”35 Schizophrenia has long been secondly linked to disruption of frontally mediated PXD101 control systems.37-40 How might the observation of control system disruption and disturbance of the default network be linked? One possibility is that control systems integrate the functions of the default network, which is primarily concerned with internal

modes of cognition, with competing information supplied by networks linked to external attention. The frontoparietal control network,41,42 Inhibitors,research,lifescience,medical illustrated in Figure 3, is anatomically juxtaposed between the default network and networks that contribute to external attention. Dysfunction in psychosis may impact control networks and disrupt coordination between the default network and networks important to processing perceptual information from the external world. Figure Inhibitors,research,lifescience,medical 3. (Opposite) Network dysfunction in psychosis. Brain function and dysfunction

can be examined by exploring how different brain networks interact. The top panel illustrates three networks that include the default network (red), a frontoparietal control network … In a recent study we directly explored the possibility that control system dysfunction may be linked to default network abnormalities by examining interactions between the frontoparietal control network and the default Inhibitors,research,lifescience,medical network43 (Figure 3). Using functional connectivity, 100 healthy control participants were compared with 100 psychotic patients (with schizophrenia, schizoaffective disorder, or bipolar disorder with psychosis). We discovered that functional connectivity

between networks Inhibitors,research,lifescience,medical is different in the patients such that the networks possess less Inhibitors,research,lifescience,medical modular organization. The frontoparietal network, in particular a subnetwork of the frontoparietal network linked to the highest orders of executive control, showed altered coupling to other networks. Suggesting that the differences were a correlate of illness, the patterns linked to psychosis could not be mimicked in control participants, even when the data were degraded by head motion, although it is not possible to fully rule out more subtle confounds. Others have also recently observed network-wide differences in psychosis with Entinostat some features shared between schizophrenia and bipolar disorder and other features unique to schizophrenia.44,45 In a particularly thorough study of a large sample of patients with schizophrenia, altered functional connectivity was found for both the frontoparietal control network and default network.44 It is difficult to decisively interpret these collective results, but it is intriguing that normal network interactions break down in psychotic patients in a manner that might blur the boundary between imagination and reality.