62 Original article Folia Med. Fac. Med. Univ. Saraeviensis 2016; 51(2): 62-69 foliamedica.mf.unsa.ba Right-left and sex dependent differences of hippocampus and amygdala sizes and their relation to the clinical symptoms of schizophrenia: a comparative brain segmentation study Amani Elfaki 1* , Tahir Osman Ali 2 , Amira Mohamed Osman 3 , Meltem Acar Gudek 1 , Murat Golpinar 1 , Ibrahim Erkan 4 , Bunyamin Sahin 1 1 Department of Anatomy, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey. 2 Department of Anatomy, Faculty of Medicine, National Ribat University, Khartoum, Sudan. 3 Department of Psychiatry, Faculty of Medicine, International University of Africa, Khartoum, Sudan. 4 Department of Biostatistics and Medical Informatics, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey. Submitted: 27.09.2016. / Accepted: 12.12.2016. *Corresponding author Amani Elfaki Department of Anatomy, Faculty of Medicine, Ondokuz Mayis University, Samsun 55139, Turkey. Tel: +90 539 845 10 98 +249 912 223 841 Email: amanielfaki@gmail.com amani.elfaki@omu.edu.tr ABstract Objectives: e hippocampus and amygdala are believed to be central to the cognitive deficits associated with the schizophre- nia. In the current study, the volumes of the hippocampus and amygdala have been examined depending on the right and left sides and sex in patients with schizophrenia and controls. We also evaluated the relation between the quantitative data and their relation to the clinical symptoms of patients. Methods: 82 controls (47 male, 35 female) and 54 schizo- phrenic patients (28 male, 26 female) participated in the study. Structural magnetic resonance images were used to determine hippocampal and amygdala volumes that were automatically obtained using automatic brain segmentation software. Results: e volume of right hippocampus in patients (3.80cm 3 ) was less than controls (4.21cm 3 ), additionally; right hippocampus was less in female patients (p≤0.05). e volume of left hippocampus in patients (3.65cm 3 ) was less than controls (4.05cm 3 ), while no sex difference was found (p>0.050). e volume of right amygdala shows no difference between patients (1.39cm 3 ) and controls (1.50cm 3 ), although it was significant less in female patients (p≤0.05). e volume of the left amyg- dala in patients (1.26cm 3 ) was less than controls (1.42cm 3 ), ad- ditionally; right amygdala was less in female patients (p≤0.05). Conclusions: e present study demonstrates that abnormal volumes of the hippocampus and amygdala were evident in patients with schizophrenia in comparison with the controls. Female patients have hippocampal volume reduction on the right side, In addition to bilateral volume reduction of amygda- la. In this study, patients with schizophrenia displayed marked thought disorder and social withdrawal. Keywords: Schizophrenia, positive symptoms, negative symp- toms, cognitive deficits, magnetic resonance imaging, automat- ic brain segmentation. © 2016 Folia Medica Facultatis Medicinae Universitatis Saraeviensis. All rights reserved. Introduction In latest years, using magnetic resonance imaging (MRI), scientists try to establish suggestions about the role of hippocampus and amygdala in schizophrenia. e hippocampus is known to play a critical role in declarative memory and declarative memory is one of the most consistently impaired functions in schizo- phrenia [1]. So it has been hypothesized that the hip- pocampal volume and shape changes seen in schizo- phrenia may lead to the well-documented memory abnormalities seen in this disorder [2]. Direct emotional responses to information, especially to fear and anxiety, occur in the amygdala, in addition, the amygdala is thought to be involved in emotional memory retention [3]. It is believable that symptoms of schizophrenia such as inappropriate or flattened affect might relate to a change in the structure of the amyg- dala and its connections [4]. Previous studies discovered significant gender-depen- dent differences in patients with schizophrenia. ese differences are believed to be as a result from the effects of sex hormones along with neurodevelopmental and psychosocial sex differences [5]. ere is evidence that female schizophrenia patients display less hippocampal and amygdala size reduction than male schizophrenia patients [6]. Abnormalities of various morphological characteristics and asymmetries of cortical surfaces in schizophrenia have also been shown to be mediated by sex differences [7].