RT Book, Section
A1 Shih, Tina
A2 Brust, John C.M.
SR Print(0)
ID 1159966963
T1 Electroencephalography
T2 CURRENT Diagnosis & Treatment: Neurology, 3e
YR 2019
FD 2019
PB McGraw-Hill Education
PP New York, NY
SN 9781259835315
LK neurology.mhmedical.com/content.aspx?aid=1159966963
RD 2024/04/20
AB Electroencephalography  (EEG),  a  diagnostic  test  invented  over  a  century  ago,  is  still  widely  used  today  in  the  evaluation  of  patients  with  paroxysmal  neurologic  disorders  such  as  seizures  and  epilepsy.  Although  brain  electrical  activity  is  very  low  in  voltage  (on  the  order  of  microvolts)  in  comparison  with  ambient  noise  (on  the  order  of  volts),  EEG  uses  the  technique  of  differential  amplification  to  cancel  out  noise  and  increase  the  amplitude  of  the  waveforms  of  interest.  EEG  compares  the  voltages  recorded  from  two  different  brain  regions  and  plots  this  result  over  time.  A  standard  array  of  metal  electrodes  is  placed  on  the  scalp  of  the  patient,  and  over  a  30-minute  period,  brain  electrical  activity  sampled  from  different  regions  of  the  cortex  is  recorded  simultaneously.  EEG  thus  provides  both  spatial  and  temporal  information  about  brain  activity.