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Neuroimaging databases for neuro‐psychiatric disorders enable researchers to implement data‐driven research approaches by providing access to rich data that can be used to study disease, build and validate machine learning models, and even redefine disease spectra. The importance of sharing large, multi‐center, multi‐disorder databases has gradually been recognized in order to truly translate brain imaging knowledge into real‐world clinical practice. Here, we review MRI databases that share data globally to serve multiple psychiatric or neurological disorders. We found 42 datasets consisting of 23,293 samples from patients with psychiatry and neurological disorders and healthy controls; 1245 samples from mood disorders (major depressive disorder and bipolar disorder), 2015 samples from developmental disorders (autism spectrum disorder, attention‐deficit hyperactivity disorder), 675 samples from schizophrenia, 1194 samples from Parkinson's disease, 5865 samples from dementia (including Alzheimer's disease), We recognize that large, multi‐center databases should include governance processes that allow data to be shared across national boundaries. Addressing technical and regulatory issues of existing databases can lead to better design and implementation and improve data access for the research community. The current trend toward the development of shareable MRI databases will contribute to a better understanding of the pathophysiology, diagnosis and assessment, and development of early interventions for neuropsychiatric disorders. [ABSTRACT FROM AUTHOR]

Increased excitatory neuronal tones have been implicated in autism, but its mechanism remains elusive. The amplified glutamate signals may arise from enhanced glutamatergic circuits, which can be affected by astrocyte activation and suppressive signaling of dopamine neurotransmission. We tested this hypothesis using magnetic resonance spectroscopy and positron emission tomography scan with 11C-SCH23390 for dopamine D1 receptors in the anterior cingulate cortex (ACC). We enrolled 18 male adults with high-functioning autism and 20 typically developed (TD) male subjects. The autism group showed elevated glutamate, glutamine, and myo-inositol (mI) levels compared with the TD group (p = 0.045, p = 0.044, p = 0.030, respectively) and a positive correlation between glutamine and mI levels in the ACC (r = 0.54, p = 0.020). In autism and TD groups, ACC D1 receptor radioligand binding was negatively correlated with ACC glutamine levels (r = − 0.55, p = 0.022; r = − 0.58, p = 0.008, respectively). The enhanced glutamate-glutamine metabolism might be due to astroglial activation and the consequent reinforcement of glutamine synthesis in autistic brains. Glutamine synthesis could underly the physiological inhibitory control of dopaminergic D1 receptor signals. Our findings suggest a high neuron excitation-inhibition ratio with astrocytic activation in the etiology of autism. [ABSTRACT FROM AUTHOR]

Aim: Increasing evidence suggests that psychiatric disorders are linked to alterations in the mesocorticolimbic dopamine‐related circuits. However, the common and disease‐specific alterations remain to be examined in schizophrenia (SCZ), major depressive disorder (MDD), and autism spectrum disorder (ASD). Thus, this study aimed to examine common and disease‐specific features related to mesocorticolimbic circuits. Methods: This study included 555 participants from four institutes with five scanners: 140 individuals with SCZ (45.0% female), 127 individuals with MDD (44.9%), 119 individuals with ASD (15.1%), and 169 healthy controls (HC) (34.9%). All participants underwent resting‐state functional magnetic resonance imaging. A parametric empirical Bayes approach was adopted to compare estimated effective connectivity among groups. Intrinsic effective connectivity focusing on the mesocorticolimbic dopamine‐related circuits including the ventral tegmental area (VTA), shell and core parts of the nucleus accumbens (NAc), and medial prefrontal cortex (mPFC) were examined using a dynamic causal modeling analysis across these psychiatric disorders. Results: The excitatory shell‐to‐core connectivity was greater in all patients than in the HC group. The inhibitory shell‐to‐VTA and shell‐to‐mPFC connectivities were greater in the ASD group than in the HC, MDD, and SCZ groups. Furthermore, the VTA‐to‐core and VTA‐to‐shell connectivities were excitatory in the ASD group, while those connections were inhibitory in the HC, MDD, and SCZ groups. Conclusion: Impaired signaling in the mesocorticolimbic dopamine‐related circuits could be an underlying neuropathogenesis of various psychiatric disorders. These findings will improve the understanding of unique neural alternations of each disorder and will facilitate identification of effective therapeutic targets. [ABSTRACT FROM AUTHOR]

People make flexible decisions across a wide range of contexts to resolve social or moral conflicts. Individuals with autism spectrum disorder (ASD) frequently report difficulties in such behaviors, which hinders the flexibility in changing strategies during daily activities or adjustment of perspective during communication. However, the underlying mechanisms of this issue are insufficiently understood. This study aimed to investigate decision flexibility in ASD using a functional magnetic resonance imaging task that involved recognizing and resolving two types of moral dilemmas: cost–benefit analysis (CBA) and mitigating inevitable misconducts (MIM). The CBA session assessed the participants' pitting of result-oriented outcomes against distressful harmful actions, whereas the MIM session assessed their pitting of the extenuation of a criminal sentence against a sympathetic situation of defendants suffering from violence or disease. The behavioral outcome in CBA-related flexibility was significantly lower in the ASD group compared to that of the typical development group. In the corresponding CBA contrast, activation in the left inferior frontal gyrus was lower in the ASD group. Meanwhile, in the MIM-related flexibility, there were no significant group differences in behavioral outcome or brain activity. Our findings add to our understanding of flexible decision-making in ASD. [ABSTRACT FROM AUTHOR]

