Intraoperative cortical stimulation of the inner part of the posterior superior temporal gyrus reliably induced fear and progressive screaming behavior. Interestingly, stimulation through subdural grid electrodes did not induce this phenomenon. Systematic review of the literature identified fear induction by stimulation of different widespread cortical areas including the temporal pole, the Insula and the anterior cingulated cortex. The posterior part of the superior temporal gyrus has so far not been associated with fear induction after electrical stimulation.
This observation suggests that this area of the brain can be part of a network involved in the elicitation of fear, dysfunction of this network induced by epilepsy could also explain the observed phenomenon. Electrophysiological and imaging studies have to be conducted to improve our understanding of the cortical networks forming the neuroanatomical substrate of higher brain functions and experiences such as fear 1).
The bone flap has been removed and the dura mater has been opened as a flap pediculated towards the greater sphenoid wing previously roungered to improve parasellar visualization. Sylvian fissure, Inferior frontal gyrus, Superior temporal gyrus and Middle temporal gyrus are exposed. Three pars of parasylvian inferior frontal gyrus must be distinguished: pars orbitalis (pOr) in relation to the orbital roof; pars triangularis (pT) the widest area of sylvian fissure (good place for start opening of sylvian fissure); pars opercularis (pOp) where Broca’s Area is located.