Self Comes to Mind

more specifically when it comes to consciousness—the thalamus serves as a coordinator of cortical activities, a function that depends on the fact that several thalamic nuclei that talk to the cerebral cortex are in turn talked back to and that moment-to-moment recursive loops can be formed. Such thalamic nuclei interconnect parts of the cerebral cortex, distant as well as close. The purpose of the connectivity is not to deliver primary sensory information but instead to interassociate information.
    In this close interplay between thalamus and cortex, the thalamus is likely to facilitate the simultaneous or sequenced activation of spatially separate neural sites, thus bringing them together in coherent patterns. Such activations are responsible for the flow of images in one’s stream of thought, the images that become conscious when they succeed in generating core self pulses. This coordinating role is likely to depend on a back-and-forth between the associative thalamic nuclei and the CDRegions that are, in of themselves, also involved in coordinating cortical activities. The thalamus, in short, both relays critical information to the cerebral cortex and massively interassociates cortical information. The cerebral cortex cannot operate without the thalamus, the two having coevolved and been inseparably joined from early development.
THE CEREBRAL CORTEX
    We finally turn to the current pinnacle of neural evolution, the human cerebral cortex. In interplay with the thalamus and brain stem, the cortex keeps us awake and helps select what we attend to. In interplay with the brain stem and thalamus, the cortex constructs the maps that become mind. In interplay with the brain stem and thalamus, the cortex helps generate the core self. Last, using the records of past activity stored in its vast memory banks, the cerebral cortex constructs our biography, replete with the experience of the physical and social environments we have inhabited. The cortex provides us with an identity and places us at the center of the wondrous, forward-moving spectacle that is our conscious mind. 6
    Assembling the consciousness show is such a cooperative effort that it would be unrealistic to single out any particular partner. We cannot engender the autobiographical aspects of self that so define human consciousness without invoking the exuberant growth of convergence-divergence regions that dominate cortical neuroanatomy and neurophysiology. Autobiography could not arise without the seminal contributions of the brain stem toward the protoself, or without the brain stem’s obligate consorting with the body proper, or without the brain-wide recursive integration brought in by the thalamus.
    But while we need to acknowledge the ensemble work of these major players, it is advisable to resist conceptions that trade the specificity of the contributing parts for an emphasis on functionally indistinct, brain-wide neural operations. In terms of its brain basis, the globalized nature of the conscious mind is undeniable. But we have a chance of finding out more about the relative contributions of brain components to the overall process, thanks to neuroanatomically driven research.
The Anatomical Bottleneck Behind the Conscious Mind
     
    The three main divisions we just outlined and their spatial articulation tell a tale of anatomical disproportions and functional alliances that only an evolutionary perspective can help explain. One does not need to be a neuroanatomist to realize the strange mismatch between the size of the human cerebral cortex and that of the human brain stem.
    In essence, adjusted for body size, the basic design of the human brain stem dates back to reptilian times. But the human cerebral cortex is a different story. The cerebral cortex of mammals has expanded enormously, not merely in size but in architectural design, especially in the primate version.
    Because of its mastery in the role of life regulator, the brain stem has long been the recipient and local processor of the information needed to represent the body and control its life. And as it discharged this ancient and important role, in species whose cerebral cortex was minimal or absent, the brain stem also developed the machinery required for elementary mind processes and even consciousness, via the protoself and core self mechanisms. The brain stem continues to carry out these same functions in humans today. On the other hand, the greater complexity of the cerebral cortex has