NEUROLOGICAL BASES OF AUTOMATIC AND CONTROLLED PROCESSES

Recent years have witnessed a mounting interest in the impact of the neurological basis of most cognitive processes. Methods such as positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) allow the volumetric variations in regional cerebral blood flow that are related with cognitive activity to be indexed with millimeter-level spatial resolution. Much of the interest on cognitive processes has focused on two phenomena: stimulus-driven or bottom-up effects on attentional selection, and goal-driven or top-down influences. This chapter examines the current status of research on the neurological bases of automatic and controlled processes with reference to fMRI methodologies, to EEG and ERP studies, aiming at clarifying what is known about each of these phenomena and why they are both worth knowing about.