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Abstract Background Cognitive and cerebrovascular declines are potentially life-changing conditions which are associated with a substantial healthcare burden worldwide. While pharmacological approaches for the prevention of cognitive decline have been largely ineffective, exercise programs may be able to delay or prevent cognitive decline in those at risk. One putative mechanism for the beneficial impacts of exercise on brain health involves improvement in cerebrovascular function. Exercise positively affects arterial structure and function in peripheral arteries and microvessels, but the impacts on brain vascular function are largely unknown. Water immersion increases brain blood flow and shear stress, a mechanism that improves artery health. We hypothesised that repeated water immersion may lead to adaptations which enhance cerebrovascular function and health in humans. Methods/design 72 sedentary older adults (50 years and older) with subjective memory complaints were randomly assigned to a 24-week water-based or land-based walking program (designed to elicit differing stresses on blood vessels) or an education group. Measures of cerebral artery function and cognitive performance were assessed before and after the intervention, and again at 48 weeks to test for persistence of any benefits. Other outcomes included biochemistry, blood pressure, body composition and fitness. Discussion Water-based versus land-based exercise elicit different haemodynamic responses and, consequently, distinct patterns of shear stress in arteries, including those supplying the brain. If the exercise programs prove beneficial, this will inform future strategies for the prevention of cerebrovascular decline in the ageing 'healthy' population. Highlights • Rationale, study design and recruitment for investigating the effect of exercise on cerebrovascular function and cognition. • How does a walking intervention affect artery function, memory and cognition in previously inactive adults? • Does water-based walking, with different vascular stresses, affect cerebrovascular health differently from land walking? [ABSTRACT FROM AUTHOR]

Negative treatment from others is related to elevated levels of trait schizotypy, signifying increased risk for psychosis, but associations with helpful behaviour have been much less studied. Using the Stereotype Content Model we tested the hypothesis that passive and active forms of help would be associated with increased and decreased expression of schizotypy, respectively. Schizotypal traits were assessed in students (N=631) using positive (Perceptual Aberration) and negative (Social Anhedonia) subscales of the Wisconsin Schizotypy Scales-Brief. Experiences of active (intentional) and passive (less deliberative) harm and help were assessed with the Behaviour from Intergroup Affect and Stereotypes Treatment Scale. As predicted, the results showed that experiences of passive help from others were associated with a 2–3 fold increase in scores on schizotypy scales, whilst reports of active help tended to be associated with a decrease in scores on these scales. Results also showed that increased reports of active and passive harm were associated with elevated scores on negative and positive schizotypy subscales, consistent with prior research. These findings, bridging research on social stereotyping and schizotypal personality, challenge the assumption that helpful behaviour from others is always beneficial for individuals with schizotypal traits who are at increased risk for psychosis. [ABSTRACT FROM AUTHOR]

Design and aim: a cross sectional survey was undertaken to explore midwives' knowledge of, and attitudes towards, mental health disorders in childbearing women vis-à-vis their perceived mental health learning needs. Setting and participants: a 50.1% response rate included 238 midwives employed in the only public tertiary maternity hospital in Western Australia from March to June 2013. Method and findings: The survey comprised a mixture of custom-designed questions and vignettes presenting various disorders. Only 37.6% of midwives felt well-equipped to support women, whilst 50.2% reported insufficient access to information. Demand was highest for education on: personality disorders (77.8%); the impact of childbearing on mental health disorders (74.2%); and skills for handling stress and aggression (57.8%). Knowledge scores were variable: on average eight out of a maximum 13 questions were answered correctly, but few (2.7%) answered more than 11 correctly, and 3.7% scored r4 correct. Across disorders, recognition from vignettes was highest for depression (93.9%), and lowest for schizophrenia (65.6%). Surprisingly, there were no associations between general knowledge scores and previous mental health experience, recent professional development, or access to information around mental health. The majority endorsed positive beliefs about midwives' role in mental health assessment, and belief in women's recovery (83.5%), however, cluster analysis of warmth and competence ratings revealed negative stereotyping of mental health disorders. Key conclusions: Midwives accept it is their role to assess the mental health status of women but many feel ill-equipped to do so and express a strong desire for further knowledge and skills across a range of perinatal mental health topics. Attitudes to recovery are positive but negative stereotypes exist; therefore awareness of potential bias is important to negate their influence on care. Implications for practice: Learning needs may change due to trends in clinical practice. Strategies are needed to recognise negative beliefs and to ensure education is responsive to local contexts. [ABSTRACT FROM AUTHOR]

