Volume 2, Issue 1
1st Quarter, 2007


What it Might "Feel" Like to be Connected to Devices That Will Expand or Enhance Human Function With Cyber Abilities

Lawrence J. Cauller, Ph.D

Page 5 of 8


Image 30 - Induced Visual

One such study has demonstrated the flexibility of brain development by re-routing pathways from the eyes into the auditory system of an embryo which normally receives inputs from the ears and serves the sense of hearing.

Inputs from the eyes make connections with neurons in the auditory system over the course of development and these neurons actually respond to visual inputs like the neurons in visual areas that are the normal target of such inputs from the eyes. Now, this has only been demonstrated in embryos of animals, of course, but the point is that the organization of the young brain is highly malleable.

The brain isn't pre-programmed, it isn’t set up with hard-wired circuits for specific functions, it has evolved with the ability to adapt to normal variations in its inputs, and these studies demonstrate the brain’s capacity for extreme organizational flexibility.  


Image 31 - Clinical Outcomes

It's amazing to realize that a successful treatment for epilepsy involves removing half of the brain, everything on one side, and this has reliably worked in children up to about the age of 15 or so to save them from the devastating effects of epilepsy, surprisingly without causing serious disabilities. In fact, this drastic brain surgery can be successful even in older children, but the treatment causes increasingly more severe deficits at later ages.

Here is a brain scan of a child that has undergone such a procedure showing that the entire left side of the cerebrum has been completely removed. Remarkable, these children grow up without significant cognitive deficits, with IQs comparable to the general population, and can be expected to acquire normal language skills even if the so-called ‘language’ areas were removed.

If they are treated young enough, these children may be left with just a minor loss of strength on the side of their body opposite to the brain surgery. That's how adaptable the brain is, that's the good news, and one needs to keep in mind that without this surgery these kids would probably die or have to be medicated so deeply that they would fail to develop at all. The bad news is that this extreme adaptability of the brain drops off rapidly in adults.

At our age, our brain’s lose their ability to adapt so extremely to epilepsy or other brain diseases.  Such a drastic surgery would certainly paralyze half our body and probably kill us. We can gain some insight into the ability of the adult brain to adapt to major changes by studying the rare cases in which an adult regains a sensory ability that has been damaged for most of their lives. One such intriguing case is that of Mike May who was blind for most of his life, since age 3 when his eyes were severely burned.  


Image 32 - Sendero Group

He re-gained his sight as an adult, when he was about 43 years old, as the result of a revolutionary new treatment that almost completely restored the function of his eyes. Now, his eyes work perfect. His eyes are optically fine and he should have 20/20 vision, but he remains legally blind and can see little better than 20/500.  His doctors believe this limited recovery is because his now mature brain is beyond the developmental point where it can adapt for him to learn to see again.

It is likely that the healthy brain has used that vacated part of the brain to specialize for other functions. He's probably better at other things. He's the CEO of a lucrative company.  I doubt I could become the CEO of such a company. In general, such cases in which sight has been restored relatively late, after spending most of their lives adapted to blindness have been largely disappointing.  
Image 33 - Profound Disappointment

A similar example comes from Oliver Sachs, in his Anthropologist on Mars, [1] where he describes a gentleman who had his eyesight restored as an adult. He had spent most of his life since childhood adapting quite well to blindness and he enjoyed his job as a skilled masseur. But once he could see, he found the sight of naked human flesh repulsive and he had to quit his job. He ultimately slipped into a deep depression and actually preferred to live as a blind person in darkness.  


Image 34 - Intact, Mature Sensory Systems

Despite this apparent failure of the adult brain to regain lost functions, the intact sensory systems of the adult brain has the remarkable ability to adapt to extreme transformations of its normal sensory inputs.  


Image 35 - The world upside down

Classic studies of psychophysics have demonstrated this ability with the aid of inverting lenses which make everything look upside down. Over the course of several days, subjects who continuously wear inverting lenses throughout their daily activities learn to walk naturally, read and write, even ride a bicycle or play tennis.  


Image 36 - Adoptation

The fellow in this figure learned how to ski in an inverted world flipped upside-down.  


Image 37 - Re-adoptation

This guy is jumping off a ramp he’s never worked with before, doing everything just fine. Other senses are just as adaptable; one can learn to hear normally despite shifts in pitch and distorted timbre; similarly, one can identify objects by touch through a long probe like a pencil. As long as sufficient information content is provided, remapping of the intact sensory systems can occur. it's in the software, changes in the strength of the brain’s connections.  


Image 38 - Left-Right Reverse Goggles

These classic experiments have been replicated more recently. Here is a woman with left-right reversing lenses learning to see anew like a baby.

Next Page

Footnote

[1] Anthropologist on Mars – “Neurological patients, Oliver Sacks has written, are travellers to unimaginable lands. An Anthropologist on Mars offers portraits of seven such travellers-- including a surgeon consumed by the compulsive tics of Tourette's Syndrome except when he is operating; an artist who loses all sense of color in a car accident, but finds a new sensibility and creative power in black and white; and an autistic professor who has great difficulty deciphering the simplest social exchange between humans, but has built a career out of her intuitive understanding of animal behavior.”

http://www.oliversacks.com/mars.htm  March 9, 2007 12:57PM EST 

1 2 3 4 5 6 7 8 next page>