Beta rhythm

• Frequency: >13 Hz
• Normal in frontal en central area
• Increase of beta due to medication: benzodiazepines, barbiturates and other sedative medications
• Decreased focal beta activity is seen in cortical dysfunction, for instance infarction, abces, tumor, AVM etc.
• Increased focal beta activity could be caused by cortical dysplasia, however sometimes also due to abces, tumor, AVM etc
• Skull defects can cause focal, high amplitude, sharp beta activity (Breach rhythm)