Abstract: Consistent with proposed impairments in the flexible control of action in Obsessive Compulsive Disorder (OCD), previous research has identified a bias towards low-level (action-focussed) rather than high-level (goal-focussed) descriptions of behaviour in individuals with subclinical checking (Belayachi & Van der Linden, 2009).The current study investigated whether this bias could be replicated, or was confounded with the influence of anxiety, and its relationship to another cognitive bias implicated in OCD, namely overestimation of threat. The comparison of high and low checking groups (stratified on anxiety) showed that anxiety was related to a tendency to focus on the mechanics of an action whilst, surprisingly, checking symptoms were associated with a tendency to focus on the goals of an action. These findings suggest that compulsive checkers may habitually attend to “why” actions are performed and their consequences. Additionally, high-level action identification and threat overestimation may provide separable causal influences on OCD. [Copyright &y& Elsevier]

Abstract: Voices provide a wealth of socially-relevant information, including cues to a speaker''s identity and emotion. Deficits recognising emotion from voice have been extensively described in schizophrenia, and linked specifically to auditory hallucinations (AH), but relatively little attention has been given to examining the ability to analyse speaker identity. Hence, the current study assessed the ability to discriminate between different speakers in people with schizophrenia (including 33 with and 32 without AH) compared to 32 healthy controls. Participants rated the degree of perceived identity similarity of pairs of unfamiliar voices pronouncing three-syllable words. Multidimensional scaling of the dissimilarity matrices was performed and the resulting dimensions were interpreted, a posteriori, via correlations with acoustic measures relevant to voice identity. A two-dimensional perceptual space was found to be appropriate for both schizophrenia patients and controls, with axes corresponding to the average fundamental frequency (F0) and formant dispersion (D f ). Patients with schizophrenia did not differ from healthy controls in their reliance on F0 in differentiating voices, suggesting that the ability to use pitch-based cues for discriminating voice identity may be relatively preserved in schizophrenia. On the other hand, patients (both with and without AH) made less use of D f in discriminating voices compared to healthy controls. This distorted pattern of responses suggests some potentially important differences in voice identity processing in schizophrenia. Formant dispersion has been linked to perceptions of dominance, masculinity, size and age in healthy individuals. These findings open some interesting new directions for future research. [Copyright &y& Elsevier]

Abstract: The continuum model of psychosis has been extremely influential. It assumes that psychotic symptoms, such as auditory verbal hallucinations (AVH), are not limited to patients with psychosis but also occur in healthy, non-clinical individuals – suggesting similar mechanisms of origin. Recent debate surrounding this model has highlighted certain differences, as well as similarities, in the phenomenology of AVH in clinical and non-clinical populations. These findings imply that there may, in fact, be only partial overlap of the mechanism(s) involved in generating AVH in these groups. We review evidence of continuity or similarity, and dissimilarity, in cognitive, and related neural processes, underlying AVH in clinical and non-clinical samples. The results reveal some shared (intrusive cognitions, inhibitory deficits) and some distinct (aspects of source memory and cerebral lateralization) mechanisms in these groups. The evidence, therefore, supports both continuous and categorical models of positive psychotic symptoms. The review considers potential risks of uncritical acceptance of the continuum model and highlights some important methodological issues for future research. [Copyright &y& Elsevier]

