Language networks under brain pathological states
The word
networks analysed here allow to explore different questions relating
brain function and language dynamics. A very interesting point here is
the possibility of extracting relevant information concerning the
presence of diseased brain. This actually provides the counterpart of
analysing children development: brain diseases associated with loss of
connections or neurons can have an impact on the structure of language
networks, perhaps providing new ways of understanding how words in the
wordweb are lost as a consequence of neural changes.
FIGURE: degenerative diseases, such Alzheimer's
or multiple sclerosis can be explored anatomically by looking at
postmortem brains and brain scans.
The two figures show the corresponding
anatomical view of a normal (left) and diseased (right) brains,
respectively.
One of the
scenarios explored here involves the analysis of language networks
obtained from patients of Multiple Sclerosis (MS). MS is an
inflammatory disease of the Central Nervous System. It affects
predominantly white matter tissue: nerve fibres which are responsible
for transmitting communication signals both internally within the CNS
and between the CNS and the nerves supplying rest of the body.
In people affected by MS, patches of damage called plaques or lesions
appear in seemingly random areas of the CNS white matter. At the site
of a lesion, a nerve insulating material, called myelin, is lost. It is
a diffuse damage affecting wide areas. Patients display both lexical
and (specially) syntactic disorders associated with the loss of neural
connections.
The networks reconstructed from our method might help gaining
understanding on the tempo and mode of MS progression affecting
language architecture. This work will be done in collaboration with
researchers of the
MULTIPLE SCLEROSIS CENTER at the Universidad de Navarra.
