Negative symptoms (NS) represent a core aspect of schizophrenia with a huge impact on real life functioning. Dysfunctions within the dopaminergic cortico-striatal circuits have been documented in subjects with schizophrenia (SCZ) and hypothesized as possible neurobiological mechanisms underlying some domains of NS.

We investigated relationships between the resting-state functional connectivity (RS-FC) of the ventro-tegmental area (VTA) and NS.

Resting-state fMRI data were recorded in 35 SCZ, recruited within the Italian Network for Research on Psychoses. We performed partial correlations between RS-FC and NS (evaluated with the Brief Negative Symptom Scale) controlling for possible sources of secondary negative symptoms.

We found that the experiential domain correlated with the RS-FC of the VTA with the left ventro-lateral prefrontal cortex (lVLPFC) (r=0.372, p=0.039), while the Expressive deficit domain correlated with the RS-FC of the VTA with the left dorso-lateral prefrontal cortex (lDLPFC) (r= 0.470, p .008). Looking at subdomains, only the avolition (r= 0.418, p=0.019) and the blunted affect (r= 0.465, p=.008) showed the same correlations of the domains to which they belong.

According to our findings, separate dysfunctional neuronal circuits could underpin distinct negative symptom subdomains. A better understanding of neurobiological dysfunctions underlying NS could help to design new treatments, targeting different NS subdomains.

Convergent studies provide support for abnormalities in the structure and functioning of the prefrontal cortex (PFC) and the amygdala, the key components of the neural system that subserves emotional processing in major depressive disorder (MDD). We used resting-state functional magnetic resonance imaging (fMRI) to examine potential amygdala–PFC functional connectivity abnormalities in treatment-naive subjects with MDD.

Resting-state fMRI data were acquired from 28 individuals with MDD and 30 healthy control (HC) subjects. Amygdala–PFC functional connectivity was compared between the MDD and HC groups.

Decreased functional connectivity to the left ventral PFC (VPFC) from the left and right amygdala was observed in the MDD group, compared with the HC group (p < 0.05, corrected).

The treatment-naive subjects with MDD showed decreased functional connectivity from the amygdala to the VPFC, especially to the left VPFC. This suggests that these connections may play an important role in the neuropathophysiology of MDD at its onset.