Two leading authorities on thalamocortical connections consider how the neural circuits of the brain relate to our actions and perceptions. In this book, two leading authorities on the thalamus and its relationship to cortex build on their earlier findings to arrive at new ways of thinking about how the brain relates to the world, to cognition, and behavior. Based on foundations established earlier in their book Exploring the Thalamus and Its Role in Cortical Function , the authors consider the implications of these ground rules for thalamic inputs, thalamocortical connections, and cortical outputs. The authors argue that functional and structural analyses of pathways connecting thalamus and cortex point beyond these to lower centers and through them to the body and the world. Each cortical area depends on the messages linking it to body and world. These messages relate to the way we act and think; each cortical area receives thalamic inputs and has outputs to motor centers. Sherman and Guillery go on to discuss such topics as the role of branching axons that carry motor instructions as well as copies of these motor instructions for relay to cortex under the control of the thalamic gate. This gate allows the thalamus to control the passage of information on the basis of which cortex relates to the rest of the nervous system.

Examines the two-way relationships between the thalamus and the cerebral cortex; with updated material and a new chapter on the link between perception and action. The thalamus plays a critical role in perceptual processing, but many questions remain about what thalamic activities contribute to sensory and motor functions. In this book, two pioneers in research on the thalamus examine the close two-way relationships between thalamus and cerebral cortex and look at the distinctive functions of the links between the thalamus and the rest of the brain. Countering the dominant "corticocentric" approach to understanding the cerebral cortex—which does not recognize that all neocortical areas receive important inputs from the thalamus and send outputs to lower motor centers—S. Murray Sherman and R.W. Guillery argue for a reappraisal of the way we think about the cortex and its interactions with the rest of the brain. The book defines some of the functional categories critical to understanding thalamic functions, including the distinctions between drivers (pathways that carry messages to the cortex) and modulators (which can change the pattern of transmission) and between first-order and higher-order thalamic relays—the former receiving ascending drivers and the latter receiving cortical drivers. This second edition further develops these distinctions with expanded emphasis throughout the book on the role of the thalamus in cortical function. An important new chapter suggests a structural basis for linking perception and action, supplying supporting evidence for a link often overlooked in current views of perceptual processing.