Introduction: Information derived from animal models and neuroradiological studies in humans indicates that mates and females exhibit differences in the functional and anatomical organisation of the brain. This study aimed to evaluate the effect of gender in ictal behaviour considering lateratisation in a group with homogeneous pathology. Methods: Patients with hippocampal seizures who underwent temporal Lobectomy and who were seizure-free during one year of follow-up were selected. Surgery was performed on the right side in 27 patients and on the left side in 21. Videotape recordings of the patients were reviewed in order to investigate ictal behaviour. There were 42 seizure episodes in 20 mates and 40 in 21 females. For auras, 48 patients' data were reviewed. Ictal. behaviour was evaluated taking into consideration the lateratisation of seizures and gender differences. Results: Ictal vocalisation was significantly higher in females with right temporal lobe epilepsy (RTLE) (P < 0.05). Forced head deviation was significantly higher in mates with left temporal lobe epilepsy (LTLE) (P < 0.03) and in females with RTLE (P < 0.0001). Unforced head deviation was significantly higher in mates with RTLE (P < 0.002). Ipsilateral eye deviation was significantly higher in RTLE, with no differences between mates and females. Postictal coughing was significantly higher in RTLE, again with no differences between mates and females (P < 0.03). With regard to automatisms, posturing and nose wiping, there was no difference between right and left temporal lobe seizures or between genders. Conclusions: To the best of our knowledge, this study is the first demonstrating differences in ictal behaviour between females and mates, thus showing that gender is related to different functional and anatomical organisations of the human brain. (C) 2003 BEA Trading Ltd. Published by Elsevier Ltd. At[ rights reserved.