Intention and attention in ideomotor learning

Human actions may be carried out in response to exogenous stimuli (stimulus based) or they may be selected endogenously on the basis of the agent's intentions (intention based). We studied the functional differences between these two types of action during action–effect (ideomotor) learning. Participants underwent an acquisition phase, in which each key-press (left/right) triggered a specific tone (low pitch/high pitch) either in a stimulus-based or in an intention-based action mode. Consistent with previous findings, we demonstrate that auditory action effects gain the ability to prime their associated responses in a later test phase only if the actions were selected endogenously during acquisition phase. Furthermore, we show that this difference in ideomotor learning is not due to different attentional demands for stimulus-based and intention-based actions. Our results suggest that ideomotor learning depends on whether or not the action is selected in the intention-based action mode, whereas the amount of attention devoted to the action–effect is less important.     

Two modes of sensorimotor integration in intention-based and stimulus-based actions

Human actions may be driven endogenously (to produce desired environmental effects) or exogenously (to accommodate to environmental demands). There is a large body of evidence indicating that these two kinds of action are controlled by different neural substrates. However, only little is known about what happens—in functional terms—on these different “routes to action”. Ideomotor approaches claim that actions are selected with respect to their perceptual consequences. We report experiments that support the validity of the ideomotor principle and that, at the same time, show that it is subject to a far-reaching constraint: It holds for endogenously driven actions only! Our results suggest that the activity of the two “routes to action” is based on different types of learning: The activity of the system guiding stimulus-based actions is accompanied by stimulus-response (sensorimotor) learning, whereas the activity of the system controlling intention-based actions results in action-effect (ideomotor) learning.     

Two modes of sensorimotor integration in intention-based and stimulus-based actions

Human actions may be driven endogenously (to produce desired environmental effects) or exogenously (to accommodate to environmental demands). There is a large body of evidence indicating that these two kinds of action are controlled by different neural substrates. However, only little is known about what happens—in functional terms—on these different “routes to action”. Ideomotor approaches claim that actions are selected with respect to their perceptual consequences. We report experiments that support the validity of the ideomotor principle and that, at the same time, show that it is subject to a far-reaching constraint: It holds for endogenously driven actions only! Our results suggest that the activity of the two “routes to action” is based on different types of learning: The activity of the system guiding stimulus-based actions is accompanied by stimulus–response (sensorimotor) learning, whereas the activity of the system controlling intention-based actions results in action–effect (ideomotor) learning.     

Adaptive control of ideomotor effect anticipations

According to ideomotor theory, voluntary actions are selected and initiated by means of anticipated action effects. Prior experiments yielded evidence for these effect anticipations with response-effect (R-E) compatibility phenomena using blocked R-E relations. Daily actions, however, typically evoke different effects depending on the situational context. In the present study, we accounted for this natural variability and investigated R-E compatibility effects by a trial-by-trial variation of R-E compatibility relations. In line with recent observations regarding ideomotor learning, R-E compatibility influenced responding only when participants responded in free choice trials assuming that participants then adopted an intention-based action control mode. In contrast, R-E compatibility had no impact when participants responded according to imperative stimuli throughout the experiment, thus when participants adopted a stimulus-based action control mode. Interestingly, once an intention-based mode was established because of free choice trials within an experimental block, we observed response compatibility effects in free as well as forced choice trials. These findings extend and refine theoretical assumptions on different action control modes in goal-directed behavior and the specific contribution of ideomotor processes to intention-based action control.     

Sensory-based mechanism for delayed motor intention

Prospective motor learning (PML) can be defined as learning an action to be performed in the future. The privileged retrieval mechanism behind this delayed motor performance remains unknown. From a motor control and learning perspective, we may conceive of two forms of retrieval: a stimulus- and an intention-based control. Retrieval from intention-based control is based on the anticipation of intended sensory effects related to an action in order to select and control the appropriate motor procedure (i.e., the ideomotor mechanism). In contrast, in a stimulus-based control a connection between stimuli-features and their related action-features is stored in the memory and serves as the retrieval mechanism. In this view, action retrieval from external stimuli is based on the detection of events in the environment to perform the intended behaviour (i.e., the sensorimotor mechanism). In this study, we report an advantage in the action retrieval for participants who use an intention-based mode of control in comparison to a stimulus-based control. Furthermore, a control task reveals that the intention-based advantage is specific to PML. Our findings show that PML is benefited by mental anticipation of a sensory effect that is efficiently processed through an ideomotor mechanism to fulfil delayed motor intentions.     

