Background:
Our integrative neuroscience model of first-episode schizophrenia (FES) highlights the lack of coordinated neural activity required for effective processing of salient signals of emotion. Aim of this study was to determine whether altered connectivity of frontolimbic networks underlies impairments in coordinated processing of emotion and associated clinical profile.
Methods:
Functional magnetic resonance imaging (fMRI) scans were acquired in 14 patients with FES and 14 matched healthy control subjects during the pseudorandom presentation of fearful and neutral facial expression stimuli. Faces were presented under both overt (conscious) and covert (nonconscious) conditions shown to engage indirect cortical and direct brainstem pathways to the amygdala, respectively. A random-effects model with the following regions of interest (ROIs) was used: amygdala, brainstem, thalamus, visual cortex and the medial prefrontal cortex (MPFC). Following group comparisons, we used psychophysi-ological interaction analysis to examine coupling of amygdala with other ROIs. We used the effect size of differences in coupling in regression analyses to predict patients' clinical profile assessed with the PANSS.
Results:
Patients with FES showed a differential pattern of amygdala interaction with the nodes of direct and indirect pathways and also with the MPFC compared with controls. A greater impairment in these couplings, particularly during conscious processing of fear faces, predicted a greater severity in the conceptual and behavioural disorganization measured by PANSS.
Conclusion:
These findings indicate that break down in amygdala pathways may affect coordinated neural activity required for effective processing of salient signals of emotion and may lead to a disruption of the usual emotional and cognitive associations such as incongruent affect.
