Visual enhancement of touch and the bodily self

We experience our own body through both touch and vision. We further see that others’ bodies are similar to our own body, but we have no direct experience of touch on others’ bodies. Therefore, relations between vision and touch are important for the sense of self and for mental representation of one’s own body. For example, seeing the hand improves tactile acuity on the hand, compared to seeing a non-hand object. While several studies have demonstrated this visual enhancement of touch (VET) effect, its relation to the ‘bodily self’, or mental representation of one’s own body remains unclear. We examined whether VET is an effect of seeing a hand, or of seeing my hand, using the rubber hand illusion. In this illusion, a prosthetic hand which is brushed synchronously—but not asynchronously—with one’s own hand is felt to actually be one’s hand. Thus, we manipulated whether or not participants felt like they were looking directly at their hand, while holding the actual stimulus they viewed constant. Tactile acuity was measured by having participants judge the orientation of square-wave gratings. Two characteristic effects of VET were observed: (1) cross-modal enhancement from seeing the hand was inversely related to overall tactile acuity, and (2) participants near sensory threshold showed significant improvement following synchronous stroking, compared to asynchronous stroking or no stroking at all. These results demonstrate a clear functional relation between the bodily self and basic tactile perception.     

Schizotypal personality traits and prediction of one's own movements in motor control: what causes an abnormal sense of agency?

Background. Positive schizophrenic symptoms, especially passivity phenomena, including auditory hallucinations, may be caused by an abnormal sense of agency, which people with schizotypal personality traits also tend to exhibit. A sense of agency asserts that it is oneself who is causing or generating an action. It is possible that this abnormal sense of self-agency is attributable to the abnormal prediction of one’s own movements in motor control. Method. We conducted an experiment using the “disappeared cursor” paradigm in which non-clinical, healthy participants were required to click on a target using an invisible mouse cursor. Prediction error was defined as the distance between the target and the click point. Results. The results showed that schizotypal personality traits, but not depressive or anxious traits, were correlated with deficits in predicting movements of the subjects’ left hand. In particular, auditory hallucination proneness had the strongest relationship with movement prediction error. In this report, we also discuss the error tendency (overestimations or underestimations of one’s own movements). Conclusions. This finding is in accordance with the idea that passivity phenomena or proneness may be caused by the abnormal prediction of one’s own actions or movements.     

Intentionality as a constituting condition for the own self—and other selves

Introspectively, the awareness of actions includes the awareness of the intentions accompanying them. Therefore, the awareness of self-generated actions might be expected to differ from the awareness of other-generated actions to the extent that access to one’s own and to other’s intentions differs. However, we recently showed that the perceived onset times of self- vs. other-generated actions are similar, yet both are different from comparable events that are conceived as being generated by a machine. This similarity raises two interesting possibilities. First we could infer the intentions of others from their actions. Second and more radically, we could equally infer our own intentions from the actions we perform rather than sense them. We present two new experiments which investigate the role of action effects in the awareness of self- and other-generated actions by means of measuring the estimated onset time. The results show that the presence of action effects is necessary for the similarity of awareness of self- and other-generated actions.     

The impact of information from similar or different advisors on judgment

People rely on others’ advice to make judgments on a daily basis. In three studies, we examine the differential impacts of similarity between the source of that advice and the person making the judgment in two settings: judging others’ behavior and judging one’s own actions. We find that similarity interacts with the target of the judgment. In particular, information received from a different advisor is more heavily weighed than from a similar advisor in judging others’ actions, but information from a similar advisor is more heavily weighed than from a different advisor in judging one’s own. We provide two potential explanations for this interaction, difficulty of the judgment and informativeness of the advice. Our analyses show a moderated mediating role of informativeness and difficulty in the relationship between the advisor’s similarity by judgment type interaction and advice use.     

