Cognitive Science An Introduction to the Science of the Mind

This chapter explores the recent shift in cognitive science toward the brain. The first two sections introduce the rudiments of brain anatomy and then explore Ungerleider and Mishkin's two visual systems hypothesis. Their work provides neural evidence of the two visual pathways (ventral and dorsal routes) in the brain from animal studies. The third section introduces the parallel distributed processing model of cognition introduced by Rumelhart, McClelland, and the PDP group. This model, and what came to be known as artificial neural networks, provide a powerful theoretical explanation of how the brain might process information. The last three sections are focused on early brain imaging studies on cognitive functions. First, Petersen and his colleagues used PET to detect how different brain regions respond to different stages of lexical processing. Next, Brewer and his colleagues localized the brain regions in memory tasks using event-related fMRI. Finally, Logothetis and his colleagues' exploration of the neural correlates of the BOLD signal suggests that fMRI signals could be a function of the input to neural regions rather than of neural firing.