Clinical correlates of thalamus volume deficits in anti-psychotic-naïve schizophrenia patients: A 3-Tesla MRI study

Abstract

Background:Thalamus, the sensory and motor gateway to the cortex, plays an important role in cognitive and perceptual disturbances in schizophrenia. Studies examining the volume of the thalamus in schizophrenia have reported conflicting findings due to the presence of potential confounding factors such as low-resolution imaging and anti-psychotics. The thalamus volume in anti-psychotic-naïve patients determined using high-resolution 3-Tesla magnetic resonance imaging (MRI) has not yet been examined.Materials and Methods:Using 3-Tesla MRI, this study for the first time examined anti-psychotic-naïve schizophrenia patients (n=18; M:F:11:7) in comparison with healthy controls (n=19;M:F:9:10) group-matched for age, sex, handedness, education, and socioeconomic status. The volume of the thalamus was measured using a three-dimensional, interactive, semi-automated analysis with good inter-rater and intra-rater reliability. Psychopathology was assessed using the Scale for Assessment of Negative Symptoms (SANS) and the Scale for Assessment of Positive Symptoms (SAPS).Results:Right, left, and total thalamus volumes of patients were significantly smaller than those of controls after controlling for the potential confounding effect of intracranial volume. Thalamus volumes had significant positive correlation with positive symptoms score (SAPS) and significant negative correlation with negative symptoms score (SANS).Conclusions:Thalamus volume deficits in anti-psychotic-naïve schizophrenia patients support a neurodevelopmental pathogenesis. The contrasting correlation of thalamus volume deficits with psychopathology scores suggests that contrasting pruning aberrations underlie symptom genesis in schizophrenia.

Neuropil Pruning in Early-Course Schizophrenia: Immunological, Clinical, and Neurocognitive Correlates

“…Prior studies show smaller thalamus volume in schizophrenia (75–77) that correlated with both negative and positive symptoms (76) and cognitive performance (78). Correlation of impaired sustained attention (increased Go-No-Go response time) underscores the clinical significance of increased thalamic pruning.…”

Neurobiological Correlates of Delusion: Beyond the Salience Attribution Hypothesis

“…Therefore, observations of volume alterations associated with delusions in unmedicated patients as described by Gur et al [19] are highly relevant for the understanding of the development of delusions and further positive symptoms in schizophrenia. However, a study of Rao et al [21] in unmedicated schizophrenia patients observed a significant reduction rather than an increase in thalamic volumes in schizophrenia patients compared to healthy controls. In spite of the overall reduction in thalamus volumes, and in accordance with the observations of Gur et al [19], a significant positive correlation was observed between individual volumes of the thalamus and positive symptoms [21].…”

“…However, a study of Rao et al [21] in unmedicated schizophrenia patients observed a significant reduction rather than an increase in thalamic volumes in schizophrenia patients compared to healthy controls. In spite of the overall reduction in thalamus volumes, and in accordance with the observations of Gur et al [19], a significant positive correlation was observed between individual volumes of the thalamus and positive symptoms [21]. One longitudinal comparison further suggested that pituitary enlargement correlates with poor improvement of delusions during the observation period [22].…”

Pathogenetic and therapeutic perspectives on neurocognitive models in psychiatry: A synthesis of behavioral, brain imaging, and biological studies

“…Right, left, and total thalamus volumes of patients were significantly smaller than those of controls and volumes had differential correlation with symptom dimensions. Findings suggested contrasting pruning aberrations to underlie different symptom genesis in schizophrenia[36] [Figure 6]. …”