Learning at any rate: action–effect learning for stimulus-based actions

Recent studies reported converging evidence for action–effect associations if participants adopted an intention-based action control mode in free choice conditions, whereas no evidence for action–effect associations was found when participants adopted a stimulus-based mode in forced choice conditions. However, it is not yet clear whether action control modes moderate acquisition or usage of action–effect associations. In the present experiment, two groups of participants underwent an acquisition phase consisting of either free or forced choice key presses that produced irrelevant, but contingent effect tones. In a subsequent test phase, participants freely chose the key to press after former effect tones were presented. A reliable consistency effect resulted for both the groups, i.e. participants preferred the key that produced the irrelevant tone in the preceding acquisition phase. In combination with prior findings, this consistency effect suggests that usage, but not acquisition of action–effect associations depends on an intention-based action control mode.     

观念运动理论：内涵与证据

人类日常动作有两种类型, 一是是对外界刺激的反应, 是一种自下而上的动作模式, 即感觉运动(sensorimotor)模式; 二是以人们头脑中的观念意图为基础, 由观念引导, 为了实现一个特定的目标而执行特定的动作, 是一种自上而下的动作模式, 即观念运动(ideomotor)模式。观念运动理论(ideomotor theory)所解释的就是以基于意图的动作。该理论经历了长期的演变, 一般动作执行与动作模仿领域内的行为与神经科学研究的证据初步证实了观念运动的理论构想与主要机制：共同编码机制与镜像神经机制。观念运动理论在贯通感知觉与动作方面具有重大意义, 由此还产生了共享环路模型(shared circuits model, SCM)等新近观点。此外, 观念运动理论还强调了目标和预期的重要地位。未来还需加强对动作与意图之间的通路, 以及动作的本体性效果等方面的研究。     

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.     

Contiguity and contingency in action-effect learning

According to the two-stage model of voluntary action, the ability to perform voluntary action is acquired in two sequential steps. Firstly, associations are acquired between representations of movements and of the effects that frequently follow them. Secondly, the anticipation or perception of an acquired action effect primes the movement that has been learnt to produce this effect; the acquired action-effect associations thus mediate the selection of actions that are most appropriate to achieve an intended action goal. If action-effect learning has an associative basis, it should be influenced by factors that are known to affect instrumental learning, such as the temporal contiguity and the probabilistic contingency of movement and effect. In two experiments, the contiguity or the contingency between key presses and subsequent tones was manipulated in various ways. As expected, both factors affected the acquisition of action-effect relations as assessed by the potency of action effects to prime the corresponding action in a later behavioral test. In particular, evidence of action-effect associations was obtained only if the effect of the action was delayed for no more than 1 s, if the effect appeared more often in the presence than in the absence of the action, or if action and effect were entirely uncorrelated but the effect appeared very often. These findings support the assumption that the control of voluntary actions is based on action-effect representations that are acquired by associative learning mechanisms.     

The temporal dynamics of the perceptual consequences of action-effect prediction

An essential aspect of voluntary action control is the ability to predict the perceptual effects of our actions. Although the influence of action-effect prediction on humans’ behavior and perception is unequivocal, it remains unclear when action-effect prediction is generated by the brain. The present study investigates the dynamics of action effect anticipation by tracing the time course of its perceptual consequences. Participants completed an acquisition phase during which specific actions (left and right key-presses) were associated with specific visual effects (upward and downward dots motion). In the test phase they performed a 2 AFC identification task in which they were required to indicate whether the dots moved upward or downward. To isolate any effects of action-effect prediction on perception, participants were presented with congruent and incongruent dot motion in which the association participants learned in the previous acquisition phase was respected and violated, respectively. Crucially, to assess the temporal dynamics of action prediction, congruent and incongruent stimuli were presented at different intervals before or after action execution. We observed higher sensitivity (d′) to motion discrimination in congruent vs. incongruent trials only when stimuli were presented from about 220 ms before the action to 280 ms after the action. The temporal dynamics of our effect suggest that action-effect prediction modulates perception at later stages of motor preparation.     

