Prepared by: Roxanne Mae Birador SN
a German psychiatrist (1924)
-published his first paper on the
human electroencephalogram in
-placing needle electrodes under
the scalp of patients who had lost
some of their skull bones in
With Chronic depression, he committed suicide by hanging himself, died at 68y/o
procedure that detects electrical activity of
brain using small, flat metal discs
(electrodes) attached to the scalp
The brain cells communicate via electrical
impulses and are active all the time, even when
the patient is asleep.
16 to 20-25 electrodes are attach to the scalp
The activity of brain shows up as wavy
lines on an EEG recording.
It is a laboratory instrument commonly used to display and
analyze the waveform of electronic signals.
previously called an oscillograph,and informally
known as a scope
FACTORS that may INTERFERE
the reading of EEG:
• Low blood sugar
(hypoglycemia) caused by
• Body or eye movement during
the tests (but this will rarely, if
ever, significantly interfere with
the interpretation of the test)
• Lights, especially bright or
• Certain medications, such as
• Oily hair or the presence of hair
• Drinks containing caffeine, such
as coffee, cola, and tea
(these drinks can occasionally alter
the EEG results, this almost never
interferes significantly with the
interpretation of the test)
TYPES OF ELECTROENCEPHALOGRAPHY
Routine EEG Tests
Wash hair night before or the
day of the test, but don't use
any conditioners, hair creams,
sprays or styling gels.
Hair products can make it
harder for the sticky patches
that hold the electrodes to
adhere to patient’s scalp.
Drugs which may interfere
with the EEG tracing, such
may be withheld for about
24 hours before the test.
Some dietary stimulants, such as tea and
coffee, may also be withheld for 8 to 12
hours before an EEG.
Avoid fasting the night before or the day of
the procedure. Low blood sugar may
influence the results.
If the EEG is to be performed during sleep;
ADULTS may not be allowed to sleep more
than 4 or 5 hours the night before the test
CHILDREN may not be allowed to sleep for
more than 5 to 7 hours the night before.
DURING THE TEST
A technician measures head and marks
scalp with a special pencil, to indicate where to
attach the electrodes.
A technician attaches flat metal discs
(electrodes) to your scalp using a special
adhesive. Sometimes, an elastic cap fitted with
electrodes is used instead.
Once the electrodes are in place, an EEG
typically takes up to 60 minutes. If the patient
need to sleep for the test, it may take up to three
At various times, the technician may ask the patient
to open and close his eyes, perform a few simple
calculations, read a paragraph, look at a picture,
breathe deeply (hyperventilate) for a few minutes,
or look at a flashing light.
Video is frequently recorded during the EEG.
The body motions are captured by a video
camera while the EEG simultaneously records
brain waves. This combined recording may help
the doctor diagnose and treat patient’s