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Abstract:
Abstract: The involvement of the left thalamus in language
function has been demonstrated through the effects of thalamic
lesion and/or stimulation upon language. Recent studies suggested
that the thalamus mainly contributes to bring on line the neural
network supporting language processes. We had the unique
opportunity to observe changes in functional neuro-imaging of
language in a patient who sustained a left thalamic infarct
following the surgery of intractable mesial temporal epilepsy with
left hippocampal sclerosis. Prior to the surgery, the patient who
showed normal verbal abilities performed fMRI studies specifying
the functional mapping for verb generation, reading and auditory
word processing. Following the ablation of the left hippocampus and
polar temporal cortex, she presented with thalamic aphasia. The
fMRI studies repeated one month later showed significant changes in
the neural network implicated in verbal tasks. The comparison with
the post surgical fMRI data of two epileptic patients who underwent
similar left anterior temporal resection helped to specify the
functional changes directly related to the left lateral posterior
thalamic lesion. The findings provide arguments for a direct
involvement of the thalamus in the activation of cortical networks
supporting language functions.
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