Hypomotor Seizures in Infants and Children

Research output: Contribution to journalPublished meeting abstract


Hypomotor seizures (characterized by diminished behavioral activity with indeterminate level of consciousness) have been identified as an important seizure type in infants. Our goal was to further investigate the clinical and EEG features of hypomotor seizures.
We retrospectively reviewed 110 hypomotor seizures from 34 patients recorded with video-EEG.
Twenty-seven patients (79%) were less than 48 months of age, while seven (21%) were four to 15 years old. Seventy-one seizures (64%) had regional or lateralized EEG onset, predominately arising from temporal or parietal lobe regions. The other 39 seizures (35%) had generalized onset, usually with diffuse rhythmic slowing or electrodecrement and only rarely (two patients) with slow spike-wave-complexes or three Hertz spike-wave-complexes. Hypomotor seizures with generalized EEG onset were significantly shorter than those with regional or lateralized onset (p= 0.01, GEE model). Unsustained head or eye movements and subtle mouth automatisms were commonly seen in hypomotor seizures with either focal or generalized onset. Seventeen percent of hypomotor seizures with focal onset evolved to include version of head and eyes or jerking of one arm, while two percent of generalized hypomotor seizures evolved to a cluster of spasms.
Hypomotor seizures may be either focal or generalized in nature. Regional EEG onsets were most often temporal or parietal, suggesting that focal hypomotor seizures may be a bland form of [dsquote]complex partial[dsquote] seizures without automatisms, seen predominantly in infants. Generalized hypomotor seizures were rarely associated with an ictal pattern of generalized spike-wave-complexes, suggesting a different mechanism from absence seizures seen later in life.[table]


External organisations
  • Cleveland Clinic Foundation
  • Skåne University Hospital
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Neurology
Original languageEnglish
Pages (from-to)49-49
Issue numberSuppl 42
Publication statusPublished - 2001 Dec
Publication categoryResearch
Externally publishedYes
Event2001 American Epilepsy Society (AES) Annual Meeting - Philadelphia, United States
Duration: 2001 Nov 302001 Dec 5