LAUSR

A balanced integration of emotional and cognitive information is essential for flexible behaviour, which involves the anterior cingulate cortex (ACC) and the midcingulate cortex (MCC) [1]. Both clinical and preclinical researchers have been interested in studying the role of ACC and MCC in health and disease but preclinical rodent studies so far have suffered from a severe misconception: The definition of ACC/MCC used for rodents is not homologous to the human definition of ACC/MCC. Due to this, numerous findings of rodent studies are not directly translatable to the human situation, an issue that has been addressed in the past [2]. However, the majority of researchers still use the non-homologous definition of rodent ACC/MCC and awareness of the homologous nomenclature needs to be raised. Here, we demonstrate in a series of experiments the value of the homologous rodent ACC/MCC definition for translational research. We conducted a literature review, showing that the non-homologous definition of rodent ACC/MCC does not match human ACC/MCC anatomy and connectivity, while the homologous definition does. We then determined volumes of ACC and MCC in the BALB/cJ mouse, a model demonstrating characteristic symptoms of CD and ADHD (increased aggression and inattention). BALB/cJ mice were tested in the resident-intruder paradigm, demonstrating increased aggression (reduced attack latency: p 0.55 and all p 0.05), highlighting the importance of using the homologous ACC/MCC definition. Last, we aimed to validate our histological findings by using voxel-based morphometry (VBM) of structural magnetic resonance imaging (MRI) data to measure ACC/MCC volumes. BALB/cJ and BALB/cByJ mice were tested in the 5-choice serial reaction time task, a task probing attention. BALB/cJ mice showed a global attention deficit, indicated by an increased percentage of omissions compared to BALB/cByJ mice (p 0.25 and p