The neuromodulatory effects of brain stimulation therapies notably involving repetitive transcranial magnetic stimulation (rTMS) on nocturnal sleep, which is critically disturbed in major depression and other neuropsychiatric disorders, remain largely undetermined. We have previously reported in major depression patients that prefrontal rTMS sessions enhanced their slow wave activity (SWA) power, but not their sigma power which is related to sleep spindle activity, for electrodes located nearby the stimulation site. In the present study, we focused on measuring the spindle density to investigate cumulative effects of prefrontal rTMS sessions on the sleep spindle activity. Fourteen male inpatients diagnosed with medication-resistant unipolar or bipolar depression were recruited and subjected to 10 daily rTMS sessions targeting the left dorsolateral prefrontal cortex (DLPFC). All-night polysomnography (PSG) data was acquired at four time points: Adaptation, Baseline, Post-1 (follow-up after the fifth rTMS session), and Post-2 (follow-up after the tenth rTMS session). Clinical and cognitive evaluations were longitudinally performed at Baseline, Post-1, and Post-2 time points to explore associations with the spindle density changes. The PSG data from 12 of 14 patients was analyzed to identify sleep spindles across the sleep stages II–IV at four electrode sites: F3 (frontal spindle near the stimulation site), F4 (contralateral homologous frontal region), P3 (parietal spindle in the hemisphere ipsilateral to the stimulation site), and P4 (contralateral parietal region). Statistical analysis by two-way ANOVA revealed that spindle density at F3 increased at Post-1 but decreased at Post-2 time points. Moreover, the local and transient increase of spindle density at F3 was associated with the previously reported SWA power increase at F3, possibly reflecting a shared mechanism of thalamocortical synchronization locally enhanced by diurnal prefrontal rTMS sessions. Clinical and cognitive correlations were not observed in this dataset. These findings suggest that diurnal rTMS sessions transiently modulate nocturnal sleep spindle activity at the stimulation site, although clinical and cognitive effects of the local changes warrant further investigation. [ABSTRACT FROM AUTHOR]

People are often influenced by past costs in their current decision-making, thus succumbing to a well-known bias recognized as the sunk cost effect. A recent study showed that the sunk cost effect is attenuated in individuals with autism spectrum disorder (ASD). However, the study only addressed one situation of utilization decision by focusing on the choice between similar attractive alternatives with different levels of sunk costs. Thus, it remains unclear how individuals with ASD behave under sunk costs in different types of decision situations, particularly progress decisions, in which the decision-maker allocates additional resources to an initially chosen alternative. The sunk cost effect in progress decisions was estimated using an economic task designed to assess the effect of the past investments on current decision-making. Twenty-four individuals with ASD and 21 age-, sex-, smoking status-, education-, and intelligence quotient-level-matched typical development (TD) subjects were evaluated. The TD participants were more willing to make the second incremental investment if a previous investment was made, indicating that their decisions were influenced by sunk costs. However, unlike the TD group, the rates of investments were not significantly increased after prior investments in the ASD group. The results agree with the previous evidence of a reduced sensitivity to context stimuli in individuals with ASD and help us obtain a broader picture of the impact of sunk costs on their decision-making. Our findings will contribute to a better understanding of ASD and may be useful in addressing practical implications of their socioeconomic behavior. [ABSTRACT FROM AUTHOR]

Intergroup bias, which is the tendency to behave more positively toward an in‐group member than toward an out‐group member, is pervasive in real life. In particular, intergroup bias in trust decisions substantially influences multiple areas of life and thus better understanding of this tendency can provide significant insights into human social behavior. Although previous functional magnetic resonance imaging studies showed the involvement of the right temporoparietal junction (TPJ) in intergroup trust bias, a causal relationship between the two has rarely been explored. By combining repetitive transcranial magnetic stimulation and a newly developed trust game task, we investigated the causal role of the right TPJ in intergroup bias in trust decisions. In the trust game task, the counterpart's group membership (in‐group or out‐group) and reciprocity were manipulated. We applied either neuronavigated inhibitory continuous theta burst stimulation (cTBS) or sham stimulation over the right TPJ before performing the trust game task in healthy volunteers. After the sham stimulation, the participants' degrees of investments with in‐group members were significantly higher than those with out‐group members. However, after cTBS to the right TPJ, this difference was not observed. The current results extend previous findings by showing that the causal roles of the right TPJ can be observed in intergroup bias in trust decisions. Our findings add to our understanding of the mechanisms of human social behavior. [ABSTRACT FROM AUTHOR]

Endophenotype refers to a measurable and heritable component between genetics and diagnosis, and the same endophenotype is present in both individuals with a diagnosis and their unaffected siblings. Determination of the neural correlates of an endophenotype and diagnosis is important in autism spectrum disorder (ASD). However, prior studies enrolling individuals with ASD and their unaffected siblings have generally included only one group of typically developing (TD) subjects; they have not accounted for differences between TD siblings. Thus, they could not differentiate the neural correlates for endophenotype from the clinical diagnosis. In this context, we enrolled pairs of siblings with an ASD endophenotype (individuals with ASD and their unaffected siblings) and pairs of siblings without this endophenotype (pairs of TD siblings). Using resting-state functional MRI, we first aimed to identify an endophenotype pattern consisting of multiple functional connections (FCs) then examined the neural correlates of FCs for ASD diagnosis, controlling for differences between TD siblings. Sparse logistic regression successfully classified subjects as to the endophenotype (area under the curve = 0.78, classification accuracy = 75%). Then, a bootstrapping approach controlling for differences between TD siblings revealed that an FC between the right middle temporal gyrus and right anterior cingulate cortex was substantially different between individuals with ASD and their unaffected siblings, suggesting that this FC may be a neural correlate for the diagnosis, while the other FCs represent the endophenotype. The current findings suggest that an ASD endophenotype pattern exists in FCs, and a neural correlate for ASD diagnosis is dissociable from this endophenotype. (250 words). [ABSTRACT FROM AUTHOR]

