Shufflebrain

Lashley found that destruction of 20 percent or more of a rat's cerebrum could dim its memory of the maze. And increasing the damage would proportionately decrease the animal's recall. But (and this is the single biggest "but" in the history of brain research!), the critical thing was not where he made the wound but how much of the area he destroyed. Lashley got the same results by destroying the same percentages of different lobes. Anticipating hologramic theory, he even analogized memory to interference patterns.[11] He had borrowed the name of his cardinal principle--equipotentiality--from the embryologist Hans Driesch The term, which I'll expand on shortly, means that engrams, or memory traces, are distributed all over the region.

From chemistry, Lashley borrowed the principle of mass action[12 ]to explain how increased brain damage dulled performance. The less engram the brain had to work with, the dumber the animal seemed.

Equipotentiality and mass action became Lashley trademarks. He and his students and followers produced, reconfirmed, and extended their evidence. More recently, the physiologist, E. Roy John, has developed an extensive new line of evidence to support the principle equipotential distribution of memory.

John and his colleagues, working with cats, perfected electrophysiological methods to monitor the learning brain. Electrical activities in the animal's brain assume the form of waves on the recording device. As an animal learns to distinguish flickering lights of different frequencies, the waves begin to change form; and after the animal has learned, the harmonic features of the waves assume distinctive characteristics, which John and his colleagues take to signify memory. And these same waves--and presumably the memory underlying the animal's reaction--show up throughout widely dispersed regions of the brain.[13]

There is always some extraneous "noise" associated with electronic waves--"blips" that are independent of the main waves. Information theorists call the main waves the signal, and an important aspect of electronic communications is the signal-to-noise ratio. John and his group have found that although the main waves are the same all over the brain, signal-to-noise ratio varies. John believes that variations in signal-to-noise ratio account for specific functions of different regions of the brain and explain why, for example, the occipital lobe works in vision and the temporal lobe works in hearing.

How might a structuralist explain John's research One way is to argue that he really did not tap stored memory but instead tapped communications from long-term to short-term compartments. Another is to assume that the alleged noise is really the memory, and that the signals represent some nonspecific nerve-cell activity. I'm not faulting John's work here, incidentally, but merely giving examples of structuralist explanations of his findings.

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Lashley did not resolve the mind-brain conundrum. His work sharpened its intensity, extended its dimensions, and made a whole generation of psychologists afraid even to think of behavior along physiological lines.

As I mentioned before, Lashley took the term (and the concept of) equipotentiality from Hans Driesch. Driesch espoused equipotentiality because dissociated two- and four-celled frog and salamander embryos don't form half or fractions of animals but whole frogs or salamanders. Driesch's research led him to embrace entelechy, the doctrine of vitalism, or the belief that the first principles of life cannot be found in nonliving matter.

Driesch was a man of the nineteenth century. By the time Lashley came along, biology had fallen madly in love with chemistry and physics, and with the belief that life obeys the laws of Nature generally. Lashley had a thorough background in microbiology and chemistry. True to a twentieth-century scientist's view of things, he resisted vitalism and sought to explain his findings by physical and chemical examples. Yet to me, structuralist and materialist that I was, Lashley's principles seemed like dissembling--a cover-up job! I believed that he engaged in a limp form of metaphysics, disguised to sound like science but lacking the practicing metaphysician's depth and scope. Until my shufflebrain research, I thought Lashley had concocted his doctrines as a verbal means of escape from the powerful vitalistic implications of his position. Lashley's ideas seemed like substations on the way to pure vitalism. The best thing to do was ignore him, which is what I did until hologramic theory emerged.

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As we shall see later on, though, the hologram cannot be strictly equated with equipotentiality. As I said in the first chapter, the hologram concerns that property of waves called phase. Phase makes for equipotentiality (when it is a feature of a hologram at all), not the other way around.