Sex differences in the absence of massa intermedia in patients with schizophrenia versus healthy controls

Exploring the impact of the interthalamic adhesion on human cognition: insights from healthy subjects and thalamic stroke patients

The interthalamic adhesion (IA) is a structure that connects the median borders of both thalami. Its anatomical variants and functions remain poorly studied. The main objective of this study was to explore the role of the IA on cognition. 42 healthy subjects and 40 patients with chronic isolated thalamic strokes underwent a neuroimaging and a neuropsychological assessment. The presence, absence, or lesion of the IA and its anatomical variants were evaluated. 76% of participants had an IA, with a higher prevalence among women (92%) than men (61%). The presence or absence of an IA did not affect the neuropsychological performance of healthy subjects nor did the type of IA variant. Across all the tests and when compared to healthy subjects using a Bayesian rmANOVA, patients exhibiting more cognitive impairments were those without an IA (n = 10, BF10 = 10,648), while those with an IA were more preserved (n = 18, BF10 = 157). More specifically, patients without an IA performed more poorly in verbal memory or the Stroop task versus healthy subjects. This was not explained by age, laterality of the infarct, volume or localization of the lesion. Patients with a lesioned IA (n = 12) presented a similar trend to patients without an IA, which could however be explained by a greater volume of lesions. The IA does not appear to play a major role in cognition in healthy subjects, but could play a compensatory role in patients with thalamic lesions.

Massa intermedia in adults: incidence, dimension, location and clinical importance

PURPOSE

This retrospective magnetic resonance imaging investigation aimed to obtain information related to the anatomy of the massa intermedia (MI) in an adult population.

METHODS

The work conducted on MRI views of 1058 (539 males and 519 females) healthy adult samples aged with 48.93 ± 17.63 years. Initially, the presence or absence of MI was noted, and then if present, its numbers and location in the third ventricle were recorded. Its horizontal (HDMI) and vertical (VDMI) diameters were measured on MRI views, while the cross-sectional area (CSAMI) was calculated using its diameters.

RESULTS

MI was missing in 2.6% (27 cases) of 1058 adult samples. Six subjects (0.6%) had a double MI. HDMI, VDMI and CSAMI were measured as 4.83 ± 1.01 mm, 4.86 ± 0.98 mm, and 19.11 ± 7.23 mm2, respectively. MI size did not show a significant alteration from 19 up to 49 years, but then its size distinctly decreased between 50 and 60 years. After age 60, MI dimension did not display an important change. MI was settled in the antero-superior quadrant in 929 cases (90.63% of 1025 subjects), in the postero-superior quadrant in 22 cases (2.15%), in the antero-inferior quadrant in 32 cases (3.12%), in the postero-inferior quadrant in 8 cases (0.78%), and in the central part in 34 cases (3.32%).

CONCLUSIONS

The size, position and incidence of MI were not affected by sex, and its position and incidence were not affected by adult age periods. In adults, MI size demonstrated a significant decrease in the middle age.

Coupling between the prelimbic cortex, nucleus reuniens, and hippocampus during NREM sleep remains stable under cognitive and homeostatic demands

The interplay between the medial prefrontal cortex and hippocampus during non-rapid eye movement (NREM) sleep contributes to the consolidation of contextual memories. To assess the role of the thalamic nucleus reuniens (Nre) in this interaction, we investigated the coupling of neuro-oscillatory activities among prelimbic cortex, Nre, and hippocampus across sleep states and their role in the consolidation of contextual memories using multi-site electrophysiological recordings and optogenetic manipulations. We showed that ripples are time-locked to the Up state of cortical slow waves, the transition from UP to DOWN state in thalamic slow waves, the troughs of cortical spindles, and the peaks of thalamic spindles during spontaneous sleep, rebound sleep and sleep following a fear conditioning task. In addition, spiking activity in Nre increased before hippocampal ripples, and the phase-locking of hippocampal ripples and thalamic spindles during NREM sleep was stronger after acquisition of a fear memory. We showed that optogenetic inhibition of Nre neurons reduced phase-locking of ripples to cortical slow waves in the ventral hippocampus whilst their activation altered the preferred phase of ripples to slow waves in ventral and dorsal hippocampi. However, none of these optogenetic manipulations of Nre during sleep after acquisition of fear conditioning did alter sleep-dependent memory consolidation. Collectively, these results showed that Nre is central in modulating hippocampus and cortical rhythms during NREM sleep.

Prevalence of the interthalamic adhesion in the human brain: a review of literature

The interthalamic adhesion (IA) is a midline structure connecting the two thalami. Though it has been studied for centuries its exact function remains elusive. Early studies had noted its peculiar absence even among some healthy individuals. Population studies have investigated the differences in prevalence of IA in pathologic conditions and healthy controls. However, there is a general lack of consensus on IA prevalence in the healthy population. Understanding the true prevalence is critical in providing context for future studies, as well as uncovering further clues regarding IA's function. We systematically reviewed the existing literature to evaluate the prevalence of IA. The average prevalence among reviewed studies was higher than previously reported, at 87.3%. Studies utilizing magnetic resonance imaging rather than cadaveric specimens reported higher rates of IA prevalence. A higher prevalence among females was noted throughout the literature that persisted regardless of acquisition modality utilized.

