Giant Brain

Bull. LA. Neurol. Soc. 37: 131, 1972.

A Giant Walk-Through Brain. Bogen, J.E.

Little more than a century ago, the study of neuroanatomy was still the research interest of a few individuals. Even the simplest facts which could give it clinical significance were still in doubt. The investigators of Gall(1) said in 1809 ,of the pyramidal decussation :

"How has it happened that a point of structure so evident (described by Mistichelli and Pourfour du Petit in 1709) should have been doubted by the great Haller, recently denied by very skillful men, and confounded by others, among whom may be reckoned Vicq-d'Azyr himself...?

It is probably owing to the want of a sufficiently clear description, and perhaps, also, because of place of the decussation must be often cut in separating the head from the body.

It will be impossible to be mistaken in it, after the demonstrations of Drs. Gall and Spurzheim."

Within the memory of some now living, the intimate anatomy of the brain has acquired everyday clinical relevance. And we are now on the threshold of a third era in which an acquaintance with brain structure will be essential to an informed consideration of large-scale social issues including impulsive violence in individuals (2) and cultural differences between ethnic groups (3). Those who are experts will not only need to acquire sophistication in exposition, but they will be successful in their efforts only if the public at large is provided an attractive opportunity to become much more familiar with the structure of the brain than it is at present.

What we require is some means of teaching hundreds of thousands of people the elements of neuroanatomy in a very short time. How can this be done? Among even the specialists who read this journal, some difficulty can arise with respect to neuroanatomic relationships. Suppose we ask: "Imagine a line from the amygdala of one side to the habenular nucleus of the other through what structures does this line pass?" Or, "Standing in the aqueduct at the level of the nucleus of Darkschewitsch, what structures would surround you, and what structures would be just beyond those?" Could a reasonably intelligent college student answer such questions, several months after having had only a few hours of instruction" I suspect so, because of the ease with which some analogous questions can be answered. "Imagine a line from the L.A. County Medical Association front door to the center of the auditorium stage-through what structures would it pass?" Or, "Standing in the second floor east-west hallway near the telephone, which structures would surround you and what structures would be just beyond them?"

Within the memory of some now living, the intimate anatomy of the brain has acquired everyday clinical relevance. And we are now on the threshold of a third era in which an acquaintance with brain structure will be essential to an informed consideration of large-scale social issues including impulsive violence in individuals (2) and cultural differences between ethnic groups (3). Those who are experts will not only need to acquire sophistication in exposition, but they will be successful in their efforts only if the public at large is provided an attractive opportunity to become much more familiar with the structure of the brain than it is at present.

What we require is some means of teaching hundreds of thousands of people the elements of neuroanatomy in a very short time. How can this be done? Among even the specialists who read this journal, some difficulty can arise with respect to neuroanatomic relationships. Suppose we ask: "Imagine a line from the amygdala of one side to the habenular nucleus of the other through what structures does this line pass?" Or, "Standing in the aqueduct at the level of the nucleus of Darkschewitsch, what structures would surround you, and what structures would be just beyond those?" Could a reasonably intelligent college student answer such questions, several months after having had only a few hours of instruction" I suspect so, because of the ease with which some analogous questions can be answered. "Imagine a line from the L.A. County Medical Association front door to the center of the auditorium stage-through what structures would it pass?" Or, "Standing in the second floor east-west hallway near the telephone, which structures would surround you and what structures would be just beyond them?"

Within the memory of some now living, the intimate anatomy of the brain has acquired everyday clinical relevance. And we are now on the threshold of a third era in which an acquaintance with brain structure will be essential to an informed consideration of large-scale social issues including impulsive violence in individuals (2) and cultural differences between ethnic groups (3). Those who are experts will not only need to acquire sophistication in exposition, but they will be successful in their efforts only if the public at large is provided an attractive opportunity to become much more familiar with the structure of the brain than it is at present.

What we require is some means of teaching hundreds of thousands of people the elements of neuroanatomy in a very short time. How can this be done? Among even the specialists who read this journal, some difficulty can arise with respect to neuroanatomic relationships. Suppose we ask: "Imagine a line from the amygdala of one side to the habenular nucleus of the other through what structures does this line pass?" Or, "Standing in the aqueduct at the level of the nucleus of Darkschewitsch, what structures would surround you, and what structures would be just beyond those?" Could a reasonably intelligent college student answer such questions, several months after having had only a few hours of instruction" I suspect so, because of the ease with which some analogous questions can be answered. "Imagine a line from the L.A. County Medical Association front door to the center of the auditorium stage-through what structures would it pass?" Or, "Standing in the second floor east-west hallway near the telephone, which structures would surround you and what structures would be just beyond them?"

It is not immediately obvious why topographic learning is so easily acquired and retained by moving about within a structure, although we might suppose that such experience facilitates bi-hemispheric learning, rather than the unihemispheric which is typical of so much academic instruction.

Whatever the reason may be, the message is clear: Neuroanatomy could be taught quickly to large numbers of persons by means of guided tours through a giant brain. The ventricular tour would be instructive and interesting of almost anyone. A tour via one of the large cerebral vessels would conveniently relate brain surface to internal skull features, especially if a handy A/V fistula gave access through the vein of Galen to the sinuses of the posterior fossa. Particularly instructive for those with adequate preparation would be a traverse of the full length of the brain via the pyramidal tract, allowing sufficient time to observe the vast variety of structures visible through transparent walls.

How large would such a brain be? If we allowed two meters headroom for the one millimeter aqueduct, the scale would be 2,000/1. For a six-inch brain including brain stem, we would need 1,000 ft. high building. However, the top 20% could probably be sacrificed, there being little detail of interest within the centrum ovale. Another 10% could be underground, so the above-ground building would be 700 ft. or 60 stories high. If we introduce a little acqueductal dilatation, the scale could be halved. Thirty-story buildings are a commonplace these days, so that construction probably presents no overwhelming obstacle.The cost of the giant brain might well reach eight or perhaps even nine figures. Much larger sums have been, and will be made available, for a variety of undertakings. In favor of this project is the certainty that the major facts adduced will not change in the foreseeable future. And the purpose intended is a goal vital to each of us, a better understanding of our own most important possession.

[This idea was developed in a longer article for the (now defunct) journal Human Nature; it had wonderful illustrations by David Macaulay. Three separate attempts in the past 3 decades to fund this teaching project each got barely off the ground before dying. I still think it is the best idea for teaching neuroanatomy because vision alone without proprioceptive concomitants is much less effective.]