Delayed recognition of emotional facial expressions in Bell's palsy

Abstract

We investigated the impact of acute facial palsy on the recognition of emotional facial expressions. Thirty-one patients with acute facial palsy and 30 healthy controls performed a well-established test battery with tasks both for mere face recognition (FACE) and for recognition of emotional facial expressions (EMO). Participants were tested at disease onset (t1) and about eight weeks thereafter (t2). Recognition accuracy did not differ between groups in FACE and EMO tasks at t1 and t2. By contrast, mean reaction time (RT) in the EMO task was significantly longer for patients than for controls at t1 (10.228 ± 710 ms vs 7.386 ± 283 ms; p = .001), whereas RT in the FACE task did not differ between groups. Parallel to clinical remission, patient's RTs in EMO tasks decreased but remained significantly prolonged at t2. Consistent with theories of embodied cognition, our findings show that facial palsy delays recognition of emotional facial expressions but not face recognition per se. Furthermore, normal accuracy of emotion recognition suggests efficient compensatory mechanisms that preserve this essential social function. We hypothesize that deficient sensorimotor embodiment may contribute to disturbances of non-verbal communication in patients with impaired facial motricity.