LOCALISED FACE PROCESSING BY THE HUMAN PREFRONTAL CORTEX: STIMULATION-EVOKED HALLUCINATIONS OF FACES

Occasional exceptions to the general trend of null effects in anterior PFC have been reported in isolated case studies.

“Nonetheless, occasional exceptions to this general trend have been reported in isolated case studies (Blanke et al., 2000;Vignal et al., 2000;Vaca et al., 2011;Popa et al., 2016;A. Liu et al., 2020), and the details of effects elicited in the OFC and ACC are also of considerable interest.”

Vignal et al. (2000) reported a patient in whom iES of the right VLPFC consistently caused face-related visual hallucinations across two stimulation sessions.

“In a notable case study, Vignal et al. (2000) reported a patient in whom iES of the right VLPFC (Fig. 4) consistently caused face-related visual hallucinations across two stimulation sessions.”

If the Vignal et al. effect was a perturbation of ongoing perception, then to the authors' knowledge this is the only case of perturbation of ongoing perceptual experience ever reported following iES to the lateral PFC.

“If the latter, then to our knowledge, this is the only case of perturbation of ongoing perceptual experience ever reported following iES to the lateral PFC.”

These studies represent, to the authors' knowledge, the only published reports of iES-elicited effects in lateral PFC regions, not counting motor effects in various frontal motor areas.

“These studies (Blanke et al., 2000;Vignal et al., 2000;Vaca et al., 2011;Popa et al., 2016;A. Liu et al., 2020) represent, to our knowledge, the only published reports of iES-elicited effects in lateral PFC regions (not counting motor effects in various frontal motor areas).”

In the Vignal et al. case, it is not entirely clear whether the effect was a hallucination or a perturbation of ongoing perception.

“Therefore, it is not entirely clear whether this effect was a hallucination or a perturbation of ongoing perception.”