Abstract: Difficulties binding together information in memory have often been reported in individuals with schizophrenia, and have been linked with auditory hallucinations and the predisposition to hallucinate in particular. However, some inconsistencies remain. For example, we previously examined binding of two external sources (voice and location) in hallucination-prone individuals and found no evidence of a binding deficit using a working memory task that involved automatic binding. Consequently, the current study examined both automatic and intentional binding. The Launay-Slade Hallucination Scale-Revised (LSHS-R) was administered to 559 undergraduates from which high (25) and low (25) scorers were drawn. The binding tasks assessed either automatic or intentional binding of voice and location features. The results showed no significant differences between high and low hallucination-prone individuals in binding these two external sources of information, regardless of the type of binding (automatic or intentional) assessed. Furthermore, hallucination-prone individuals demonstrated no difficulties recognising individual features of voice identity or location. These findings suggest that some memory deficits may emerge only as psychosis fully develops. [Copyright &y& Elsevier]

Abstract: Emotion regulation involves the use of strategies to influence the experience and expression of emotions. Anxiety and depression are strongly associated with the positive symptoms of schizophrenia, such as auditory hallucinations (AHs). Individuals usually try to down-regulate (decrease) such emotions, consequently abnormal or maladaptive use of one or more of these down-regulatory processes (e.g. increased use of expressive suppression or maladaptive attentional deployment, i.e. rumination/worry) may play an important role in AHs (e.g. increasing AH severity and distress). This study examined the self-reported use of a range of emotion regulation strategies in individuals with schizophrenia and current AHs (SZ AH; N =34) and healthy controls (N =34). Two separable dimensions of hallucinatory experiences (severity and distress) were assessed together with measures of anxiety, depression and happiness. Within the SZ AH group, greater use of expressive suppression was associated with an increase in severity of AHs and greater disruption in daily life. In addition, rumination was significantly positively correlated with the distress (but not with the severity) associated with AHs. Within the control group, expressive suppression, rumination and worry were associated with more anxiety/depression and less happiness, as predicted. The implications of different emotion regulation strategies for the treatment of individuals with schizophrenia and AHs are discussed. [Copyright &y& Elsevier]

Abstract: Spatial working memory (SWM) dysfunction is a central finding in schizophrenia; however, more evidence of impaired maintenance over time is required. Consequently, the present study examined SWM maintenance over short unfilled delays, and with encoding equated. The influence of a vertical reference frame to support maintenance was also investigated. The performance of 58 patients with schizophrenia and 50 healthy controls was assessed using the Visuo-Spatial Working Memory (VSWM) Test across three unfilled delays (0, 2, and 4s). Inaccuracy of direction and distance responses was examined at each delay duration. The results showed that performance was significantly less accurate for both distance and direction responses at 2 and 4s delays in schizophrenia, but was not significantly different from controls at the 0s delay. Patients showed a particularly marked loss of accuracy between the time interval of 0–2s. Furthermore, schizophrenia participants exhibited significantly greater response variability at the vertical axis of symmetry than controls at the 2 and 4s delays, but not at the 0s delay. These data clearly show both impaired maintenance over time and difficulty using a vertical frame of reference in schizophrenia. The latter findings may reflect, in part, dysfunctional reference-related inhibition. [ABSTRACT FROM AUTHOR]

Abstract: Patients with schizophrenia and current auditory hallucinations exhibit a combination of deficits in context binding and intentional inhibition. Hallucinations also occur in the general population suggesting an underlying continuity of causal mechanisms, however, these experiences may also differ (e.g., in frequency), indicating some differences in aetiology. The aim of this study was to examine the frequency of hallucinatory experiences in healthy young adults and to assess whether difficulties in context binding characterize individuals highly predisposed to hallucinations. A modified version of the Launay–Slade hallucination scale-revised, including an assessment of the frequency of hallucination experiences, was completed by 615 undergraduates from which sub-samples of high (n =25) and low (n =27) scorers were drawn. Context memory ability was assessed using a voice–location binding task. The results showed that the frequency of hallucinations in high LSHS-R scorers was much less than that previously reported for individuals with schizophrenia. Furthermore, no group differences in context memory binding were observed, nor any association between hallucination frequency and context binding difficulties. The continuity model of hallucinations may overlook some important differences in hallucinatory experiences in the general population versus psychosis. [Copyright &y& Elsevier]

