The work is reported in the June 21 issue of Current Biology by a group of researchers including Axel Lindner of the Hertie Institute for Clinical Brain Research and the California Institute of Technology.
In their study, the researchers compared the abilities of healthy individuals and schizophrenia patients to distinguish motion in the external world from motion caused by their own eye movements. In both cases, images pass over the surface of the retina, but the brain normally interprets such images very differently depending on whether the eyes and head are stationary. This interpretation is a specific example of agency attribution. The healthy brain can tell if the movement on the retina is caused by shifting the eyes (in which case image motion is "removed" from perception, and the visual world is experienced as stationary) or if movement on the retina cannot be attributed to shifts in gaze (in which case it is perceived as the actual movement of external objects).
Lindner and colleagues observed a clear correlation between the strength of certain delusions experienced by schizophrenia patients and the amount of "world motion" that these patients perceive while moving their eyes. This correlation supports the view that delusions of influence in schizophrenia may be due to a deficit in a general mechanism that allows healthy individuals to properly attribute agency to sensory experiences.
The researcher include Axel Lindner of the Hertie Institute for Clinical Brain Research, Tübingen, Germany (Present address: California Institute of Technology, Pasadena, California); Peter Thier and Thomas Haarmeier of the Hertie Institute for Clinical Brain Research, Tübingen, Germany; Tilo T.J. Kircher of the University Hospital, Rheinisch-Westfälische Technische Hochschule, Aachen, Germany; and Dirk T. Leube of the University Hospital, Rheinisch-Westfälische Technische Hochschule, Aachen, Germany and University of Tübingen, Tübingen, Germany. This work was supported by the Deutsche Forschungsgemeinschaft and by the Hermann and Lilly Schilling Foundation.
Lindner, A., Thier, P., Kircher, T.T.J., Haarmeier, T., and Leube, D.T. (2005). Disorders of Agency in Schizophrenia Correlate with an Inability to Compensate for the Sensory Consequences of Actions. DOI 10.1016/j.cub.2005.05.049 Publishing in Current Biology, Vol. 15, 1119–1124, June 21, 2005. www.current-biology.com
Journal
Current Biology