Shufflebrain

I had performed an even dozen tadamander operations. None of the tadamanders fed, but eight must be discounted because, although they lived for months, they never regained consciousness. I also introduced a number of control operations into the study. In one control series, I evaluated variables of surgery by transplanting the same regions of the brain I had transplanted to produce the tadamander, but with salamanders as donors, instead of tadpoles. These animals regained typical salamander feeding behavior in less than three weeks. What about the possibility that tadpole tissue had some general inhibitory effect on salamander feeding? I controlled this by transplanting various tadpole tissues (brain or muscle or diced tadpole) to salamanders' tail fins or abdominal cavities. These salamanders exhibited no changes in feeding habits. But perhaps frog-brain tissue had an active inhibitory influence on salamander feeding behavior. To test this, I transplanted portions of tadpole brain in place of the salamander's cerebral hemispheres, leaving the rest of the host's brain intact. These animals ate the worms, right out of surgery. Because tadamanders would not eat spontaneously, I had to force-feed each one, which became a major undertaking. Twice a week, I lightly anesthetized each tadamander and inserted fresh salamander muscle into its stomach. Of course, I also had to control the feeding procedure. What if the meal satiated the animal or the anesthetic dulled its appetite? I anesthetized and force-fed normal animals, but neither the anesthetic nor the meal affected their appetites.

The extra work had made Punky the tadamander's season a long one. And I might have terminated the experiment much sooner if I had not grown fond of him.

One morning, I arrived in the lab to find all the active tadamanders except Punky displaying signs of something I had dreaded from the outset--transplant rejection! Fortunately, Punky was still healthy. But I doubted that he would last very long. And I could not risk losing the critical anatomical data inside his cranium.

I stained alternate slides of Punky's tissues in two different ways. One procedure, a widely used all-purpose method known as hematoxylin and eosin, enabled me to judge the overall health of the tissue at the time of preservation. The other method, called Bodian's protargol stain, involved depositing silver salts on very fine nerve fibers, fibers that otherwise do not show up under the microscope. Bodian's stain is tricky. And the moment the technician handed me the slides, I selected one at random merely to check quality. But that very slide had the answer I sought. A cablework of delicate nerve fibers connected the tadpole brain to the salamander medulla. It is irrational, I confess, but I date my belief in hologramic theory from that first look at Punky's brain.

Here is a low-power photomicrograph (40 X on the microscope) of Punky the Tadamander:

***

Here is a picture of Punky's frog brain cells and, immediately below it, cells from his salamander medulla. To the trained eye, the two sets are as different from each other as a cow and a horse.

More Punky, but this time the neural cablework passing between his frog brain and salamander medulla:

The larger oval and round entities are various nuclei. Many of the smaller, grain-like bodies are known as lipofucsin granules; they are indications in general (including human brains) of the onset of degeneration and, I subsequently found, herald brain-graft rejection in this kind of preparation. Not only did Punky's slides tell me that his transplant had established neurological connections with the host parts; they also indicated that I preserved him just in the nick of time. He would have died in a day or so. In fact, if I'd waited just 24 hours more, the nerve fibers might have degenerated beyond microscopic identification.

RETURN TO CONTENTS PAGE

Internet contact:pietsch@indiana.edu

chapter six

The Hologramic Deck