Effect of an unrelated fluent action on word recognition: A case of motor discrepancy.

It is now well established that motor fluency affects cognitive processes, including memory. In two experiments participants learned a list of words and then performed a recognition task. The original feature of our procedure is that before judging the words they had to perform a fluent gesture (i.e., typing a letter dyad). The dyads comprised letters located on either the right or left side of the keyboard. Participants typed dyads with their right or left index finger; the required movement was either very small (dyad composed of adjacent letters, Experiment 1) or slightly larger (dyad composed of letters separated by one key, experiment 2). The results show that when the gesture was performed in the ipsilateral space the probability of recognizing a word increased (to a lesser extent it is the same with the dominant hand, experiment 2). Moreover, a binary regression logistic highlighted that the probability of recognizing a word was proportional to the speed by which the gesture was performed. These results are discussed in terms of a feeling of familiarity emerging from motor discrepancy.

Valence activates motor fluency simulation and biases perceptual judgment.

The concept of motor fluency, defined as the positive marking associated with the easy realisation of a movement, is used to explain the various compatibility effects observed between emotional valence and lateral space. In this work, we propose that these effects arise from the motor fluency simulation induced by emotionally positive stimuli. In a perceptual line bisection task (Landmark task) we primed each trial with an emotionally positive word, negative word, neutral word or no word before asking participants to verbally indicate the side of the vertical mark on the horizontal line (Experiment 1) or to indicate the longest side of the line (Experiment 2). After positive words and for bisected lines, participants' responses were biased towards their dominant side for both right- and left-handers and similarly under the two different instructions. As movements of the dominant hand or in the dominant hemispace have been described as the most fluent lateral actions, this result supports our hypothesis that positive stimuli induce a mental simulation of fluent lateral movements. Furthermore, the replication of the effect under opposite instructions between the two experiments is in line with an explanation in terms of a bias in response selection rather than variations in perceptual content.

Word-to-picture recognition is a function of motor components mappings at the stage of retrieval.

Embodied approaches of cognition argue that retrieval involves the re-enactment of both sensory and motor components of the desired remembering. In this study, we investigated the effect of motor action performed to produce the response in a recognition task when this action is compatible with the affordance of the objects that have to be recognised. In our experiment, participants were first asked to learn a list of words referring to graspable objects, and then told to make recognition judgements on pictures. The pictures represented objects where the graspable part was either pointing to the same or to the opposite side of the "Yes" response key. Results show a robust effect of compatibility between objects affordance and response hand. Moreover, this compatibility improves participants' ability of discrimination, suggesting that motor components are relevant cue for memory judgement at the stage of retrieval in a recognition task. More broadly, our data highlight that memory judgements are a function of motor components mappings at the stage of retrieval.

When "good" is not always right: effect of the consequences of motor action on valence-space associations.

Since the work of Casasanto (2009), it is now well established that valence and laterality are associated. Participants tend to prefer objects presented on their dominant side over items presented on their non-dominant side, and to place good items on their dominant side and bad items on the other side. Several studies highlight that those associations of valence and laterality are accounted for by the greater motor fluency of the dominant hand and various studies noted that these associations could be reversed depending on the way people interact with their environment. Consistently with the Theory of Event Coding, the aim of this work is to show that the consequences of motor actions could also reverse the associations between valence and laterality. Thus, if participants had to place two animals (one good, one bad) on two supports, one stable (no risk of falling), one unstable (risk of falling), we hypothesized that the good item would be placed on the stable support, regardless of the side where it would be put (i.e., on the dominant or non-dominant side). We expected the opposite for the bad item. The results of two experiments are consistent with this prediction and support the claim that the consequences of motor action bias the hedonic connotation of our dominant side.

Sensory-motor properties of past actions bias memory in a recognition task.

The aim of this study was to show that sensory-motor consequences of past actions form part of memory trace components cued by current experience. In a first task participants had to learn a list of words. Then in a guessing task they played against the computer. Finally, in a recognition task, they had to judge if the words were or were not present in the learning task. Words appeared either in the colour associated with success or failure in the guessing task, or in a non-informative colour. In the first experiment, results show that when the words to be judged were in the colour associated with success, participants answered faster and produced more "old" responses than when the words to be judged were in the colour associated with failure in the previous task. Moreover, when the words to be judged were in the colour associated with failure, participants were slower and produced less "old" responses than when the words were in a colour not informative of success or failure. The second experiment confirms that the results obtained in Experiment 1 were linked to the sensory-motor consequences of past actions associated with the colour and not to the colour itself.

Valence-space compatibility effects depend on situated motor fluency in both right- and left-handers.

According to the body specificity hypothesis, the way we interact with our environment participates in our conceptualization of concepts and word meanings. For instance, valence is associated to horizontal space because of the motor fluency by which one acts with one's dominant hand. We propose that the decisive factor in the compatibility effects between valence and lateral actions is the interaction between the fluency of response movement and the situational constraints of the task. In a valence judgement task with positive and negative words, right-handers (Experiment 1) and left-handers (Experiment 2) responded with lateralized actions of either their dominant or their nondominant hand. To do so, we used a response device that was either congruent or noncongruent with the fluency of the response hand. Results highlighted that when the response device was congruent with the fluency of the responding hand, response times to positive evaluations were shorter than those to negative evaluations. Conversely, when the response device was noncongruent with the fluency of the responding hand, we observed faster responses for negative evaluations than for positive evaluations. Furthermore, we obtained similar patterns for right- and left-handers, supporting the idea that compatibility effects are driven by the situated fluency of the responding hand.

Biases in evaluation of neutral words due to motor compatibility effect.

This study aims to demonstrate the effect of action fluency on emotional evaluation, specifically to show that neutral words can be evaluated positively or negatively depending on motor activity and evaluative setting. Right-handers naturally tend to associate positive (negative) valence to the right (left) part of space (Casasanto, 2009). We extend these associations to lateralized behaviors by studying the combined effect of motor fluency of lateral arm movements and the evaluative scale on the subjective evaluation of neutral words. Three experiments evidenced that, for right-handers, the realization of fluent rightward arm movements and the use of an evaluative scale congruent with their valence/laterality associations (left negative, right positive) led to a positive evaluation of neutral words, while non-fluent leftward movements and an incongruent scale led to a negative evaluation. This study demonstrates that emotion-action associations are experience-based, and influenced by functional and situational constraints.