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The Brain as Hologram 19 

of a cat's optic nerves can be severed without seriously impairing its
ability to perform complex visual tasks.

Such a situation was tantamount to believingthat a movieaudience 

could still enjoy a motion picture even after 90 percent of the movie 

screen was missing, and his experiments presented once again a seri- 

ous challenge to the standard understanding of how vision works. 

According to the leading theory of the day, there was a one-to-one 

correspondence between the image the eye sees and the way that 

image is represented in the brain. In other words, when we look at a 

square, it was believed the electrical activity in our visual cortex also 

possesses the form of a square (see fig. 5).

Although findings such as Lashley's seemed to deal a deathblow to 

this idea, Pribram was not satisfied. While he was at Yale he devised 

a series of experiments to resolve the matter and spent the next seven 

years carefully measuring the electrical activity in the brains ofmon- 

keys while they performed various visual tasks. He discovered that 

not only did no such one-to-one correspondence exist, but there wasn't 

even a discernible pattern to the sequence in which the electrodes 

fired. He wrote of his findings, "These experimental results are incom- 

patible with a view that a photographic-like image becomes projected

onto the cortical surface."

FIGURE 4. Unlike normal photographs, every portion of a piece of holographic film 
contains all of the information of the whole. Thus if a holographic plate is broken 

into fragments, each piece can still be used to reconstruct the entire image.

Vision Also Is Holographic

Memory is not the only thing the brain may process holographically. 
Another of Lashley's discoveries was that the visual centers of the 

brain were also surprisingly resistant to surgical excision. Even after 

removing as much as 90 percent of a rat's visual cortex (the part of 

the brain that receives and interprets what the eye sees), he found it 
FIGURE 5. Vision theorists once believed there was a one-to-one correspondence 
could still perform tasks requiring complex visual skills. Similarly, 
between an image the eye sees and how that image is represented in the brain. 
research conducted by Pribram revealed that as much as 98 percent
Pribram discovered this is not true.

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