Re: How does sensory deprivation work?

Dear Dean,

I think that your observations are quite accurate. The effects of sensory 
deprivation indeed depend on the duration of deprivation. Several studies 
suggest that long periods of sensory deprivation may lead to abnormal 
behaviours. One aspect of relaxation is also to reduce the amount of 
sensory input during a period of time. One important aspect of sensory 
deprivation that is better known concern the age at which deprivation 
occurs. Sensory input is crucial for a sensory system to develop normally. 
Several studies have investigated the effect of early monocular 
deprivation (i.e. deprivation of visual input in one eye) on the 
development of the visual system. It is clear that during a critical 
(or “sensitive”) period, monocular deprivation lead to irreversible visual 
deficits such as amblyopia (loss of visual acuity) for the deprived eye. 
Moreover, it leads to abnormal anatomical changes in the visual brain 
structures. One interesting fact is that the deficit is due to an abnormal 
development in the higher visual centres of the brain, not in the eye 
itself. That’s why lenses or anything cannot correct it. During 
development, the visual parts of the brain that received input from both 
eyes need to received those input, otherwise a single input will “invade” 
all the visual structure and after a certain period, the system cannot be 
greatly be changed. So, its like there are no more place for the deprived 
input. This has major implications for future works in the medical domain. 

Eric