Hess Angelaki
Fakultäten » Medizinische Fakultät » Neurologie, Klinik für » Prof. Dr. Bernhard Hess » Hess Angelaki
Completed research project
| Title / Titel | Mechanisms of spatial orientation in humans | ||||
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| Abstract (PDF, 14 KB) | |||||
| Summary / Zusammenfassung | Whether avoiding obstacles or just drinking a cup of coffee, interacting with the environment remains a basic and essential task. But how do we perceive and manipulate stationary objects in the world when we are constantly on the move? To maintain spatial constancy, we must take into account our every movement when judging the locations of objects relative to ourselves. This perceptual stability is achieved via calculations that require two vital pieces of information: (1) visual information about the location of objects in the environment, and (2) information about self motion (versus object motion). (1) Visual information about the world around us reaches our consciousness via the visual system. Objects reflect light that projects onto our retinas and is then transmitted to the occipital lobe of the cerebral cortex. Once here, various aspects of the objects such as shape, color, texture and motion are processed individually and subsequently bound into our perceptions. It is this final visual representation of space that must be updated each and every time we move. Although the neural mechanisms for spatial constancy have been extensively studied during eye movements (Hallett and Lightstone 1976; Duhamel et al. 1992), little is currently known about head and body movements (i.e., vestibular-driven mechanisms). (2) Information about our movements is derived from several sources. First, sensory inputs are available in the form of vestibular signals from the balance organs of the inner ear including the semicircular canals (which tell us about our rotations in space) and otolith organs (which tell us about our translations in space and how we are oriented relative to gravity). In addition, proprioceptive cues from the muscles and joints as well as somatosensory cues from our skin also provide information about the orientation of our limbs. Finally, copies of our motor output commands (known as efference copies or corollary discharge signals) can also be used to estimate the movements we are about to make. |
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| Publications / Publikationen | Klier EM, Hess BJM, Angelaki DE. Human visuospatial updating after passive translations in three-dimensional space. J Neurophysiol 99: 1799-1809, 2008Klier EM, Angelaki DE, Hess BJM. Human visuospatial updating after noncommutative rotations. J Neurophysiol 98: 537-544, 2007Klier EM, Hess BJM, Angelaki DE. Differences in the accuracy of human visuospatial memory after yaw and roll rotations. J Neurophysiol 95: 2692-2697, 2006Klier EM, Angelaki DE, Hess BJM. Roles of gravitational cues and efference copy signals in the rotational updating of memory saccades. J Neurophysiol 94: 468-478, 2006 Erratum in: J Neurophysiol 98: 558, 2007 |
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| Project leadership and contacts / Projektleitung und Kontakte |
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| Funding source(s) / Unterstützt durch |
Foundation Betty and David Koetser Foundation for Brain Research |
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| In collaboration with / In Zusammenarbeit mit |
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| Duration of Project / Projektdauer | Aug 2003 to Dec 2008 |