Individuals with autism spectrum conditions (ASCs) often experience difficulty and confusion in acknowledging others' perspectives and arguably exhibit egocentricity. However, whether this egocentricity necessarily results in selfish behavior during social situations remains a matter of debate. To study this relationship, we used computerized visuospatial perspective‐taking task (VPT) and social‐discounting task (SDT), derived from cognitive psychology and behavioral economics, and examined egocentric and other‐oriented judgments in participants with ASCs (mean age 29.0 ± 4.2 years) and a group of matched typically developing (TD) controls (30.8 ± 8.5). The response time in VPT showed altered perspective‐taking in the ASCs group compared with the TD group that involved in enhanced self‐other intrusion and condition‐insensitive response. Regardless of self/other perspective judgments, responses were relatively slower and consistent in duration in the ASCs group compared with the TD group. Social discounting was attenuated rather than steep discounting in the ASCs group. Their discounting was comparatively more consistent, irrespective of the task condition (i.e., self‐other closeness‐level). In effect, ASCs group exhibited more generous decisions than the TD group in this task. Finally, those with more egocentric perspective intrusion in VPT paradoxically showed more generous behaviors in SDT in the ASCs group. Our findings suggest that having ASCs does not always exhibit selfish behavior during interpersonal communication. Reduced flexibility in distinguishing self/other perspective and shifting decision‐rules might account for this unique relationship between egocentricity and apparently generous behaviors. These results extend the recent suggestion that more careful attention should be paid to the idea of egocentricity in individuals with ASCs. Autism Res2019. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. Lay Summary: We aimed to examine whether seeing the world from another person's point of view and being generous toward other people are related in autistic and nonautistic people. We used a visual perspective‐taking task and a social task in which individuals made decisions about how to divide a sum of money with others. Our results suggest that being autistic does not always make someone bad at seeing the world from another's viewpoint, and that autistic people may make fairer social decisions toward unfamiliar people because of lower bias. [ABSTRACT FROM AUTHOR]

Aim: Prior structural magnetic resonance imaging studies demonstrated atypical gray matter characteristics in siblings of individuals with autism spectrum disorder (ASD). However, they did not clarify which aspect of gray matter is related to the endophenotype (i.e., genetic vulnerability) of ASD. Further, because they did not enroll siblings of typically developing (TD) people, they may have underestimated the difference between individuals with ASD and their unaffected siblings. The current study aimed to address these gaps. Methods: We recruited 30 pairs of adult male siblings (15 pairs with an ASD endophenotype and 15 pairs without) and focused on four gray matter parameters: cortical volume and three surface‐based parameters (cortical thickness, fractal dimension, and sulcal depth [SD]). First, we sought to identify a pattern of an ASD endophenotype, comparing the four parameters. Then, we compared individuals with ASD and their unaffected siblings in the cortical parameters to identify neural correlates for the clinical diagnosis accounting for the difference between TD siblings. Results: A sparse logistic regression with a leave‐one‐pair‐out cross‐validation showed the SD as having the highest accuracy for the identification of an ASD endophenotype (73.3%) compared with the other three parameters. A bootstrapping analysis accounting for the difference in the SD between TD siblings showed a significantly large difference between individuals with ASD and their unaffected siblings in six out of 68 regions of interest. Conclusion: This proof‐of‐concept study suggests that an ASD endophenotype emerges in the SD and that neural bases for ASD diagnosis can be discerned from the endophenotype when accounting for the difference between TD siblings. [ABSTRACT FROM AUTHOR]

The sunk cost effect, an interesting and well-known decision bias, is pervasive in real life and has been studied in various disciplines. In this study, we modified a task exemplifying the sunk cost effect and used it to evaluate this behavior in individuals with autism spectrum disorder (ASD). The control group exhibited a typical sunk cost effect in our task. We found that the sunk cost effect was lower in the ASD group than in the control group. The results agree with previous evidence of reduced sensitivity to context stimuli in individuals with ASD and extend this finding to the context of the sunk cost effect. Our findings are useful in addressing the practical implications on their socioeconomic behavior. [ABSTRACT FROM AUTHOR]

Since prior diffusion tensor imaging (DTI) studies reported no significant differences in white matter organizations between individuals with autism spectrum disorder (ASD) and their unaffected siblings, the neural correlates for developing a clinical diagnosis among people with endophenotypes remain undetermined. We obtained DTI data from a total of 60 participants consisting of 30 people with endophenotypes and 30 people without. We first followed a conventional approach by comparing individuals with ASD and their unaffected siblings. Using region-of-interest approach, we then performed bootstrapping to examine whether the differences in white matter organizations between individuals with ASD and their unaffected siblings were substantially large, considering the distribution of differences between typically developing (TD) siblings. Conventional approaches revealed no significant differences in white matter organizations between individuals with ASD and their unaffected siblings. Bootstrapping revealed a significantly large difference in axial diffusivity in the left stria terminalis between individuals with ASD and their unaffected siblings after accounting for the distribution of differences in axial diffusivity among TD siblings (99.998 percentile). The results remained significant after controlling for multiple comparisons with Bonferroni method. We assumed that one aspect of this tract was associated with the development of a clinical diagnosis. [ABSTRACT FROM AUTHOR]

