Motor facilitation following action observation: a behavioural study in prehensile action

Previous research has shown that the observation of actions and the execution of actions activate common neural systems. More recently, we have presented data showing that action observation of prehension primes subsequent execution (Castiello, Lusher, Mari, Edwards, & Humphreys, 2002). In the current paper we examined action priming under conditions in which the size of the prime did not predict the size of the target (only 20% of trials were valid). We demonstrated reliable priming under these conditions, consistent with the effect occurring automatically. In addition, we show priming even when observers saw just the object rather than the object and a reaching action on the prime trial. We discuss the findings in relation to the role of mirror neurons and object affordances.     

Gender differences in STEM undergraduates' vocational interests: People–thing orientation and goal affordances

This study addressed why women have greater representation in some STEM (science, technology, engineering, and mathematics) fields compared to others by linking two theoretical approaches, people–thing orientation (PO, TO) and role congruity theory, which emphasizes occupation goal affordances associated with traditionally feminine and masculine roles. Vocational interest and goal affordance ratings (having a positive social impact, family, and occupation status) for occupations characterized as working with people or things were assessed in 1848 students (42% female; 81% white non-Hispanic) majoring in biology (gender balanced), non-biology STEM (male-dominated), and female-dominated health fields. Participant PO and TO interests were also collected. Results indicated that non-biology STEM majors showed lower PO and higher TO interests than biology and health majors. Non-biology STEM majors also endorsed PO and TO interests at similar levels, but the other two major groups indicated higher PO than TO. People Jobs were perceived to more likely afford goals related to family and positive social impact; whereas Thing Jobs were perceived to more likely afford status goals. Interest in People Jobs was similar for women in both STEM major groups. Female non-biology STEM majors were equally interested in People and Thing Jobs; whereas biology majors preferred People Jobs. PO, TO, and goal affordance ratings independently predicted interest in People and Thing Jobs, and gender accounted for very little additional variance. Taken together, the findings point to the importance of using both person–thing orientation and role congruity theory when explaining varied gender representations in different STEM fields.     

Geometries and Dynamics of a Rod Determine How It Is Used for Reaching

Displacing an object with a hand-held rod provided a simple paradigm for studying tool use. The authors asked how reaching was affected by manipulations of rod properties. Adults held a rod (length = .10 to 1.5 m), with its tip in the air; walked toward an object on a table; chose a place to stop; and displaced the object with the rod's tip. In 3 experiments (Ns = 9, 22, and 17 participants), the authors manipulated rod length, mass, and mass distribution to determine whether and how geometric and dynamic properties affected the chosen distance and the posture. Both the chosen stopping distance and the postures were well accommodated to rod characteristics. Postural adaptations took place only in the arm, which was organized as a synergy. Predictably, rod length explained most of the variance, but small and reliable differences in both distance and posture depended on mass and mass distribution. The chosen distance anticipated not only rod length but also the upcoming posture needed to control the rod.     

Further evidence that object-based correspondence effects are primarily modulated by object location not by grasping affordance

Tipper, Paul and Hayes found object-based correspondence effects for door-handle stimuli for shape judgments but not colour. They reasoned that a grasping affordance is activated when judging dimensions related to a grasping action (shape), but not for other dimensions (colour). Cho and Proctor, however, found the effect with respect to handle position when the bases of the door handles were centred (so handles were positioned left or right; the base-centred condition) but not when the handles were centred (the object-centred condition), suggesting that the effect is driven by object location, not grasping affordance. We conducted an independent replication of Cho and Proctor's design, but with behavioural and event-related potential measures. Participants made shape judgments in Experiment 1 and colour judgments in Experiment 2 on the same door-handle objects. Correspondence effects on response time and errors were obtained in both experiments for the base-centred condition but not the object-centred condition. Effects were absent in the P1 and N1 data, which are consistent with the hypothesis of little binding between visual processing of grasping component and action. These findings question the grasping-affordance view but support a spatial-coding view, suggesting that correspondence effects are modulated primarily by object location.     

