Programming tool-use actions.

When humans plan to execute a tool-use action, they can only specify the bodily movement parameters by taking into account the external target or goal of the tool-use action and the target-movement mapping implemented by the tool. In this study, the authors used the movement precuing method to investigate how people prepare for actions made with tools. More specifically, they asked whether people would be able to specify the spatial target and the target-movement mapping of the tool-use action independently of each other, and to what degree they would be able to prepare these components in advance. In 3 experiments, they precued either the target or the target-movement mapping of tool-use actions involving either a compatible or an incompatible target-movement mapping. Results indicate that participants benefit from partial advance information about the target-movement mapping, whereas no significant effects were found for precuing the spatial target of the action. These results occurred regardless of whether the target-movement mapping was compatible or incompatible and provide evidence for the notion that the target-movement mapping of a tool-use action is part of its cognitive representation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

What is matched in direct matching? Intention attribution modulates motor priming.

Converging evidence has shown that action observation and execution are tightly linked. The observation of an action directly activates an equivalent internal motor representation in the observer (direct matching). However, whether direct matching is primarily driven by basic perceptual features of the observed movement or is influenced by more abstract interpretative processes is an open question. A series of behavioral experiments tested whether direct matching, as measured by motor priming, can be modulated by inferred action goals and attributed intentions. Experiment 1 tested whether observing an unsuccessful attempt to execute an action is sufficient to produce a motor-priming effect. Experiment 2 tested alternative perceptual explanations for the observed findings. Experiment 3 investigated whether the attribution of intention modulates motor priming by comparing motor-priming effects during observation of intended and unintended movements. Experiment 4 tested whether participants' interpretation of the movement as triggered by an external source or the actor's intention modulates the motor-priming effect by a pure instructional manipulation. Our findings support a model in which direct matching can be top-down modulated by the observer's interpretation of the observed movement as intended or not. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gestalt principles in the control of motor action.

We argue that 4 fundamental gestalt phenomena in perception apply to the control of motor action. First, a motor gestalt, like a perceptual gestalt, is holistic in the sense that it is processed as a single unit. This notion is consistent with reaction time results indicating that all gestures for a brief unit of action must be programmed prior to initiation of any part of the movement. Additional reaction time results related to initiation of longer responses are consistent with processing in terms of a sequence of indivisible motor gestalts. Some actions (e.g., many involving coordination of the hands) can be carried out effectively only if represented as a unitary gestalt. Second, a perceptual gestalt is independent of specific sensory receptors, as evidenced by perceptual constancy. In a similar manner a motor gestalt can be represented independently of specific muscular effectors, thereby allowing motor constancy. Third, just as a perceptual pattern (e.g., a Necker cube) is exclusively structured into only 1 of its possible configurations at any moment in time, processing prior to action is limited to 1 motor gestalt. Fourth, grouping in apparent motion leads to stream segregation in visual and auditory perception; this segregation is present in motor action and is dependent on the temporal rate. We discuss congruence of gestalt phenomena across perception and motor action (a) in relation to a unitary perceptual–motor code, (b) with respect to differences in the role of awareness, and (c) in conjunction with separate neural pathways for conscious perception and motor control. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Action compatibility effects are hedonically marked and have incidental consequences on affective judgment.

Recent results from Cannon, Hayes, and Tipper (2010) have established that the Action Compatibility Effect (ACE) is hedonically marked and elicits a genuine positive reaction. In this work, we aim to show that the hedonic marking of the ACE has incidental consequences on affective judgment. For this, we used the affective priming paradigm principle (for a review, see Musch & Klauer, 2003): participants have to respond, as quickly as they can, regarding the pleasantness or unpleasantness character of a target word. In the priming phase, we do not present an affective stimulus; however, we present two different graspable objects, one after the other. The handles of the graspable objects are shown either both on the same side (i.e., perceptual action compatibility) or not (i.e., perceptual action incompatibility). In addition, the orientation of the handles of the objects are either compatible (i.e., action compatibility) or not (i.e., action compatibility) with the response hand used for the word evaluation. Consistent with our hypothesis, participants responded faster to positive words after perceptual action compatibility and action compatibility (thus demonstrating the ACE) than after incompatibility conditions. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Object manipulation and motion perception: Evidence of an influence of action planning on visual processing.

In 3 experiments, the authors investigated the bidirectional coupling of perception and action in the context of object manipulations and motion perception. Participants prepared to grasp an X-shaped object along one of its 2 diagonals and to rotate it in a clockwise- or a counterclockwise direction. Action execution had to be delayed until the appearance of a visual go signal, which induced an apparent rotational motion in either a clockwise- or a counterclockwise direction. Stimulus detection was faster when the direction of the induced apparent motion was consistent with the direction of the concurrently intended manual object rotation. Responses to action-consistent motions were also faster when the participants prepared the manipulation actions but signaled their stimulus detections with another motor effector (i.e., with a foot response). Taken together, the present study demonstrates a motor-visual priming effect of prepared object manipulations on visual motion perception, indicating a bidirectional functional link between action and perception beyond object-related visuomotor associations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Experience matters: The impact of doing versus watching on infants' subsequent perception of tool-use events.