Massa intermedia of the thalamus: an anatomical study using magnetic resonance imaging

PURPOSE

Few studies have explored the morphology of massa intermedia (MI). The aim of the present study was to characterize it using magnetic resonance imaging (MRI).

METHODS

A total of 205 patients were enrolled in this study. Following initial examinations with conventional MRI sequences, thin-slice coronal and sagittal T2-weighted imaging was performed. For MI localization, the third ventricle was arbitrarily divided into nine areas on the midsagittal image.

RESULTS

MI was identified in 93% of the total patients-89% in male and 91% in female patients. Among them, 68% showed a single, styloid-shaped MI with variable thickness and cross sectional configuration, followed by broad and double MIs that were found in 18% and 10% patients, respectively. In the anteroposterior dimension, 99% of the MIs were identified in the middle third area, followed by the posterior third area. In the supero-inferior dimension, 95% of the MIs were identified in the middle third area, followed by the upper third area. With a significant difference, a broad MI was more frequently found in women than in men.

CONCLUSIONS

MIs are commonly located in the middle third of the third ventricle as a single commissure with high morphological variability. Compared to men, women may have a well-developed, broader MI.

Dump the "dimorphism": Comprehensive synthesis of human brain studies reveals few male-female differences beyond size

With the explosion of neuroimaging, differences between male and female brains have been exhaustively analyzed. Here we synthesize three decades of human MRI and postmortem data, emphasizing meta-analyses and other large studies, which collectively reveal few reliable sex/gender differences and a history of unreplicated claims. Males' brains are larger than females' from birth, stabilizing around 11 % in adults. This size difference accounts for other reproducible findings: higher white/gray matter ratio, intra- versus interhemispheric connectivity, and regional cortical and subcortical volumes in males. But when structural and lateralization differences are present independent of size, sex/gender explains only about 1% of total variance. Connectome differences and multivariate sex/gender prediction are largely based on brain size, and perform poorly across diverse populations. Task-based fMRI has especially failed to find reproducible activation differences between men and women in verbal, spatial or emotion processing due to high rates of false discovery. Overall, male/female brain differences appear trivial and population-specific. The human brain is not "sexually dimorphic."

The adhesio interthalamica as a neuroanatomical marker of structural differences in healthy adult population

The adhesio interthalamica (AI) is a small midline brain structure that connects the left and right thalamus. According to in vivo data, between 2.3 and 22.3% of the general population lack the AI, and the question of whether this absence is more prevalent in males than in females is a matter of debate. Despite the existence of these demographic figures, it remains unclear how this distinctive feature affects healthy people, or what specific anatomic profile is related to the presence or absence of the AI. The aim of this study was to investigate whole-brain gray matter (GM) volumetric differences depending on the presence or absence of the AI. A total of 240 healthy adult volunteers completed one MRI scanning session. After the AI assessment, the data from 110 participants were included in the final sample, of which 12.9% of the participants (n = 31) presented complete AI absence vs. 32.9% of participants (n = 79) who presented complete AI presence. Then, whole-brain group comparison analysis revealed that the absent AI brain, compared to the present AI brain, was associated with lower GM volume in the premotor cortex, inferior frontal gyrus, and anterior temporal cortex. Interestingly, neuroscience research has linked emotional and cognitive control brain processing to the latter two regions. The importance of these findings lies in providing a neuroanatomical profile for the absent AI brain in healthy human adults.

Structural connectivity of the human massa intermedia: A probabilistic tractography study

The role of massa intermedia (MI) is poorly understood in humans. Recent studies suggest its presence may play a role in normal human neurocognitive function while prior studies have shown the absence of MI correlated with psychiatric disorders. There is growing evidence that MI is likely a midline white matter conduit, responsible for interhemispheric connectivity, similar to other midline commissures. MI presence was identified in an unrelated sample using the Human Connectome Project database. MI structural connectivity maps were created and gray matter target regions were identified using probabilistic tractography of the whole brain. Probabilistic tractography revealed an extensive network of connections between MI and limbic, frontal and temporal lobes as well as insula and pericalcarine cortices. Women compared to men had stronger connectivity via their MI. The presented results support the role of MI as a midline commissure with strong connectivity to the amygdala, hippocampus, and entorhinal cortex.

