Smaller superior temporal gyrus volume specificity in schizotypal personality disorder

Multiple genes encoding mitochondrial ribosomes are downregulated in brain and blood samples of individuals with schizophrenia

OBJECTIVES

Schizophrenia is a chronic, debilitating mental disorder whose pathophysiology is complex and not fully understood. Numerous studies suggest mitochondrial dysfunction may contribute to the development of schizophrenia. While mitochondrial ribosomes (mitoribosomes) are essential for proper mitochondrial functioning, their gene expression levels have not been studied yet in schizophrenia.

METHODS

We performed a systematic meta-analysis of the expression of 81 mitoribosomes subunits encoding genes, integrating ten brain samples datasets of patients with schizophrenia compared to healthy controls (overall 422 samples, 211 schizophrenia, and 211 controls). We also performed a meta-analysis of their expression in blood, integrating two blood sample datasets (overall 90 samples, 53 schizophrenia, and 37 controls).

RESULTS

Multiple mitoribosomes subunits were significantly downregulated in brain samples (18 genes) and in blood samples (11 genes) of individuals with schizophrenia, where two showed significant downregulation in both brain and blood, MRPL4 and MRPS7.

CONCLUSIONS

Our results support the accumulating evidence of impaired mitochondrial activity in schizophrenia. While further research is needed to validate mitoribosomes' role as biomarkers, this direction has the potential to promote patients' stratification and personalised treatment for schizophrenia.

Differences in Psychiatric Comorbidities and Gender Distribution among Three Clusters of Personality Disorders: A Nationwide Population-Based Study

Personality disorders (PDs) are grouped into clusters A, B, and C. However, whether the three clusters of PDs have differences in comorbid mental disorders or gender distribution is still lacking sufficient evidence. We aim to investigate the distribution pattern across the three clusters of PDs with a population-based cohort study. This study used the Taiwan national database between 1995 and 2013 to examine the data of patients with cluster A PDs, cluster B PDs, or cluster C PDs. We compared the differences of psychiatric comorbidities classified in the Diagnostic and Statistical Manual of Mental Disorders, fifth edition across the three clusters of PDs. Moreover, we formed gender subgroups of the three PDs to observe the discrepancy between male and female. Among the 9845 patients, those with cluster A PDs had the highest proportion of neurodevelopmental disorders, schizophrenia and neurocognitive disorders, those with cluster B PDs demonstrated the largest percentage of bipolar disorders, trauma and stressor disorders, feeding and eating disorders, and substance and addictive disorders, and those with cluster C PDs had the greatest proportion of depressive disorders, anxiety disorders, obsessive–compulsive disorders, somatic symptom disorders, and sleep–wake disorders. The gender subgroups revealed significant male predominance in neurodevelopmental disorders and female predominance in sleep–wake disorders across all three clusters of PDs. Our findings support that some psychiatric comorbidities are more prevalent in specified cluster PDs and that gender differences exist across the three clusters of PDs. These results are an important reference for clinicians who are developing services that target real-world patients with PDs.

The personality dispositions and resting-state neural correlates associated with aggressive children

Despite aggression being detrimental to children's physical health, mental health and social development, the dispositional and neurological antecedents of aggression in the child are poorly understood. Here we examined the relationship between trait aggression as measured by Buss and Warren's Aggression Questionnaire and personality traits measured with Big Five Questionnaire for Children in 77 primary-school children and recorded resting-state brain activity (fractional amplitude of low-frequency fluctuations [fALFF]) and resting-state functional connectivity (rsFC) using functional magnetic resonance imaging. The present results showed that trait aggression was negatively correlated with agreeableness and positively correlated with neuroticism. The brain analyses showed that children with a higher propensity for aggression had a lower fALFF mainly in the left superior temporal gyrus, right parahippocampal gyrus and left supramarginal gyrus. Physical and total aggressions were negatively associated with rsFC between the right parahippocampal gyrus and the right putamen. Further analysis revealed that this rsFC could moderate the influence of neuroticism on total aggression. Moreover, the results suggest the presence of a sex difference in the neurodevelopmental mechanisms underlying aggression in middle childhood. Overall, our findings indicate that aggressive children have lower agreeableness and higher neuroticism, and the underlying neural systems are mainly implicated in social judgment and empathy.

Frontal and temporal cortical volume, white matter tract integrity, and hemispheric asymmetry in schizotypal personality disorder

Abnormalities in temporal and frontal cortical volume, white matter tract integrity, and hemispheric asymmetry have been implicated in schizophrenia-spectrum disorders. Schizotypal personality disorder can provide insight into vulnerability and protective factors in these disorders without the confounds associated with chronic psychosis. However, multimodal imaging and asymmetry studies in SPD are sparse. Thirty-seven individuals with SPD and 29 healthy controls (HC) received clinical interviews and 3T magnetic resonance T1-weighted and diffusion tensor imaging scans. Mixed ANOVAs were performed on gray matter volumes of the lateral temporal regions involved in auditory and language processing and dorsolateral prefrontal cortex involved in executive functioning, as well as fractional anisotropy (FA) of prominent white matter tracts that connect frontal and temporal lobes. In the temporal lobe regions, there were no group differences in volume, but SPD had reduced right>left middle temporal gyrus volume asymmetry compared to HC and lacked the right>left asymmetry in the inferior temporal gyrus volume seen in HC. In the frontal regions, there were no differences between groups on volume or asymmetry. In the white matter tracts, SPD had reduced FA in the left sagittal stratum and superior longitudinal fasciculus, and increased right>left asymmetry in sagittal stratum FA compared to HC. In the SPD group, lower left superior longitudinal fasciculus FA was associated with greater severity of disorganization symptoms. Findings suggest that abnormities in structure and asymmetry of temporal regions and frontotemporal white matter tract integrity are implicated in SPD pathology.

