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Classical migraine: symptoms between visual aura and headache onset.
1National Hospital for Neurology and Neurosurgery, Queen Square, London, UK.
Lancet (London, England)
|August 8, 1992
Summary
The migraine free interval, the time between visual aura and headache, often includes mood changes and cognitive disturbances, not just feeling normal. These symptoms suggest a widespread brain process rather than a localized vascular event.
Area of Science:
- Neurology
- Neuroscience
- Cerebral Physiology
Background:
- Classical migraine is characterized by visual aura preceding headache.
- The "free interval" is the period between the visual aura's end and headache onset.
- The nature of symptoms during this free interval is not fully understood.
Purpose of the Study:
- To investigate the subjective experiences of patients during the free interval in classical migraine.
- To characterize the symptoms and duration of the free interval.
- To explore potential underlying mechanisms of the free interval.
Main Methods:
- Retrospective study involving twenty-five migraine patients who reported a free interval.
- Patients were interviewed about their experiences during the free interval.
- Data on symptom types and duration were collected.
Main Results:
- Only 3 out of 25 patients felt normal during the free interval.
- 22 patients reported mood alterations, detachment, fears, speech/thought disturbances, or somatic symptoms.
- The interval lasted under an hour for 17 patients, and 1-5 hours for 5 patients.
Conclusions:
- The free interval is often accompanied by significant neurological and psychological symptoms.
- These symptoms suggest involvement of frontal/temporal cortices and hypothalamus.
- Findings support a diffuse cerebral process, not spreading depression or vascular mechanisms.
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