This document discusses how imposing divisions on the nervous system helps understand brain operations and localize diseases, but diseases do not always restrict themselves to these divisions. As a result, neurological diseases can have mixed effects that spread across multiple nervous system divisions. Specifically, mixed dysarthrias represent a heterogeneous group of speech disorders and neurological diseases where any combination of the pure dysarthria types is possible, and several classic neurological disorders like multiple sclerosis can produce multiple types of dysarthria concurrently.

1. GRP 4

2.  Imposing functional and anatomic divisions on the
nervous system helps our attempts to understand the
brain’s operations.
 •It also establishes a framework for localizing and
categorizing nervous system diseases.
 • Unfortunately, no rule of nature obligates neurologic
disease to restrict itself to the division we impose upon
it.

3.  • As a result, the effects of neurologic disease can be
“mixed” and spread across two or more divisions of the
nervous system.
 •Mixed dysarthrias represent a heterogeneous group of
speech disorders and neurologic diseases.
 •Virtually any combination of two or more of the pure
dysarthria types is possible, and in any particular mix
any one of the components may predominate.

4.  Several classic neurological disorders, such as multiple
sclerosis, Wilson's disease, and advanced amyotrophic
lateral sclerosis, produce several variations
of dysarthriaconcurrently, including spastic, flaccid,
ataxic, and hypokinetic and hyperkinetic dysarthrias.

12.  https://www.youtube.com/watch?v=6bbY_yhUmM8