Effects of another person’s fair treatment on one’s own emotions and behaviors: The moderating role of how much the other cares for you

This research examined whether the extent of fair treatment of another affects one’s own reactions and whether helpful and supportive behavior from this other towards oneself moderates this impact. We predicted fair treatment of the other would affect the participant’s own emotions and behaviors with respect to a common task, but only if this other was willing to give help and support. In addition, we expected that positive or negative emotions would underlie, respectively, a participant’s willingness to cooperate or their willingness to leave the task. Results from a scenario experiment, a cross-sectional survey, and a laboratory experiment supported our predictions. We conclude that how fairly another is treated matters in its effects on one’s emotional and behavioral reactions and that procedural justice for others can also be considered important organizational information in shaping one’s own feelings and actions for employees.     

The processing of auditory and visual recognition of self-stimuli

This study examined self-recognition processing in both the auditory and visual modalities by determining how comparable hearing a recording of one’s own voice was to seeing photograph of one’s own face. We also investigated whether the simultaneous presentation of auditory and visual self-stimuli would either facilitate or inhibit self-identification. Ninety-one participants completed reaction-time tasks of self-recognition when presented with their own faces, own voices, and combinations of the two. Reaction time and errors made when responding with both the right and left hand were recorded to determine if there were lateralization effects on these tasks. Our findings showed that visual self-recognition for facial photographs appears to be superior to auditory self-recognition for voice recordings. Furthermore, a combined presentation of one’s own face and voice appeared to inhibit rather than facilitate self-recognition and there was a left-hand advantage for reaction time on the combined-presentation tasks.     

The illusion of courage in social predictions: Underestimating the impact of fear of embarrassment on other people

The results of two experiments support the thesis that emotional perspective taking entails two judgments: a prediction of one’s own preferences and decisions in a different emotional situation, and an adjustment of this prediction to accommodate perceived differences between self and others. Participants overestimated others’ willingness to engage in embarrassing public performances—miming (Experiment 1) and dancing (Experiment 2)—in exchange for money. Consistent with a dual judgment model, this overestimation was greater among participants facing a hypothetical rather than a real decision to perform. Further, participants’ predictions of others’ willingness to perform were more closely correlated with self-predictions than with participants’ estimates of others’ thoughts about the costs and benefits of performing.     

The self in action effects: selective attenuation of self-generated sounds

The immediate experience of self-agency, that is, the experience of generating and controlling our actions, is thought to be a key aspect of selfhood. It has been suggested that this experience is intimately linked to internal motor signals associated with the ongoing actions. These signals should lead to an attenuation of the sensory consequences of one’s own actions and thereby allow classifying them as self-generated. The discovery of shared representations of actions between self and other, however, challenges this idea and suggests similar attenuation of one’s own and other’s sensory action effects.Here, we tested these assumptions by comparing sensory attenuation of self-generated and observed sensory effects. More specifically, we compared the loudness perception of sounds that were either self-generated, generated by another person or a computer. In two experiments, we found a reduced perception of loudness intensity specifically related to self-generation. Furthermore, the perception of sounds generated by another person and a computer did not differ from each other. These findings indicate that one’s own agentive influence upon the outside world has a special perceptual quality which distinguishes it from any sort of external influence, including human and non-human sources. This suggests that a real sense of self-agency is not a socially shared but rather a unique and private experience.     

Attributions and other inferences: Processing information about the self versus others

This study focuses on the attributional inferences involved in the comprehension of behaviors and on possible differences between the process of comprehending one's own behaviors and those of another person. Both the content of attributional judgments and the time taken to make the judgments were measured, in a design involving the comprehension of behaviors that were high or low in desirability and distinctiveness and that were understood as the subject's own versus another person's. Results show that the inferential processes in the comprehension of one's own and another's behavior are generally similar. Exceptions are where organized knowledge about the self (a self-schema) is brought into use and where differences in “perspective” between self and other influence processing. Discussion centers on the implications of the results for theories of comprehension and inference, including extensions needed to handle the self/other distinction.     