Prior work suggests that active experience affects infants' understanding of simple actions. The present studies compared the impact of active and observational experience on infants' ability to identify the goal of a novel tool-use event. Infants either received active training and practice in using a cane to retrieve an out-of-reach toy or had matched observational experience before taking part in a habituation paradigm that we used to assess infants' ability to identify the goal of another person's tool-use acts. Active training alone facilitated 10-month-old infants' ability to identify the goal of the tool-use event. Active experience using tools may enable infants to build motor representations of tool-use events that subsequently guide action perception and support action understanding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Can intertrial effects of features and dimensions be explained by a single theory?

This study investigated feature- and dimension-based intertrial effects in visual search for a pop-out target. The 2 prominent theories explaining intertrial effects, priming of pop-out and dimension weighting, both assume that repeating the target from the previous trial facilitates attention shifts to the target, whereas changing the target leads to attentional switch costs. In contrast, the results from the present study indicate that intertrial effects from changing features and dimensions involve different underlying mechanisms: Eye movement recordings showed that feature priming reliably modulates the speed of visually selecting the target, whereas changing the target dimension interferes only with processes after selection of the search target. Further experiments with a size and orientation singleton target showed that feature priming does not consist in carryover effects of target activation or nontarget inhibition, contrary to standard assumptions in visual search. Instead, priming effects critically depended on whether a coarse relation between target and nontarget features (e.g., smaller or larger) was repeated or reversed across trials. These results suggest the need to modify current models of priming in visual search. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Action semantic knowledge about objects is supported by functional motor activation.

The present study assessed the functional organization of action semantics by asking subjects to categorize pictures of an actor holding objects with a correct or incorrect grip at either a correct or incorrect goal location. Overall, reaction times were slower if the object was presented with an inappropriate posture, and this effect was stronger for goal violations compared with grip violations (Experiment 1). In addition, the retrieval of action semantics was found accompanied by the implicit activation of motor representations. Body-related objects (e.g., cup) were classified faster when a movement toward the subject’s body was required, whereas world-related objects (e.g., pincers) were responded to faster with a movement in the opposite direction (Experiments 2 and 3). In contrast, when subjects were required to retrieve only visual semantics (Experiment 4), no interference effects of postural information were observed, and motor representations were only partially activated. These findings suggest that action semantics can be accessed independently from visual semantics and that the retrieval of action semantics is supported by functional motor activation reflecting the prototypical use of an object. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sticky Rules: Integration Between Abstract Rules and Specific Actions.

The authors manipulated repetitions and/or changes of abstract response rules and the specific stimulus- response (S-R) associations used under these rules. Experiments 1 and 2, assessing trial-to-trial priming effects, showed that repetition of complete S-R couplings produced only benefits when the rule also repeated (i.e., rule-S-R conjunctions) but costs when identical S-R couplings repeated while rules changed. In Experiments 3 and 4, the authors manipulated amount of experience with specific rule-S-R conjunctions and demonstrated integration between rules and S-R couplings in terms of cumulative practice effects. However, unlike short-term priming effects, cumulative practice supported generalization of experience with specific S-R couplings across rule boundaries (Experiment 4). Results are discussed in terms of constraints on models of hierarchical control and in terms of qualitatively different ways in which people profit from very recent experiences (i.e., all-or-none access to working memory representations) versus cumulative experience (i.e., similarity-based retrieval from long-term memory). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The early development of object knowledge: A study of infants’ visual anticipations during action observation.

This study examined the developing object knowledge of infants through their visual anticipation of action targets during action observation. Infants (6, 8, 12, 14, and 16 months) and adults watched short movies of a person using 3 different everyday objects. Participants were presented with objects being brought either to a correct or to an incorrect target location (e.g., cup to mouth, phone to ear vs. cup to ear, brush to mouth). When observing the action sequences, infants as well as adults showed anticipatory fixations to the target areas of the displayed actions. For all infant age-groups, there were differences in anticipation frequency between functional and nonfunctional object–target combinations. Adults exhibited no effect of object–target combination, possibly because they quickly learned and flexibly anticipated the target area of observed actions, even when they watched objects being brought to incorrect target areas. Infants, however, had difficulties anticipating to incorrect target locations for familiar objects. Together, these findings suggest that by 6 months of age, infants have acquired solid knowledge about objects and the actions associated with them. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Beliefs about affirmative action: A test of the group self-interest and racism beliefs models.

