Intrusive thoughts elicited by direct electrical stimulation during stereo-electroencephalography

Cortical direct electrical stimulation (DES) is a method of brain mapping used during invasive presurgical evaluation of patients with intractable epilepsy. Intellectual auras like intrusive thoughts, also known as forced thinking (FT), have been reported during frontal seizures. However there are few reports on FT obtained during DES in frontal cortex. We report three cases in which we obtained intrusive thoughts while stimulating the dorsolateral prefrontal cortex and the white matter in the prefrontal region. In order to highlight the effective connectivity that might explain this clinical response, we have analyzed cortico-cortical potentials evoked by single pulse electrical stimulation

Intrusive Thoughts Elicited by Direct Electrical Stimulation during Stereo-Electroencephalography

Cortical direct electrical stimulation (DES) is a method of brain mapping used during invasive presurgical evaluation of patients with intractable epilepsy. Intellectual auras like intrusive thoughts, also known as forced thinking (FT), have been reported during frontal seizures. However, there are few reports on FT obtained during DES in frontal cortex. We report three cases in which we obtained intrusive thoughts while stimulating the dorsolateral prefrontal cortex and the white matter in the prefrontal region. In order to highlight the effective connectivity that might explain this clinical response, we have analyzed cortico-cortical potentials evoked by single pulse electrical stimulation

Modular Signatures and Neural Avalanches in Epileptic Brain Networks

Epileptic seizures are characterized by a rich dynamic spectrum consisting of excessive, abnormal and synchronized firing of neuron ensembles. Such abnormal firing has been quantitatively characterized via power laws in neural avalanches. The term “neural avalanche” has been used to illustrate the excessively amplified neural firing patterns that lead to epileptic seizures. The pattern of amplified firing in neural avalanches betrays a modular signature in the spread of activation across cortical minicolumns. According to this modular approach of epilepsy, the excessive amplification of neural firing in a cortical minicolumn results from a defect within the “inhibitory curtain” surrounding the pyramidal cells. The functional basis of this approach provides insights into potential clinical interventions