A 3.2-MP four-directional polarization image sensor with air-gap wire-grid polarizer is described. The image sensor was fabricated using a wafer process and incorporates back-illumination and an antireflection layer to minimize optical flaring and ghosting problems. In testing, the sensor achieved a polarization transmittance of 63.3% and an extinction ratio of 85 at 550 nm, thereby outperforming conventional polarization sensors. The proposed sensor also exhibited good oblique-incidence characteristics, even with small polarization pixels of $2.5~\mu \text{m}$. Based on these results, the proposed image sensor is suitable for various megapixel fusion-imaging applications, such as reducing surface reflections, highly accurate depth mapping, and condition-robust surveillance. [ABSTRACT FROM AUTHOR]

In interactive social situations, it is often crucial to be able to take another person's perspective when evaluating one's own or another person's specific trait; individuals with autism spectrum disorder (ASD) critically lack this social skill. To examine how perspective-dependent self- and other-evaluation processes modulate functional connectivity in ASD, we conducted a functional magnetic resonance imaging study in which 26 high-functioning adults with ASD and 24 typically developed (TD) controls were asked to decide whether an adjective describing a personality trait correctly described the participant himself/herself ("self") or the participant's mother ("other") by taking either the first (1P) or third person (3P) perspective. We observed that functional connectivity between the left sensorimotor cortex and the left middle cingulate cortex was enhanced in TD control individuals taking the 3P perspective, this enhancement was significantly reduced in ASD, and the degree of reduction was significantly correlated with the severity of autistic traits. Furthermore, the self-reference effect on functional connectivity between the left inferior frontal cortex and frontopolar cortices was significantly enhanced in TD control individuals taking the 3P perspective, whereas such effect was reversed in ASD. These findings indicate altered effects of perspective on the functional connectivity, which may underlie the deficits in social interaction and communication observed in individuals with ASD. [ABSTRACT FROM AUTHOR]

Aim Repetitive transcranial magnetic stimulation (rTMS) has been applied as a treatment for patients with treatment-resistant depression in recent years, and a large body of evidence has demonstrated its therapeutic efficacy through stimulating neuronal plasticity. The aim of this study was to investigate structural alterations in the hippocampus (HIPP) and amygdala (AM) following conventional rTMS in patients with depression. Methods Twenty-eight patients with depression underwent 10 daily 20-Hz left prefrontal rTMS over 2 weeks. The left dorsolateral prefrontal cortex (DLPFC) was identified using magnetic resonance imaging-guided neuronavigation prior to stimulation. Magnetic resonance imaging scans were obtained at baseline and after the completion of rTMS sessions. The therapeutic effects of rTMS were evaluated with the 17-item Hamilton Depression Rating Scale (HAM-D17), and the volumes of the HIPP and AM were measured by a manual tracing method. Results Statistical analyses revealed a significant volume increase in the left HIPP (+3.4%) after rTMS but no significant volume change in the AM. No correlation was found between the left HIPP volume increase and clinical improvement, as measured by the HAM-D17. Conclusion The present study demonstrated that conventional left prefrontal rTMS increases the HIPP volume in the stimulated side, indicating a remote neuroplastic effect through the cingulum bundle. [ABSTRACT FROM AUTHOR]

Although the ability to make optimal decisions under uncertainty is an integral part of everyday life, individuals with autism spectrum disorder (ASD) frequently report that they experience difficulties with this skill. In behavioral economics, researchers distinguish two types of uncertainty to understand decision-making in this setting: risk (known probabilities) and ambiguity (unknown probabilities). However, it remains unclear how individuals with ASD behave under risk and ambiguity, despite growing evidence of their altered decision-making under uncertainty. We therefore extended previous research by studying the attitudes of those with ASD toward risk and ambiguity in both positive and negative contexts (i.e., gain and loss). In gain contexts, no significant difference was observed between the groups in risk attitudes, but ambiguity aversion was attenuated in ASD. In loss contexts, ambiguity attitudes did not significantly differ between the groups, but the ASD participants were less risk-seeking compared with the controls. In addition, insensitivity to the context change under risk and ambiguity in ASD was both significantly associated with poor social skills. These results improve our understanding of altered decision-making under uncertainty by disentangling the attitudes toward risk and ambiguity in ASD individuals. Applying behavioral economic tools may provide insights into the mechanisms underlying behavioral disturbances in ASD. [ABSTRACT FROM AUTHOR]

Aim Numerous reports have described differences in the distribution of orbitofrontal cortex ( OFC) sulcogyral patterns between patients with schizophrenia ( SZ patients) and healthy controls ( HC). Alterations in OFC morphology are also observed in those at high risk for developing SZ and in first-episode SZ, suggesting that genetic associations may be extant in determining OFC sulcogyral patterns. We investigated the association between single nucleotide polymorphisms ( SNP) in NRG1 and OFC sulcogyral patterns. Methods A total of 59 Japanese patients diagnosed with SZ and 60 HC were scanned on a 1.5-T magnet. Patients were also assessed clinically. OFC sulcogyral patterns were evaluated for each participant, and genotyping was performed for four SNP in NRG1 ( SNP8NRG243177, SNP8NRG221533, SNP8NRG241930, and rs1081062 ). Results There were significant differences in the distribution of OFC sulcogyral patterns between SZ patients and HC (χ2 = 6.52, P = 0.038). SZ patients showed an increase in the frequency of Type III expression, which was associated with an earlier age of disease onset (β = −0.302, F = 4.948, P = 0.030). Although no difference was found in genotype frequencies between SZ patients and HC, an NRG1 SNP, SNP8NRG243177, was associated with Type II expression in SZ patients (β = 0.237, F = 4.120, P = 0.047). Conclusion Our results suggest that OFC sulcogyral pattern formation in schizophrenia may be associated with NRG1 allele frequency, which is closely related to neurodevelopment. [ABSTRACT FROM AUTHOR]