Emotion processing deficits in the different dimensions of psychometric schizotypy

Schizotypy refers to a personality structure indicating "proneness" to schizophrenia. Around 10% of the general population has increased schizotypal traits, they also share other core features with schizophrenia and are thus at heightened risk for developing schizophrenia and spectrum disorders. A key aspect in schizophrenia-spectrum pathology is the impairment observed in emotion-related processes. This review summarizes findings on impairments related to central aspects of emotional processes, such as emotional disposition, alexithymia, facial affect recognition and speech prosody, in high schizotypal individuals in the general population. Although the studies in the field are not numerous, the current findings indicate that all these aspects of emotional processing are deficient in psychometric schizotypy, in accordance to the schizophrenia-spectrum literature. A disturbed frontotemporal neural network seems to be the critical link between these impairments, schizotypy and schizophrenia. The limitations of the current studies and suggestions for future research are discussed.

A Neurobiological Model of Borderline Personality Disorder: Systematic and Integrative Review

Borderline personality disorder (BPD) is a severe mental disorder with a multifactorial etiology. The development and maintenance of BPD is sustained by diverse neurobiological factors that contribute to the disorder's complex clinical phenotype. These factors may be identified using a range of techniques to probe alterations in brain systems that underlie BPD. We systematically searched the scientific literature for empirical studies on the neurobiology of BPD, identifying 146 articles in three broad research areas: neuroendocrinology and biological specimens; structural neuroimaging; and functional neuroimaging. We consolidate the results of these studies and provide an integrative model that attempts to incorporate the heterogeneous findings. The model specifies interactions among endogenous stress hormones, neurometabolism, and brain structures and circuits involved in emotion and cognition. The role of the amygdala in BPD is expanded to consider its functions in coordinating the brain's dynamic evaluation of the relevance of emotional stimuli in the context of an individual's goals and motivations. Future directions for neurobiological research on BPD are discussed, including implications for the Research Domain Criteria framework, accelerating genetics research by incorporating endophenotypes and gene × environment interactions, and exploring novel applications of neuroscience findings to treatment research.

Genetic and Neuroimaging Features of Personality Disorders: State of the Art

Personality disorders often act as a common denominator for many psychiatric problems, and studies on personality disorders contribute to the etiopathology, diagnosis, and treatment of many mental disorders. In recent years, increasing evidence from various studies has shown distinctive features of personality disorders, and that from genetic and neuroimaging studies has been especially valuable. Genetic studies primarily target the genes encoding neurotransmitters and enzymes in the serotoninergic and dopaminergic systems, and neuroimaging studies mainly focus on the frontal and temporal lobes as well as the limbic-paralimbic system in patients with personality disorders. Although some studies have suffered due to unclear diagnoses of personality disorders and some have included few patients for a given personality disorder, great opportunities remain for investigators to launch new ideas and technologies in the field.

Sensory gating disturbances in the spectrum: similarities and differences in schizotypal personality disorder and schizophrenia

BACKGROUND

DSM-5 places schizophrenia on a continuum from severe, chronic schizophrenia to the attenuated schizophrenia-like traits of schizotypal personality disorder (SPD), the prototypic schizophrenia-related personality disorder. SPD shares common genetic and neurobiological substrates with schizophrenia, including information processing abnormalities, although they are less marked. This is the first study to directly compare the P50 evoked electroencephalographic response-a measure of sensory gating and a neurophysiological endophenotype-between schizophrenia-spectrum groups. Two hypotheses were tested: (1) Compared with healthy controls (HCs), schizophrenia patients show reduced P50 suppression and SPD patients resemble schizophrenia but exhibit less marked deficits; and (2) Deficient P50 suppression in SPD is associated with greater clinical symptom severity.

METHODS

P50 was assessed in 32 schizophrenia-spectrum disorder patients (12 SPD, 20 schizophrenia patients) and 25 demographically-matched HCs. The standard conditioning (C)-testing (T) paradigm was used and P50 suppression was quantified using the T-C difference and the T/C ratio.

RESULTS

All P50 measures showed a linear, stepwise pattern with the SPD group intermediate between the HC and schizophrenia groups. Compared with HCs, both patient groups had lower conditioning and T-C difference values. Among the SPD group, greater clinical symptom severity was associated with greater conditioning-response amplitude deficits.

CONCLUSION

These findings: (1) are novel in showing that P50 deficits in SPD resemble those observed in schizophrenia, albeit less marked; (2) support the concept that the phenomenological link between SPD and schizophrenia lies in shared neurocognitive/neurophysiological pathologies; and (3) provide evidence that P50 is a neurophysiological endophenotype for schizophrenia-spectrum disorders.

The association of post-stroke anhedonia with salivary cortisol levels and stroke lesion in hippocampal/parahippocampal region

BACKGROUND

Anhedonia constitutes a coherent construct, with neural correlates and negative clinical impact, independent of depression. However, little is known about the neural correlates of anhedonia in stroke patients. In this study, we investigated the association of post-stroke anhedonia with salivary cortisol levels and stroke location and volume.