Two models of affirmative action attitudes (i.e., group self-interest and racism beliefs) were examined among a sample of racially diverse college students. Open-ended questions were included to provide students an opportunity to elaborate on their beliefs about affirmative action and beliefs about the existence of racial discrimination. Findings from logistic regression analysis on a subsample (n = 376) provide support for both models; race (a proxy for group self-interest) and racism beliefs (as measured by the Color-Blind Racial Attitudes Scale [CoBRAS] and an the open-ended question) helped predict endorsement of affirmative action in theoretically expected ways. Asian, Latino, and Black students were more likely to view affirmative action as helpful compared to their White counterparts, and limited awareness of institutional racism (i.e., higher CoBRAS scores) was associated with antiaffirmative action arguments. Follow-up analysis, however, provided support for the superiority of the racism beliefs model as measured by the CoBRAS in predicting affirmative action beliefs over the group-interest model. Limitations and implications for future research are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Inhibition in language switching: What is inhibited when switching between languages in naming tasks?

When people switch between languages, inhibition of currently irrelevant languages is assumed to occur. The authors examined inhibition of irrelevant languages with a cued language-switching paradigm. A cue indicated in which of 3 languages (German, English, or French) a visual stimulus was to be named. In 2 experiments, the authors found that naming latencies were increased in n-2 language repetitions (e.g., German/English/German) compared with in n-2 language nonrepetitions (e.g., French/English/German). This difference (n-2 repetition costs) indicates persisting inhibition of abandoned languages. It is important to note that n-2 language-repetition costs also occurred in conditions in which the language but not the cue (Experiment 1) or the stimulus/response set (Experiment 2) repeated from trial n-2 to trial n. These data demonstrate that inhibition is not restricted to a specific cue or stimulus/response set. Rather, the data suggest more global inhibitory processes that affect the mental representation of competing languages. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of agency on movement interference during observation of a moving dot stimulus.

Human movement performance is subject to interference if the performer simultaneously observes an incongruent action. It has been proposed that this phenomenon is due to motor contagion during simultaneous movement performance-observation, with coactivation of shared action performance and action observation circuitry in the premotor cortex. The present experiments compared the interference effect during observation of a moving person with observation of moving dot stimuli: The dot display followed either a biologically plausible or implausible velocity profile. Interference effects due to dot observation were present for both biological and nonbiological velocity profiles when the participants were informed that they were observing prerecorded human movement and were absent when the dot motion was described as computer generated. These results suggest that the observer's belief regarding the origin of the dot motion (human-computer generated) modulates the processing of the dot movement stimuli on their later integration within the motor system, such that the belief regarding their biological origin is a more important determinant of interference effects than the stimulus kinematics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Timing of EEG-based cursor control

Recent studies show that humans can learn to control the amplitude of electroencephalography (EEG) activity in specific frequency bands over sensorimotor cortex and use it to move a cursor to a target on a computer screen. EEG-based communication could be a valuable new communication and control option for those with severe motor disabilities. Realization of this potential requires detailed knowledge of the characteristic features of EEG control. This study examined the course of EEG control after presentation of a target. At the beginning of each trial, a target appeared at the top or bottom edge of the subject's video screen and 1 sec later a cursor began to move vertically as a function of EEG amplitude in a specific frequency band. In well-trained subjects, this amplitude was high at the time the target appeared and then either remained high (i.e., for a top target) or fell rapidly (i.e., for a bottom target). Target-specific EEG amplitude control began 0.5 sec after the target appeared and appeared to wax and wane with a period of approximately 1 sec until the cursor reached the target (i.e., a hit) or the opposite edge of the screen (i.e., a miss). Accuracy was 90% or greater for each subject. Top-target errors usually occurred later in the trial because of failure to reach and/or maintain sufficiently high amplitude, whereas bottom-target errors usually occurred immediately because of failure to reduce an initially high amplitude quickly enough. The results suggest modifications that could improve performance. These include lengthening the intertrial period, shortening the delay between target appearance and cursor movement, and including time within the trial as a variable in the equation that translates EEG into cursor movement.     

The Costs of Changing the Representation of Action: Response Repetition and Response-Response Compatibility in Dual Tasks.

In 5 experiments, the authors investigated the costs associated with repeating the same or a similar response in a dual-task setting. Using a psychological refractory period paradigm, they obtained response-repetition costs when the cognitive representation of a specific response (i.e., the category-response mapping) changed (Experiment 1) but benefits when it did not change (Experiment 2). The analogous pattern of results was found for conceptually similar (i.e.. compatible) responses. Response-response compatibility costs occurred when the cognitive representations of the compatible responses were different (Experiments 3A & 3B), but compatibility benefits occurred when they were the same (Experiment 4). The authors interpret the costs of repeating an identical or compatible response in terms of a general mechanism of action selection that involves coding the task-specific meaning of a response. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dissociating cue-related and task-related processes in task inhibition: Evidence from using a 2:1 cue-to-task mapping.

