Abstract
This chapter reviews quantitative neuromorphological investigations of primate neocortex. In particular, we explore regional variation in the basilar dendritic and spine systems of pyramidal neurons. This synthesis indicates a relatively consistent, stepwise increase in dendritic extent and spine number in a caudal-rostral direction. Cortical regions involved in the early stages (e.g., primary sensory areas) of processing generally exhibit less complex dendritic/spine systems than those regions involved in the latter stages of information processing (e.g., prefrontal cortex). This dendritic progression appears to reflect significant differences in the nature of cortical processing, with spine-dense neurons at hierarchically higher association levels integrating a broader range of synaptic input than those at lower cortical levels. In concluding the chapter, we consider the characteristics of the receptive dendritic membrane of individual neuronal elements (e.g., voltage-gated channels, input resistance, voltage attenuation) and how such factors may relate to cortical computation.