PATIENTS AND METHODS

A psychiatrist administered the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition to identify anhedonia in 36 inpatients, without previous depression, consecutively admitted in a neurology clinic in the first month after a first-ever ischemic stroke. Salivary cortisol levels were assessed in the morning, evening, and after a dexamethasone suppression test. We used magnetic resonance imaging and a semi-automated brain morphometry method to assess stroke location, and the MRIcro program according to the Brodmann Map to calculate the lesion volume.

RESULTS

Patients with anhedonia had significantly larger diurnal variation (P-value =0.017) and higher morning levels of salivary cortisol (1,671.9±604.0 ng/dL versus 1,103.9±821.9 ng/dL; P-value =0.022), and greater stroke lesions in the parahippocampal gyrus (Brodmann area 36) compared to those without anhedonia (10.14 voxels; standard deviation ±17.72 versus 0.86 voxels; standard deviation ±4.64; P-value =0.027). The volume of lesion in the parahippocampal gyrus (Brodmann area 36) was associated with diurnal variation of salivary cortisol levels (rho=0.845; P-value =0.034) only in anhedonic patients.

CONCLUSION

Our findings suggest that anhedonia in stroke patients is associated with the volume of stroke lesion in the parahippocampal gyrus and with dysfunction of the hypothalamic-pituitary-adrenal axis.

Dialectical behavior therapy alters emotion regulation and amygdala activity in patients with borderline personality disorder

OBJECTIVE

Siever and Davis' (1991) psychobiological framework of borderline personality disorder (BPD) identifies affective instability (AI) as a core dimension characterized by prolonged and intense emotional reactivity. Recently, deficient amygdala habituation, defined as a change in response to repeated relative to novel unpleasant pictures within a session, has emerged as a biological correlate of AI in BPD. Dialectical behavior therapy (DBT), an evidence-based treatment, targets AI by teaching emotion-regulation skills. This study tested the hypothesis that BPD patients would exhibit decreased amygdala activation and improved habituation, as well as improved emotion regulation with standard 12-month DBT.

METHODS

Event-related fMRI was obtained pre- and post-12-months of standard-DBT in unmedicated BPD patients. Healthy controls (HCs) were studied as a benchmark for normal amygdala activity and change over time (n = 11 per diagnostic-group). During each scan, participants viewed an intermixed series of unpleasant, neutral and pleasant pictures presented twice (novel, repeat). Change in emotion regulation was measured with the Difficulty in Emotion Regulation (DERS) scale.

RESULTS

fMRI results showed the predicted Group × Time interaction: compared with HCs, BPD patients exhibited decreased amygdala activation with treatment. This post-treatment amygdala reduction in BPD was observed for all three pictures types, but particularly marked in the left hemisphere and during repeated-emotional pictures. Emotion regulation measured with the DERS significantly improved with DBT in BPD patients. Improved amygdala habituation to repeated-unpleasant pictures in patients was associated with improved overall emotional regulation measured by the DERS (total score and emotion regulation strategy use subscale).

CONCLUSION

These findings have promising treatment implications and support the notion that DBT targets amygdala hyperactivity-part of the disturbed neural circuitry underlying emotional dysregulation in BPD. Future work includes examining how DBT-induced amygdala changes interact with frontal-lobe regions implicated in emotion regulation.

Regional cortical thinning may be a biological marker for borderline personality disorder

OBJECTIVE

We investigated cerebral cortical thickness and its relation to measurements of difficulties with identifying and describing emotions in patients with borderline personality disorder (BPD).

METHOD

Eighteen SCID-II-diagnosed female patients with BPD and 21 healthy female controls underwent magnetic resonance imaging and completed the Toronto Alexithymia Scale (TAS). First, regional cortical thickness across the cerebral surface was compared between patients and healthy controls. Then, analyses of the association between cortical thickness and TAS subscales were performed in patients.

RESULTS

Compared with controls, patients exhibited clusters of significantly reduced cortical thickness in the left medial and lateral prefrontal cortex, left temporoparietal junction, bilateral temporal poles, and bilateral paracentral lobules. Significant negative associations were observed between cortical thickness and the 'Difficulties Describing Feelings' TAS subscale (DDF) scores in patients. The anatomical distribution of these associations was highly overlapping with the group differences in cortical thickness.

CONCLUSION

The pattern of regions exhibiting cortical thinning in patients resembles a network of cortical structures repeatedly shown to be involved in social cognition. The results of the DDF analyses suggest that the thinning may partly be related to interpersonal dysfunction in patients with BPD. The pattern of thinning may represent a potential biological marker for BPD.

Visual-spatial working memory performance and temporal gray matter volume predict schizotypal personality disorder group membership

BACKGROUND

Prior work shows individuals with schizotypal personality disorder (SPD) evince temporal lobe volume abnormalities similar to schizophrenia but sparing of prefrontal cortex, which may mitigate psychosis and the severe neurocognitive impairments observed in schizophrenia. This study examined the extent to which frontal-temporal gray matter volume and neurocognitive performance predict: (1) SPD group membership in a demographically-balanced sample of 51 patients and 37 healthy controls; and (2) symptom severity in SPD.

