Which EEG finding is typical of delirium?

Which EEG finding is typical of delirium?

• A. Alpha waves
• B. Diffuse background slowing
• C. Generalized spike-and-wave
• D. Triphasic waves

Answer: (B)

Delirium is marked by a diffuse slowing of the EEG background, reflecting global brain dysfunction during an acute change in mental status. In this pattern, the normal awake alpha rhythm is reduced and slower theta or delta activity becomes prominent across the cortex. This contrasts with alpha waves, which indicate a normal awake/relaxed state; generalized spike-and-wave discharges, seen in epilepsy; and triphasic waves, which are more typical of metabolic encephalopathy. So the diffuse background slowing best fits the acute delirium pattern.

Delirium is marked by a diffuse slowing of the EEG background, reflecting global brain dysfunction during an acute change in mental status. In this pattern, the normal awake alpha rhythm is reduced and slower theta or delta activity becomes prominent across the cortex. This contrasts with alpha waves, which indicate a normal awake/relaxed state; generalized spike-and-wave discharges, seen in epilepsy; and triphasic waves, which are more typical of metabolic encephalopathy. So the diffuse background slowing best fits the acute delirium pattern.