THE PHANTOM LIMB SYNDROME: A
DREAM OR A HALLUCINATION IN BRAIN AREAS DEPRIVED OF SOMATO-SENSORY INPUTS?
By Renato Cocchi,MD
The phantom limb syndrome is a condition in
which the person reports receiving sensations from the lost or amputated limb.
It usually includes pain sensations.
This syndrome is enough common in amputees,
mainly in the early months and years after limb loss.
Besides the pain, the feelings perceived as
deriving from a lost limb, are related to space disposition of the limb itself,
and include warmth, cold, itching. I do not know references to tactile
feelings.
Waiting for the brain has built new
somato-sensory connections between close areas and the area that does not get
more any real perceptions, the phantom limb syndrome remembers the
"hallucinations" during experiments of artificially sensory
deprivation. It remembers even, for analogy, the visual and auditory dreams
during the sleep, which, to see well, is a physiological sensory deprivation
for these two input channels.
We may then think that the brain needs
something for the somato-sensorial reorganization of the brain area deprived of
spatial disposition, thermal and proprioceptive afferent information, over than
painful ones. Waiting for it, the same brain has to maintain stimulated, and
then trophic, the brain area in matter, by sending perceptions taken from the
respective memories.
Posted on Internet on April 2004
Italian translation / Traduzione in italiano