Coloring an action: Intending to produce color events eliminates the Stroop effect

The implications of an ideomotor approach to action control were investigated. In Experiment 1, participants made manual responses to letter stimuli and they were presented with response-contingent color patches, i.e., colored action effects. This rendered stimuli of the same color as an action's effect effective primes of that action, suggesting that bilateral associations were created between actions and the effects they produced. Experiment 2 combined this set-up with a manual Stroop task, i.e., participants responded to congruent, neutral, or incongruent color-word compounds. Standard Stroop effects were observed in a control group without action effects and in a group with target-incompatible action effects, but the reaction time Stroop effect was eliminated if actions produced target-compatible color effects (e.g., blue word --> left key --> blue patch). Experiment 3 did not replicate this interaction between target-effect compatibility and color-word congruency with color words as action effects, which rules out semantically based accounts. Theoretical implications for both action-effect acquisition and the Stroop effect are discussed. It is suggested that learning action effects, the features of which overlap with the target, allows and motivates people to recode their actions in ways that make them more stimulus-compatible. This provides a processing shortcut for translating the relevant stimulus into the correct response and, thus, shields processing from the impact of competing word distractors.     

Variable action effects: response control by context-specific effect anticipations

The ideomotor principle (IMP) claims that bidirectional associations between actions and their contingent effects are acquired so that voluntary actions are accessed by the anticipation of intended effects. Until now, evidence for the IMP exists only for stable action-effect relations. The present paper explores whether the IMP also holds true for the initiation of actions for which no unconditional contingent action-effect relations exist. Participants responded with left and right key presses in two different contexts. They selected the responses according to the vertical (context A) or horizontal (context B) position of a target. Responses were followed by short/fast movements of the target in context A and comparatively long/slow movements in context B. Consequently, each response produced short and long effects equally often in both contexts. Nevertheless, RTs decreased in contexts with short effects and increased in contexts with long effects. Data confirm that action-effect associations were acquired context-specifically and that the same actions were accessed by different effect anticipations.     

Action–effect anticipation in infant action control

There is increasing evidence that action effects play a crucial role in action understanding and action control not only in adults but also in infants. Most of the research in infants focused on the learning of action-effect contingencies or how action effects help infants to infer goals in other persons' actions. In contrast, the present research aimed at demonstrating that infants control their own actions by action-effect anticipation once they know about specific action-effect relations. About 7 and 9-month olds observed an experimenter demonstrating two actions that differed regarding the action-effect assignment. Either a red-button press or a blue-button press or no button press elicited interesting acoustical and visual effects. The 9-month olds produced the effect action at first, with shorter latency and longer duration sustaining a direct impact of action-effect anticipation on action control. In 7-month olds the differences due to action-effect manipulation were less profound indicating developmental changes at this age.     

How and why do infants imitate? An ideomotor approach to social and imitative learning in infancy (and beyond)

It has been proposed that already in infancy, imitative learning plays a pivotal role in the acquisition of knowledge and abilities. Yet the cognitive mechanisms underlying the acquisition of novel action knowledge through social learning have remained unclear. The present contribution presents an ideomotor approach to imitative learning (IMAIL) in infancy (and beyond) that draws on the ideomotor theory of action control and on recent findings of perception–action matching. According to IMAIL, the central mechanism of imitative and social learning is the acquisition of cascading bidirectional action–effect associations through observation of own and others’ actions. First, the observation of the visual effect of own actions leads to the acquisition of first-order action–effect associations, linking motor codes to the action’s typical visual effects. Second, observing another person’s action leads to motor activation (i.e., motor resonance) due to the first-order associations. This activated motor code then becomes linked to the other salient effects produced by the observed action, leading to the acquisition of (second-order) action–effect associations. These novel action–effect associations enable later imitation of the observed actions. The article reviews recent behavioral and neurophysiological studies with infants and adults that provide empirical support for the model. Furthermore, it is discussed how the model relates to other approaches on social-cognitive development and how developmental changes in imitative abilities can be conceptualized.     

On the timescale of stimulus-based action–effect learning

When performing an action, people pick up associations between their actions and the resulting consequences of that action, a phenomenon that has been termed response (R)–effect (E) learning. In the present study, we investigated incidental R–E learning in a forced-choice—that is, a stimulus (S)-based—acquisition mode. Specifically, the study examined at which timescale R–E learning evolves—that is, how many encounters are actually needed to form stable R–E associations. The learning of R–E associations was assessed in a subsequent test phase via effect-based response priming. Experiment 1 tested 4 different numbers of S–R–E repetitions for a 2–2–2 S–R–E mapping. Experiment 2 disentangled the contributions of S–E and R–E associations to the facilitating impact of effect-based response priming by means of a 4–2–4 S–R–E mapping. Experiment 3 investigated whether R–E associations can be picked up even when a given E cannot be unequivocally predicted based on the antecedent S in case of inconsistent S–R–E couplings. Together, the results of the present study clearly show that R–E learning occurs in a stimulus-based action mode and that it evolves very rapidly after only 12 S–R–E repetitions. Moreover, the present findings suggest that at least in this initial phase of learning, complete S–R–E consistency seems to be relevant for R–E learning.     