The thalamic midline nucleus reuniens: potential relevance for schizophrenia and epilepsy

Anatomical, electrophysiological and behavioral studies in rodents have shown that the thalamic midline nucleus reuniens (RE) is a crucial link in the communication between hippocampal formation (HIP, i.e., CA1, subiculum) and medial prefrontal cortex (mPFC), important structures for cognitive and executive functions. A common feature in neurodevelopmental and neurodegenerative brain diseases is a dysfunctional connectivity/communication between HIP and mPFC, and disturbances in the cognitive domain. Therefore, it is assumed that aberrant functioning of RE may contribute to behavioral/cognitive impairments in brain diseases characterized by cortico-thalamo-hippocampal circuit dysfunctions. In the human brain the connections of RE are largely unknown. Yet, recent studies have found important similarities in the functional connectivity of HIP-mPFC-RE in humans and rodents, making cautious extrapolating experimental findings from animal models to humans justifiable. The focus of this review is on a potential involvement of RE in schizophrenia and epilepsy.

Cavum septum pellucidum and adhesio interthalamica in schizophrenia: an MRI study

Several studies have independently suggested that patients with schizophrenia are more likely to have an enlarged cavum septum pellucidum (CSP) and an absent adhesio interthalamica (AI), respectively. However, neither finding has been consistently replicated and it is unclear whether there is an association between these two midline brain abnormalities. Thus, we compared the prevalence of absent AI and the prevalence, size and volume of CSP in 38 patients with schizophrenia and 38 healthy controls using magnetic resonance imaging (MRI). There were no between group differences in the presence or volume of CSP; however, an enlarged CSP was commoner among patients than controls. There was also a positive correlation between CSP ratings and volumes. No differences in the presence or absence of the AI were found between patients and controls; however, an absent AI was commoner in male patients with schizophrenia than females. There was absolutely no overlap between the presence of a large CSP and an absence of AI. In conclusion, our findings are in line with several case series and other MRI investigations that have shown a higher incidence of putatively developmental brain abnormalities in patients with schizophrenia, particularly in males, and support the neurodevelopmental model of this disorder.

Thalamic Massa Intermedia in Children with and without Midline Brain Malformations

BACKGROUND AND PURPOSE

The massa intermedia is a normal midline transventricular thalamic connection. Massa intermedia aberrations are common in schizophrenia, Chiari II malformation, X-linked hydrocephalus, Cornelia de Lange syndrome, and diencephalic-mesencephalic junction dysplasia, among others. We have noticed that massa intermedia abnormalities often accompany other midline malformations. The massa intermedia has never been formally evaluated in a group of exclusively pediatric patients, to our knowledge. We sought to compare and contrast the prevalence, size, and location of the massa intermedia in pediatric patients with and without congenital midline brain abnormalities.

MATERIALS AND METHODS

Successive 3T brain MR imaging examinations from pediatric patients with and without midline malformations were procured from the imaging data base at a pediatric hospital. Massa intermedia presence, size, morphology, and position were determined using 3D-TIWI with 1-mm isotropic resolution. The brain commissures, septum pellucidum, hypothalamus, hippocampus, vermis, and brain stem were evaluated to determine whether alterations were related to or predictive of massa intermedia abnormalities.

RESULTS

The massa intermedia was more frequently absent, dysmorphic, and/or displaced in patients with additional midline abnormalities than in those without. The massa intermedia was absent in 40% of patients with midline malformations versus 12% of patients with normal findings (P < .001). Massa intermedia absence, surface area, and morphology were predictable by various attributes and alterations of the commissures, hippocampus, hypothalamus, vermis, brain stem, and third ventricle.

CONCLUSIONS

Most pediatric patients have a thalamic massa intermedia centered in the anterior/superior third ventricle. Massa intermedia abnormalities are commonly associated with other midline malformations. Normal-variant massa intermedia absence is a diagnosis of exclusion.

The nucleus reuniens of the thalamus sits at the nexus of a hippocampus and medial prefrontal cortex circuit enabling memory and behavior

The nucleus reuniens of the thalamus (RE) is a key component of an extensive network of hippocampal and cortical structures and is a fundamental substrate for cognition. A common misconception is that RE is a simple relay structure. Instead, a better conceptualization is that RE is a critical component of a canonical higher-order cortico-thalamo-cortical circuit that supports communication between the medial prefrontal cortex (mPFC) and the hippocampus (HC). RE dysfunction is implicated in several clinical disorders including, but not limited to Alzheimer's disease, schizophrenia, and epilepsy. Here, we review key anatomical and physiological features of the RE based primarily on studies in rodents. We present a conceptual model of RE circuitry within the mPFC-RE-HC system and speculate on the computations RE enables. We review the rapidly growing literature demonstrating that RE is critical to, and its neurons represent, aspects of behavioral tasks that place demands on memory focusing on its role in navigation, spatial working memory, the temporal organization of memory, and executive functions.

Factors associated with the size of the adhesio interthalamica based on 3.0-T magnetic resonance images

BACKGROUND

Adhesio interthalamica (AI) is a small structure connecting bilateral thalami.

PURPOSE

To evaluate the effects of patient age, sex, and lateral diameter of the third ventricle on the long diameter of the AI using multivariate analyses based on magnetic resonance (MR) images obtained with 3.0-T scanners.

MATERIAL AND METHODS

This clinical retrospective study included images of 153 patients who underwent MR examination using 3.0-T scanners. The long diameter of the AI and lateral diameter of the third ventricle were measured on images in the mid-sagittal plane and axial plane at the anterior commissure, respectively. Univariate and multivariate analyses were performed.

