A thesis submitted in partial fulfilment of - Queen Margaret University

(Kasten and Sabel, 1995) and replicated studies with participants presenting
with visuo-spatial neglect (Mattingley, Robertson and Driver, 1998; Ladavas,
Berti, Ruozzi and Barboni, 1997; Robertson and North, 1992; 1993; 1994;
Robertson, North and Geggie, 1992). This evidence suggests that the damaged
brain is amenable to reorganisation and restoring functional use to impaired
limbs, gait, hemianopia and visuo-spatial neglect following a stroke. However, it
is important to ascertain if this plasticity occurs as a direct result of rehabilitation
or if the brain could recover functions adequately without experience-dependent
rehabilitation.
2.5.4 Does plasticity require therapeutic direction?
As discussed, there is abundant evidence that the adult brain physically adapts
as it acquires and learns new information by making and reforming patterns of
neuronal connections. However before a theory of rehabilitation is developed it
needs to be demonstrated that the recovery of function following brain damage
requires the guidance of experience-dependent rehabilitation, without which it
risks maladapted neurones further causing functional impairment. Some of the
evidence presented above asserts that the provision of specifically targeted
experience was found to produce significantly greater improvement in hand and
finger function than with more generalised exercises alone (Bütefisch et. al,
1995), which is what rehabilitation ultimately aims to provide. There are a
number of studies which suggest the requirement for therapeutic direction to
eliminate or reduce maladaptive neuronal connections.
Evidence of maladaptive connections occurring as a result of acquired deafness
is considered to cause synaptic compensation for decreased sensory input
resulting in false auditory sensations i.e. tinnitus (Jastreboff, 1990). Further
evidence can be found with healthy adults who had a history of normal
development but experienced the development of maladaptive connections as a
result of constant repetition of a particular skill, i.e. focal hand dystonia or
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