A reassessment of the higher-order factor structure of the German Schizotypal Personality Questionnaire (SPQ-G) in German-speaking adults.

The Schizotypal Personality Questionnaire (SPQ) is a widely-used self-report instrument for the assessment of schizotypal personality traits. However, the factor structure of scores on English and non-English translations of the SPQ has been a matter of debate. With little previous factorial evaluation of the German version of the SPQ (SPQ-G), we re-assessed the higher-order factor structure of the measure.

The relationship between schizotypal facets and conspiracist beliefs via cognitive processes.

This study sought to replicate previous work showing relationships between components of schizotypy and conspiracist beliefs, and extend it by examining the mediating role of cognitive processes. An international online sample of 411 women and men (mean age = 35.41 years) completed measures of the schizotypal facets of Odd Beliefs or Magical Thinking and Ideas of Reference, conspiracist beliefs, and cognitive processes related to need for cognition, analytic thinking, and cognitive insight.

Psychometric properties of the Malay Schizotypal Personality Questionnaire: Measurement invariance and latent mean comparisons in Malaysian adults.

Introduction: The Schizotypal Personality Questionnaire (SPQ) is a widely used self-report measurement instrument for the assessment of schizotypal personality traits. However, the factor structure of the SPQ has been a matter of some debate. As a contribution to this debate, we examined the factor structure of the SPQ in Malaysian adults.

Clinical utility of magnetic resonance imaging in first-episode psychosis.

There is no consensus as to whether magnetic resonance imaging (MRI) should be used as part of the initial clinical evaluation of patients with first-episode psychosis (FEP).(a) To assess the logistical feasibility of routine MRI; (b) to define the clinical significance of radiological abnormalities in patients with FEP.Radiological reports from MRI scans of two FEP samples were reviewed; one comprised 108 patients and 98 healthy controls recruited to a research study and the other comprised 241 patients scanned at initial clinical presentation plus 66 healthy controls.

Examination of the factor structure of the Schizotypal Personality Questionnaire among British and Trinidadian adults.

Much debate in schizotypal research has centred on the factor structure of the Schizotypal Personality Questionnaire (SPQ), with research variously showing higher-order dimensionality consisting of two to seven dimensions. In addition, cross-cultural support for the stability of those factors remains limited. Here, we examined the factor structure of the SPQ among British and Trinidadian adults.

Differential relationship between neurological and cognitive dysfunction in first episode psychosis patients and in healthy individuals.

The minor neurological and cognitive deficits consistently reported in psychoses may reflect the same underlying brain dysfunction. Still, even in healthy individuals minor neurological abnormalities are associated with worse cognitive function. Therefore, establishing which neurological and cognitive deficits are specific to psychosis is essential to inform the pathophysiology of this disorder.

Insight, grey matter and cognitive function in first-onset psychosis.

Background: Several studies have suggested that neuropsychological and structural brain deficits are implicated in poor insight. Few insight studies however have combined neurocognitive and structural neuroanatomical measures.

Aims: Focusing on the ability to relabel psychotic symptoms as pathological, we examined insight, brain structure and neurocognition in first-onset psychosis.

Neurological abnormalities and cognitive ability in first-episode psychosis.

Background: It remains unclear if the excess of neurological soft signs, or of certain types of neurological soft signs, is common to all psychoses, and whether this excess is simply an epiphenomenon of the lower general cognitive ability present in psychosis.

Aims: To investigate whether an excess of neurological soft signs is independent of diagnosis (schizophrenia v. affective psychosis) and cognitive ability (IQ).

Grey matter abnormalities in first-episode schizophrenia and affective psychosis.

Background: Grey matter and other structural brain abnormalities are consistently reported in first-onset schizophrenia, but less is known about the extent of neuroanatomical changes in first-onset affective psychosis.

Aims: To determine which brain abnormalities are specific to (a) schizophrenia and (b) affective psychosis.