METHODS

Dimensional gray-matter volume (left frontal-temporal regions (Brodmann area (BA) 10, 21, 22)) and neurocognitive performance on key memory tasks (California Verbal Learning Test (CVLT), Dot Test, Paced Auditory Serial Addition Test (PASAT)), all salient to schizophrenia-spectrum disorders were examined in a multi-variable model.

RESULTS

Middle temporal gyrus (BA21) volume and spatial-working memory (Dot Test) performance were significant predictors of SPD group membership likelihood, with poorer working-memory performance indicating increased probability of SPD membership. Combining across regional volumes or cognitive measures resulted in fair-to-good discrimination of group membership, but including neurocognitive and non-collinear regional volume measures together resulted in a receiver-operating-characteristic (ROC) curve with improved diagnostic discrimination. Larger BA10 volume in dorsolateral prefrontal cortex (DLPFC) significantly predicted less symptom severity in SPD.

CONCLUSIONS

These findings suggest that temporal lobe volume and spatial-working memory performance are promising biological/phenotype markers for likelihood of SPD classification, while greater DLPFC volume may serve as a protective factor.

Working memory in schizotypal personality disorder: fMRI activation and deactivation differences

BACKGROUND

Schizotypal personality disorder (SPD) is considered a schizophrenia spectrum disorder, sharing with schizophrenia cognitive, neuropsychological, epidemiological, and biological characteristics. Working memory may be one area of shared deficit, although to date, this is only the second study to investigate working memory in SPD using fMRI.

METHODS

In a block-design fMRI study, fifteen antipsychotic-naïve SPD and sixteen healthy control subjects performed blocks of a 2back visual working memory task and 0back continuous performance task while undergoing whole-brain fMRI at 3T. Whole-brain analyses were performed for the 0back>rest (fixation baseline) and the 2back>0back contrasts (isolating the working memory component from the visual perception and attention component). Parameter estimates were extracted to determine whether observed differences were due to task-induced activation and/or deactivation.

RESULTS

Activation differences emerged between the two groups, without differences in task performance. In the 0back task, SPD showed decreased task-induced activation of the left postcentral gyrus. In the 2back>0back contrast, HC showed greater task-induced activation of the left posterior cingulate gyrus, superior temporal gyrus, insula, and middle frontal gyrus. These differences were due to SPD subjects' decreased task-induced activation in the left posterior cingulate gyrus, and task-induced deactivation in the remaining regions.

CONCLUSIONS

These findings suggest that compared to HC subjects, individuals with SPD may achieve comparable working memory performance. However, differences emerge at the level of functional neural activation, attributable to different task-induced activation and deactivation patterns. Such differential recruitment of neural resources may be beneficial, contributing to SPD subjects' ability to perform these tasks comparably to HC subjects.

Neuroimaging findings in schizotypal personality disorder: a systematic review

BACKGROUND

Schizotypal personality disorder is the prototypical schizophrenia-spectrum condition, sharing similar phenomenological, cognitive, genetic, physiological, neurochemical, neuroanatomical and neurofunctional abnormalities with schizophrenia. Investigations into SPD circumvent many confounds inherent to schizophrenia such as medication and institutionalization. Hence, SPD offers a unique vantage point from which to study schizophrenia-spectrum conditions.

METHODS

We systematically reviewed the neuroimaging literature in SPD to establish: (1) whether there are concordant findings in SPD and schizophrenia, possibly reflective of core pathology between the two conditions and (2) whether there are discordant findings in SPD and schizophrenia, possibly reflecting protective factors in the former. The findings are synthesized across structural and functional neuroimaging domains.

RESULTS

A total of 54 studies were identified. Medial temporal lobe structures seem to be compromised in both SPD and schizophrenia. In schizophrenia prefrontal structures are further compromised, whereas in SPD these seem to be larger-than-normal, possibly reflecting a compensatory mechanism. Additional pathology is discussed, including evidence of aberrant subcortical dopaminergic functioning.

CONCLUSIONS

SPD is a schizophrenia-spectrum condition that shares pathology with schizophrenia, but is distinct in showing unique neural findings. Future studies are needed to confirm and localize regions of common and disparate pathology between SPD and schizophrenia.

Morphometric differences in central stress-regulating structures between women with and without borderline personality disorder

BACKGROUND

Experiences of early life stress, increased psychological arousal and the body's physiologic stress response seem to play an important role in the pathogenesis and maintenance of borderline personality disorder (BPD). In the present study, we investigated alterations in grey matter of central stress-regulating structures in female patients with BPD.

METHODS

We examined T1-weighted structural magnetic resonance imaging scans of unmedicated, right-handed female patients with BPD (according to DSM-IV criteria) and healthy controls matched for age, intelligence and education using fully automated DARTEL voxel-based morphometry. Our regions of interest analyses included the hippocampus, amygdala, anterior cingulate cortex (ACC) and hypothalamus.

RESULTS

We enrolled 30 patients and 33 controls in our study. The grey matter of patients with BPD was reduced in the hippocampus, but increased in the hypothalamus compared with healthy participants. Hypothalamic volume correlated positively with the history of traumatization in patients with BPD. No significant alterations were found in the amygdala and ACC.

LIMITATIONS

This study is limited by the lack of measures of corticotropin-releasing hormone, adrenocorticotropic hormone and cortisol levels. Furthermore, moderate sample size and comorbid disorders need to be considered.