Attentional control is a key function of working memory that is hypothesized to play an important role in psychometric intelligence. To test the neuropsychological underpinnings of this hypothesis, we examined full-scale IQ, as measured by the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III), and attentional control, as measured by Trails B response time and Wisconsin Card Sorting (WCS) test perseverative errors in 78 healthy participants, 25 of whom also had available magnetic resonance imaging (MRI) gray matter volume studies of the orbital frontal cortex (OFC) parcellated into three regions: gyrus rectus, middle orbital gyrus, and lateral orbital gyrus. Hierarchical regression indicated that Trails B response time specifically explained 15.13% to 19.18% of the variation in IQ and WCS perseverative errors accounted for an additional 8.12% to 11.29% of the variance. Full-scale IQ correlated very strongly with right middle orbital gyrus gray matter volume (r=0.610, p=0.002), as did Trails B response time with left middle orbital gyrus gray matter volume (r=-0.608, p=0.003). Trails B response time and right middle orbital gyrus gray matter volume jointly accounted for approximately 32.95% to 54.82% of the variance in IQ scores. These results provided evidence of the unique contributions of attentional control and OFC gray matter to intelligence. [ABSTRACT FROM AUTHOR]

Suberin is a complex polymer composed of aliphatic and phenolic compounds. It is a constituent of apoplastic plant interfaces. In many plant species, including rice ( Oryza sativa), the hypodermis in the outer part of roots forms a suberized cell wall (the Casparian strip and/or suberin lamellae), which inhibits the flow of water and ions and protects against pathogens. To date, there is no genetic evidence that suberin forms an apoplastic transport barrier in the hypodermis. We discovered that a rice reduced culm number1 ( rcn1) mutant could not develop roots longer than 100 mm in waterlogged soil. The mutated gene encoded an ATP-binding cassette (ABC) transporter named RCN1/OsABCG5. RCN1/OsABCG5 gene expression in the wild type was increased in most hypodermal and some endodermal roots cells under stagnant deoxygenated conditions. A GFP-RCN1/OsABCG5 fusion protein localized at the plasma membrane of the wild type. Under stagnant deoxygenated conditions, well suberized hypodermis developed in wild types but not in rcn1 mutants. Under stagnant deoxygenated conditions, apoplastic tracers (periodic acid and berberine) were blocked at the hypodermis in the wild type but not in rcn1, indicating that the apoplastic barrier in the mutant was impaired. The amount of the major aliphatic suberin monomers originating from C28 and C30 fatty acids or ω-OH fatty acids was much lower in rcn1 than in the wild type. These findings suggest that RCN1/OsABCG5 has a role in the suberization of the hypodermis of rice roots, which contributes to formation of the apoplastic barrier. [ABSTRACT FROM AUTHOR]

Recent functional magnetic resonance imaging (fMRI) studies on autism spectrum condition (ASC) have identified dysfunctions in specific brain networks involved in social and non-social cognition that persist into adulthood. Although increasing numbers of fMRI studies have revealed atypical functional connectivity in the adult ASC brain, such functional alterations at the network level have not yet been fully characterized within the recently developed graph-theoretical framework. Here, we applied a graph-theoretical analysis to resting-state fMRI data acquired from 46 adults with ASC and 46 age- and gender-matched controls, to investigate the topological properties and organization of autistic brain network. Analyses of global metrics revealed that, relative to the controls, participants with ASC exhibited significant decreases in clustering coefficient and characteristic path length, indicating a shift towards randomized organization. Furthermore, analyses of local metrics revealed a significantly altered organization of the hub nodes in ASC, as shown by analyses of hub disruption indices using multiple local metrics and by a loss of “hubness” in several nodes (e.g., the bilateral superior temporal sulcus, right dorsolateral prefrontal cortex, and precuneus) that are critical for social and non-social cognitive functions. In particular, local metrics of the anterior cingulate cortex consistently showed significant negative correlations with the Autism-Spectrum Quotient score. Our results demonstrate altered patterns of global and local topological properties that may underlie impaired social and non-social cognition in ASC. [ABSTRACT FROM AUTHOR]

We examined social cognition in a sample of healthy participants who had prior magnetic resonance imaging (MRI) gray matter volume studies of the orbital frontal cortex (OFC) that was parcellated into three regions: gyrus rectus, middle orbital gyrus and lateral orbital gyrus. These subjects also completed a self-report measure of Machiavelli personality traits, along with psychometric tests of social comprehension and declarative episodic memory, all of which we used as proxy measures to examine various features of social cognition. The data pointed to distinct functional–anatomical relationships highlighted by strong correlations of left lateral orbital gyrus and Machiavellian scores and right middle orbital gyrus with social comprehension and declarative episodic memory. In addition, hierarchical regression analyses revealed statistical evidence of a double dissociation between Machiavellian scores and left lateral orbital gyrus on one hand, and social comprehension with right middle orbital gyrus, on the other hand. To our knowledge, these findings are the first to show evidence linking normal variation in OFC subregions and different aspects of social cognition. [ABSTRACT FROM PUBLISHER]

