Facial emotion recognition in focal epilepsy: localization is not the main factor.

Objectives: Facial emotion recognition is impaired in people with epilepsy (PWE). Little is known about the factors that truly impact this deficit. Therefore, we aimed to study the role of seizure focus localization, both before and after surgery.

Material And Methods: We retrospectively studied 233 patients with focal epilepsy who underwent presurgical evaluation between 1998 and 2022 at La Pitié Salpêtrière Hospital (Paris, France) and 68 controls. We assessed the impact of epilepsy focus localization, along with demographic, clinical and neuropsychological factors, on presurgical facial emotion recognition and its evolution from pre to post surgery.

Results: PWE performed worse than controls in overall emotion recognition, with a selective impairment in recognizing surprise, disgust, and fear (all p < 0.001). Fear recognition was specifically impaired in medial temporal lobe epilepsy (MTLE, n = 118) and occipito-parietal lobe epilepsy (n = 15) patients, but not in frontal lobe epilepsy (n = 41) or lateral temporal lobe epilepsy (n = 59) patients. Seizure focus localization was not overall a major determinant of emotion recognition performances. Instead, cognitive parameters, mainly intelligence quotient, and the number of antiseizure medications, played a determining role. Surgical resection had no effect on facial emotion recognition deficits, regardless of the resection site.

Conclusion: PWE exhibit lower facial emotion recognition performance; however, neither the localization of the seizure focus nor surgery significantly impacts these deficits, except for fear that was preoperatively selectively impaired in MTLE patients raising out the central role of amygdala in this specific emotion recognition.