A thesis submitted in partial fulfilment of - Queen Margaret University

ascertain if the adult brain can learn new vocabulary following cortical damage
therefore evidence of plasticity in the recovery of language function will now be
presented.
2.5.5 Evidence of plasticity in the recovery of language functions
The adaptability of the brain to recover motor function following neuronal
damage has been presented above (see section 2.5.3). As this investigation is
concerned with the restitution of language function, the evidence regarding the
plasticity of the language areas of the brain will be presented and discussed,
beginning with the ability of the child’s brain to learn language despite the
presence of language impairment. Specific language impairment is a
developmental disorder where children may have difficulty in the recognition,
learning and expression of language, in the presence of normal development in
all other areas. The rehabilitation of phoneme discrimination with these children
in a number of studies found that the repeated auditory stimuli exercises
improved both the recognition and discrimination of the target trained sounds
(Merzenich, Jenkins, Johnston, Schreiner, Miller and Tallal, 1996; Tallal, Miller,
Bedi, Byma, Wang, Nagarajan, Schreiner, Jenkins and Merzenich, 1996). The
authors assert that this training procedure may have caused the plastic
reorganisation of the relevant neurones responsible for temporal segmentation
in these children’s brains. Therefore plastic reorganisation of language function
is evidenced in children but as previously discussed children’s brains are
considered to be more pliable than the adult brain (see section 2.5).
It has been demonstrated that the adult brain can reorganise following neural
damage to the motor and sensory cortex (see section 2.5.3) however, language
is a highly specialised mental function and one that is not readily taken over by
adjoining parts of the brain following damage (Cappa, 2000; Robertson, 1999).
There is however empirical evidence that demonstrates that the adult language
system is receptive to rehabilitation training. An investigation using Positron
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