Oxytocin-Receptor Gene Modulates Reward-Network Connection and Relationship with Empathy Performance

Dysfunctional striatal-temporal connectivity is associated with a higher risk for violence in patients with schizophrenia

Patients with schizophrenia (SZ) exhibit an elevated risk of violence compared to the general population. However, the neural mechanisms of violence in SZ are still unclear. This study examined the neural correlates linked to violence in SZ and determine whether the brain abnormalities were associated with psychotic symptoms of severe delusions. We performed resting-state functional magnetic resonance imaging and assessed the severity of clinical symptoms and personality traits in 140 male participants, aged 18 to 50 years, comprising 39 violent patients with schizophrenia (VSZ), 45 non-violent patients with schizophrenia (NVSZ), and 56 healthy controls (HC). The results showed increased functional connectivity (FC) in the VSZ group in the right insula - middle frontal gyrus coupling(p < 0.001) and right fusiform gyrus (FFG) - left caudate (CAU) coupling (p < 0.001) as well as decreased FC in the right nucleus accumbens (NAcc) - FFG coupling (p = 0.002), compared to the NVSZ and HC groups. Correlation analysis revealed a negative association between affective deficit and FC of the right NAcc - FFG coupling in the VSZ group only (r = -0.350, p = 0.029). Additionally, suspiciousness correlated negatively with the FC value of the right CAU - left middle temporal gyrus coupling in the VSZ (r = -0.387, p = 0.029) and all-patient groups (r = -0.304, p = 0.023). Our findings suggested that aberrant connections between the cortex and subcortical nuclei, especially the striatal-temporal circuit, might be involved in the neurobiological mechanisms of violence in SZ; at the same time, dysfunction of the CAU might be linked to the disease per se. This study highlighting a specific association between violence and psychopathy rather than symptoms of SZ.

Effects of paternal deprivation on empathetic behavior and the involvement of oxytocin receptors in the anterior cingulate cortex

Paternal deprivation (PD) impairs social cognition and sociality and increases levels of anxiety-like behavior. However, whether PD affects the levels of empathy in offspring and its underlying mechanisms remain unknown. The present study found that PD increased anxiety-like behavior in mandarin voles (Microtus mandarinus), impaired sociality, reduced the ability of emotional contagion, and the level of consolation behavior. Meanwhile, PD reduced OT neurons in the paraventricular nucleus (PVN) in both male and female mandarin voles. PD decreased the level of OT receptor (OTR) mRNA in the anterior cingulate cortex (ACC) of male and female mandarin voles. Besides, OTR overexpression in the ACC reversed the PD-induced changes in anxiety-like behavior, social preference, emotional contagion, and consolation behavior. Interference of OTR expression in the ACC increased levels of anxiety-like behaviors, while it reduced levels of sociality, emotional contagion, and consolation. These results revealed that the OTR in the ACC is involved in the effects of PD on empathetic behaviors, and provide mechanistic insight into how social experiences affect empathetic behaviors.