I move, therefore I am: a new theoretical framework to investigate agency and ownership

The neurocognitive structure of the acting self has recently been widely studied, yet is still perplexing and remains an often confounded issue in cognitive neuroscience, psychopathology and philosophy. We provide a new systematic account of two of its main features, the sense of agency and the sense of ownership, demonstrating that although both features appear as phenomenally uniform, they each in fact are complex crossmodal phenomena of largely heterogeneous functional and (self-)representational levels. These levels can be arranged within a gradually evolving, onto- and phylogenetically plausible framework which proceeds from basic non-conceptual sensorimotor processes to more complex conceptual and meta-representational processes of agency and ownership, respectively. In particular, three fundamental levels of agency and ownership processing have to be distinguished: The level of feeling, thinking and social interaction. This naturalistic account will not only allow to “ground the self in action”, but also provide an empirically testable taxonomy for cognitive neuroscience and a new tool for disentangling agency and ownership disturbances in psychopathology (e.g. alien hand, anarchic hand, anosognosia for one’s own hemiparesis).     

Action observation modulates auditory perception of the consequence of others' actions

We can easily discriminate self-produced from externally generated sensory signals. Recent studies suggest that the prediction of the sensory consequences of one’s own actions made by forward model can be used to attenuate the sensory effects of self-produced movements, thereby enabling a differentiation of the self-produced sensation from the externally generated one. The present study showed that attenuation of sensation occurred both when participants themselves performed a goal-directed action and when they observed experimenter performing the same action, although they clearly reported that the tones were produced by other during action observation and by themselves during their own action. These results suggest that sensory prediction of action modulates ongoing auditory processing irrespective of who produces the sounds and that the explicit judgment of agency does not necessarily rely on the same mechanisms on which implicit perceptual measures such as sensory attenuation rely.     

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.     

Speech-associated gestures, Broca’s area, and the human mirror system

Speech-associated gestures are hand and arm movements that not only convey semantic information to listeners but are themselves actions. Broca’s area has been assumed to play an important role both in semantic retrieval or selection (as part of a language comprehension system) and in action recognition (as part of a “mirror” or “observation–execution matching” system). We asked whether the role that Broca’s area plays in processing speech-associated gestures is consistent with the semantic retrieval/selection account (predicting relatively weak interactions between Broca’s area and other cortical areas because the meaningful information that speech-associated gestures convey reduces semantic ambiguity and thus reduces the need for semantic retrieval/selection) or the action recognition account (predicting strong interactions between Broca’s area and other cortical areas because speech-associated gestures are goal-direct actions that are “mirrored”). We compared the functional connectivity of Broca’s area with other cortical areas when participants listened to stories while watching meaningful speech-associated gestures, speech-irrelevant self-grooming hand movements, or no hand movements. A network analysis of neuroimaging data showed that interactions involving Broca’s area and other cortical areas were weakest when spoken language was accompanied by meaningful speech-associated gestures, and strongest when spoken language was accompanied by self-grooming hand movements or by no hand movements at all. Results are discussed with respect to the role that the human mirror system plays in processing speech-associated movements.     

Unconscious modulation of the conscious experience of voluntary control

How does the brain generate our experience of being in control over our actions and their effects? Here, we argue that the perception of events as self-caused emerges from a comparison between anticipated and actual action-effects: if the representation of an event that follows an action is activated before the action, the event is experienced as caused by one's own action, whereas in the case of a mismatch it will be attributed to an external cause rather than to the self. In a subliminal priming paradigm we show that participants overestimated how much control they had over objectively uncontrollable stimuli, which appeared after free- or forced-choice actions, when a masked prime activated a representation of the stimuli immediately before each action. This prime-induced control-illusion was independent from whether primes were consciously perceived. Results indicate that the conscious experience of control is modulated by unconscious anticipations of action-effects.     

