Electroencephalography (EEG) is one of
the principle investigative tools of cerebral function.
It is widely accepted as a valuable test in many
conditions. Two familiar basic EEG findings are
slow activity and epileptiform activity. Slow
activity is a nonspecific finding that indicates
dysfunction of the underlying white matter, with
or without gray matter involvement. Focal slow
activity indicates a focal area of cortical dysfunction
which is usually caused by a focal structural lesion
(tumor, stroke, trauma, etc.), although a lesion is
not always found. Diffuse abnormalities on EEG
suggests a diffuse brain degeneration or encephalopathy.
Epileptic or seizure activity which is seen
as spike or sharp wave forms indicates potential
for epileptic seizures. EEG technologists may use
activation procedures such as hyperventilation
and photic stimulation to enhance the ability of
EEG to detect epileptic activity1,2. Research has
consistently demonstrated the benefit of EEG
in distinguishing dementia from disorders such
as metabolic encephalopathy. EEG may also be
useful in distinguishing dementia from depression
– related pseudodementia. EEG has an important
role in distinguishing possible psychotic episodes
and acute confusional state from complex partial
seizures and non-convulsive status epilepticus3-,5,
and has more commonly than its role in diagnosing
or distinguishing between psychiatric disorders
and behavioral abnormalities,