RESULTS

AI was observed in 138 patients (70 men, 68 women; mean age = 63.7 ± 13.7 years; mean AI size =5.34 ± 1.63 mm). By univariate analyses, patient age (r = -0.262, P = 0.002), sex ( P = 0.010), and lateral diameter of the third ventricle (r = -0.642, P < 0.001) were significantly associated with the long diameter of the AI. With multiple linear regression analyses with a stepwise selection of parameters, only the lateral diameter of the third ventricle (estimate = -0.432, P < 0.001) was significantly associated with the long diameter of the AI. The lateral diameter of the third ventricle was longer in patients without AI (15 patients) than in those with AI ( P = 0.006).

CONCLUSION

The lateral diameter of the third ventricle was a major factor negatively associated with the long diameter of the AI.

Adhesio interthalamica and cavum septum pellucidum in mesial temporal lobe epilepsy

The absence of the adhesio interthalamica (AI; also called interthalamic adhesion or massa intermedia) and the presence of a large cavum septum pellucidum (CSP) later in life have been related to neurodevelopmental alterations and have not been systematically investigated in epilepsy to date. This study carried out a MRI evaluation of the AI and CSP in a large sample with mesial temporal lobe epilepsy (MTLE). A total of 179 patients, classified according to the side of the epileptogenic focus, and 156 age- and sex-balanced healthy controls were assessed. Between-group comparisons of the prevalence and length of both AI and CSP were conducted. Neuropsychological assessments were also performed in 160 MTLE patients. The patients exhibited reduction in the AI prevalence (P < 0.05; FDR-uncorrected) and length (P < 0.05; FDR-corrected) when compared to controls. Patients without AI showed lower scores in a proportion of neuropsychological tests than patients with AI. No CSP differences were found between MTLE patients and controls. These results support that AI anomalies have clinical significance in MTLE, as well as indicate that neurodevelopmental alterations may be implicated in this disorder.

Thalamic Massa Intermedia Duplication in a Dysmorphic 14 month-old Toddler

The massa intermedia is an inconstant parenchymal band connecting the medial thalami. It may be thickened in various disease processes such as Chiari II malformation or absent in other disease states. However, the massa intermedia may also be absent in up to 30% of normal human brains. To the best of my knowledge, detailed imaging findings of massa intermedia duplication have only been described in a single case report. An additional case of thalamic massa intermedia duplication discovered on a routine brain MR performed for dysmorphic facial features is reported herein.

Variability of Forebrain Commissures in Callosal Agenesis: A Prenatal MR Imaging Study

BACKGROUND AND PURPOSE

Agenesis of the corpus callosum, even when isolated, may be characterized by anatomic variability. The aim of this study was to describe the types of other forebrain commissures in a large cohort of randomly enrolled fetuses with apparently isolated agenesis of the corpus callosum at prenatal MR imaging.

MATERIALS AND METHODS

All fetuses with apparent isolated agenesis of the corpus callosum undergoing prenatal MR imaging from 2004 to 2014, were evaluated for the presence of the anterior or a vestigial hippocampal commissure assessed in consensus by 2 pediatric neuroradiologists.

RESULTS

Overall, 62 cases of agenesis of the corpus callosum were retrieved from our data base. In 3/62 fetuses (4.8%), no forebrain commissure was visible at prenatal MR imaging, 23/62 fetuses (37.1%) presented with only the anterior commissure, and 20/62 fetuses (32.3%) showed both the anterior commissure and a residual vestigial hippocampal commissure, whereas in the remaining 16/62 fetuses (25.8%), a hybrid structure merging a residual vestigial hippocampal commissure and a rudiment of the corpus callosum body was detectable. Postnatal MR imaging, when available, confirmed prenatal forebrain commissure findings.

CONCLUSIONS

Most fetuses with apparent isolated agenesis of the corpus callosum showed at least 1 forebrain commissure at prenatal MR imaging, and approximately half of fetuses also had a second commissure: a vestigial hippocampal commissure or a hybrid made of a hippocampal commissure and a rudimentary corpus callosum body. Whether such variability is the result of different genotypes and whether it may have any impact on the long-term neurodevelopmental outcome remains to be assessed.

Neuroimaging features of Cornelia de Lange syndrome

BACKGROUND

Cornelia de Lange syndrome is a rare genetic disease characterized by distinctive facial dysmorphia and dwarfism. Multiple organ system involvement is typical. Various central nervous system (CNS) aberrations have been described in the pathology literature; however, the spectrum of neuroimaging manifestations is less well documented.

OBJECTIVE

To present neuroimaging findings from a series of eight patients with Cornelia de Lange syndrome.

MATERIALS AND METHODS

The CT/MR database at a single academic children's hospital was searched for the terms "Cornelia," "Brachmann" and "de Lange." The search yielded 18 exams from 16 patients. Two non-CNS and six exams without available images were excluded. Ten exams from eight patients were evaluated by a board-certified neuroradiologist.