CONCLUSION

Our findings provide new evidence for grey matter alterations in the hypothalamus and replicate previously reported decrements in hippocampal volume in patients with BPD. Understanding the role of the hypothalamus and other central stress-regulating structures could help us to further understand the neurobiological underpinnings of this complex disorder.

Larger putamen size in antipsychotic-naïve individuals with schizotypal personality disorder

OBJECTIVE

To (a) compare the size of the dorsal and ventral striatum (caudate and putamen) in a large sample of antipsychotic-naïve individuals with schizotypal personality disorder (SPD) and healthy control participants; (b) examine symptom correlates of striatal size in SPD.

METHODS

The left and right caudate and putamen were hand-traced on structural MRI at five dorsal to ventral slice levels in 76 SPD and 148 healthy control participants. A Group×Region (caudate, putamen)×Slice (1-5: ventral, 2, 3, 4, dorsal)×Hemisphere (left, right) mixed-model MANOVA was conducted on size relative to whole brain.

RESULTS

Primary results showed that compared with the controls, the SPD group showed (a) larger bilateral putamen size overall and this enlargement was more pronounced at the most ventral and dorsal levels; in contrast, there were no between-group differences in caudate volume; (b) larger bilateral size of the striatum ventrally, averaged across the caudate and putamen. Among the SPD group, larger striatal size ventrally, particularly in the left hemisphere was associated with less severe paranoid symptoms.

CONCLUSIONS

Striatal size is abnormal in SPD and resembles that of patients with schizophrenia who respond well to antipsychotic treatment. The results suggest that striatal size may be an important endophenotype to consider when developing new pharmacological treatments and when studying factors mitigating psychosis.

Anterior limb of the internal capsule in schizotypal personality disorder: fiber-tract counting, volume, and anisotropy

Mounting evidence suggests that white matter abnormalities and altered subcortical-cortical connectivity may be central to the pathology of schizophrenia (SZ). The anterior limb of the internal capsule (ALIC) is an important thalamo-frontal white-matter tract shown to have volume reductions in SZ and to a lesser degree in schizotypal personality disorder (SPD). While fractional anisotropy (FA) and connectivity abnormalities in the ALIC have been reported in SZ, they have not been examined in SPD. In the current study, magnetic resonance (MRI) and diffusion tensor imaging (DTI) were obtained in age- and sex-matched individuals with SPD (n=33) and healthy controls (HCs; n=38). The ALIC was traced bilaterally on five equally spaced dorsal-to-ventral axial slices from each participant's MRI scan and co-registered to DTI for the calculation of FA. Tractography was used to examine tracts between the ALIC and two key Brodmann areas (BAs; BA10, BA45) within the dorsolateral prefrontal cortex (DLPFC). Compared with HCs, the SPD participants exhibited (a) smaller relative volume at the mid-ventral ALIC slice level but not the other levels; (b) normal FA within the ALIC; (c) fewer relative number of tracts between the most-dorsal ALIC levels and BA10 but not BA45 and (d) fewer dorsal ALIC-DLPFC tracts were associated with greater symptom severity in SPD. In contrast to prior SZ studies that report lower FA, individuals with SPD show sparing. Our findings are consistent with a pattern of milder thalamo-frontal dysconnectivity in SPD than schizophrenia.

Multimodal morphometry and functional magnetic resonance imaging in schizophrenia and auditory hallucinations

AIM: To validate a multimodal [structural and functional magnetic resonance (MR)] approach as coincidence brain clusters are hypothesized to correlate with clinical severity of auditory hallucinations.

METHODS: Twenty-two patients meeting Diagnostic and Statistical Manual of Mental Disorders (fourth edition, DSM-IV) criteria for schizophrenia and experiencing persistent hallucinations together with 28 healthy controls were evaluated with structural and functional MR imaging with an auditory paradigm designed to replicate those emotions related to the patients’ hallucinatory experiences. Coincidence maps were obtained by combining structural maps of gray matter reduction with emotional functional increased activation. Abnormal areas were correlated with the brief psychiatric rating scale (BPRS) and the psychotic symptom rating scale (PSYRATS) scales.

RESULTS: The coincidence analysis showed areas with coexistence gray matter reductions and emotional activation in bilateral middle temporal and superior temporal gyri. Significant negative correlations between BPRS and PSYRATS scales were observed. BPRS scores were negatively correlated in the middle temporal gyrus (right) (t = 6.86, P = 0.001), while negative PSYRATS correlation affected regions in both the superior temporal gyrus (left) (t = 7.85, P = 0.001) and middle temporal gyrus (left) (t = 4.97, P = 0.002).

CONCLUSION: Our data identify left superior and middle temporal gyri as relevant areas for the understanding of auditory hallucinations in schizophrenia. The use of multimodal approaches, sharing structural and functional information, may demonstrate areas specifically linked to the severity of auditory hallucinations.

