A loss of the ability to mentally produce or comprehend speech. See also: dysarthria.

Causes:

Head trauma
senile dementia
stroke

Symptoms:

Slurred speech
Inability to speak
Stuttering
Misunderstanding
Confusion
Inability to listen

Tests/Diagnostics: cerebral angiography
CT scan
X-ray
EEG

Treatments/Cures:

None. Has been known to slowly fade away over time. A speech pathologist may be able to help in some cases.