RESULTS

All patients had skull base dysplasia, most with an unusual coronal basioccipital cleft (7/8). All brain MR exams showed microcephaly, volume loss and gyral simplification (5/5). Six patients had an absent massa intermedia. Four patients had small globe anterior segments; three had optic pathway hypoplasia. Basilar artery fenestration was present in two patients; vertebrobasilar hypoplasia was present in one patient. The inner ear vestibules were dysplastic in two patients. One patient had pachymeningeal thickening. Spinal anomalies included scoliosis, segmentation anomalies, endplate irregularities, basilar invagination, foramen magnum stenosis and tethered spinal cord.

CONCLUSION

Typical imaging manifestations of Cornelia de Lange syndrome include skull base dysplasia with coronal clival cleft, cerebral and brainstem volume loss, and gyral simplification. Membranous labyrinth dysplasia, anterior segment and optic pathway hypoplasia, basilar artery fenestration, absent massa intermedia and spinal anomalies may also be present.

Gender identity disorder and schizophrenia: neurodevelopmental disorders with common causal mechanisms?

Gender identity disorder (GID), recently renamed gender dysphoria (GD), is a rare condition characterized by an incongruity between gender identity and biological sex. Clinical evidence suggests that schizophrenia occurs in patients with GID at rates higher than in the general population and that patients with GID may have schizophrenia-like personality traits. Conversely, patients with schizophrenia may experience alterations in gender identity and gender role perception. Neurobiological research, including brain imaging and studies of finger length ratio and handedness, suggests that both these disorders are associated with altered cerebral sexual dimorphism and changes in cerebral lateralization. Various mechanisms, such as Toxoplasma infection, reduced levels of brain-derived neurotrophic factor (BDNF), early childhood adversity, and links with autism spectrum disorders, may account for some of this overlap. The implications of this association for further research are discussed.

A magnetic resonance imaging study of adhesio interthalamica in clinical subtypes of schizophrenia

CONTEXT

Previous studies have suggested subtle anatomical brain differences between patients with schizophrenia and healthy control subjects. However, the results are inconsistent and there is no study investigating the various subtypes of this mental disorder separately.

AIM

This study was conducted to compare the rate of absence of adhesio interthalamica (AI), a midline brain structure, between 3 subtypes of schizophrenia (paranoid, undifferentiated, and residual) and healthy control group, using magnetic resonance imaging (MRI).

MATERIALS AND METHODS

A total of 29 schizophrenia patients (21 men, 8 women) of three subtypes (paranoid, undifferentiated, and residual) were compared with 29 age- and gender-matched healthy controls. All subjects underwent 3-D brain MRI of full coronal series, 1.5-mm slices without interslice gaps. If the grey matter band connecting the thalami could not be identified on two or more coronal adjacent slices, the AI was considered as absent. The results were statistically analyzed.

RESULTS

The incidence rate of AI absence in patients with heterogenous subtypes of schizophrenia was was similar to control group, even when patients and controls of each gender were compared separately (P>0.05). In residual subtype, patients showed a significant priority in AI absence in comparison with the control group (P=0.041), which was not seen in paranoid and undifferentiated subtypes (P>0.05).

CONCLUSION

Residual subtype of schizophrenia is associated with higher rate of AI absence in this study. Subsequent studies are required to determine if the absence of AI is a cause of residual schizophrenia or an effect.

Longitudinal follow-up of cavum septum pellucidum and adhesio interthalamica alterations in first-episode psychosis: a population-based MRI study

BACKGROUND

Neurodevelopmental alterations have been described inconsistently in psychosis probably because of lack of standardization among studies. The aim of this study was to conduct the first longitudinal and population-based magnetic resonance imaging (MRI) evaluation of the presence and size of the cavum septum pellucidum (CSP) and adhesio interthalamica (AI) in a large sample of patients with first-episode psychosis (FEP).

METHOD

FEP patients (n=122) were subdivided into schizophrenia (n=62), mood disorders (n=46) and other psychosis (n=14) groups and compared to 94 healthy next-door neighbour controls. After 13 months, 80 FEP patients and 52 controls underwent a second MRI examination.

RESULTS

We found significant reductions in the AI length in schizophrenia FEP in comparison with the mood disorders and control subgroups (longer length) at the baseline assessment, and no differences in any measure of the CSP. By contrast, there was a diagnosis×time interaction for the CSP length, with a more prominent increase for this measure in the psychosis group. There was an involution of the AI length over time for all groups but no diagnosis×time interaction.

CONCLUSIONS

Our findings suggest that the CSP per se may not be linked to the neurobiology of emerging psychotic disorders, although it might be related to the progression of the disease. However, the fact that the AI length was shown to be shorter at the onset of the disorder supports the neurodevelopmental model of schizophrenia and indicates that an alteration in this grey matter junction may be a risk factor for developing psychosis.

