Brain white matter microstructure in deficit and non-deficit subtypes of schizophrenia

Primary and persistent negative symptoms: Concepts, assessments and neurobiological bases

“…An important research question is whether DS represents a more severe form of the same illness with respects to NDS or a separate disease entity. Brain imaging (Gonul et al, 2003;Heckers et al, 1999;Lahti et al, 2001;Tamminga et al, 1992;Vaiva et al, 2002;Quarantelli et al, 2002;Galderisi et al, 2008;Volpe et al, 2012;Voineskos et al, 2013;Mucci et al, 2015a;Spalletta et al, 2015;Wheeler et al, 2015), electrophysiological (Ludewig and Vollenweider, 2002;Bucci et al, 2007;Mucci et al, 2007;Fisher et al, 2012;Li et al, 2013), and oculomotor data (Ross et al, 1996, Hong et al, 2003, showing either less or different abnormalities in patients with DS with respect to those with NDS, suggest that DS represents a separate disease entity with respect to other forms of schizophrenia, and not just the extreme end of a severity continuum. The evidence that DS and NDS have different risk factors (Dollfus et al, 1998;Kirkpatrick et al, 2002Kirkpatrick et al, , 2006Messias et al, 2004;Dickerson et al, 2006;Gallagher et al, 2007;Kallel et al, 2007) and recent taxometric/latent class analyses further support this hypothesis (Blanchard et al, 2005;Ahmed et al, 2015).…”

“…DS patients exhibited disruption of white matter tracts including the inferior longitudinal fasciculus, arcuate fasciculus, and uncinate fasciculus compared to both healthy controls and NDS, suggesting a possible link between these abnormalities and the emotional and social dysfunctions reported in DS patients. Spalletta et al (2015) compared microstructural diffusion-related parameters as measured by diffusion tensor imaging in 21 DS, 21 NDS, and 21 healthy controls. Fractional anisotropy was reduced in the right precentral area in NDS patients, and in the left corona radiata of the schizophrenia group as a whole.…”

Diffusion Imaging of White Matter in Schizophrenia: Progress and Future Directions

“…The simplest approach is to divide patients into symptom-based groups and assess neuroanatomical differences. For example, a number of studies have shown differences between deficit and non-deficit patients, with deficit patients showing either more severe (65, 66) or different (67) WM alterations compared to controls. However, a more sophisticated approach, which relies more heavily on the existence of large data sets, is to take a large group of subjects and use data driven techniques to determine different neurobiological sub-types.…”

Left nucleus accumbens atrophy in deficit schizophrenia: A preliminary study

“…The only study that compared cortical thickness in DSZ and NDSZ found no difference between them (Voineskos et al, 2013). The four DTI studies (Rowland et al, 2009;Kitis et al, 2012;Voineskos et al, 2013;Spalletta et al, 2015) conducted so far found that different associative white matter tracts were more disrupted in DSZ compared to NDSZ; the only partially replicated result was decreased fractional anisotropy in the left uncinate fasciculus of DSZ patients in two of the four studies (Kitis et al, 2012;Voineskos et al, 2013). Unfortunately, none of these findings pertain directly to reward-related regions or circuitries, perhaps with the exception of Delamillieure and colleagues' MRI spectroscopy results that were localized in the medial prefrontal cortex (Delamillieure et al, 2000).…”