We identified 6 semiological signs that reliably distinguish PNES and ES, and found that eyewitness reports of these signs are unreliable. We offer suggestions to improve the accuracy of eyewitness reports.

Low-frequency stimulation of the fornix activates the hippocampus and other areas of the declarative memory circuit. The results of this preliminary study suggest that low-frequency stimulation is tolerable and reduces epileptiform discharges and seizures in patients with intractable mesial temporal lobe epilepsy. A controlled clinical trial may be warranted.

The aim of this study is to investigate functional connectivity between right and left mesial temporal structures using cerebrocerebral evoked potentials. We studied seven patients with drug-resistant focal epilepsy who were explored with stereotactically implanted depth electrodes in bilateral hippocampi. In all patients cerebrocerebral evoked potentials evoked by stimulation of the fornix were evaluated as part of a research project assessing fornix stimulation for control of hippocampal seizures. Stimulation of the fornix elicited responses in the ipsilateral hippocampus in all patients with a mean latency of 4.6 ms (range 2-7 ms). Two patients (29 %) also had contralateral hippocampus responses with a mean latency of 7.5 ms (range 5-12 ms) and without involvement of the contralateral temporal neocortex or amygdala. This study confirms the existence of connections between bilateral mesial temporal structures in some patients and explains seizure discharge spreading between homotopic mesial temporal structures without neocortical involvement.

No abstract

The aim of this study was to investigate functional connectivity between right and left insulae in the human brain. We studied a patient with implanted depth electrodes for epilepsy surgery evaluation with stereotactically placed symmetric depth electrodes in both insulae. Bipolar 1 Hz electrical stimulation of the right and left posterior short gyri in the anterior insula evoked responses in the contralateral insular structures. These responses showed a latency of 8-24 ms. This report demonstrates for the first time bi-directional homotopic and heterotopic functional connectivity between right and left anterior insulae. The short latency of the evoked responses suggests mono- or oligo-synaptic connections, most likely via the corpus callosum.