Loss of vision due to injury to the eyes results in deafferentation of very
large areas of the human cortex and poses striking demands on other sensor
y systems to adjust to blindness in a society that heavily relies on vision
. Blind subjects need to extract crucial spatial information from touch and
hearing. To accomplish this, plastic trans-modal changes appear to take pl
ace by which a larger area of the sensorimotor cortex is devoted to the rep
resentation of the reading finger in Braille readers, and parts of the form
er visual cortex are recruited for the processing of tactile and auditory i
nformation.
These findings provide evidence of trans-modal sensory plasticity in humans
. Similar mechanisms might be involved in other forms of skill learning and
recovery from lesions. Recent studies suggest the possibility that availab
le neurophysiologic techniques might not only be used to reveal such plasti
c changes, but may also have a potential role in guiding the plastic change
s, thus improving functional outcome.