Tract-specific analysis of white matter integrity disruption in schizophrenia

Several studies have suggested that white matter integrity is disrupted in some brain regions in patients with schizophrenia. The purpose of this study was to assess the white matter integrity of the cingulum, uncinate fasciculus, fornix, and corpus callosum using diffusion tensor imaging (DTI). Participants comprised 39 patients with schizophrenia (19 males and 20 females) and 40 age-matched normal controls (20 males and 20 females). We quantitatively assessed the fractional anisotropy (FA) and apparent diffusion coefficient (ADC) of the anterior cingulum, body of the cingulum, uncinate fasciculus, fornix, and corpus callosum on a tract-specific basis using diffusion tensor tractography (DTT). Group differences in FA and ADC between the patients and normal controls were sought. Additional exploratory analyses of the relationship between the FA or ADC and four clinical parameters (i.e., illness duration, positive symptom scores, negative symptom scores, and medication dosage) were performed. Results were analyzed in gender-combined and gender-separated group comparisons. FA was significantly lower on both sides of the anterior cingulum, uncinate fasciculus, and fornix in the schizophrenia patients irrespective of gender group separation. In the gender-combined analyses, significantly higher ADC values were demonstrated in the schizophrenia patients in both sides of the anterior cingulum, body of the cingulum and uncinate fasciculus, the left fornix, and the corpus callosum, compared with those of the normal controls. In the gender-separated analyses, the male patients showed higher ADC in the left anterior cingulum, the bilateral cingulum bodies, and the bilateral uncinate fasciculi. The female patients showed higher ADC in the right anterior cingulum, the left fornix, and the bilateral uncinate fasciculus. In correlation analyses, a significant negative correlation was found between illness duration and ADC in the right anterior cingulum in the gender-combined analyses. The gender-separated analyses found that the male patients had a significant negative correlation between negative symptom scores and FA in the right fornix, a positive correlation between illness duration and FA in the right anterior cingulum, and a negative correlation between illness duration and FA in the left uncinate fasciculus. Our DTI study showed that the integrity of white matter is disrupted in patients with schizophrenia. The results of our sub-analyses suggest that changes in FA and ADC may be related to negative symptom scores or illness duration.

Adhesio interthalamica alterations in schizophrenia spectrum disorders: A systematic review and meta-analysis

Magnetic resonance imaging (MRI) studies have reported a variety of brain abnormalities in association with schizophrenia. These include a higher prevalence of an absent adhesio interthalamica (AI; also known massa intermedia), a gray matter junction that is present between the two thalami in approximately 80% of healthy subjects. In this meta-analytic review, we describe and discuss the main AI MRI findings in schizophrenia spectrum disorders (SSDs) to date. The MEDLINE and ISI Web of Knowledge databases were searched up to December 2010, for studies that used MRI to assess AI in patients with SSD and controls. From fourteen potential reports, eleven were eligible to be part of the current review. These studies included 822 patients with SSD and 718 healthy volunteers. There was a large degree of variability in the MRI methods they employed. Patients with SSD had a higher prevalence of absent AI than healthy volunteers (odds ratio = 1.98; 95% confidence interval 1.33-2.94; p = 0.0008). This association was evident in both male and female SSD subjects, and there was no evidence that the prevalence was related to age or duration of illness. The significance of the absence of an AI for SSD may be clarified by studies in large, longitudinal community-based samples using standardized methods.

Complex pattern of cortical thinning in schizophrenia: results from an automated surface based analysis of cortical thickness

A considerable body of evidence from structural brain imaging studies suggests that patients with schizophrenia have significant alterations of gray matter density. Additionally, recently developed surface-based analysis approaches demonstrate reduced cortical thickness in patients with schizophrenia. However, the number of studies employing this relatively new method is still limited. Specifically, little is known about changes in cortical thickness in schizophrenia patients whose duration of illness is relatively short. Therefore, the present study sought to examine cortical thickness in a large sample of patients with adult onset schizophrenia and an average duration of illness of 4.4 years, using an automated analysis method over the entire cortex. A significantly decreased cortical thickness in prefrontal and temporolimbic regions as well as parieto-occipital cortical areas was hypothesized. A sample of 58 patients with schizophrenia and 58 age- and sex-matched healthy controls was investigated using high-resolution magnetic resonance imaging (MRI) and an automated algorithm for extraction of the cortical surface in order to assess local cortical thinning across the entire cerebrum. Significant reduction of cortical thickness in schizophrenia was found in a spatially complex pattern of focal anatomical regions. This pattern comprised the dorsolateral prefrontal cortex as well as the medial prefrontal cortex, lateral temporal cortices, left entorhinal cortex, posterior cingulate cortex, precuneus and lingual cortex, bilaterally. A complex fronto-temporo-parietal pattern of reduced cortical thickness in schizophrenia was observed. This pattern is consistent with a disruption of neurofunctional networks previously implicated in the pathophysiology of schizophrenia.