Auditory steady state response in the schizophrenia, first-degree relatives, and schizotypal personality disorder

The power and phase synchronization of the auditory steady state response (ASSR) at 40 Hz stimulation is usually reduced in schizophrenia (SZ). The sensitivity of the 40 Hz ASSR to schizophrenia spectrum phenotypes, such as schizotypal personality disorder (SPD), or to familial risk has been less well characterized. We compared the ASSR of patients with SZ, persons with schizotypal personality disorder, first degree relatives of patients with SZ, and healthy control participants. ASSRs were obtained to 20, 30, 40 and 50 Hz click trains, and assessed using measures of power (mean trial power or MTP) and phase consistency (phase locking factor or PLF). The MTP to 40 Hz stimulation was reduced in relatives, and there was a trend for MTP reduction in SZ. The 40 Hz ASSR was not reduced in SPD participants. PLF did not differ among groups. These data suggest the 40 Hz ASSR is sensitive to familial risk factors associated with schizophrenia.

A review of structural MRI and diffusion tensor imaging in schizotypal personality disorder

Individuals with schizotypal personality disorder (SPD) share genetic, phenomenologic, and cognitive abnormalities with people diagnosed with schizophrenia. To date, 15 structural MRI studies of the brain have examined size, and 3 diffusion tensor imaging studies have examined white matter connectivity in SPD. Overall, both types of structural neuroimaging modalities have shown temporal lobe abnormalities similar to those observed in schizophrenia, while frontal lobe regions appear to show more sparing. This intriguing pattern suggests that frontal lobe sparing may suppress psychosis, which is consistent with the idea of a possible neuroprotective factor. In this paper, we review these 18 studies and discuss whether individuals with SPD who both resemble and differ from schizophrenia patients in their phenomenology, share some or all of the structural brain imaging characteristics of schizophrenia. We attempt to group the MRI abnormalities in SPD into three patterns: 1) a spectrum of severity-abnormalities are similar to those observed in schizophrenia but not so severe; 2) a spectrum of region-abnormalities affecting some, but not all, brain regions affected in schizophrenia; and 3) a spectrum of compensation-abnormalities reflecting greater-than-normal white matter volume, possibly serving as a buffer or compensatory mechanism protecting the individual with SPD from the frank psychosis observed in schizophrenia.

A follow-up MRI study of the fusiform gyrus and middle and inferior temporal gyri in schizophrenia spectrum

While longitudinal magnetic resonance imaging (MRI) studies have demonstrated progressive gray matter reduction of the superior temporal gyrus (STG) during the early phases of schizophrenia, it remains largely unknown whether other temporal lobe structures also exhibit similar progressive changes and whether these changes, if present, are specific to schizophrenia among the spectrum disorders. In this longitudinal MRI study, the gray matter volumes of the fusiform, middle temporal, and inferior temporal gyri were measured at baseline and follow-up scans (mean inter-scan interval=2.7 years) in 18 patients with first-episode schizophrenia, 13 patients with schizotypal disorder, and 20 healthy controls. Both schizophrenia and schizotypal patients had a smaller fusiform gyrus than controls bilaterally at both time points, whereas no group difference was found in the middle and inferior temporal gyri. In the longitudinal comparison, the schizophrenia patients showed significant fusiform gyrus reduction (left, -2.6%/year; right, -2.3%/year) compared with schizotypal patients (left: -0.4%/year; right: -0.2%/year) and controls (left: 0.1%/year; right: 0.0%/year). However, the middle and inferior temporal gyri did not exhibit significant progressive gray matter change in all diagnostic groups. In the schizophrenia patients, a higher cumulative dose of antipsychotics during follow-up was significantly correlated with less severe gray matter reduction in the left fusiform gyrus. The annual gray matter loss of the fusiform gyrus did not correlate with that of the STG previously reported in the same subjects. Our findings suggest regional specificity of the progressive gray matter reduction in the temporal lobe structures, which might be specific to overt schizophrenia within the schizophrenia spectrum.

Identification of psychopathic individuals using pattern classification of MRI images

BACKGROUND

Psychopathy is a disorder of personality characterized by severe impairments of social conduct, emotional experience, and interpersonal behavior. Psychopaths consistently violate social norms and bring considerable financial, emotional, or physical harm to others and to society as a whole. Recent developments in analysis methods of magnetic resonance imaging (MRI), such as voxel-based-morphometry (VBM), have become major tools to understand the anatomical correlates of this disorder. Nevertheless, the identification of psychopathy by neuroimaging or other neurobiological tools (e.g., genetic testing) remains elusive.

METHODS/PRINCIPAL FINDINGS

The main aim of this study was to develop an approach to distinguish psychopaths from healthy controls, based on the integration between pattern recognition methods and gray matter quantification. We employed support vector machines (SVM) and maximum uncertainty linear discrimination analysis (MLDA), with a feature-selection algorithm. Imaging data from 15 healthy controls and 15 psychopathic individuals (7 women in each group) were analyzed with SPM2 and the optimized VBM preprocessing routines. Participants were scanned with a 1.5 Tesla MRI system. Both SVM and MLDA achieved an overall leave-one-out accuracy of 80%, but SVM mapping was sparser than using MLDA. The superior temporal sulcus/gyrus (bilaterally) was identified as a region containing the most relevant information to separate the two groups.

CONCLUSION/SIGNIFICANCE

These results indicate that gray matter quantitative measures contain robust information to predict high psychopathy scores in individual subjects. The methods employed herein might prove useful as an adjunct to the established clinical and neuropsychological measures in patient screening and diagnostic accuracy.

Neuroanatomical profiles of personality change in frontotemporal lobar degeneration

BACKGROUND

The neurobiological basis of personality is poorly understood. Frontotemporal lobar degeneration (FTLD) frequently presents with complex behavioural changes, and therefore potentially provides a disease model in which to investigate brain substrates of personality.

