Planum temporale asymmetry and thought disorder in schizophrenia

Voglmaier

et al. 1999

Biological Psychiatry

123

Background-Structural MRI data indicate schizophrenics have reduced left-sided temporal lobe gray matter volumes, especially in the superior temporal gyrus (STG) and medial temporal lobe. Our data further suggest a specificity to schizophrenia spectrum disorders of STG volume reduction. Interpretation of research studies involving schizophrenics may be complicated by the effects of exposure to neuroleptics and chronic illness. Sharing the same genetic diathesis of schizophrenics, subjects with schizotypal personality disorder (SPD) offer a unique opportunity to evaluate commonalities between schizophrenia and SPD, particularly as SPD subjects are characterized by cognitive and perceptual distortions, an inability to tolerate close friendships, and odd behavior, but they are not psychotic and so have generally not been prescribed neuroleptics nor hospitalized. Evaluation of brain structure in SPD may thus offer insight into the "endophenotype" common to both disorders. In addition, differences between groups may suggest which are the brain structures of schizophrenics that contribute to the development of psychosis.

Section: Discussionsupporting

confidence: 92%

Schizotypal personality disorder and MRI abnormalities of temporal lobe gray matter

Dickey

Voglmaier

et al. 1999

Biological Psychiatry

123

“…Reduced cortical PT volume was reported in a postmortem study in schizophrenia compared with controls, 18 and we reported reduced left PT gray matter volume and a reversal of PT asymmetry in patients diagnosed as having chronic schizophrenia. 6 Other investigators 7,8 measuring PT area in schizophrenia also reported a reversal of the left larger than right PT asymmetry found in controls. However, several investigators [9][10][11][12][13] have not reported abnormalities of PT asymmetry in schizophrenia.…”

mentioning

confidence: 89%

“…[1][2][3][4][5] Several studies have reported abnormalities in portions of the superior temporal gyrus (STG) in patients diagnosed as having schizophrenia, [1][2][3] including planum temporale (PT) and Heschl gyrus (HG) (primary auditory cortex). [6][7][8][9][10][11][12][13][14] The impetus for much of this work is based on the role that the left (dominant) hemisphere PT plays in language processing [15][16][17] and the role that the HG plays in the initial processing of auditory information. [1][2][3] DeLisi et al 10 measured length of the sylvian fissure and reported asymmetry differences in patients with first-episode schizophrenia compared with controls.…”

mentioning

confidence: 99%

Planum Temporale and Heschl Gyrus Volume Reduction in Schizophrenia: A Magnetic Resonance Imaging Study of First-Episode Patients

Hirayasu

Archives of General Psychiatry

Salisbury

et al. 2000

247

168

Background-Magnetic resonance imaging studies in schizophrenia have revealed abnormalities in temporal lobe structures, including the superior temporal gyrus. More specifically, abnormalities have been reported in the posterior superior temporal gyrus, which includes the Heschl gyrus and planum temporale, the latter being an important substrate for language. However, the specificity of the Heschl gyrus and planum temporale structural abnormalities to schizophrenia vs affective psychosis, and the possible confounding roles of chronic morbidity and neuroleptic treatment, remain unclear.

“…) Additionally, planum temporale asymmetry, an important biological substrate of language, is established during neural development and it, too, has been shown to be abnormal in schizophrenia, again suggesting the importance of neurodevelopmental influences in the etiology of schizophrenia (e.g. DeLisi et al, 1994;Rossi et al, 1994a, 1997Petty et al, 1995;Kwon et al, 1999).…”

Section: Introductionmentioning

confidence: 99%

Amygdala–hippocampal shape differences in schizophrenia: the application of 3D shape models to volumetric MR data

Shenton

Gerig

Psychiatry Research: Neuroimaging

et al. 2002

125

Evidence suggests that some structural brain abnormalities in schizophrenia are neurodevelopmental in origin. There is also growing evidence to suggest that shape deformations in brain structure may reflect abnormalities in neurodevelopment. While many magnetic resonance (MR) imaging studies have investigated brain area and volume measures in schizophrenia, fewer have focused on shape deformations. In this MR study we used a 3D shape representation technique, based on spherical harmonic functions, to analyze left and right amygdala-hippocampus shapes in each of 15 patients with schizophrenia and 15 healthy controls matched for age, gender, handedness and parental socioeconomic status. Left/right asymmetry was also measured for both shape and volume differences. Additionally, shape and volume measurements were combined in a composite analysis. There were no differences between groups in overall volume or shape. Left/right amygdalahippocampal asymmetry, however, was significantly larger in patients than controls for both relative volume and shape. The local brain regions responsible for the left/right asymmetry differences in patients with schizophrenia were in the tail of the hippocampus (including both the inferior aspect adjacent to parahippocampal gyrus and the superior aspect adjacent to the lateral geniculate nucleus and more anteriorly to the cerebral peduncles) and in portions of the amygdala body (including the anterior-superior aspect adjacent to the basal nucleus). Also, in patients, increased volumetric asymmetry tended to be correlated with increased left/right shape asymmetry. Furthermore, a combined analysis of volume and shape asymmetry resulted in improved differentiation between groups. Classification function analyses correctly classified 70% of cases using volume, 73.3% using shape, and 87% using combined volume and shape measures. These findings suggest that shape provides important new information toward characterizing the pathophysiology of schizophrenia, and that combining volume and shape measures provides improved group discrimination in studies investigating brain abnormalities in schizophrenia. An evaluation of shape deformations also suggests local abnormalities in the amygdala-hippocampal complex in schizophrenia.