Temporal perception in joint action: This is MY action

Here we investigated the temporal perception of self- and other-generated actions during sequential joint actions. Participants judged the perceived time of two events, the first triggered by the participant and the second by another agent, during a cooperative or competitive interaction, or by an unspecified mechanical cause. Results showed that participants perceived self-generated events as shifted earlier in time (anticipation temporal judgment bias) and non-self-generated events as shifted later in time (repulsion temporal judgment bias). This latter effect was observed independently from the kind of cause (i.e., agentive or mechanical) or interaction (i.e., cooperative or competitive). We suggest that this might represent a mental process which allows discriminating events that cannot plausibly be linked to one’s own action. When an event immediately follows a self-generated one, temporal judgment biases operate as self-serving biases in order to separate self-generated events from events of another physical causality.     

Time in action contexts: learning when an action effect occurs

Action effects do not occur randomly in time but follow our actions at specific delays. The ideomotor principle (IMP) is widely used to explain how the relation between actions and contingently following effects is acquired and numerous studies demonstrate robust action-effect learning. Yet, little is known about the acquisition of temporal delays of action effects. Here, we demonstrate that participants learn that action effects occur at specific delays. Participants responded slower to action effects that occurred earlier than usual. In addition, participants often prematurely responded before the effect when it occurred later than expected. Thus, in contrast to biases of time perception in action contexts (e.g., Haggard, Trends Cogn Sci 9:290–295, 2005; Stetson et al., Neuron 51:651–659, 2006), participants learn and exploit temporal regularities between actions and effects for behavioral control.     

Self-recognition: body and action

How do I know it was me who moved? A recent experimental study illustrates the contribution of one's body schema and awareness of one's own actions to self-recognition. The results provide evidence that bodily cues and action cues are important in self-recognition, and they demonstrate that action cues overrule bodily cues.     

putting action back into action planning: experiences of career clients

This study used the critical incident technique to investigate what helped and hindered unemployed and career‐changing people in implementing the action plans they developed while participating in career or employment counseling. Information from interviews with 23 women and 16 men generated 9 categories of helping incidents and 9 categories of hindering incidents. These categories increase understanding of the nature of action planning and reveal implications for preparing clients to engage in action planning activities.     

Perception in action: multiple roles of sensory information in action control

Perceptual processes play a central role in the planning and control of human voluntary action. Indeed, planning an action is a sensorimotor process operating on sensorimotor units, a process that is based on anticipations of perceptual action effects. I discuss how the underlying sensorimotor units emerge, and how they can be employed to tailor action plans to the goals at hand. I also discuss how even a single action can induce sensorimotor binding, how intentionally implemented short-term associations between stimuli and responses become autonomous, how feature overlap between stimulus events and actions makes them compatible, and why action plans are necessarily incomplete.

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.     

The cognitive representation of action: Automatic integration of perceived action effects

Actions have been assumed to be cognitively represented by codes of relevant action features. Six experiments investigated whether irrelevant action features — conditioned response-contingent auditory events — are also coded and integrated into action codes. Subjects responded to visual stimuli by pressing a left- versus right-hand button or by touching a single key once versus twice. Responses produced certain action effects: tones on the left versus the right or tones of low versus high pitch. After subjects had some practice, an inducing stimulus was presented together with the reaction stimulus; this inducing stimulus shared features with the action effect of the correct or incorrect response. If action effects were integrated into action codes, inducing stimuli should activate or prime the associated response. Indeed, substantial effects of correspondence or compatibility between inducing stimuli and irrelevant action effects were found in a variety of tasks. Results are interpreted as evidence for an automatic integration of information about action effects and taken as support of an action-concept model of action-effect integration and stimulus-response compatibility.     

ACT-PRO action protocol analyzer: A tool for analyzing discrete action protocols

This article presents a top-down approach for analyzing sequential events in behavioral data. Analysis of behavioral sequential data often entails identifying patterns specified by the researchers. Algorithms were developed and applied to analyze a kind of behavioral data, calleddiscrete action protocol data. Discrete action protocols consist of discrete user actions, such as mouse clicks and keypresses. Unfortunately, the process of analyzing the huge volume of actions (typically, > 10⁵) is very labor intensive. To facilitate this process, we developed an action protocol analyzer (ACT-PRO) that provides two levels of pattern matching. Level one uses formal grammars to identify sequential patterns. Level two matches these patterns to a hierarchical structure. ACT-PRO can be used to determine how well data fit the patterns specified by an experimenter. Complementarily, it can be used to focus an experimenter’s attention on data that do not fit the prespecified patterns.     

Grasping possibilities for action: influence of object function and action capabilities

The purpose of this study was to investigate the influence of object function and the observer's action capabilities on grasp facilitation. We used a stimulus-response compatibility (SRC) protocol in which participants were asked to reach and grasp a drinking glass using one of two grasps - the thumb-up or the thumb-down grasp. The reaction time (RT) was used as the index of grasp facilitation. In Experiment 1, we found evidence for the facilitation of "functionally relevant" grasps - where the type of grasp facilitated depended on the location of opening but not the shape of the object. However, this effect was found only when attention was directed toward the location of the opening. In Experiments 2 and 3, we found that this facilitation was also affected by whether participants had the ability to functionally interact with the object. These results show that S-R compatibilities are influenced both by the object's function and the actor's action capabilities, and are interpreted in Gibson's (1979) framework of affordances.     

