Brain rCBF and performance in visual imagery tasks: Common and distinct processes

Understanding the effects of task-specific practice in the brain: Insights from individual-differences analyses

“…The materials were a subset of those used by Kosslyn et al (2004) and Mast, Ganis, Christie, and Kosslyn (2003). To summarize, for the study phase, we prepared 17 simple uppercase block letters and four numbers.…”

“…In contrast, areas for which changes in activation with practice are not related to behavior are assumed, by process of elimination, to implement minimally sufficient processes. In the present study, unlike in Kosslyn et al (2004), we focused on the effects of practice per se-not simply on predicting behavior in individual blocks of trials.…”

“…In the functional magnetic resonance imaging (f MRI) study described here, we used three of the visual imagery tasks employed in the PET study by Kosslyn et al (2004), because these tasks already have some measure of validity. One major advantage of being able to conduct these types of studies with BOLD f MRI is that it allows event-related designs, which permit one easily to eliminate trials associated with an incorrect behavioral response from the analyses, thereby reducing the amount of noise in the results.…”

“…The logic of the approach used in Kosslyn et al's (2004) study relied upon the distinction between minimally sufficient and rate-limiting processes, which presumably are implemented in different brain regions (Kosslyn & Plomin, 2001). A rate-limiting process is a performance bottleneck for a particular task, whereas a minimally sufficient process is not.…”

“…The tasks used by Kosslyn et al (2004) were explicitly designed so that they would rely on distinct rate-limiting processes. In the functional magnetic resonance imaging (f MRI) study described here, we used three of the visual imagery tasks employed in the PET study by Kosslyn et al (2004), because these tasks already have some measure of validity.…”