ABSTRACT
Research in the last several decades on the organization of the cerebral cortex into separate highly interconnected functional areas and systems has revealed principles that have parallels in thalamic organization. The focus of this chapter will be to highlight aspects of thalamic organization that provide for partially segregated, or parallel processing, within systems, and to explore some hints that thalamic nuclei respect but also may coordinate activity within the well-described cortical hierarchies. The emphasis will be on visual thalamocortical systems in macaque monkeys, as the interconnections and distributed parallel processing are best understood within this model. It should be noted that while the macaque visual thalamus has become one of the better understood models, the hierarchical organization exhibited within this system may not be typical of most others, whose organization may be more strongly parallel. It should be noted that much work on microcircuitry and physiology has been conducted on other thalamocortical systems and species (see Jones, 1985; Sherman and Koch, 1998; McCormick and Huguenard, 1992; Ramcharan et al., 2000). Given the many specializations in the organization of cerebral cortex of different
approach, other systems will be contrasted with the macaque visual thalamocortical model to illustrate the range of different organizational strategies that may exist.
