Functional Anatomy of the Brain

Penfield, W. W. and Jasper, H. Epilepsy and the Functional Anatomy of the Human Brain. Boston, MA Brown, 1954. 

On the left (A) is a profile of the human brain, and on the right, a magnified view (B) of a slice through the brain as indicated by the dotted line. The anatomy of the brain consists of two hemispheres, each covered with multiple layers of important cells known as the cerebral cortex. White matter, which consists of wiring —projections from one cell to another—lies beneath the cerebral cortex, along with some groups of cells that perform various functions. The ventricles are cavities through which runs a substance called cerebrospinal fluid, which helps protect and cushion the delicate structures of the nervous system. 

Tire anatomy of the brain is quite complex, and only a few terms will be defined here. Tire cerebrum, which is made up of two hemispheres, accounts for the largest part of the brain. Tire deeply folded outermost layer, the cerebral cortex, consists of gray matter, a mass of cell bodies, and fine unmyelinated nerve fibers. Beneath this lies a layer of white matter made up of myelin-covered axons connecting the cerebral cortex with other parts of the brain. Tire two cerebral hemispheres are connected by the corpus callosum, a band of 2 x 108 nerve fibers. Remarkably, these fibers can be completely severed with a relatively minimal disruption of the nervous system. In the past the corpus callosum was sometimes cut to control almost incessant epileptic seizures that could not be prevented by drugs. The "split-brain" patients suffered relatively little disability as long as both eyes functioned normally. Studies of these patients provided some insights into the differing functions of the two hemispheres of the cerebrum.395... 

Tamraz, J. and Y. Comair Atlas of Regional Anatomy of the Brain Using MRI With Functional Correlations. Springer-Verlag New York, Inc., New York, NY, 2000 Tycko, U. Nuclear Magnetic Resonance Probes of Molecular Dynamics. Kluwer Academic Publishers, Norwcll, MA, 2003. 

This chapter will discuss the isolation of Drosophila odorant receptor (DOR) genes, how these genes have expanded our understanding of the development and functional anatomy of the olfactory system, how the odor response profiles of OSNs respond to odorants, and the mechanisms by which odor-specific activity is relayed to the brain. 

Scouten CW, Harley CW, Malsbury CW (1982) Labeling knife cuts a new method for revealing the functional anatomy of the CNS demonstrated on the noradrenergic dorsal bundle. Brain Res Bull 8 229-232. 

Parent A, Hazrati L-N (1995) Functional anatomy of the basal ganglia. I. The cortico-basal ganglia-thalamo-cortical loop. Brain Res Rev 20 91-127. 

The structure and function of the human brain have preoccupied physicians and philosophers alike since the dawn of history. Prominent Greek physicians such as Alcmaeon of Groton, Hippocrates, and Galen correcdy considered the nervous system to be the source of sensations, emotions, and cognitive faculties. In the sixteenth and seventeenth centuries, the anatomy of the brain was described in detail by Flemish physician Andreas Vesalius and English physician Thomas Willis. The term neurology was first used by Willis to describe the study of the brain. 

Align the orientation and position of each image and make slight adjustments according to the anatomy of the brain using Translate and Rotate functions under Image. ... 

The analysis of hundreds of lesion experiments conducted mainly on octopuses (review in 28) and of several dozens of serial histological sections of the brains of the animals allowed Young and coworkers to describe the functional anatomy of the nervous system by identifying a circuitry leading to their visual and tactile processing a circuit where learning and memory is achieved by a series of intersecting matrices [2, 22]. 

As we move forward, it will prove helpful to get some basic aspects of the human nervous system in place. An enormous amount of work has gone into making associations between brain anatomy and function. Starting with the three main parts of the brain, we know that the cerebrum is the seat of consciousness. It is divided into two hemispheres, which are linked by the corpus callosum. In a very general sense, the left hemisphere is associated with intellectual and the right hemisphere with emotional responses. Within the cerebrum, one can associate a number of brain areas (the prefrontal, frontal, temporal, parietal, and occipital lobes, for example) with functions including vision and hearing. One can make crude maps in which function is mapped onto brain structure. 

In humans the olfactory receptor cells lie in the mucous membrane at the top of the air passages on either side of the nasal septum. They occupy a total area of about 2 cm, which is small compared with most other mammals. Evidence from both anatomy and embryology shows that the development of the olfactory tissue is closely linked to that of the pituitary gland which lies at the base of the brain. Among other functions the pituitary plays a key role in the coordination of sexual activity and reproduction. This ancient association between the sense of smell and the reproductive process is one that has important implications for work of the perfumer. 

Although there is some modern evidence from neurophysiological research for the anatomical and functional distinctness of these three brains, it is their observable functional qualities that matter for our discussion. I shall continue to use the word brain, but don t be concerned with the anatomy of the physical brain. Gurdjieff used centers at times rather than brain, and also spoke of other centers and finer divisions of these centers, but that level of detail will not concern us here. 

This section reviews basic principles of brain anatomy and function to provide a framework within which to discuss the effect of plants on the CNS. The human nervous system is exceptionally complex, it is the body s major communication system, and is divided into central and peripheral regions. The central nervous system consists of the brain and spinal cord, and the peripheral nervous system consists of all other nerves. Although thought processes and reason are most commonly associated with the CNS, almost every aspect of physiological function is affected by CNS activity. After all, Brain death is widely accepted as the definition of the end of human life 10). The follow description of CNS anatomy and physiology can be foimd in most text books on the and reviews on the subject 11, 17). 

Alajouanine T (1948) Aphasia and artistic realization. Brain 71 229-241 Albin RL, Young AB, Penney JB (1989) The functional anatomy of basal ganglia disorders. Trends Neurosci 12 366-375... 

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