence self-evaluation in two orthogonal ways: success-feedback influenced self-evaluation in a global, contextual way, presumably by recalibrating the norm of adequacy for the task. Search time influenced it in a local way, predicting the success of a given trial from its duration.     

任务难度和反馈学习对儿童类比推理能力的影响

该研究采用情景类比任务,通过两个实验对180名小学生进行纸笔测验,探讨了任务难度对儿童类比推理能力的影响.结果发现:进行反馈学习以降低任务难度时,7～8岁儿童能完成更高年龄段儿童才能完成的任务;但增加任务难度,11岁以上儿童也表现出类比推理能力的弱化.结果提示,儿童是否能在类比推理任务中表现出相应的能力可能取决于任务难度,反馈学习可促进一定年龄段内儿童的类比推理能力发展.本结果为有机融合皮亚杰和Goswami等人的观点提供了有效的实验依据.     

成败反馈对大学生核心自我评价的影响：任务重要性、外向性的调节作用

该研究以247名大学生为被试,采用2（反馈类型：成功、失败）×2（任务重要性：重要任务、不重要任务）×2（外向性：内向、外向）组间设计探讨成败反馈对大学生核心自我评价的影响,以及任务重要性和外向性在其中的调节作用。结果表明：（1）反馈类型、任务重要性和外向性对核心自我评价变化的主效应及三者的交互作用效应均显著。（2）成败反馈与任务重要性对核心自我评价变化存在显著的交互作用;简单效应分析表明,在失败反馈条件下,执行重要任务被试核心自我评价的下降幅度显著大于执行不重要任务被试核心自我评价的下降幅度。（3）成败反馈与外向性对核心自我评价变化存在显著的交互作用;简单效应分析显示,在失败反馈条件下,外向被试核心自我评价的下降幅度显著小于内向被试。（4）在失败反馈条件下,任务重要性和外向性对核心自我评价的变化存在交互作用。     

反馈延迟与掩蔽类型对知觉类别学习的影响

通过两个实验探讨反馈延迟与掩蔽类型对知觉类别学习的影响。实验1光栅掩蔽条件下,采用2（类别结构：基于规则vs.信息整合）×2（延迟反馈：500vs.3000ms）被试间实验设计,实验2采用同样的实验设计,保持延迟反馈时间不变,但改掩蔽类型为黑屏掩蔽。结果发现：（1）光栅掩蔽条件下,反馈延迟削弱信息整合类别结构的成绩,不影响基于规则类别学习,内隐外显类别结构之间存在分离效应。（2）黑屏掩蔽条件下,信息整合与基于规则类别结构的成绩均不受到延迟反馈的影响,分离效应消失。实验说明“无关因素”掩蔽影响知觉类别学习,知觉噪音与标准噪音在反馈延迟影响知觉类别学习中起到重要作用,COVIS模型理论关于延迟反馈时间影响知觉类别学习的解释具有局限性。     

Using real-time visual feedback to improve posture at computer workstations

The purpose of the current study was to examine the effects of a multicomponent intervention that included discrimination training, real-time visual feedback, and self-monitoring on postural behavior at a computer workstation in a simulated office environment. Using a nonconcurrent multiple baseline design across 8 participants, the study assessed the effects of the intervention across three postural variables. Following an information phase, the intervention started for the lowest stable postural variable. The intervention led to substantial improvements in safety behavior for most targeted postural variables. A reversal to the information phase for 2 participants did not lead to decreases in safety. Postures self-monitored with high accuracy improved to a greater degree than postures self-monitored with low accuracy.     

Evaluation of an efficient method for training staff to implement stimulus preference assessments

We used a brief training procedure that incorporated feedback and role-play practice to train staff members to conduct stimulus preference assessments, and we used group-comparison methods to evaluate the effects of training. Staff members were trained to implement the multiple-stimulus-without-replacement assessment in a single session and the paired-stimulus method in another single session. In all 16 cases (2 assessments for 8 trainees), correct responding increased to over 80% accuracy; in 14 of those 16 cases, it increased to over 90% accuracy. Thus, training produced mastery-level performance in a single training session in almost all cases.     

Effects of Attention on the Strength of Lexical Influences on Speech Perception: Behavioral Experiments and Computational Mechanisms

The effects of lexical context on phonological processing are pervasive and there have been indications that such effects may be modulated by attention. However, attentional modulation in speech processing is neither well documented nor well understood. Experiment 1 demonstrated attentional modulation of lexical facilitation of speech sound recognition when task and critical stimuli were identical across attention conditions. We propose modulation of lexical activation as a neurophysiologically plausible computational mechanism that can account for this type of modulation. Contrary to the claims of critics, this mechanism can account for attentional modulation without violating the principle of interactive processing. Simulations of the interactive TRACE model extended to include two different ways of modulating lexical activation showed that each can account for attentional modulation of lexical feedback effects. Experiment 2 tested conflicting predictions from the two implementations and provided evidence that is consistent with bias input as the mechanism of attentional control of lexical activation.