» Articles » PMID: 39217180

Structural and Functional Connectivity in Relation to Executive Functions in Antipsychotic-naïve Patients with First Episode Schizophrenia and Levels of Glutamatergic Metabolites

Abstract

Patients with schizophrenia exhibit structural and functional dysconnectivity but the relationship to the well-documented cognitive impairments is less clear. This study investigates associations between structural and functional connectivity and executive functions in antipsychotic-naïve patients experiencing schizophrenia. Sixty-four patients with schizophrenia and 95 matched controls underwent cognitive testing, diffusion weighted imaging and resting state functional magnetic resonance imaging. In the primary analyses, groupwise interactions between structural connectivity as measured by fixel-based analyses and executive functions were investigated using multivariate linear regression analyses. For significant structural connections, secondary analyses examined whether functional connectivity and associations with executive functions also differed for the two groups. In group comparisons, patients exhibited cognitive impairments across all executive functions compared to controls (p < 0.001), but no group difference were observed in the fixel-based measures. Primary analyses revealed a groupwise interaction between planning abilities and fixel-based measures in the left anterior thalamic radiation (p = 0.004), as well as interactions between cognitive flexibility and fixel-based measures in the isthmus of corpus callosum and cingulum (p = 0.049). Secondary analyses revealed increased functional connectivity between grey matter regions connected by the left anterior thalamic radiation (left thalamus with pars opercularis p = 0.018, and pars orbitalis p = 0.003) in patients compared to controls. Moreover, a groupwise interaction was observed between cognitive flexibility and functional connectivity between contralateral regions connected by the isthmus (precuneus p = 0.028, postcentral p = 0.012), all p-values corrected for multiple comparisons. We conclude that structural and functional connectivity appear to associate with executive functions differently in antipsychotic-naïve patients with schizophrenia compared to controls.

References
1.
van den Heuvel M, Mandl R, Kahn R, Hulshoff Pol H . Functionally linked resting-state networks reflect the underlying structural connectivity architecture of the human brain. Hum Brain Mapp. 2009; 30(10):3127-41. PMC: 6870902. DOI: 10.1002/hbm.20737. View

2.
Andreasen N . A unitary model of schizophrenia: Bleuler's "fragmented phrene" as schizencephaly. Arch Gen Psychiatry. 2003; 56(9):781-7. DOI: 10.1001/archpsyc.56.9.781. View

3.
Manjon J, Coupe P, Concha L, Buades A, Collins D, Robles M . Diffusion weighted image denoising using overcomplete local PCA. PLoS One. 2013; 8(9):e73021. PMC: 3760829. DOI: 10.1371/journal.pone.0073021. View

4.
Waltz J . The neural underpinnings of cognitive flexibility and their disruption in psychotic illness. Neuroscience. 2016; 345:203-217. PMC: 5143214. DOI: 10.1016/j.neuroscience.2016.06.005. View

5.
Voineskos A, Foussias G, Lerch J, Felsky D, Remington G, Rajji T . Neuroimaging evidence for the deficit subtype of schizophrenia. JAMA Psychiatry. 2013; 70(5):472-80. DOI: 10.1001/jamapsychiatry.2013.786. View