Research suggests that perceptual experience of our movements adapts together with movement control when we are the agents of our actions. Is this agency critical for perceptual and motor adaptation? We had participants view cursor feedback during elbow extension–flexion movements when they actively moved their arm, or had their arm passively moved. We probed adaptation of movement perception by having participants report the reversal point of their unseen movement. We probed adaptation of movement control by having them aim to a (...) target. Perception and control of active movement were influenced by both types of exposure, although adaptation was stronger following active exposure. Furthermore, both types of exposure led to a change in the perception of passive movements. Our findings support the notion that perception and control adapt together, and they suggest that some adaptation is due to recalibrated proprioception that arises independently of active engagement with the environment. (shrink)

When interacting with the world, we need to distinguish whether sensory information results from external events or from our own actions. The nervous system most likely draws this distinction by comparing the actual sensory input with an internal prediction about the sensory consequences of one’s actions. However, interacting with the world also requires an evaluation of the outcomes of self-action, e.g. in terms of their affective valence. Here we show that subjects’ perceived pointing direction does not only depend on predictive (...) and sensory signals related to the performed action itself, but also on the affective valence of the action outcome: subjects perceived their movements as directed towards positive and away from negative outcomes. Our findings suggest that the non-conceptual perception of the sensory consequences of self-action builds on both sensorimotor information related directly to self-action and a post hoc evaluation of the affective action outcome. (shrink)

We defend our multifactorial weighting model of the sense of agency and our critique of the comparator model against the critiques that have been brought forward by and . Building on the specification of our model that emerges from this response, we will suggest a distinct mechanism how weighting of different agency factors might work: internal and external agency cues are constantly weighted according to their reliability in a given situation. Thus, the weighting process underlying the sense of agency might (...) follow the principles of optimal cue integration. We review recent empirical evidence for this hypothesis, demonstrating that the multifactorial weighting model is not only testable, but has in fact already received first empirical support. (shrink)

The comparator-model, originally developed to explain motor action, has recently been invoked to explain several aspects of the self. However, in the first place it may not be used to explain a basic self-world distinction because it presupposes one. Our alternative account is based on specific systematic covariation between action and perception. Secondly, the comparator model cannot explain the feeling of ownership of thoughts. We argue—contra Frith and Campbell—that thoughts are not motor processes and therefore cannot be described by the (...) comparator-model. Rather, thoughts can be the triggering cause (intention) for actions. An alternative framework for the explanation of thought insertion in schizophrenics is presented. (shrink)

There is an increasing amount of empirical work investigating the sense of agency, i.e. the registration that we are the initiators of our own actions. Many studies try to relate the sense of agency to an internal feed-forward mechanism, called the ‘‘comparator model’’. In this paper, we draw a sharp distinction between a non-conceptual level of feeling of agency and a conceptual level of judgement of agency. By analyzing recent empirical studies, we show that the comparator model is not able (...) to explain either. Rather, we argue for a two-step account: a multifactorial weighting process of different agency indicators accounts for the feeling of agency, which is, in a second step, further processed by conceptual modules to form an attribution judgement. This new framework is then applied to disruptions of agency in schizophrenia, for which the comparator model also fails. Two further extensions are discussed: We show that the comparator model can neither be extended to account for the sense of ownership (which also has to be differentiated into a feeling and a judgement of ownership) nor for the sense of agency for thoughts. Our framework, however, is able to provide a unified account for the sense of agency for both actions and thoughts. (shrink)

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 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. (shrink)

Sense of agency is a compelling but fragile experience that is augmented or attenuated by internal signals and by external cues. A disruption in SoA may characterise individual symptoms of mental illness such as delusions of control. Indeed, it has been argued that generic SoA disturbances may lie at the heart of delusions and hallucinations that characterise schizophrenia. A clearer understanding of how sensorimotor, perceptual and environmental cues complement, or compete with, each other in engendering SoA may prove valuable in (...) deepening our understanding the agency disruptions that characterise certain focal neurological disorders and mental illnesses. Here we examine the integration of SoA cues in health and illness, describing a simple framework of this integration based on Bayesian principles. We extend this to consider how alterations in cue integration may lead to aberrant experiences of agency. (shrink)

Patients with delusions of control are abnormally aware of the sensory consequences of their actions and have difficulty with on-line corrections of movement. As a result they do not feel in control of their movements. At the same time they are strongly aware of the action being intentional. This leads them to believe that their actions are being controlled by an external agent. In contrast, the normal mark of the self in action is that we have very little experience of (...) it. Most of the time we are not aware of the sensory consequences of our actions or of the various subtle corrections that we make during the course of goal-directed actions. We know that we are agents and that we are successfully causing the world to change. But as actors we move through the world like shadows glimpsed only occasional from the corner of an eye. (shrink)

Over the last 20 years the comparator model for delusions of control has received considerable support in terms of empirical studies. However, the original version clearly needs to be replaced by a model with a much greater degree of sophistication and specificity. Future developments are likely to involve the specification of the role of dopamine in the model and a generalisation of its explanatory power to the whole range of positive symptoms. However, we will still need to explain why symptoms (...) can be so variable and we still do not understand the origin of the most mysterious symptom of all: thought insertion. (shrink)

One oft the most fascinating abilities of humans is the ability to become conscious of the own physical and mental states. In this systematic investigation of self-consciousness, a representational theory is developed that is able to distinguish between different levels of self-consciousness. The most basic levels are already present in such simple animals as ants. From these basic forms, which are also relevant for adult human self-consciousness, high-level self-consciousness including self-knowledge can arise. Thereby, the theory is not only able to (...) integrate developmental considerations but also to sharply distinguish different aspects of the complex phenomenon self-consciousness. Pathological breakdowns of these different aspects, as they can be found in schizophrenia, are explained by specific impairments on different levels of self-representation. In this way, the work shows that a naturalistic theory of self-consciousness is possible, if the analysis starts with very simple and basic mechanisms instead of starting on the »top of the iceberg«. (shrink)