Regional increases of cortical thickness in untreated, first-episode major depressive disorder

Abstract

The large majority of structural MRI studies of major depressive disorder (MDD) investigated volumetric changes in chronic medicated patients in whom course of illness and treatment effects may impact anatomic measurements. Further, in few studies, separate measurements of cortical thickness and surface area have been performed that reflect different neurobiological processes regulated by different genetic mechanisms. In the present study, we investigated both cortical thickness and surface area in first-episode, treatment-naïve, mid-life MDD to elucidate the core pathophysiology of this disease and its early impact on the brain. We observed increased cortical thickness in the right hemisphere, including medial orbitofrontal gyrus, pars opercularis, rostral middle frontal gyrus and supramarginal gyrus. Increased thickness of rostral middle frontal gyrus was negatively related with depression severity on the Hamilton Depression Rating Scale. Furthermore, MDD patients showed significantly increased associations in cortical thickness measurements among areas where increased cortical thickness was observed. Analysis of pial area revealed a trend toward increased surface area in the left parahippocampal gyrus in MDD. To permit comparison of our data with those of previous gray matter volume studies, voxel-based morphometry was performed. That analysis revealed significantly increased gray matter volume in left paracentral lobule, left superior frontal gyrus, bilateral cuneus and thalamus which form limbic-cortico–striato–pallido–thalamic loops. These changes in first-episode, treatment-naïve, mid-life MDD patients may reflect an active illness-related cortical change close to illness onset, and thus potentially provide important new insight into the early neurobiology of the disorder.

Precuneal Thickness and Depression in Parkinson Disease

“…Moreover, a direct association between precuneal CT and depression severity has already been demonstrated in non-PD patients with depression [15]. In addition, significant thickening in other cortices, including the frontal, temporoparietal, and cingulate ones, has been demonstrated in non-PD patients with depression [16,17,18]. …”

Electroconvulsive Therapy Modulates the Structural and Functional Architecture of Frontal Pole in Major Depressive Disorder

“…Most previous neuroimaging studies have identified altered GMV [41,42], decreased surface area [43], reduced voxel-mirrored homotopic connectivity [44], and increased fractional amplitude of low-frequency fluctuations [45] in the left CUN in MDD patients. Moreover, the GMV in the CUN was also reported to be associated with better inhibitory control in bipolar depression patients [46].…”

Change in emotional self‐concept following socio‐cognitive training relates to structural plasticity of the prefrontal cortex

“…As described in the introduction, psychopathological conditions such as depression are related to altered self‐referential processing (Nejad et al., 2013) and alterations in the CMS structures (Grimm et al., 2009; Qiu et al., 2014). Specifically, depression is characterized by a heightened focus on the self and a strong identification with negative thoughts and beliefs (Beck, 2008).…”

“…Psychopathological states such as depression are both functionally (Grimm et al., 2009) and structurally (Qiu et al., 2014; Wagner et al., 2012) related to alterations in the CMS structures. The assessment of structural brain change such as cortical thickness has been suggested to be a promising marker for detecting the early onset of diseases (Bruce Fischl & Dale, 2000).…”