Abstracts

Rationale:
Musicogenic and non-musicogenic auditory seizures both originate in the temporal lobes and involve the auditory cortex, but they have notable differences in triggers, natural history and EEG localization. While audiogenic seizures are triggered by a simple sound stimulus with minimal latency from stimulus to seizure, musicogenic seizures are characterized by more complex auditory stimuli which can be experienced for several minutes before the seizure occurs. Audiogenic epilepsy tends to present in youth, while musicogenic epilepsy tends to present later in life. Audiogenic seizures and focal seizures with auditory component originate from either or both temporal lobes without a clear hemispheric predilection. In contrast, musicogenic seizures seem to predominantly involve the temporal lobes with a right–sided preponderance, and demonstrate rapid involvement of bilateral frontal lobes, insula, and several additional cortical locations.  These findings are derived from scalp EEG studies, fMRI, FDG-PET scan and Ictal SPECT studies; there are no studies that have directly compared intracranial findings between the two reflex epilepsies with auditory components. This case series compares and contrasts the stereotactic EEG (sEEG) findings and natural history of four cases of auditory and/or musicogenic epilepsy.
Method:
Case series and literature review
Results:
Among all patients who underwent sEEG at OHSU, four cases of auditory and/or musicogenic epilepsy were identified: two with musicogenic epilepsy and two with non-musicogenic auditory epilepsy (Table 1 for demographics and detailed EEG findings). Both patients with musicogenic epilepsy were women who developed seizures in childhood, and years later developed music-induced seizures to particular songs and/or types of “emotional” music. Patient 1 had bilateral temporal lobe seizures (mesial temporal + Heschl’s gyrus with early insular spread) on sEEG, but music only triggered right-sided seizures. Patient 2 had exclusively right-sided temporal lobe seizures (mesial temporal + Heschl’s gyrus with early insular spread). The two cases of auditory seizures also originated from the temporal lobe and seizure onset was in early adulthood. Patient 3 had audiogenic seizures with auditory aura, localized to bilateral primary auditory cortex on sEEG . Patient 4 had auditory seizures without any sensitivity to sound as a trigger, and seizures localized to bilateral primary auditory cortex on sEEG.
Conclusion:
This cases series supports the existing literature that musicogenic seizures tend to have a right-sided predominance while auditory seizures appear to have varying laterality. The musicogenic seizures we recorded on sEEG originated nearly simultaneously in the right-sided mesial temporal structures (hippocampus and amygdala) and primary auditory cortex (Heschl’s gyrus), then had early insular propagation. By contrast, auditory seizures originate in the auditory cortex without early mesial temporal involvement, and have varying laterality.
Funding:
:N/A