We examined variability in performance on widely-used neuropsychological Wechsler tests of intelligence and memory in a large sample of persons with chronic schizophrenia, a subset of whom had also undergone prior studies of magnetic resonance imaging (MRI) of the orbital frontal cortex (OFC) gray matter and diffusion tensor imaging (DTI) of the cingulum bundle (CB) and the uncinate fasiculus (UF) white matter. In comparison to controls, persons with schizophrenia showed lower scores across neuropsychological tests, with most pronounced drops in processing speed and immediate memory, in relation to oral reading. For patients, greater declines in intelligence and memory each correlated with reduced CB white matter fractional anisotropy and reduced OFC gray matter, respectively. However, only memory decline correlated with severity of negative symptoms. Taken together, these data raise the intriguing question as to whether communication and motivational deficits expressed in negative symptoms may contribute to the relationship of auditory memory decline and OFC volume observed in this patient sample. [ABSTRACT FROM AUTHOR]

Aim: The sulcogyral pattern of the orbitofrontal cortex (OFC) is characterized by a remarkable inter-individual variability that likely reflects neurobehavioral traits and genetic aspects of neurodevelopment. The aim of the present study was to evaluate the OFC sulcogyral pattern of patients with schizophrenia (SZ) and healthy controls (HC) to determine group differences in OFC sulcogyral pattern as well as gender differences between groups. Methods: Forty-seven SZ patients (M/F, 23/24) and forty-seven HC (M/F, 17/30), matched on age and gender, were analyzed using magnetic resonance imaging. The sulcogyral pattern was classified into type I, II, or III based on the guidelines set by Chiavaras and Petrides in a previous paper. Chi-squared analysis was used to investigate group and gender differences in the sulcogyral pattern distribution, and categorical regression was used to explore clinical correlations. Results: The distribution of OFC sulcogyral pattern in HC replicated the results found in the previous study (left, χ2 = 0.02, P = 0.989; right, χ2 = 0.97, P = 0.616), in that there were no gender differences. Moreover, the distribution in SZ-M was in accordance with that in the previous study (left, χ2 = 1.59, P = 0.451; right, χ2 = 0.14, P = 0.933). Additionally, within SZ-M, patients with the type III pattern had a higher total positive and negative syndrome scale score (β = 0.902, F = 14.75, P = 0.001). In contrast, the distribution in the right hemisphere in the SZ-F group differed significantly from that observed in SZ-M (χ2 = 6.017, P = 0.046), but did not differ from HC (χ2 = 2.557, P = 0.110). Conclusion: OFC sulcogyral pattern is altered in SZ-M but not in SZ-F, possibly reflecting gender differences in early neurodevelopment. [ABSTRACT FROM AUTHOR]

Although recent studies suggest abnormalities of the cerebral cortex, limbic structures, and brain stem regions in panic disorder (PD), the extent to which the midbrain is associated with PD pathophysiology is unclear. The aim of this study was to investigate structural abnormalities of the midbrain using magnetic resonance imaging and to determine if there is a clinical correlation between midbrain volume and clinical measurements in patients with PD. Thirty-eight patients with PD (PD group) and 38 healthy controls (HC group) participated in this study. The midbrain was measured with a manual tracing method with high spatial resolution magnetic resonance imaging. The Panic Disorder Severity Scale and Global Assessment of Functioning were used to examine the correlation between volume abnormality and clinical symptoms and functioning in the PD group. Relative midbrain volume was larger in the PD group than in the HC group. The relative volume of the dorsal midbrain was larger in the PD group, while the volume of the ventral midbrain was not. We found a significant positive correlation between relative dorsal midbrain volume and total Panic Disorder Severity Scale score, and a significant negative correlation between relative dorsal midbrain volume and Global Assessment of Functioning score in the PD group. Our findings suggest that the dorsal midbrain is associated with PD pathophysiology. The midbrain volume increase may reflect PD severity. [ABSTRACT FROM AUTHOR]

Aims: The posterior region of the orbitofrontal cortex (OFC), which forms its sulcogyral pattern during neurodevelopment, receives multisensory inputs. The purpose of the present study was to assess the relationship between posterior OFC sulcogyral pattern and OFC volume difference in patients with panic disorder. Methods: The anatomical pattern of the posterior orbital sulcus (POS) was classified into three subtypes (absent POS, single POS, double POS) using 3-D high-spatial resolution magnetic resonance images obtained from 28 patients with panic disorder and 28 age- and gender-matched healthy controls. Optimized voxel-based morphometry (VBM) was performed to assess OFC volume differences between the two groups by subtype. Categorical regression analysis was applied to examine the association of POS subtypes with State–Trait Anxiety Inventory and Revised Neuroticism-Extraversion-Openness Personality Inventory scores. Results: No significant difference was found in POS subtype distribution between control subjects and patients with panic disorder. VBM, however, indicated volume reduction in the right posterior–medial OFC region in panic disorder patients with absent POS and single POS. Single POS was positively associated with Trait-Anxiety (β = 0.446, F = 6.409, P = 0.020), and absent POS was negatively associated with Trait-Anxiety (β = −0.394, F = 5.341, P = 0.032) and Neuroticism trait (β = −0.492, F = 6.989, P = 0.017). Conclusions: POS subtypes may be relevant to volume reduction in OFC and the anxiety trait in patients with panic disorder. These findings suggest that volume reduction in OFC in panic disorder may be associated with neurodevelopment. [ABSTRACT FROM AUTHOR]