Method: We obtained dual-echo (proton density/T2-weighted) magnetic resonance images and carried out voxel-based analysis on the images of 73 patients with first-episode psychosis (schizophrenia n=44, affective psychosis n=29) and 58 healthy controls.

Sexually dimorphic changes in the amygdala in relation to delusional beliefs in first episode psychosis.

Background: Few attempts have been made to examine the relationship between amygdala abnormalities and specific symptoms in psychosis. The present study explored the relationship between amygdala morphology and mood congruent and mood incongruent delusional beliefs.

Methods: Amygdala volumes were measured in 43 patients presenting with delusional beliefs in the context of their first episode of psychosis and 43 healthy volunteers matched for age and gender.

Duration of untreated psychosis and neuropsychological function in first episode psychosis.

Purpose: We investigated whether duration of untreated psychosis (DUP) prior to first presentation was associated with cognitive function in first episode psychosis (FEP) subjects. We predicted that longer DUP would be associated with greater neurocognitive impairment.

Method: 180 subjects with schizophrenia (and 93 subjects with Other Psychoses) performed a neurocognitive battery assessing IQ, verbal learning, working memory, visual learning and speed of processing.

Insight in individuals with an At Risk Mental State.

Purpose: On average, people with an At Risk Mental State (ARMS) for psychosis are more willing to seek and accept clinical help than patients with psychotic disorders, suggesting that insight in this group is relatively less impaired. We compared the level and quality of insight in the ARMS and in first episode psychosis.

Materials And Methods: Insight about illness was assessed in subjects with an ARMS and in patients with first episode psychosis (FEP) who were and were not help-seeking, using the Schedule for Assessment of Insight (SAI-E).

Insight in psychosis and neuropsychological function: meta-analysis.

Background: One factor contributing to impaired awareness of illness (poor insight) in psychotic disorders may be neurocognitive deficits.

Method: A systematic review and meta-analysis were conducted after data extraction. Following an overall analysis, in which measures of different cognitive domains were taken together, more fine-grained analyses investigated whether there was a specific relation with frontal executive functioning, and whether this was influenced by diagnosis or the insight scales used.

The structural brain correlates of neurological soft signs in healthy individuals.

It has yet to be established whether neurological soft signs (NSS), which include poor motor coordination, sensory perceptual difficulties and difficulties in sequencing of complex motor tasks, result from specific or diffuse brain structural abnormalities. Studying the neuroanatomical basis of NSS in healthy individuals may help to identify which brain areas are specifically associated with these signs, while excluding the potential confounding effects of psychiatric and neurological disorders. We investigated the relationship between brain structure and NSS in 43 healthy individuals, using the Neurological Evaluation Scale for neurological assessment, and high resolution MRI and voxel-based methods of image analysis to investigate brain structure.

Increased pituitary volume in antipsychotic-free and antipsychotic-treated patients of the AEsop first-onset psychosis study.

Subjects at their first psychotic episode show an enlarged volume of the pituitary gland, but whether this is due to hypothalamic-pituitary-adrenal (HPA) axis hyperactivity, or to stimulation of the prolactin-secreting cells by antipsychotic treatment, is unclear. We measured pituitary volume, using 1.5-mm, coronal, 1.

Different effects of typical and atypical antipsychotics on grey matter in first episode psychosis: the AESOP study.

Typical antipsychotic drugs act on the dopaminergic system, blocking the dopamine type 2 (D2) receptors. Atypical antipsychotics have lower affinity and occupancy for the dopaminergic receptors, and a high degree of occupancy of the serotoninergic receptors 5-HT2A. Whether these different pharmacological actions produce different effects on brain structure remains unclear.

The structural brain correlates of neurological soft signs in AESOP first-episode psychoses study.

Patients with schizophrenia and related psychoses have an excess of minor neurological abnormalities (neurological soft signs) of unclear neuropathological origin. These include poor motor coordination, sensory perceptual difficulties and difficulties in sequencing complex motor tasks. Neurological soft signs seem not to reflect primary tract or nuclear pathology.