AIMS

To assess neuroanatomical correlates of personality change in a cohort of individuals with FTLD using voxel-based morphometry (VBM).

METHOD

Thirty consecutive individuals fulfilling consensus criteria for FTLD were assessed. Each participant's carer completed a Big Five Inventory (BFI) questionnaire on five key personality traits; for each trait, a change score was derived based on current compared with estimated premorbid characteristics. All participants underwent volumetric brain magnetic resonance imaging. A VBM analysis was implemented regressing change score for each trait against regional grey matter volume across the FTLD group.

RESULTS

The FTLD group showed a significant decline in extraversion, agreeableness, conscientiousness and openness and an increase in neuroticism. Change in particular personality traits was associated with overlapping profiles of grey matter loss in more anterior cortical areas and relative preservation of grey matter in more posterior areas; the most robust neuroanatomical correlate was identified for reduced conscientiousness in the region of the posterior superior temporal gyrus.

CONCLUSIONS

Quantitative measures of personality change in FTLD can be correlated with changes in regional grey matter. The neuroanatomical profiles for particular personality traits overlap brain circuits previously implicated in aspects of social cognition and suggest that dysfunction at the level of distributed cortical networks underpins personality change in FTLD.

Children's Brain Development Benefits from Longer Gestation

Disruptions to brain development associated with shortened gestation place individuals at risk for the development of behavioral and psychological dysfunction throughout the lifespan. The purpose of the present study was to determine if the benefit for brain development conferred by increased gestational length exists on a continuum across the gestational age spectrum among healthy children with a stable neonatal course. Neurodevelopment was evaluated with structural magnetic resonance imaging in 100 healthy right-handed 6- to 10-year-old children born between 28 and 41 gestational weeks with a stable neonatal course. Data indicate that a longer gestational period confers an advantage for neurodevelopment. Longer duration of gestation was associated with region-specific increases in gray matter density. Further, the benefit of longer gestation for brain development was present even when only children born full term were considered. These findings demonstrate that even modest decreases in the duration of gestation can exert profound and lasting effects on neurodevelopment for both term and preterm infants and may contribute to long-term risk for health and disease.

Left but not right hemisphere semantic processing abnormalities in language comprehension in subjects with schizotypy traits

Thought and language disorders in schizophrenia and schizotypy are thought to result from hemispheric dysfunction during semantic processing. Left hemisphere (LH) abnormalities are well established, but little is known about right hemisphere (RH) semantic processes. We explored hemispheric processing in 50 healthy volunteers assigned to high (h-SZT) or low schizotypy (l-SZT) group using the Schizotypal Personality Questionnaire (SPQ). Subjects were asked to make semantic judgments on sentence pair ending with a target that was either expected word (EW) or an unexpected word from the same (related violation, RV) or a different category (unrelated violation, URV). Targets were presented in a dichotic manner to the left or right ear. Analyses of reaction times in the l-SZT group showed semantic compatibility effect (URV-EW) in the LH and semantic memory activation effect (RV-URV) as well as semantic compatibility effect in the RH. The h-SZT group showed semantic memory activation but no semantic compatibility effect in the LH, the RH pattern resembling that of the l-SZT group. The magnitude of the LH semantic compatibility effect was inversely correlated with SPQ total scores and SPQ Cognitive-perceptual factor. Thus, RH semantic processes are effective and there is a deficit in LH focused activation in schizotypy.

Cingulate and temporal lobe fractional anisotropy in schizotypal personality disorder

BACKGROUND

Consistent with the clinical picture of milder symptomatology in schizotypal personality disorder (SPD) than schizophrenia, morphological studies indicate SPD abnormalities in temporal lobe regions but to a much lesser extent in prefrontal regions implicated in schizophrenia. Lower fractional anisotropy (FA), a measure of white-matter integrity within prefrontal, temporal, and cingulate regions has been reported in schizophrenia but has been little studied in SPD.

AIMS

The study aim was to examine temporal and prefrontal white matter FA in 30 neuroleptic-naïve SPD patients and 35 matched healthy controls (HCs). We hypothesized that compared with HCs, SPD patients would exhibit lower FA in temporal lobe and anterior cingulum regions but relative sparing in prefrontal regions.

METHOD

We acquired diffusion tensor imaging (DTI) in all participants and examined FA in the white matter underlying Brodmann areas (BAs) in dorsolateral prefrontal (BAs 44, 45, and 46), temporal lobe (BAs 22, 21, and 20), and cingulum (BAs 25, 24, 31, 23, and 29) regions with a series of analyses using multivariate analysis of variance.

RESULTS

Compared with HCs, the SPD group had significantly lower FA in the left temporal lobe but not prefrontal regions. In the cingulum, FA was lower in the SPD group in the posterior regions (BAs 31 and 23), higher in the anterior (BA 25) regions and lower overall in the right but not the left cingulum. Among the SPD group, lower FA in the cingulum was associated with more severe negative symptoms (e.g., odd speech).

CONCLUSIONS

Similar to schizophrenia, our results indicate cingulum-temporal lobe FA abnormalities in SPD and suggest that cingulum abnormalities are associated with negative symptoms.

