Cognitive mechanisms of volition – the role of cue weighting and sensory integration in health and disease.

Volition is a crucial category in understanding cognitive functioning of humans, and the sense of agency (SoA) can be regarded as its central element. SoA refers to the feeling that I am the cause, the author of given action (and its subsequent effects); it allows to differ between self- and externally-generated events. There are few methods of SoA measurement based on certain perceptual effects which occur only in the case of intentional action: temporal binding, spatial binding, and sensory attenuation. Few models of SoA has been proposed, which stress either the role of sensorimotor prediction in SoA emergence (e.g. comparator model), or rather the role of cognitive inference (e.g. apparent mental causation theory). However, in a more recent cue integration model (e.g. Moore and Fletcher, 2012; Synofzik et al., 2013) these two perspectives are combined. Here, SoA depends on three different types of cues (prior, predictive, and inferential), which are weighted and integrated in a Bayesian manner. Depending on the context, the influence of cues can vary: the higher reliability of the given cue (i.e. the lower its variance), the higher weight it receives and thus the greater influence on resultant SoA it has. This integrative model seems to be well supported by empirical data – not only from the research on regular SoA, but also from numerous cases of anomalous SoA, as present e.g. in schizophrenia. Many details still need further research, however, including the precise range and dynamics of weighting and integration processes (possible asymmetries in weightings depending on the cue type; moderating factors), its specificity in psychotic patients, and the relationship between different SoA measures.

The aim of this project is to address these problems in four lines of research. Current SoA paradigms will be implemented in all experiments, with modifications allowing to test specific predictions of cue integration model. Few methods of experimental manipulations are planned on the level of predictive (e.g. different types of movements), inferential (adding noise to perceptual effects of action), and prior cues (induction of specific causal beliefs). In the first line of research, temporal binding of actions and their affects will be used for SoA assessment; in the second line, it will be analogous effect of spatial binding, and in the third line – sensory attenuation of self-generated action effects. These three lines will be conducted on the healthy subjects, whereas the fourth line will include the samples of individuals with schizophrenia disorder. The results from first three stages will allow to design a paradigm apt to assess specificity of SoA processes as disturbed in schizophrenia. The whole project is thought to contribute to rapidly developing research on volition, agency, and cue integration model of SoA in particular. The results from all stages of the project will be analyzed and presented on both polish and international conferences, as well as published in peer reviewed journals.

Project under supervision of Michał Wierzchoń.