Abstract: Depression, anxiety and stress are commonly experienced by individuals predisposed to hallucinations and often accompany hallucinations in patients with schizophrenia. Analogous to hallucinatory experiences themselves, hallucination predisposition is measured as a multidimensional construct, though many competing structures have been proposed. Few studies have examined the association between negative affect and the individual subcomponents of hallucination predisposition. This paper describes two related studies: the first aimed to confirm the multifactorial structure of hallucinatory predisposition assessed with the Launay–Slade Hallucination Scale-Revised (LSHS-R; ); the second study aimed to examine the association between depression, anxiety, and stress and the separate components of hallucinatory predisposition in a non-psychiatric population. The first study showed that a three-factor model of hallucination predisposition () was superior to two competing models. The second study showed that anxiety was most consistently related to the predisposition to hallucinate, being associated with all three of the LSHS-R components, even after the variance shared with the other two affective constructs was partialled out. The possible influence of anxiety on cognitive mechanisms (in particular, intentional inhibition) potentially involved in hallucination predisposition was discussed. [Copyright &y& Elsevier]

Abstract: The goal of the present study was to examine the influence of age and gender on the factor structure of the Schizotypal Personality Questionnaire (). Schizotypal traits were assessed in a random sample of mature, adult community volunteers (average age 40 years). Four competing models of the latent factor structure were tested in the full sample (N =352). The resulting three-factor model was then assessed separately in males and females and in stratified subsamples, reflecting three age cohorts. The results showed that, in mature adults, males had higher scores than females on No Close Friends and Constricted Affect whilst females had higher scores on Social Anxiety and Odd Beliefs subscales. Older adults were also characterized by lower total SPQ scores than those reported previously for younger adults. Despite the presence of age and sex-related differences in mean SPQ scores, a three-factor model of schizotypal personality best characterized the SPQ responses from mature adults, replicating that reported previously in high-school and university-aged samples. The implications of these findings of SPQ factor structure invariance, across age and gender, are discussed with reference to studies investigating neurocognitive correlates of schizotypy (i.e. endophenotypes). [Copyright &y& Elsevier]

There is a growing literature describing a subgroup of “high-functioning” people with schizophrenia who show preserved intellectual ability (IQ). A detailed characterisation of the cognitive abilities of this group may be important in targeting appropriate treatment, management and services for patients with schizophrenia. It is a widely held belief that variation in cognitive processing speed is the basis of individual differences in intelligence. The main objective of this study was to identify subgroups of schizophrenia patients with preserved (N=45), deteriorated (N=47) and compromised (N=17) intellect in order to study whether these subgroups differ in specific cognitive abilities (e.g. executive functions) or in general cognitive processing speed, as measured with an inspection time (IT) task. The patients who displayed an average estimated premorbid IQ, with no evidence of IQ decline (premorbid-current IQ difference <10 points), were found to show better performance on measures of executive function (continuous performance task, verbal fluency) compared with patients in the deteriorated and compromised subgroups. Nevertheless, this represented significantly impaired performance relative to healthy controls. In contrast, the average inspection times of patients with preserved IQ were as slow as those obtained in the deteriorated or compromised groups, indicating that high functioning patients are impaired in terms of cognitive processing speed. Furthermore, the average IT for all schizophrenia groups was significantly slower than that of healthy controls. These findings suggest that high functioning patients with schizophrenia exhibit enduring cognitive difficulties that may impact on their ability to benefit from rehabilitation interventions. [Copyright &y& Elsevier]