Dorso- and ventro-lateral prefrontal volume and spatial working memory in schizotypal personality disorder

Schizotypal personality disorder (SPD) individuals and borderline personality disorder (BPD) individuals have been reported to show neuropsychological impairments and abnormalities in brain structure. However, relationships between neuropsychological function and brain structure in these groups are not well understood. This study compared visual-spatial working memory (SWM) and its associations with dorsolateral prefrontal cortex (DLPFC) and ventrolateral prefrontal cortex (VLPFC) gray matter volume in 18 unmedicated SPD patients with no BPD traits, 18 unmedicated BPD patients with no SPD traits, and 16 healthy controls (HC). Results showed impaired SWM in SPD but not BPD, compared with HC. Moreover, among the HC group, but not SPD patients, better SWM performance was associated with larger VLPFC (BA44/45) gray matter volume (Fisher's Z p-values <0.05). Findings suggest spatial working memory impairments may be a core neuropsychological deficit specific to SPD patients and highlight the role of VLPFC subcomponents in normal and dysfunctional memory performance.

Borderline personality disorder and psychosis: a review

Early views of borderline personality disorder (BPD) were based on the idea that patients with this pathology were "on the border" of psychosis. However, more recent studies have not supported this view, although they have found evidence of a malevolent interpersonal evaluation and a significant proportion of BPD patients showing psychotic symptoms. For example, in one study, 24% of BPD patients reported severe psychotic symptoms and about 75% had dissociative experiences and paranoid ideation. Thus, we start with an overview regarding the prevalence of psychotic symptoms in BPD patients. Furthermore, we report findings of studies investigating the role of comorbidity (eg, post-traumatic stress disorder) in the severity and frequency of psychotic symptoms in BPD patients. We then present results of genetic and neurobiological studies comparing BPD patients with patients with schizophrenia or nonschizophrenic psychotic disorders. In conclusion, this review reveals that psychotic symptoms in BPD patients may not predict the development of a psychotic disorder but are often permanent and severe and need careful consideration by clinicians. Therefore, adequate diagnosis and treatment of psychotic symptoms in BPD patients is emphasized.

A follow-up MRI study of the superior temporal subregions in schizotypal disorder and first-episode schizophrenia

While longitudinal magnetic resonance imaging (MRI) studies have demonstrated progressive gray matter reduction of the superior temporal gyrus (STG) during the early phases of schizophrenia, it remains unknown whether patients with schizotypal features exhibit similar STG changes. In this study, longitudinal MRI data were obtained from 18 patients with first-episode schizophrenia, 13 patients with schizotypal disorder, and 20 healthy controls. The volumes of the STG and its subregions [planum polare (PP), Heschl gyrus (HG), planum temporale (PT), rostral STG, and caudal STG] were measured on baseline and follow-up (mean: 2.7 years) scans and were compared across groups. At the baseline, both the schizophrenia and schizotypal patients had smaller left PT and left caudal STG than the controls. In a longitudinal comparison, the schizophrenia patients showed significant gray matter reduction of the STG over time (left: -2.8%/year; right: -1.5%/year) compared with the schizotypal patients (left: -0.6%/year; right: -0.3%/year) and controls (left: 0.0%/year; right: -0.1%/year) without a prominent effect of subregion or type of antipsychotic (typical/atypical). In the schizophrenia patients, greater annual volume reductions of the left PP and right PT were correlated with less improvement of positive psychotic symptoms. A higher cumulative dose of antipsychotics during follow-up in schizophrenia was significantly correlated with less severe gray matter reductions in the left PT and bilateral caudal STG. Our findings suggest that the left posterior STG subregions are commonly reduced in diseases of the schizophrenia spectrum; whereas, schizophrenia patients exhibit further progressive STG changes associated with overt psychosis in the early years of the illness.

Superior temporal gyrus volume in teenagers with first-presentation borderline personality disorder

This magnetic resonance imaging study investigated the superior temporal gyrus (STG) subregion volumes in 20 teenagers with first-presentation borderline personality disorder (BPD) and 20 healthy controls. While the STG volume early in the course of BPD did not differ from that of healthy controls, the BPD participants with violent episodes had a smaller left caudal STG volume compared with those without such episodes during the previous 6 months. Our preliminary findings might reflect the neurobiological heterogeneity of the disorder.

An MRI study of the superior temporal subregions in first-episode patients with various psychotic disorders

Morphologic abnormalities of the superior temporal gyrus (STG) have been reported in schizophrenia, but have not been extensively studied in other psychotic disorders such as affective psychosis. In the present study, magnetic resonance imaging was used to examine the volumes of the STG and its subregions [planum polare (PP), Heschl gyrus (HG), planum temporale (PT), rostral STG, and caudal STG] in 162 first-episode patients with various psychotic disorders [46 schizophrenia (31 schizophrenia and 15 schizoaffective disorder), 57 schizophreniform disorder, 34 affective psychosis, and 25 other psychoses] and 62 age- and sex-matched healthy controls. The first-episode schizophrenia patients had significantly less gray matter in HG, PT, and caudal STG bilaterally compared with all other groups, but there was no difference between the controls and affective psychosis, schizophreniform disorder, or other psychoses for any STG subregion. The STG white matter volume did not differ between groups. Our findings indicate that morphologic abnormalities of the STG gray matter are specific to schizophrenia among various psychotic disorders, implicating its role in the underlying pathophysiology of schizophrenia.