Aims: Anxiety a core feature of panic disorder, is linked to function of the amygdala. Volume alterations in the brain of patients with panic disorder have previously been reported, but there has been no report of amygdala volume association with anxiety. Methods: Volumes of hippocampus and amygdala were manually measured using magnetic resonance imaging obtained from 27 patients with panic disorder and 30 healthy comparison subjects. In addition the amygdala was focused on, applying small volume correction to optimized voxel-based morphometry (VBM). State–Trait Anxiety Inventory and the NEO Personality Inventory Revised were also used to evaluate anxiety. Results: Amygdala volumes in both hemispheres were significantly smaller in patients with panic disorder compared with control subjects (left: t = −2.248, d.f. = 55, P = 0.029; right: t = −2.892, d.f. = 55, P = 0.005). VBM showed that structural alteration in the panic disorder group occurred on the corticomedial nuclear group within the right amygdala (coordinates [x,y,z (mm)]: [26,−6,−16], Z score = 3.92, family-wise error-corrected P = 0.002). The state anxiety was negatively correlated with the left amygdala volume in patients with panic disorder (r = −0.545, P = 0.016). Conclusions: These findings suggested that the smaller volume of the amygdala may be associated with anxiety in panic disorder. Of note, the smaller subregion in the amygdala estimated on VBM could correspond to the corticomedial nuclear group including the central nucleus, which may play a crucial role in panic attack. [ABSTRACT FROM AUTHOR]

Aim: Recent neuroimaging studies have suggested that the anterior cingulate cortex (ACC) has an important role in the pathology of panic disorder. Despite numerous functional neuroimaging studies that have elucidated the strong relationship between functional abnormalities of the ACC and panic disorder and its symptoms and response to emotional tasks associated with panic disorder, there has been no study showing volumetric changes of the ACC or its subregions. Methods: To clarify the structural abnormalities of ACC and its subregions, the combination of region of interest (ROI) and optimized voxel-based morphometry (VBM) methods were performed on 26 patients with panic disorder, and 26 age and sex-matched healthy subjects. In the ROI study, ACC was divided into four subregions: dorsal, rostral, subcallosal and subgenual ACC. Results: The results of the manually traced ROI volume comparison showed significant volume reduction in the right dorsal ACC. VBM also showed a volume reduction in the right dorsal as well as a part of the rostral ACC as a compound mass. Conclusions: Both manual ROI tracing and optimized VBM suggest a subregion-specific pattern of ACC volume deficit in panic disorder. In addition to functional abnormalities, these results suggest that structural abnormalities of the ACC contribute to the pathophysiology of panic disorder. [ABSTRACT FROM AUTHOR]

Orbitofrontal Cortex (OFC) structural abnormality in schizophrenia has not been well characterized, probably due to marked anatomical variability and lack of consistent definitions. We previously reported OFC sulcogyral pattern alteration and its associations with social disturbance in schizophrenia, but OFC volume associations with psychopathology and cognition have not been investigated. We compared chronically treated schizophrenia patients with healthy control (HC) subjects, using a novel, reliable parcellation of OFC subregions and their association with cognition, especially the Iowa Gambling Task (IGT), and with schizophrenic psychopathology including thought disorder. Twenty-four patients with schizophrenia and 25 age-matched HC subjects underwent MRI. OFC Regions of Interest (ROI) were manually delineated according to anatomical boundaries: Gyrus Rectus (GR); Middle Orbital Gyrus (MiOG); and Lateral Orbital Gyrus (LOG). The OFC sulcogyral pattern was also classified. Additionally, MiOG probability maps were created and compared between groups in a voxel-wise manner. Both groups underwent cognitive evaluations using the IGT, Wisconsin Card Sorting Test, and Trail Making Test (TMT). An 11% bilaterally smaller MiOG volume was observed in schizophrenia, compared with HC (F(1,47) = 17.4, P = 0.0001). GR and LOG did not differ, although GR showed a rightward asymmetry in both groups (F(1,47) = 19.2, P < 0.0001). The smaller MiOG volume was independent of the OFC sulcogyral pattern, which differed in schizophrenia and HC (chi2 = 12.49, P = 0.002). A comparison of MiOG probability maps suggested that the anterior heteromodal region was more affected in the schizophrenia group than the posterior paralimbic region. In the schizophrenia group, a smaller left MiOG was strongly associated with worse 'positive formal thought disorder' (r = -0.638, P = 0.001), and a smaller right MiOG with a longer duration of the illness (r = -0.618, P = 0.002). While schizophrenics showed poorer performance than HC in the IGT, performance was not correlated with OFC volume. However, within the HC group, the larger the right hemisphere MiOG volume, the better the performance in the IGT (r = 0.541, P = 0.005), and the larger the left hemisphere volume, the faster the switching attention performance for the TMT, Trails B (r = -0.608, P = 0.003). The present study, applying a new anatomical parcellation method, demonstrated a subregion-specific OFC grey matter volume deficit in patients with schizophrenia, which was independent of OFC sulcogyral pattern. This volume deficit was associated with a longer duration of illness and greater formal thought disorder. In HC the finding of a quantitative association between OFC volume and IGT performance constitutes, to our knowledge, the first report of this association. [ABSTRACT FROM AUTHOR]