Performance of task sequences is assumed to rely on activation and inhibition of tasks. An empirical marker of task inhibition is the so-called n - 2 repetition cost, which is assessed by comparing performance in trial n - 2 task repetitions (i.e., ABA) with that in n - 2 task switches (i.e., CBA). Current theoretical accounts assume that inhibition acts on the level of task representations (i.e., task sets). However, another potential target of task inhibition could be the representation of the task cue. To decide between these two alternatives, the authors used a 2:1 cue-to-task mapping design. They found significant n - 2 task repetition costs both with n - 2 cue repetitions and n - 2 cue switches. These costs were about equal (Experiment 1), and this data pattern was found for both short and long cuing intervals (Experiment 2). Together, the data suggest that task inhibition acts on task sets and not on cue representations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Imitative response tendencies following observation of intransitive actions.

Clear and unequivocal evidence shows that observation of object affordances or transitive actions facilitates the activation of a compatible response. By contrast, the evidence showing response facilitation following observation of intransitive actions is less conclusive because automatic imitation and spatial compatibility have been confounded. Three experiments tested whether observation of a finger movement (i.e., an intransitive action) in a choice reaction-time task facilitates the corresponding finger movement response because of imitation, a common spatial code, or some combination of both factors. The priming effects of a spatial and an imitative stimulus were tested in combination (Experiment 1), in opposition (Experiment 2), and independently (Experiment 3). Contrary to previous findings, the evidence revealed significant contributions from both automatic imitation and spatial compatibility, but the priming effects from an automatic tendency to imitate declined significantly across a block of trials whereas the effects of spatial compatibility remained constant or increased slightly. These differential effects suggest that priming associated with automatic imitation is mediated by a different regime than priming associated with spatial compatibility. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Concreteness-dependent associative priming: Separate lexical organization for concrete and abstract words.

Four experiments used associated, unrelated, and neutral ({blank}–word) pairs that varied on prime and target concreteness. In Experiment 1, associated targets were named faster than neutral targets when primes and targets were homogeneous for concreteness (i.e., concrete–concrete or abstract–abstract), but not when they were heterogeneous (i.e., concrete–abstract or abstract–concrete). Experiments 2 and 3, using lexical decision, showed priming for all pairs irrespective of prime and target concreteness. In Experiment 4, the prime was presented for 16.7 ms, followed immediately by a 168-ms random letter mask. Lexical decision times showed priming similar to that in Experiment 1. If priming in Experiments 1 and 4 reflected lexical processes, whereas priming in Experiments 2 and 3 entailed postlexical processes, then lexical processes may be functionally distinct for concrete versus abstract words. These findings are more consistent with dual-coding than common-coding explanations of concreteness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On the (un)conditionality of automatic attitude activation: The valence proportion effect.

Affective priming studies have shown that participants are faster to pronounce affectively polarized target words that are preceded by affectively congruent prime words than affectively polarized target words that are preceded by affectively incongruent prime words. We examined whether affective priming of naming responses depends on the valence proportion (i.e., the proportion of stimuli that are affectively polarized). In one group of participants, experimental trials were embedded in a context of filler trials that consisted of affectively polarized stimulus materials (i.e., high valence proportion condition). In a second group, the same set of experimental trials was embedded in a context of filler trials consisting of neutral stimuli (i.e., low valence proportion condition). Results showed that affective priming of naming responses was significantly stronger in the high valence proportion condition than in the low valence proportion condition. We conclude that (a) subtle aspects of the procedure can influence affective priming of naming responses, (b) finding affective priming of naming responses does not allow for the conclusion that affective stimulus processing is unconditional, and (c) affective stimulus processing depends on selective attention for affective stimulus information. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Episodic retrieval in negative priming and repetition priming.

Subjects identified target letters flanked by incompatible distractor letters (e.g., ABA). Distractor onset was randomly simultaneous with target onset or was delayed by 400 ms. In Experiment 1, one third of probe-trial targets were identical to the preceding prime-trial distractor. Responses were slower to repeated letters than to unrepeated letters (negative priming) only when prime and probe trials shared the same distractor-onset conditions. In Experiment 2, one third of probe-trial targets were identical to the preceding prime-trial target. Significant facilitation (repetition priming) occurred for repeated targets in all conditions but was again greater when prime and probe trials shared the same distractor-onset conditions. The results strongly support episodic retrieval theories of both negative priming and repetition priming and suggest that a common mechanism underlies both phenomena. (PsycINFO Database Record (c) 2010 APA, all rights reserved)