行动语义、客体背景和判断任务对客体动作承载性的影响

客体动作承载性指人们知觉客体时同时激活的针对客体的行动。当Gibson最初提出动作承载性概念时, 他认为客体的这种属性是可以自动激活的。然而近年来越来越多的证据显示, 在知觉和行动的关系中, 行动语义知识和客体所处背景对客体动作承载性具有调节作用, 表现在人们可以根据这些自上而下的信息选择针对客体的适当的行动。此外, 不同的判断任务在引发客体动作承载性效应上具有特异性, 表现在若判断任务仅需知觉客体表层属性时, 不能激活对客体的动作, 进而不能产生客体动作承载性; 若判断任务需要对客体进行深层加工时, 才会激活对客体的动作。未来研究还需要进一步探究行动语义知识和客体所处背景影响客体动作承载性发生的原因和机制, 以及不同判断任务中出现结果特异性的原因。     

Conflict in object affordance revealed by grip force

Viewing objects can result in automatic, partial activation of motor plans associated with them—“object affordance”. Here, we recorded grip force simultaneously from both hands in an object affordance task to investigate the effects of conflict between coactivated responses. Participants classified pictures of objects by squeezing force transducers with their left or right hand. Responses were faster on trials where the object afforded an action with the same hand that was required to make the response (congruent trials) compared to the opposite hand (incongruent trials). In addition, conflict between coactivated responses was reduced if it was experienced on the preceding trial, just like Gratton adaptation effects reported in “conflict” tasks (e.g., Eriksen flanker). This finding suggests that object affordance demonstrates conflict effects similar to those shown in other stimulus–response mapping tasks and thus could be integrated into the wider conceptual framework on overlearnt stimulus–response associations. Corrected erroneous responses occurred more frequently when there was conflict between the afforded response and the response required by the task, providing direct evidence that viewing an object activates motor plans appropriate for interacting with that object. Recording continuous grip force, as here, provides a sensitive way to measure coactivated responses in affordance tasks.     

ANTISTRUCTURE AND THE ROOTS OF RELIGIOUS EXPERIENCE

The cognitive and evolutionary sciences of religion offer a standard model of religious representations, but no equivalent paradigm for investigating religiously interpreted altered states of consciousness (religious ASCs). Here, I describe a neo-Durkheimian framework for studying religious ASCs that centralizes social predictive cognition. Within a processual model of ritual, ritual behaviors toggle between reinforcing normative social structures and downplaying them. Specifically, antistructural ritual shifts cognitive focus away from conventional affordances, collective intentionality, and social prediction, and toward physical affordances and behavioral motivations that make few references to others’ intentional states. Using synchrony and dance as paradigmatic examples of antistructural ritual that stimulate religious ASCs, I assemble literature from anthropology, cognitive neuroscience, and philosophy of language to offer fruitful empirical predictions and opportunities for testing based on this framework. Among the empirical predictions is that antistructural ritual may provide for cultural change in religions when religions are construed as complex adaptive systems.     

The Space of Motivations

Abstract

The distinction between the space of reasons and the realm of law captures two familiar ways of making events intelligible, by reference to reasons or to natural laws, respectively. I describe a third way of making events intelligible, by explaining them in terms of an agent’s being motivated to do certain things. Explanations of this sort do not involve appealing to reasons for which the agent acts, nor to natural laws under which the event falls. To explain an event in this way is to place it in the space of motivations. I outline the relation between the space of motivations and the space of reasons, and suggest that the space of motivations may serve as a common ground between the positions defended by McDowell and Dreyfus in their recent debate.     

Does Conditional Affordance Imply Representational Non-Conceptual Content?

Jan Alm?ng believes that James J. Gibson’s notion of affordances offers a reason to reject John McDowell’s thesis that representational perceptual content is conceptual through and through. I argue that Alm?ng’s arguments for the claim that the perceptual content in which conditional affordances feature can be both representational and non-conceptual are questionable.     

语篇理解中动允性信息的提取

通过三个实验考察了读者在语篇理解中对动允性(affordance)信息的提取状况, 以及动允性在阅读理解中的意义。实验一的结果表明, 被试在阅读理解中, 会自发地提取语篇中的动允性信息, 并围绕着动允性信息组织其他信息; 在IEF中的解析过程中, 动允性信息对其他信息有组织作用。实验二的结果表明, 被试在阅读理解中能够直接提取动允性信息。实验三的结果表明, 被试在阅读理解中存在两条提取动允性信息的通路, 一条是直接提取动允性信息, 另一条是先提取属性信息再推导出动允性信息, 选择哪条通路取决于被试是否得到了属性信息。三个实验的结果表明, 阅读理解中的动允性与知觉过程中的动允性存在着相当大的相似性。