The structural abnormality of planum temporale (PT), a part of the superior temporal heteromodal association cortex involved in auditory and language processing, has been implicated in the pathophysiology of schizophrenia. However, its relationship to clinical manifestations remains unclear. Magnetic resonance images were obtained from 17 right-handed Japanese men with schizophrenia and from 22 age-, handedness-, and parental socioeconomic-status-matched healthy Japanese men in order to manually evaluate grey matter volumes of Heschl’s gyrus (HG) and PT. Psychiatric symptoms were assessed using positive and negative syndrome scale among the patients. Compared with healthy participants, patients with schizophrenia were associated with a statistically significant PT grey matter volume reduction without left or right lateralization, whereas HG volume was preserved. Smaller right PT volume was significantly correlated with more severe delusional behaviour in the patients. Previous investigations have focused on smaller-than-normal left PT in the pathophysiology of schizophrenia; however, the present results suggest a possible role of the right PT, which is involved in social cognition such as understanding the intentions of others, in the production of psychotic experiences in patients with schizophrenia. [ABSTRACT FROM AUTHOR]

We introduce an algorithm for segmenting brain magnetic resonance (MR) images into anatomical compartments such as the major tissue classes and neuro-anatomical structures of the gray matter. The algorithm is guided by prior information represented within a tree structure. The tree mirrors the hierarchy of anatomical structures and the subtrees correspond to limited segmentation problems. The solution to each problem is estimated via a conventional classifier. Our algorithm can be adapted to a wide range of segmentation problems by modifying the tree structure or replacing the classifier. We evaluate the performance of our new segmentation approach by revisiting a previously published statistical group comparison between first-episode schizophrenia patients, first-episode affective psychosis patients, and comparison subjects. The original study is based on 50 MR volumes in which an expert identified the brain tissue classes as well as the superior temporal gyrus, amygdala, and hippocampus. We generate analogous segmentations using our new method and repeat the statistical group comparison. The results of our analysis are similar to the original findings, except for one structure (the left superior temporal gyrus) in which a trend-level statistical significance (p = 0.07) was observed instead of statistical significance. [ABSTRACT FROM AUTHOR]

The article discusses the study that determines the formation of smaller neocortical gray matter and larger sulcal cerebrospinal fluid volumes in neuroleptic-naive women with schizotypal personality disorder. According to the author, former studies reveal several structural brain abnormalities observed in men having schizotypal personality disorder. The authors aim to determine if same condition can be observed with women.

Abstract All-night recordings from subdural electrocorticographic (ECoG) electrodes on the human medial and basal temporal lobes were analysed to examine spindling activities during sleep. Subjects were three males and three females who were candidates for neurosurgical treatments of partial epilepsy. Subdural electrodes were attached to the medial and basal temporal lobe cortices, allowing ECoG and electroencephalogram from the scalp vertex (Cz EEG) to be recorded simultaneously during all night sleep. In one case, subdural electrodes were attached also on the parietal lobe. Fast Fourier transformation (FFT) analyses were performed on the ECoG and Cz EEG signals. No organized sleep spindles or sigma band (12–16 Hz) peaks in FFT power spectra were observed from the medial or basal temporal lobes of the non-epileptogenic hemispheres during non-rapid eye movement (NREM) sleep. In a case with parietal electrodes, organized spindle bursts were observed in parietal signals synchronized with Cz spindles. Although delta band (0.3–3 Hz) power from both the medial and basal temporal lobes fluctuated across each night as expected, sigma activity changed little. However, 14 Hz oscillatory bursts were observed in the medial basal temporal lobe of epileptogenic hemisphere in two cases and bilaterally in one case during not only NREM sleep but rapid eye movement (REM) sleep and wakefulness. From the present study we conclude that sleep spindle activities are absent in the medial and basal temporal lobes. Fourteen Hz oscillatory bursts observed from the medial or basal temporal lobe in some cases were not considered to be sleep spindles since they also appeared during REM sleep and wakefulness. These waveforms could have originated due to epileptic pathology, since they frequently appeared in epileptic regions. [ABSTRACT FROM AUTHOR]

Examines the use of magnetic resonance angiography (MR angiography) in a demented patient diagnosed with probable Alzheimer's disease in Tokyo, Japan. Efficacy of MR angiography in elucidating the locus of vascular pathology of dementia; Detection of latent angiography obliteration; Clarification of the cerebrovascular involvement of dementia.

Background: Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) have high rates of co-occurrence and share atypical behavioral characteristics, including sensory symptoms. The present diffusion tensor imaging (DTI) study was conducted to examine whether and how white matter alterations are observed in adult populations with developmental disorders (DD) and to determine how brain–sensory relationships are either shared between or distinct to ASD and ADHD. Methods: We collected DTI data from adult population with DD (a primary diagnosis of ASD: n = 105, ADHD: n = 55) as well as age- and sex-matched typically developing (TD) participants (n = 58). Voxel-wise fractional anisotropy (FA), mean diffusivity, axial diffusivity, and radial diffusivity (RD) were analyzed using tract-based spatial statistics. The severities of sensory symptoms were assessed using the Adolescent/Adult Sensory Profile (AASP). Results: Categorical analyses identified voxel clusters showing significant effects of DD on FA and RD in the posterior portion of the corpus callosum and its extension in the right hemisphere. Furthermore, regression analyses using the AASP scores revealed that slopes in relationships of FA or RD with the degree of sensory symptoms were parallel between the two DDs in large parts of the affected corpus callosum regions. A small but significant cluster did exist showing difference in association between an AASP subscale score and RD across ASD and ADHD. Limitations: Wide age range of the participants may be oversimplified. Conclusions: These results indicate that white matter alteration and their relationships to sensory symptoms are largely shared between ASD and ADHD, with localized abnormalities showing significant between-diagnosis differences within DD. [ABSTRACT FROM AUTHOR]