This document discusses different types of brain waves seen on EEGs, including alpha, beta, theta, and delta waves. It then summarizes several common epilepsy syndromes such as benign centrotemporal lobe epilepsy of childhood, juvenile myoclonic epilepsy, autosomal dominant nocturnal frontal lobe epilepsy, Lennox-Gastaut syndrome, childhood absence epilepsy, and others. It provides examples of EEG findings associated with these conditions, such as Rolandic spikes, generalized spike and wave discharges, and hypsarrhythmic patterns.

1. Recognizing epilepsies Dr. Francois Kouya

3. ALPHA waves Alpha waves are those between 7.5 and thirteen(13) waves per second (Hz). Alpha is usually best seen in the posterior regions of the head on each side, being higher in amplitude on the dominant side. It is brought out by closing the eyes and by relaxation, and abolished by eye opening or alerting by any mechanism (thinking, calculating). It is the major rhythm seen in normal relaxed adults - it is present during most of life especially beyond the thirteenth year when it dominates the resting tracing .

4. BETA waves Beta activity is 'fast' activity. It has a frequency of 14 and greater Hz. It is usually seen on both sides in symmetrical distribution and is most evident frontally. It is accentuated by sedative-hypnotic drugs especially the benzodiazepines and the barbiturates. It may be absent or reduced in areas of cortical damage. It is generally regarded as a normal rhythm. It is the dominant rhythm in patients who are alert or anxious or who have their eyes open

5. Eyes Closed, 14 yrs. old. Very clear beta spindles Frontocentral

6. Eyes Open, 43 yrs. old: Clear frontocentral beta spindles, high-frequency (31-36 Hz).

7. THETA waves Theta activity has a frequency of 3.5 to 7.5 Hz and is classed as "slow" activity. It is abnormal in awake adults but is perfectly normal in children up to 13 years and in sleep. It can be seen as a focal disturbance in focal subcortical lesions It can be seen in generalized distribution in diffuse disorder or metabolic encephalopathy In deep midline disorders or some instances of hydrocephalus

8. DELTA waves Delta activity is 3 Hz or below. It tends to be the highest in amplitude and the slowest waves. It is quite normal and is the dominant rhythm in infants up to one year and in stages 3 and 4 of sleep. It may occur focally with subcortical lesions and in general distribution with diffuse lesions, metabolic encephalopathy hydrocephalus or deep midline lesions. It is usually most prominent frontally in adults (e.g. FIRDA - Frontal Intermittent Rhythmic Delta) and posteriorly in children e.g. OIRDA - Occipital Intermittent Rhythmic Delta).

9. Normal EEG

10. Benign centrotemporal lobe epilepsy of childhood:Benign Rolandic epilepsy Idiopathic localization-related epilepsy that occurs in children between the ages of 3 and 13. Seizures are typically nocturnal and confined to sleep The patients are otherwise normal apart from the seizure

11. Partial or focal EP Benign rolandic epilepsy (BRE)

12. Rolandic spikes and Epilepsy with Continuous spike and waves during slow wave sleep (ECSWS)

13. Juvenile myoclonic epilepsy (JME) Idiopathic generalized epilepsy Generalized tonic-clonic seizures and absence seizures may occur. Associated with sleep deprivation

14. Polyspike and wave discharges seen in juvenile myoclonic epilepsy

16. Autosomal dominant nocturnal frontal lobe epilepsy Idiopathic localization-related epilepsy inherited epileptic that causes seizures during sleep Frontal lobes and consist of complex motor movements, such as hand clenching Arm raising/lowering, and knee bending Shouting, moaning, or crying are also common

17. Frontal lobe EP

18. Autosomal dominant nocturnal frontal lobe epilepsy

19. Juvenile absence epilepsy Idiopathic generalized epilepsy Typically in pre-pubertal adolescence Generalized tonic-colonic seizures can occur

21. EEG of a 53-year-old man with one day history of acute confusion and slowness of motor responses, showing almost continuous generalized spike wave activity.(status epilepticus)

22. Partial or focal EP Benign Rolandic epilepsy (BRE)

23. EEG of an 11-year-old patient, showing rhythmic midtemporal discharges during drowsiness

24. EEG of a 26-year-old patient, showing 6 Hz spike wave paroxysms (phantom spike wave).

25. EEG of a 9-year-old child with benign Rolandic epilepsy, showing a focus of right centrotemporal spike discharges. The right half of the figure shows a spike discharge with horizontal dipole distribution.

26. EEG of a 68-year-old patient with a long history of complex partial seizures, showing a focus of sharp waves and low-amplitude slow activity over the right anterior temporal region

27. Lennox-Gastaut syndrome (LGS) is a generalized epilepsy that consists of a triad of developmental delay or childhood dementia. Mixed generalized seizures Onset occurs between 2-18 years

28. EEG of an 11-year-old patient with Lennox-Gastaut syndrome, showing generalized paroxysmal fast activity (B)

29. EEG of a 16-year-old child with mental retardation and tonic seizures, showing slow spike wave activity superimposed on a slow background .

30. Epilepsies in babies

31. EEG of a 3-day-old comatose neonate with history of seizures, showing an electrographic "alpha band" seizure pattern without clinical accompaniment

32. EEG of a 5-day-old neonate, showing focal ictal pattern characterized by rhythmic sharp waves in the left Rolandic region

33. EEG of a 5-day-old neonate on ventilator, showing "depressed brain seizure" characterized by less than one per second, low-amplitude sharp waves over the right hemisphere.

34. EEG of a 6-month-old infant with developmental delay and infantile spasms, showing typical hypsarrhythmic pattern

36. Childhood absence epilepsy Idiopathic generalized epilepsy that affects children between the ages of 4 and 12 years of age Recurrent absence seizures

37. Typical 3-Hz spike and wave discharges seen in absence epilepsy

38. EEG in Creutzfeldt-Jakob disease

39. Alzheimer's disease (AD) Progressive degenerative brain disease.

40. EEG in Alzheimer's patients

41. Doose Syndrome(also called Epilepsy with Myoclonic-Astatic Seizure or EP with Myo-atonic seizure