Who's calling the shots? Intentional content and feelings of control

Based on Pacherie’s dynamic theory of intentions, this study investigated how the way an intention is formed and sustained affects action performance and the experience of control during acting. In Experiment 1, task-irrelevant verbal commands were given while participants responded to stimuli in a two-choice reaction time (RT) task. The commands referred to an action goal congruent or incongruent with the actor’s current intention, or ordered the initiation or abortion of the action. In Experiment 2, the same commands were given as participants freely chose between two actions. The distractors affected performance in the reactive task only. In both experiments, feelings of control were based on movement parameters as well as perceived (mis)matches between distractors and intended actions. These findings suggest that the way an intention is implemented affects how well it can be shielded against external perturbations and how much one feels in control.     

Seeing oneself in one’s choices: Construal level and self-pertinence of electoral and consumer decisions

Building on previous research examining the implications for self-regulation and decision making of construing action at varying levels of abstraction, the authors proposed that construing action in terms of its abstract purposes facilitates orienting one’s decisions toward the standards, characteristics, and goals that define one’s desired self-concept. Consistent with this proposal, desiring for oneself a political candidate’s personal qualities predicted evaluating favorably (in Study 1) and voting for (in Study 2) that candidate to a greater extent among participants focused on the distal future (and presumably construing action at a relatively high-level of abstraction) than the proximal future (and presumably construing action at a relatively low-level of abstraction). Moreover, individuals chronically construing action in high-level terms responded more favorably to advertisements appealing to their desired self-concept (in Study 3) than to product quality. These findings’ implications for decision making are discussed.     

The "sense of agency" and its underlying cognitive and neural mechanisms

The sense of agency is a central aspect of human self-consciousness and refers to the experience of oneself as the agent of one’s own actions. Several different cognitive theories on the sense of agency have been proposed implying divergent empirical approaches and results, especially with respect to neural correlates. A multifactorial and multilevel model of the sense of agency may provide the most constructive framework for integrating divergent theories and findings, meeting the complex nature of this intriguing phenomenon.     

Self awareness and the body image

What mental representations give us the sense of our body as a unique object in the world? We investigated this issue in the context of the rubber hand illusion (RHI), an illusion of body image in which a prosthetic hand brushed synchronously, but not asynchronously, with one’s own hand is perceived as actually being one’s hand. We conducted a large-scale study of the RHI, and used psychometric analysis to reveal the structure of the subjective experience of embodiment [Longo et al. (2008). What is embodiment? A psychometric approach. Cognition,107, 978-998]. Here, we use this dataset to investigate the relation between incorporation of a rubber hand into the body image and the perceived similarity between the participant’s hand and the rubber hand. Objective similarity (as measured by skin luminance, hand shape, and third-person similarity ratings) did not appear to influence participants’ experience of the RHI. Conversely, incorporation of the rubber hand into the body image did affect the similarity that participants perceived between their own hand and the rubber hand. Participants who had experienced the RHI perceived their hand and the rubber hand as significantly more similar than participants who had not experienced the illusion. That is, embodiment leads to perceived similarity, but perceived similarity does not lead to embodiment. Furthermore, similarity ratings following the illusion were selectively correlated with some components of embodiment, but not with others. These results suggest an important role of a mental body image in the perception of the relation between the self and others.     

Self-esteem and cognitive consistency effects on self-other evaluation

Reactions to bogus evaluations of one's self, either positively or negatively discrepant from one's own self-evaluation, were investigated among subjects differing in self-ideal discrepancy. All subjects exhibited greater acceptance of the source of favorable information than the source of unfavorable information, and changed their self-evaluation more toward the favorable than unfavorable position. However, among low self-ideal discrepancy subjects, the change in self-evaluation was accompanied by a similar change in friend evaluation, thereby maintaining their standing in relation to this friend after receiving either positive or negative evaluations. In contrast, high discrepancy subjects downgraded the friend more and upgraded the friend less than themselves, thereby enhancing their relative standing as a result of the feedback. These findings indicated that defensive or self-enhancing effects on self-evaluation processes are determined by self-ideal discrepancy.