A simulation study of the degrees of freedom of movement in reaching and grasping

The question of independently controlled components in the act of reaching and grasping has attracted interest experimentally and theoretically. Data from 35 studies were recently found consistent with simulated kinematic finger and thumb trajectories optimised for minimum jerk. The present study closely reproduces those trajectories using a discrete-time model based on minimum acceleration. That model was further used to generate two-dimensional trajectories for finger and thumb to reach and grasp an elliptical object with varying position and/or orientation. Orthogonalisation of these four trajectories revealed one degree of freedom when direction of reach was constant and two degrees of freedom when direction of reach varied, irrespective of object distance and orientation. These simulations indicate that reach and grasp movements contain redundancy that is removable by formation of task-dependent synergies. As skilled movement can be planned and executed in a low dimension workspace, control of these independent components lessens central workload.     

Steep Cliff Arguments

In recent philosophical debates a number of arguments have been used which have so much in common that it is useful to study them as having a similar structure. Many arguments – Searle's Chinese Room, for example – make use of thought experiments in which we are told a story or given a narrative context such that we feel we are in comfortable surroundings. A new notion is then introduced which clashes with our ordinary habits and associations. As a result, we do not bother to investigate seriously the new notion any further. I call such an arrangement, which is perhaps a variation of the fallacy of presumption, a Steep Cliff argument. One remedy for the misdirection of a Steep Cliff argument is to tell a counterstory from the point of view of the rejected notion.     

Insincerity and disloyalty

Insincerity is the intentional conflict between a state of mind and a synchronic linguistic act. Three cases have to be distinguished: lying, as the opposition of belief and assertion (the act is untruthful); dishonesty, as the opposition of will and declaration of will (act empty); and simulation, as the opposition of emotion and exclamation (act ungenuine). One of the problems arising is: Are there insincere commands, and if not, why?

Disloyalty, on the other hand, is a diachronic inconsequence, the breach of a linguistic action (act unredeemed) which was binding for the future (such as, e.g. a promise). There is a cross-connection to dishonesty, which can be seen as the will to be disloyal.

     

记忆源检测的双加工机制研究

本研究借鉴Mitchell等人的图词归源和早晚归源任务,引发启发式和系统式加工,并引入知觉流畅性变量,试图在知觉层面上分离两种加工的底层工作模式。结果发现:(1)源检测具有相对脆弱性,成绩显著差于再认。(2)启发式加工和系统式加工在加工速度和底层工作模式上分离,启发式加工速度快,其工作模式似乎是对刺激的知觉流畅性进行阈下水平的解释与归因,而系统式加工速度慢,其工作模式似乎是对意义的分析与推理。     

智力和元认知技能在发现学习中的作用:任务复杂性的影响

采用自编的计算机模拟发现学习任务,以49名大学生为被试,探讨了在简单和复杂发现学习任务中,智力、元认知技能和学习成绩三者之间的关系。结果发现:在简单任务中,三者关系基本符合混合模型;进行过多的元认知活动,并不能提高学习效果。在复杂任务中,智力对学习成绩起主要预测作用。随着任务复杂性的增加,智力对学习的影响也随之变化,符合难度阈限理论的假设。任务复杂性不同时,智力、元认知技能和发现学习成绩之间的关系也不同,在一定程度上验证了难度阈限扩展理论。     

The accuracy of maternal self-reports: Agreement between reports on a computer simulation compared with observed behaviour in the supermarket

The validity of maternal self-reports about their parenting behaviour is evaluated with two studies. In both studies, the mothers were observed shopping in the supermarket with their 2-year-old children. One week later they responded to multiple choice questions on a computer that simulated the experience of shopping with their children. The exact agreement between the two types of data was then assessed. The results from the first study involving 28 mothers revealed some agreement, although it was generally low. In an effort to increase the level of agreement, the computer simulation was revised to allow multiple responses and to clarify some of the simulation vigenettes. A replication study resulted in a considerably higher level of agreement for 22 mothers. Implications of this method for researchers and practitioners are discussed.     

The automated cockpit: A comparison of attitudes towards human and automated pilots

Automation is being used extensively in aviation, particularly in the aircrafts themselves. The airline industry benefits from automation because it often increases efficiency and performance. To date, automation research has focused largely on operator trust and reliance, while largely ignoring the role of affect and trust in shaping the attitudes of the novice consumer. In two studies, we found that participants rated a human pilot more favorably than an auto-pilot. However, attitudes toward the automated pilot were more favorable in a high priced compared to a low priced ticket condition, indicating that participants used price to infer quality. In Study 2, inducing positive affect increased ratings of an automated pilot. Path analyses provided additional evidence that perceptions of automation are largely influenced by feelings.     

Mirror neurons and embodied simulation in the development of archetypes and self-agency

Abstract :  In this paper I explore the role of mirror neurons and motor intentionality in the development of self-agency. I suggest that this will also give us a firmer basis for an emergent view of archetypes, as key components in the development trajectory of self-agency, from its foundation in bodily action to its mature expression in mentalization and a conscious awareness of intentionality. I offer some ideas about the implications of these issues of self-agency for our clinical work with patients whose developmental trajectory of self-agency has been partially inhibited, so that their communications have a coercive effect. I discuss the possibility that this kind of clinical phenomenon may relate to Gallese and Lakoff's hypothesis that abstract thought and imagination are forms of simulated action, and that the same sensory-motor circuits that control action also control imagination, concept formation and understanding, but with a crucial development, that of an inhibition of the connections between secondary pre-motor cortical areas and the primary motor cortex. I shall speculate that in the earlier developmental stages of self-agency, the separation of secondary from primary motor areas is not complete, so that imagination and thought are not entirely independent of physical action.     

Simulation à la Goldman: pretend and collapse

Theories of mind draw on processes that represent mental states and their computational connections; simulation, in addition, draws on processes that replicate (Heal 1986) a sequence of mental states. Moreover, mental simulation can be triggered by input from imagination instead of real perceptions. To avoid confusion between mental states concerning reality and those created in simulation, imagined contents must be quarantined. Goldman bypasses this problem by giving pretend states a special role to play in simulation (Goldman 2006). We argue that this path leads to the resurgence of the threat of collapse (Davies 1994), diluting the principled distinction between simulation and theory use. Exploration of a related method of real-mental states operating in a pretend mode leads to a factually untenable model. Our main goal here is to raise this problem as a challenge for Goldman’s reconfigured simulation theory. Only at the end we will briefly sketch a possible alternative way of quarantine that preserves the replicative element of simulation and avoids collapse. Figure 1 provides a guide to our argument. Fig. 1 Structure of argument

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