Midline brain structures in patients with current and remitted major depression

Brain morphologic changes of limbic-cortical regions have been reported in major depressive disorder (MDD). However, it remains largely unknown whether MDD is associated with abnormalities in midline brain structures, which play a critical role in limbic-cortical connectivity, and whether such changes reflect state or trait markers of the disorder. We used magnetic resonance imaging to investigate the length of the adhesio interthalamica (AI) and cavum septum pellucidum (CSP) in 29 currently depressed patients, 27 remitted depressed patients, and 33 age- and gender-matched healthy control subjects. The currently depressed patients had a significantly shorter AI compared with controls, but there was no difference in the AI length between the remitted patients and controls. The AI length in the overall patient group was negatively correlated with the severity of symptoms of "loss of interest" at the time of scanning. Furthermore, the patients with co-morbid anxiety disorders tended to have a shorter AI compared with those without. The CSP length and prevalence of a large CSP (>or=6 mm) did not differ between the groups. Although a comprehensive investigation of medication effects was not possible due to incomplete medication data, these findings suggest that a shorter length of the AI may be associated with state-related brain changes in major depression rather than a stable marker of illness vulnerability. Whether the AI length exhibits ongoing changes across the course of the illness remains to be determined in longitudinal studies.

Midline brain structures in teenagers with first-presentation borderline personality disorder

Brain morphologic changes have been reported in borderline personality disorder (BPD), but it remains largely unknown whether BPD is associated with midline brain abnormalities. We used magnetic resonance imaging to investigate the length of the adhesio interthalamica (AI) and cavum septum pellucidum (CSP) as well as third ventricular volume in 20 teenagers with first-presentation BPD and 20 healthy controls. While the CSP length did not differ between the groups, the AI was significantly shorter in BPD patients than in controls. Furthermore, the BPD patients had a significantly larger third ventricle than controls. These preliminary findings suggest that ongoing neuroimaging studies should further evaluate a potential involvement of midline brain structures in the pathogenesis of BPD.

Prevalence and length of the adhesio interthalamica in schizophrenia spectrum disorders

We used magnetic resonance imaging to investigate the prevalence and length of the adhesio interthalamica (AI) in 72 schizophrenia patients, 47 schizotypal disorder patients, and 81 healthy controls. The AI was more often absent and shorter in both disorders than in controls, possibly reflecting common neurodevelopmental abnormalities in the schizophrenia spectrum.

Adhesio interthalamica in individuals at high-risk for developing psychosis and patients with psychotic disorders

Abnormal neurodevelopment in midline structures such as the adhesio interthalamica (AI) has been reported in psychotic disorders, but it is unknown whether individuals at risk for the disorder share the AI findings observed in patients with florid psychosis. Magnetic resonance imaging of 162 patients with first-episode psychosis (FEP), 89 patients with chronic schizophrenia, 135 individuals at ultra high-risk (UHR) of psychosis (of whom 39 later developed psychosis), and 87 healthy controls were used to investigate the length and prevalence of the AI. The relation of the AI length to lateral ventricular enlargement was also explored. The patients with FEP and chronic schizophrenia as well as UHR individuals had a shorter AI than the controls, but there was no difference in the AI findings between the UHR individuals who did and did not subsequently develop psychosis. There was a negative correlation between the AI length and lateral ventricular volume in all the diagnostic groups. The absence of the AI was more common in the chronic schizophrenia patients when compared with all other groups. These results support the notion that the AI absence or shorter length could be a neurodevelopmental marker related to vulnerability to psychopathology, but also suggest that schizophrenia patients may manifest progressive brain changes related to ongoing atrophy of the AI after the onset.

Absence and size of massa intermedia in patients with schizophrenia and bipolar disorder

OBJECTIVE

To evaluate the absence and size of massa intermedia (MI), a midline thalamic structure, and its gender-specific alteration in patients with schizophrenia and bipolar disorder.

METHODS

Thirty-five patients with schizophrenia (17 females and 18 males), 21 patients with bipolar disorder (15 females and 6 males) and 89 healthy controls (50 females and 39 males) were evaluated by magnetic resonance imaging. Thin-slice magnetic resonance images of the brain were evaluated. MI was determined in coronal and sagittal images, and area of the MI was measured on the sagittal plane.

RESULTS

Females had a significantly lower incidence of absent MI compared with males in the healthy control group. The absence of MI in schizophrenia and bipolar patients was not higher than the incidence in healthy controls. The size of MI showed a gender difference. The mean MI area size was smaller in female schizophrenia patients than in female controls, while no significant difference was observed between male schizophrenia patients and their controls.

CONCLUSIONS

The size of MI, a gender difference midline structure, is smaller in females with schizophrenia, and the results of this study support other studies of structural aberration of the thalamus and other midline structures in the brains of patients with schizophrenia.