Pulling out the intentional structure of action: the relation between action processing and action production in infancy

Adults and children readily construct action representations organized with respect to an ultimate goal. These representations allow one to predict the consequences of action, interpret and describe actions, and categorize action sequences. In this paper, we explore the ontogeny of hierarchically organized action representations, and its relation to infants' ability to produce similar sequences. To do so, we examine infants' perception and performance of a means-end sequence: pulling a cloth to retrieve a toy. Using a visual habituation paradigm, we demonstrate that 12-month-old infants understand that the initial step of the cloth-pulling sequence is directed toward the ultimate goal of attaining the toy, and use their knowledge of the causal constraints of the sequence to make this goal attribution. Ten-month-olds, however, appear transitional with respect to this understanding: their ability to identify the goal of the cloth-pulling sequence is related to their own ability to planfully solve a similar sequence. These findings are consistent with a burgeoning body of literature suggesting an intimate link between action production and perception, and suggest that this link is in place by at least 10 months of age.     

The influence of action observation on action execution: Dissociating the contribution of action on perception,perception on action,and resolving conflict

For more than 15 years, motor interference paradigms have been used to investigate the influence of action observation on action execution. Most research on so-called automatic imitation has focused on variables that play a modulating role or investigated potential confounding factors. Interestingly, furthermore, a number of functional magnetic resonance imaging (fMRI) studies have tried to shed light on the functional mechanisms and neural correlates involved in imitation inhibition. However, these fMRI studies, presumably due to poor temporal resolution, have primarily focused on high-level processes and have neglected the potential role of low-level motor and perceptual processes. In the current EEG study, we therefore aimed to disentangle the influence of low-level perceptual and motoric mechanisms from high-level cognitive mechanisms. We focused on potential congruency differences in the visual N190 ? a component related to the processing of biological motion, the Readiness Potential ? a component related to motor preparation, and the high-level P3 component. Interestingly, we detected congruency effects in each of these components, suggesting that the interference effect in an automatic imitation paradigm is not only related to high-level processes such as self-other distinction but also to more low-level influences of perception on action and action on perception. Moreover, we documented relationships of the neural effects with (autistic) behavior.     

Cyber terror: Missing in action

This article discusses the limited utility of the concepts of “cyber terrorism” or “electronic Pearl Harbor.” It contrasts the absence of cyber terror incidents with the large number of terrorist attacks and computer security incidents in recent years. It suggests that this discrepancy is explained both by the low appeal of cyber weapons to terrorists and because critical infrastructures and nations are not vulnerable to computer attacks. The article calls for a more rigorous approach to data collection for cyber security incidents, and suggests cyber security should not be seen primarily as a national security issue. Before joining CSIS, he served in the U.S. Foreign Service and worked on security, intelligence, and technology issues. Lewis’s current research covers cyber security, spectrum management, authentication, and technology’s role in national security. He received his Ph.D. from the University of Chicago in 1984.     

Translating visual information into action predictions: Statistical learning in action and nonaction contexts

Humans are sensitive to the statistical regularities in action sequences carried out by others. In the present eyetracking study, we investigated whether this sensitivity can support the prediction of upcoming actions when observing unfamiliar action sequences. In two between-subjects conditions, we examined whether observers would be more sensitive to statistical regularities in sequences performed by a human agent versus self-propelled ‘ghost’ events. Secondly, we investigated whether regularities are learned better when they are associated with contingent effects. Both implicit and explicit measures of learning were compared between agent and ghost conditions. Implicit learning was measured via predictive eye movements to upcoming actions or events, and explicit learning was measured via both uninstructed reproduction of the action sequences and verbal reports of the regularities. The findings revealed that participants, regardless of condition, readily learned the regularities and made correct predictive eye movements to upcoming events during online observation. However, different patterns of explicit-learning outcomes emerged following observation: Participants were most likely to re-create the sequence regularities and to verbally report them when they had observed an actor create a contingent effect. These results suggest that the shift from implicit predictions to explicit knowledge of what has been learned is facilitated when observers perceive another agent’s actions and when these actions cause effects. These findings are discussed with respect to the potential role of the motor system in modulating how statistical regularities are learned and used to modify behavior.     

动作理解因境而异:动作加工中情境信息的自动整合

针对动作理解的机制,模拟论主张大脑自发模拟他人的动作,就相同的动作其理解也相同,而理论论则认为人们基于合理性原则对他人动作进行推理,相同的动作发生在不同的情境时会有不同的理解。但以往研究所采用动作材料的运动学特性和发生情境存在共变,其难以区分动作理解是支持模拟论还是理论论。通过两项实验,采用动画制作技术来产生有无约束情境下的追逐动作,以指示动作加工过程的脑电μ抑制为指标,对前述两种观点进行了检验。其中,在约束情境中存在障碍物,追逐者需改变运动方向以绕过障碍物,从后方逐渐趋近目标;而无约束情境中不存在障碍物,但追逐者依然保持与存在约束情景下相同的运动模式。结果发现,当追逐动作发生在存在约束的情境时,其基于合理性原则推测可获得清晰的动作目标,该条件下的μ抑制程度高于不存在约束情境的条件(实验1);而当仅追逐者运动,即趋近的目标不确定时,虽然有约束和无约束情境间的物理差异与实验1相同,但条件间μ抑制的差异消失(实验2);且上述μ抑制并非与注意相关的枕叶α活动的泛化。该结果提示,动作发生的情境信息影响人们对动作的理解,即基于推理过程理解动作,支持理论论观点。