<prompt> In EEG the frequency 8-10 hz and amplitude 50-100 pvAlphaBetaThetaDelta  <response>: Alpha: 273Ganong 24th edition; 1015- A.K. Jain 5thMain features of Normal EEG rhythmEEG RhythmFrequency HzAmplitude mVAssociated Features1. Alpha a8-1250-100Present maximally in the occipital and parieto occipital areas when the eyes are closed2. Beta P14-305-10Generally seen in frontal region normal awake pattern commonly seen in infants3. Theta 04-710Often found over the parietal and temporal areas normal in children and in early sleep4. Delta 51 - 4 Lowest20 - 200Usually appears during sleep; can be produced by over breathing or evidence of organic brain disease when seen in awake stateA Gamma rhythm 30 - 80 Hz - often seen when a individual is aroused andfocuses attension on something May be a mechanism to bind together sensory information into a single percept and action This is often replaced by irregular fast activity as the individual initiates motor activity in response to the strimulus Typical spike and rounded waves pattern is characteristic petitmal epilepsy 