Deafferentation in monkeys: pointing at a target without visual feedback.
Although Meniere's s disease is a fairly capricious condition that is marked by periods of remission and exacerbation, we were able to document that most of the 24 patients we tested experienced statistically significant
deafferentation of vestibular function, as measured by changes in caloric excitability differences (figure 3).
Alterations in sensory inputs, such as cutaneous stimulation,
deafferentation, or pain, can affect the motor system and motor control in various ways [1 -3].
A new approach to control central
deafferentation pain: Spinal intrathecal baclofen.
A new approach demonstrated the benefits on somatosensory sensibility and motor performance of the stroke-affected upper extremity that can arise from a pharmacologically-induced temporary functional
deafferentation (TFD) of the forearm [5-7].
This pain is also referred to as central dysesthesia syndrome, central pain, SCI phantom pain,
deafferentation pain, or below-level neuropathic pain.
This outcome can be explained by a variety of nonexclusive mechanisms, including enhancement of spinal cord nociceptive processing by a decrease of the descending inhibition [6, 7], increases in concentrations of excitatory amino acids (EAAs) [8, 9],
deafferentation hyperexcitability of spinal neurons and/or thalamic neurons [10, 11], increased efficacy of previously ineffective synapses [12, 13], and anatomical alterations in the spinal cord [14, 15].
The contribution of dysfunctional input from the injured cord along with effects of
deafferentation (secondary to the death of spinal projection neurons), sprouting of undamaged fibers, and/or the functional unmasking of nonfunctional local connections could help develop focal generators and/or amplifiers of abnormal discharges in supraspinal structures [3,43,72].
This finding goes in line with previous experimental work showing that short-term upper-limb
deafferentation by regional anesthesia leads to a drop in LLT performance [55].
Afferent influences on brain stem auditory nuclei of the chicken: Time course and specificity of dendritic atrophy following
deafferentation. J Comp Neurol.
Mishkin, "Massive cortical reorganization after sensory
deafferentation in adult macaques," Science, vol.
Some peripheral neural neuropathy, such as
deafferentation or entrapment, results in specific changes of the functionally corresponding cortical area [10-12].