The association of genotypic combination of the DRD3 and BDNF polymorphisms on the adhesio interthalamica and medial temporal lobe structures

Abnormal neurodevelopment in midline structures such as the adhesio interthalamica (AI), as well as in the medial temporal lobe structures has been implicated in schizophrenia, while its genetic mechanism is unknown. This magnetic resonance imaging study investigated the effect of the genotypic combination of the dopamine D3 receptor (DRD3) Ser9Gly and brain-derived neurotrophic factor (BDNF) Val66Met polymorphisms on the AI length and volumetric measures of the medial temporal lobe structures (amygdala, hippocampus, and parahippocampal gyrus) in 33 schizophrenia patients and 29 healthy controls. The subjects with a combination of the Ser/Ser genotype of DRD3 and Met-containing genotypes of BDNF (high-risk combination) had a shorter AI than those without it in the healthy controls, but not in the schizophrenia patients. The subjects carrying the high-risk combination had a smaller posterior hippocampus than those without it for both diagnostic groups. These genotypic combination effects on brain morphology were not explained by the independent effect of each polymorphism. These findings suggest the effect of gene-gene interaction between the DRD3 and BDNF variations on brain morphology in midline and medial temporal lobe structures, but do not support its specific role in the pathogenesis of schizophrenia.

Structural abnormalities of the adhesio interthalamica and mediodorsal nuclei of the thalamus in schizophrenia

OBJECTIVE

Several studies have suggested the existence of thalamic volume reduction in patients with schizophrenia. However, the precise locus of volume reduction within the thalamus has scarcely been investigated. On the other hand, underdevelopment of the adhesio interthalamica [AI; Danos, P., Baumann, B., Kramer, A., Bernstein, H.G., Stauch, R., Krell, D., Falkai, P., Bogerts, B., 2003. Volumes of association thalamic nuclei in schizophrenia: a post-mortem study. Schizophrenia Res. 60 141-155], which bridges bilateral medial edges of the thalamus, has been reported in patients with schizophrenia. We assessed the volumes of mediodorsal nuclei (MDN) of thalami, level of AI development, and their interrelationship, in patients with schizophrenia.

METHOD

A sample of 58 patients with schizophrenia and 44 matched healthy volunteers underwent assessment with high-resolution 1-mm-thick anatomical MRI. Volume measurements of the MDN of the thalamus and whole thalamus were performed by manual tracing. The level of AI development was quantitatively defined as the maximal anterior-to-posterior length of the AI.

RESULTS

Schizophrenia patients had significantly smaller volumes of bilateral MDN. AI ratings were twice as high in women than in men among the control subjects; however, no gender difference emerged in the schizophrenia group due to reduced ratings in female patients. No significant correlation was found between MDN volumes and AI ratings among both groups.

CONCLUSIONS

These results provide evidence of volume reduction of the MDN, and female-specific underdevelopment of the AI in schizophrenia. As we did not demonstrate a relationship between MDN volume and AI ratings, it is suggested that these two measures of medial thalamic abnormality are manifestations of different neuropathological processes in schizophrenia patients.

Association between absence of the adhesio interthalamica and amygdala volume in schizophrenia

Abnormal neurodevelopment in midline structures such as the adhesio interthalamica (AI) has been reported in schizophrenia, but not consistently replicated. We investigated the prevalence and anterior-posterior length of the AI in 62 schizophrenia patients (32 males, 30 females) and 63 healthy controls (35 males, 28 females) using magnetic resonance imaging. We also explored the relation between the AI and volumetric measurements for the third ventricle, medial temporal structures (amygdala, hippocampus, and parahippocampal gyrus), superior temporal sub-regions, and frontal lobe regions (prefrontal area and anterior cingulate gyrus). The AI was absent in 24.2% (15/62) of the schizophrenia patients and in 9.5% (6/63) of the controls, showing a significant group difference. For the length of the AI, schizophrenia patients had a shorter AI than controls, and males had a shorter AI than females. The subjects without an AI had a significantly larger third ventricle and smaller parahippocampal gyrus than the subjects with an AI for both groups. We found a significant diagnosis-by-AI interaction for the amygdala. The schizophrenia patients without an AI had a smaller bilateral amygdala than those with an AI, whereas the AI was not associated with the volume of the amygdala in the control subjects. These findings suggest that the absence of AI in schizophrenia could be a marker of developmental abnormalities in the neural network including the thalamus and connected amygdaloid regions, which may play an important role in the pathogenesis of schizophrenia.

Investigation of a possible diencephalic pathology in schizophrenia

Absence of the adhesio interthalamica (AI) in schizophrenic first episode patients is suggestive for another marker of early developmental neuropathologic changes. Moreover, findings suggest that schizophrenic patients without AI are characterised by more severe negative symptoms. The study aims to investigate the presence vs. absence of AI in relation to brain measurements and clinical features. Presence or absence of AI and volumetric brain measurements were assessed in 50 patients with schizophrenia and 50 matched controls. No differences in the incidence of AI were found between the groups. Patients without AI revealed a strong trend towards a larger third ventricle and significantly higher scores for negative symptoms. Interestingly, the subgroup of healthy controls without AI also had larger third ventricles. The absence of AI may represent another early developmental marker of cerebral malformation in a clinical subgroup of schizophrenic patients.