The aim of the study was to examine the neuropsychological performance and effort in patients with a confirmed PNES diagnosis. The second aim of the study was to investigate the relationship between validity indicators from the cognitive battery with validity and clinical scales from a personality scale. Method: Patients with PNES (N = 250; F:M 186:64; mean age 38.32 (13.23)) were assessed utilizing the RBANS (Czech Research version) to evaluate cognitive performance and to obtain the Effort Index. The MMPI-2 was used to evaluate personality and psychopathology. Results: Global cognitive performance was 0.92 SD below average (according to the Gaussian distribution) in patients with PNES. The lowest scores in the sample were in the Attention domain (À1.7SD). Insufficient effort was detected in 10% of patients. Education correlated negatively with the Effort index (rs = À0.25, p = 0.01). A mild significant correlation in Scale 7 (rs = 0.21, p = 0.01) and Scale 8 (rs = 0.24, p = 0.01), and a significant correlation between Effort Index and Back F Scale (rs = 0.23, p = 0.01) were noted. Conclusions: Assessment of cognitive performance and effort is an essential part of the comprehensive evaluation of patients with PNES during their hospitalization at Epilepsy centers. Many aspects of the neuropsychological assessment can offer useful indications for reaching a differential diagnosis, including clinical history, behavioral observations, cognitive and symptom validity testing, and structured psychological inventories.