The role of the brain

This chapter introduces two interpretations of how we know about the world. One, the standard, sensory-to-motor view, is that physical actions for sounds, lights, tastes, smells, and so on act on our sense organs to produce messages that are sent through the nervous system to the cerebral cortex, where the relevant structures of the world can be recognized and appropriate motor actions can be initiated. The other is an interactive sensorimotor view where the nervous system records our interactions with the world, abstracting our knowledge about the world from these interactions. These two opposing views have rarely been considered in terms of specific neural pathways or the messages that they carry; that is the plan for this book. Each view leads to different sets of interpretations of experiments and to different sets of research proposals. The final part of the chapter explores a well-studied and widely taught clinical condition that illustrates the confusions that can arise when the dual meaning of the driver messages to the thalamus is not recognized.