Cortico-thalamo-striatal circuit components’ volumes and their correlations differ significantly among patients with obsessive–compulsive disorder: a case–control MRI study

Abstract

AIM: In the present study, we aimed to determine the volume differences in brain regions involved in cortical-striatal-thalamic-cortical circuit (CSTC) between healthy subjects and obsessive-compulsive disorder (OCD) patients. We also evaluated the potential relationship between volumes of region of interest and various illness parameters (duration and current severity OCD, and the influence of drug treatment). METHODS: We examined the volumetric differences in dorsolateral prefrontal cortex (DPFC), orbitofrontal cortex (OFC), anterior cingulate cortex (ACC), thalamus and striatum between OCD patients (n = 21) and healthy controls (HCs) (n = 25). RESULTS: Patients with OCD had significantly larger total, right, and left DLPFC, and OFC volumes compared to HCs. Total, and left ACC, total, and left striatum volumes were significantly smaller in OCD patients than in HC. The thalamus volumes were not different between two groups. The most of volumetric correlations in HCs disappeared among OCD patients. Only, the correlation between the volumes of left striaum and left ACC volume remained significant. Fisher's r-to-z transformation tests indicated that correlation coefficients of brain volumes significantly differed between both groups for right ACC and left (z = 2.17, p = .03) and right OFC (z = 2.00, p = .04); left ACC and right OFC (z = 2.41, p = .01); right ACC and left (z = 2.94, p = .003), and right striatum (z = 2.43, p = .01). CONCLUSIONS: Our findings indicate the impaired connectivity of ACC, OFC, and striatum in the pathophysiology of OCD. Further research is needed to explore precisely which brain regions nuclei are specifically involved in the occurence of OCD symptoms. ARTICLE HISTORY

Altered Functional Connectivity Strength at Rest in Medication-Free Obsessive-Compulsive Disorder

“…The thalamus is a key region within the CSTC circuit, and thalamic-cortical dysconnectivity has been reported in OCD [36]. Increased gray matter volume and FC in the thalamus have been observed in OCD [8,[37][38][39][40]. Degree values of weighted networks are more resilient to FC disturbances, which are referred to as FC strength [15].…”

Altered spontaneous activity and effective connectivity of the anterior cingulate cortex in obsessive–compulsive disorder

“…In addition to striatal anatomic alterations (Dogan, Ertekin, Turkdogan, Memis, & Sevincok, 2019), there are also reports of decreased volume in the thalamus in OCD (Tang et al, 2016). These observations parallel findings from fMRI studies in OCD that found decreased fractional ALFF (Qiu et al, 2017) and regional homogeneity (Niu et al, 2017) in the thalamus, and decreased ALFF in caudate (Tang et al, 2016), the hypofunction of which were correlated with symptom severity of OCD (Dogan et al, 2019; Qiu et al, 2017). This might lead to the attenuated inhibitory influence of the left thalamus and caudate on left pACC in the present study, but also raises questions about the neurobiological mechanisms for how CSTC circuit alterations might contribute to decreased activity at rest and increased task‐related activation in this structure.…”

“…Dysfunction of caudate is considered a common neural feature of OCD (Graybiel & Rauch, 2000). In addition to striatal anatomic alterations (Dogan, Ertekin, Turkdogan, Memis, & Sevincok, 2019), there are also reports of decreased volume in the thalamus in OCD (Tang et al, 2016). These observations parallel findings from fMRI studies in OCD that found decreased fractional ALFF (Qiu et al, 2017) and regional homogeneity (Niu et al, 2017) in the thalamus, and decreased ALFF in caudate (Tang et al, 2016), the hypofunction of which were correlated with symptom severity of OCD (Dogan et al, 2019; Qiu et al, 2017).…”

“…T A B L E 3 One-sample t tests of normal controls and patients with obsessive compulsive disorder (OCD), respectively, for effects from the whole brain TO the left pregenual anterior cingulate cortex (pACC) In controls, the left pACC exerted a significant excitatory influence on the left thalamus and caudate, and the thalamus and caudate ( Graybiel & Rauch, 2000). In addition to striatal anatomic alterations (Dogan, Ertekin, Turkdogan, Memis, & Sevincok, 2019), there are also reports of decreased volume in the thalamus in OCD (Tang et al, 2016). These observations parallel findings from fMRI studies in OCD that found decreased fractional ALFF (Qiu et al, 2017) and regional homogeneity (Niu et al, 2017) in the thalamus, and decreased ALFF in caudate (Tang et al, 2016), the hypofunction of which were correlated with symptom severity of OCD (Dogan et al, 2019;Qiu et al, 2017).…”

Association of granulocyte macrophage colony-stimulating factor and interleukin-17 levels with obsessive–compulsive disorder: a case–control study findings

“…Although the exact mechanisms are unknown, numerous vital components have been identified. It is considered that a critical role is played by dysfunction in the cortico-striato-thalamo-cortical (CSTC) circuit, which involves communication between the prefrontal cortex, basal ganglia, and thalamus 12 – 14 . Neurotransmitters such as serotonin, dopamine, and glutamate are implicated in OCD pathogenesis 9 .…”