Organization of the Brain

The CNS can be grossly divided into the brain and spinal cord (Fig. 5-1). The brain is subdivided according to anatomic or functional criteria. The following is a brief overview of the general organization of the brain and spinal cord, with some indication of where particular CNS drugs tend to exert their effects. This chapter is not intended to be an extensive review of neuroanatomy—a more elaborate discussion of CNS structure and function can be found in several excellent sources.25 28,40,41... 

Let us now turn to the more philosophical and speculative aspect of this theory of mind. Granted that holography reflects in part the structure and organization of the brain, and granted also that the brain and its structure will in part reflect the nature of the mind arising from it, it follows therefore that the mind itself must in some sense be holographically structured. The questions we must ask then are (1) In what sense is the mind holographically structured, and (2) why should it be so structured ... 

Shepherd GM, Greer CA. 1998. The olfactory bulb. The synaptic organization of the brain. Shepherd GM, editor. New York Oxford UP pp. 159-203. 

Wilson CJ (1998) Basal ganglia. In Shepherd GM (Ed), The Synaptic Organization of the Brain, 4th ed. New York Oxford University Press, pp 329-337. 

CELLULAR ORGANIZATION OF THE BRAIN A PHARMACOLOGICAL VIEW OF NEURONS... 

Other useful texts with greater detail about the nervous system are From Neuron to Brain, by NichoUs, Martin, Wallace, and Kuffler (3rd ed., 1992, Sinauer Assoc., Sunderand Mass.), The Synaptic Organization of the Brain, by Shepherd (4th ed., 1998, Oxford Press, New York), and Fundamental Neuroanatomy, by Nauta and Feirtag (1986, Freeman, New York). 

With regard to tissue blood supply, the organization of the brain and brainstem differs from that of the rest of the body in that there are no anastomoses within the nervous tissue. Each arterial branch is a functional end artery if it were to be occluded, the territory of the brain that it supplied would become hypoxic and ischemic. Because the blood supply to the brain and brainstem is critical for normal cognitive function, a more complete description of the arterial supply follows. 

The alterations in morphological organization of the brain resulting from hypothyroidism have been documented [10-13]. Numerous biochemical parameters are affected by altered thyroid states (for review see 14-16). Recent biochemical data on the effect of thyroid hormones on nerve cell differentiation indicate that they regulate microtubule assembly by changing the concentration and/or the activity of MAPS (tau fraction) [17]. The critical period of effectiveness of thyroid hormones in brain maturation raises a special problem. The correct organization of... 

Less acute deficiencies are responsible for depression, schizophrenia, craving for carbohydrates and sweets, etc. Normal levels cause a balanced personality, while excess is associated with anxiety. The permanent state of anxiety and fearfulness was recently proven to be associated with a hyperactive amygdala (the emotional command organ of the brain) produced by inefficient back-transport of serotonin to its mother cell. 

The great detail of knowledge available on the morphological and functional organization of the brain has been also complemented by ultrastructural studies. These provided strong evidence that the great majority of synapses in the central nervous system of cephalopods are chemical [30]. 

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