A thesis submitted in partial fulfilment of - Queen Margaret University

1998), tingling, itching or painful sensations (Hunter et al. 2003) even as long as
25 years after the loss of the limb (Sherman, Sherman and Parker, 1984). This
phenomenon indicates that the brain has not fully registered that the limb is no
longer part of the body and continues to feel sensations in that (nonexistent) arm
or leg. Maladaptive cortical reorganisation has also been found to occur in
amputees where the sensory regions from their face and upper arm re-map to
occupy the cortical territory previously held by the now amputated limb (Yang,
Gallen, Ramachandran, Cobb, Schwartz and Bloom, 1994). Functional
deviancies reported by amputees have supported these findings, for example
when their faces were touched with vibration or various temperatures of water
they felt the sensation as if it were on their phantom limb, further indicating
maladaptive connections made by unguided plasticity. Research has
demonstrated that it is possible to reverse these maladaptive connections using
experience-dependent rehabilitation (Ramachandran and Hirstein, 1998). This
phantom limb phenomenon provides fundamental insights into the functional
reorganisation of the human brain (Ramachandran and Hirstein, 1998). That is,
these studies demonstrate that the neuronal connections in the brain can be rerouted
or re-mapped through experience-dependent learning as neural circuits
are trained or even tricked into changing their connection patterns (Robertson,
1999). Additionally, these studies also demonstrate that without such guided
plasticity maladaptive connections may be made reducing the functional ability
of the individual.
In summary, the evidence presented above has demonstrated the ability of the
adult brain to recover function following a stroke and brain-imaging techniques
have identified cortical plasticity in the motor and sensory cortex as a result of
experience-dependent rehabilitation. The importance of rehabilitation has also
been demonstrated in guiding this cortical reorganisation with evidence
indicating that maladaptive neural connections can be made if the brain is left to
recover independent of any structured guidance. This investigation aims to
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