Further Explorations of Thalamocortical Interactions

Abstract

The thalamus and cerebral cortex function as inseparable partners in shaping the sensory, motor, and cognitive processes that underlie behavior. Neither structure can be fully understood in isolation; their reciprocal interactions define much of brain function. This book introduces the fundamental cellular and circuit mechanisms that mediate thalamocortical communication and then develops a series of new ideas that often challenge conventional views. Central themes include (1) the need for a principled classification of thalamocortical and corticothalamic circuits, (2) the relationship between membrane properties and circuit dynamics, (3) the significance of spike timing in thalamocortical and corticothalamic processing and the mechanisms that modulate it, (4) the organization and functional roles of corticothalamic feedback, (5) the contributions of higher order thalamic nuclei to corticocortical communication and cortical operations, (6) a re-examination of efference copy and the distinction between sensory and motor signals, (7) the influence of attention on thalamocortical dynamics, and (8) the role of higher order thalamus in cognitive control. Throughout the book, the authors emphasize the ways in which evolutionary processes impose principled constraints on neural architecture and function, and how such constraints inform theoretical frameworks for understanding thalamocortical relationships. To encourage readers to think beyond the material and views provided throughout the book, each chapter concludes with a section titled “Some Outstanding Questions,” designed to stimulate creative thinking and inspire future advances in our understanding of thalamocortical interactions.