Differential Neuroanatomy of the Gyrus Rectus in Antisocial Disorder with and without Psychopathy: Structural and Functional Correlations using MRI, 99mTc-ECD SPECT, and 18F-SynVesT-1 PET

The gyrus rectus is a core component of the medial orbitofrontal circuit and plays a central role in behavioral inhibition, moral judgment, and impulse control. Alterations in this region have been linked to impulse control disorders, psychopathy, and violent behavior; however, synaptic density in this territory has not been examined in populations with antisocial personality disorder. The aim of this work was to describe structural, functional, and synaptic density differences of the gyrus rectus between individuals with antisocial personality disorder with and without psychopathy. Forty-three individuals with antisocial personality disorder were assessed through psychopsychiatric and neuropsychological examinations, as well as neuroimaging studies (morphometric MRI, 99Tc-ECD SPECT, and 18F-SynVesT-1 PET). Statistical analyses were performed in accordance with current ethical and legal standards. Both groups exhibited significant morphometric and functional alterations. Synaptic reduction was more pronounced in individuals with psychopathy. These findings suggest differential neurobiological patterns of the gyrus rectus, which are relevant for the neuroforensic understanding of inhibitory control and criminal responsibility.