Language function following anterior temporal lobectomy. The authors report the results of a prospective investigation that evaluated postoperative changes in language function after dominant (29 cases) or nondominant (35 cases) anterior temporal lobectomy for treatment of complex partial seizures. These patients received conservative resection of lateral temporal cortex but aggressive resection of medial temporal cortex. None of the patients underwent functional mapping of cortical language ability. All patients were assessed with a standardized aphasia battery (Multilingual Aphasia Examination) before and 6 months after surgery. Postoperatively, the dominant anterior temporal lobectomy group did not show any significant losses in language function compared to patients who underwent nondominant anterior temporal lobectomy. In addition, the dominant temporal lobectomy group showed significant postoperative improvement in complex receptive language comprehension compared to the nondominant group. These results suggest that patients with complex partial seizures of medial temporal lobe onset can undergo a conservative resection of lateral temporal cortex without language mapping. Such surgery carries little risk to language function and provides an excellent postoperative surgical outcome. 