Neuronal firing patterns during the spread of an occipital lobe seizure to the temporal lobes in man.

Neuronal recordings from occipital cortex and hippocampus during a seizure originating in the occipital lobe of a patient with an occipito-temporal tumor demonstrated that the visual aura resulted from neuronal activation of medial peristriate and possibly other occipital lobe neurons while the psychomotor automatisms followed 10-20 sec later and were caused by recruitment of hippocampal neurons bilaterally. This confirmed that the complex seizure symptoms were caused by propagation from an occipital lobe focus. The psychomotor symptoms have not recurred for the 6 months since interruption of occipito-temporal connections; however, the spared medial occipital neurons still produce visual auras.