On the timescale of stimulus-based action-effect learning

When performing an action, people pick up associations between their actions and the resulting consequences of that action, a phenomenon that has been termed response (R)-effect (E) learning. In the present study, we investigated incidental R-E learning in a forced-choice-that is, a stimulus (S)-based-acquisition mode. Specifically, the study examined at which timescale R-E learning evolves-that is, how many encounters are actually needed to form stable R-E associations. The learning of R-E associations was assessed in a subsequent test phase via effect-based response priming. Experiment 1 tested 4 different numbers of S-R-E repetitions for a 2-2-2 S-R-E mapping. Experiment 2 disentangled the contributions of S-E and R-E associations to the facilitating impact of effect-based response priming by means of a 4-2-4 S-R-E mapping. Experiment 3 investigated whether R-E associations can be picked up even when a given E cannot be unequivocally predicted based on the antecedent S in case of inconsistent S-R-E couplings. Together, the results of the present study clearly show that R-E learning occurs in a stimulus-based action mode and that it evolves very rapidly after only 12 S-R-E repetitions. Moreover, the present findings suggest that at least in this initial phase of learning, complete S-R-E consistency seems to be relevant for R-E learning.     

Movements or targets: What makes an action in action–effect learning?

According to ideomotor theory, actions become linked to the sensory feedback they contingently produce, so that anticipating the feedback automatically evokes the action it typically results from. Numerous recent studies have provided evidence in favour of such action–effect learning but left an important issue unresolved. It remains unspecified to what extent action–effect learning is based on associating effect-representations to representations of the performed movements or to representations of the targets at which the behaviour aimed at. Two experiments were designed to clarify this issue. In an acquisition phase, participants learned the contingency between key presses and effect tones. In a following test phase, key–effect and movement–effect relations were orthogonally assessed by changing the hand–key mapping for one half of the participants. Experiment 1 showed precedence for target–effect over movement–effect learning in a forced-choice RT task. In Experiment 2, target–effect learning was also shown to influence the outcome of response selection in a free-choice task. Altogether, the data indicate that both movement–effect and target–effect associations contribute to the formation of action–effect linkages—provided that movements and targets are likewise contingently related to the effects.     

The role of anticipation and intention in the learning of effects of self-performed actions

The anticipative learning model for acquiring action-effect relations states that the acquisition of action-effect relations depends on processes that are part of action planning, in particular the anticipation of possible effects. Experiment 1 shows that response planning is indeed crucial for the learning of response effects. In this experiment distractors (tones) were presented either during response preparation or in the time interval between response execution and the presentation of a response effect. Response-effect learning was impaired when the distractors were presented during response preparation. The finding is consistent with the assumption that the distractors impaired the anticipation of potential effects and therefore reduced effect learning. In Experiment 2 all responses had two effects. Participants were instructed to produce one of the effects. Under this condition, response-effect learning was only found for the instructed effect, not for the non-instructed effect. The two experiments thus support the view that response-effect learning is selective and depends on the anticipation of potential effects during response planning. The results are discussed in terms of a model that explains both the learning of response-effect relations and the use of these effects for action control within the same theoretical framework.     

Action induction through action observation

Ideomotor movements may arise in individuals while they watch goal-directed actions or events. In a previous study we developed a paradigm for investigating ideomotor movements induced through watching the outcome of one's own action. In the present study we extended the paradigm to investigate both movements induced through watching the outcome of one's own as well as somebody else's action (player mode and observer mode respectively). We report three experiments, each with differing conditions for the player mode, but identical conditions for the observer mode. Results indicate that in both modes ideomotor movements are governed by two basic principles: Perceptual induction and intentional induction. In the player mode we replicated and extended previous findings, indicating dissociation between hand and head movements. In the observer mode no such dissociation was obtained. Our findings suggest that people perform, in their own actions, what they see being performed in other people's actions. Induction of action through observation can pertain to both the action's physical surface and underlying intentions. Furthermore, our results suggest that perceptual induction is ubiquitous but may be locally suspended for intentional action control. We discuss our results in the framework of theories invoking a strong overlap between representational structures for action perception and action planning.