• These engage or involve networks on both sides of the brain at the onset
  • There are cases where only one hemisphere involved
• consciousness lost immediately. The level of awareness in the classification is therefore not needed, as all patients lose consciousness
• generalised seizures can be further subdivided into motor (e.g. tonic-clonic) and non-motor (e.g. absence)

specific types include:

• tonic-clonic (grand mal)
• tonic
• clonic
• typical absence (petit mal)
• myoclonic: brief, rapid muscle jerks in a single muscle, one area, or entire body
• atonic

Generalised bilateral tonic-clonic

• No warning of onset
• Symptoms:
  • Tonic phase - whole body stiffness, breathing may stop, loss of bladder control
  • Clonic phase - muscle jerks
• Seizure activity is followed by unconsciousness, muscle relaxation, slow regain of consciousness, confusion, sleepy, headaches and aching limbs. Patients have no recall of episode.

Generalised non-motor typical (absence)

• Rare in adults
• Generally starts between 6-12 years, more common in girls then in boys
• Signs: picked up at school, looks like ‘daydreaming’
  • Patient seems to switch off briefly, cannot be alerted or woken up during this period
• The whole brain involved is involved in this type of seizure, but it has a lower level of activity compared to the classic generalised tonic-clonic seizure.