Morphometric Differences in Planum Temporale in Schizophrenia and Bipolar Disorder Revealed by Statistical Analysis of Labeled Cortical Depth Maps

Abstract

Differences in cortical thickness in the lateral temporal lobe, including the planum temporale (PT), have been reported in MRI studies of schizophrenia (SCZ) and bipolar disorder (BPD) patients. Most of these studies have used a single-valued global or local measure for thickness. However, additional and complementary information can be obtained by generating labeled cortical distance maps (LCDMs), which are distances of labeled gray matter (GM) voxels from the nearest point on the GM/white matter (WM) (inner) cortical surface. Statistical analyses of pooled and censored LCDM distances reveal subtle differences in PT between SCZ and BPD groups from data generated by Ratnanather et al. (Schizophrenia Research, ). These results confirm that the left planum temporale (LPT) is more sensitive than the right PT in distinguishing between SCZ, BPD, and healthy controls. Also confirmed is a strong gender effect, with a thicker PT seen in males than in females. The differences between groups at smaller distances in the LPT revealed by pooled and censored LCDM analysis suggest that SCZ and BPD have different effects on the cortical mantle close to the GM/WM surface. This is consistent with reported subtle changes in the cortical mantle observed in post-mortem studies.

Cortical thickness in bipolar disorder: a systematic review

“…Ratnanather et al. reported that thickness differences of the left planum temporale could differentiate HC, BD and SZ groups. Hatton et al.…”

“…Six studies reported cortical thinning of the left paracingulate region (BA 32) [ROI: (42); wholebrain: (34,37,40,41,45)]. Six studies reported cortical thinning of the left superior temporal gyrus (BA 22) [ROI: (32,44); whole-brain: (31,34,37,41)]. Some whole-brain studies also reported more widespread cortical thinning across the temporal lobes [including regions of the temporal pole (BA 38) (34, 37), middle temporal gyrus (BA 21) (34,37), and inferior temporal gyrus (BA 20) (34,37,41)].…”

Aberrant Temporal Connectivity in Persons at Clinical High Risk for Psychosis

“…Volumetric reductions of the STG(53) and morphological abnormalities of the planum temporale(54) have long been observed in different phases of the illness, and these same temporal regions have been implicated in the genesis of psychotic symptoms(55). …”

Ventromedial prefrontal cortex thinning in preschool-onset depression

“…Based on this tissue segmentation, the cortical thickness was calculated using Labeled Cortical Distance Mapping (LCDM). LCDM is a well-validated, high resolution approach that has successfully been used to characterize difference in cortical thickness in psychopathology including Alzheimer’s and schizophrenia (Miller et al, 2003; Ratnanather et al, 2013, 2014; Takayanagi et al, 2013; Wang et al, 2007; Karnik-Henry et al, 2012). The LCDM technique characterizes cortical morphometry in terms of the distribution of labeled distances of GM voxels from the grey matter/white matter (GM/WM) surface (Ceyhan et al, 2011, 2013; Miller et al, 2000; Ratnanather et al, 2001).…”