(2006) manipulated the location of object reappearance after object motion had been briefly occluded. Tracking performance was impaired when objects exited the occluder at unexpected locations (e.g., shifted by several object diameters on the vertical axis). Similarly, Graf et al. (2007) modulated the continuity perception of human movement
with another occluder paradigm. Watching short sequences of familiar actions, participants’ task was to detect changes in specific movement parameters after occlusion. Behavioral performance varied as a function of the degree to which occluder length matched the time gap in the occluded movement (both systematically manipulated), Inhibitors,research,lifescience,medical with highest performance for perfect matches. That is, in both studies (Franconeri
Inhibitors,research,lifescience,medical et al. 2006; Graf et al. 2007), the manipulation of spatiotemporal parameters of an observed motion hampered motion perception. The results by Graf et al. (2007) have been taken to demonstrate real-time simulation of observed actions. As a consequence, experimental alterations of the observed actions led to violations of anticipated visuoSKI-606 purchase spatial input. We propose that the findings by Franconeri et al. (2006) were based on similar cognitive processes. Furthermore, Stadler et al. (2011) conducted Inhibitors,research,lifescience,medical a functional magnetic resonance imaging (fMRI) experiment, adopting the Graf occlusion paradigm. The authors compared brain activation elicited by a simulation task to brain activation evoked by cognitive control Inhibitors,research,lifescience,medical tasks, for example, a memory
task. Results suggest significantly more (left hemispheric) dorsal premotor cortex (PMd) activation during the employment of prediction processes in the occluder phase, compared to other cognitive mechanisms (e.g., memory processes). In another behavioral study, Trick et al. (2006) found interferences between MOT and action execution. Subjects performed (1) a standard MOT task, (2) a standard MOT task while additionally performing three-finger tapping sequences, (3) a standard MOT task while additionally articulating three-syllable sequences. MOT performance was significantly more impaired during Inhibitors,research,lifescience,medical additional finger tapping, suggesting that finger tapping and object tracking share cognitive resources and respective neural substrates, possibly the PM. In a meta-analysis, Schubotz and von Cramon (2003) studied activation patterns in the PM during performance of cognitive tasks demanding object-related below attention (e.g., observation and denotation of familiar tools, Grafton et al. 1997), rhythm-related attention (e.g., detection of rhythm violations, Schubotz and von Cramon 2001), and spatial attention (e.g., trajectory predictions of single moving dots, Chaminade et al. 2001). The authors found that spatial attention rather elicited activation in dorsal parts of the PM (PMd), while rhythm and object-related attention rather elicited activation in ventral parts of the PM (PMv).