The Launay–Slade Hallucination Scale (LSHS-R) (Launay & Slade, 1981; Bentall & Slade, 1985a) is a frequently used measure of predisposition to hallucinations in normal individuals. The current study administered the LSHS-R to a large sample of English-speaking undergraduate students (N=562). Principal component analyses identified three factors characterised as (1) vivid mental events, (2) hallucinations with a religious theme, and (3) auditory and visual hallucinatory experiences. The first factor refers to mental events where the experience is recognised as one''s own whereas the other two factors have in common that the experience is attributed to another source. The current factor structure is similar to the factors obtained by Levitan, Ward, Catts and Hemsley (1996) for participants with a psychiatric disorder and a history of auditory hallucinations, supporting the view that hallucinations exist on a continuum with normal experiences. [Copyright &y& Elsevier]

Cognitive impairment is a core feature of schizophrenia and impacts negatively the functioning of affected individuals. Cognitive decline correlates with aging, and is the primary cause of loss of independence and reduced quality of life. The klotho gene is a key modulator of aging, with expression deficiency resulting in premature aging, while overexpression extends lifespan and enhances cognition. A haplotype and functional human variant of the gene, KL-VS, increases expression and promotes longevity. KL-VS heterozygosity is associated with enhanced cognition and a larger volume of the right dorsolateral prefrontal cortex, a region involved in planning and decision-making, which is especially susceptible to shrinkage with age. We examined the effect of KL-VS heterozygosity on cognition in 497 schizophrenia patients and 316 healthy controls from the Western Australian Family Study of Schizophrenia (WAFSS) who had been comprehensively characterised by neurocognitive tests and classified into cognitively deficient (CD) and cognitively "spared" (CS) clusters. An older, cognitively normal population sample from the Health in Men Study (HIMS) was included to allow assessment of heterozygosity and memory in aged individuals. We show that heterozygosity is associated with better learning and memory in the younger WAFSS healthy controls but not in the aging HIMS sample. However, in schizophrenia patients, KL-VS has a selective effect on memory, with heterozygotes in CD and CS clusters performing worse than non-carriers. This effect was significant and more severe in the CD cluster, reinforcing the utility of subtyping patients into CD and CS clusters that may differ in their genetic underpinnings. [ABSTRACT FROM AUTHOR]

Individuals with autistic traits (measured with Autism-spectrum Quotient, AQ) often excel in detecting shapes hidden within complex structures (e.g. on the Embedded Figures Test, EFT). This facility has been attributed to either weaker global integration of scene elements or enhanced local processing, but ‘local’ and ‘global’ have various meanings in the literature. The function of specific global visual mechanisms involved in integrating contours, similar to EFT targets was examined. High AQ scorers produced enhanced performance on the EFT and an alternative Radial Frequency Search Task. Contrary to ‘generic’ interpretations of weaker global pooling, this group displayed stronger pooling of contour components that was correlated with search ability. This study therefore shows a global contour integration advantage in high AQ observers. [ABSTRACT FROM AUTHOR]

Abstract: The Embedded Figures Test (EFT) requires detecting a shape within a complex background and individuals with autism or high Autism-spectrum Quotient (AQ) scores are faster and more accurate on this task than controls. This research aimed to uncover the visual processes producing this difference. Previously we developed a search task using radial frequency (RF) patterns with controllable amounts of target/distracter overlap on which high AQ participants showed more efficient search than low AQ observers. The current study extended the design of this search task by adding two lines which traverse the display on random paths sometimes intersecting target/distracters, other times passing between them. As with the EFT, these lines segment and group the display in ways that are task irrelevant. We tested two new groups of observers and found that while RF search was slowed by the addition of segmenting lines for both groups, the high AQ group retained a consistent search advantage (reflected in a shallower gradient for reaction time as a function of set size) over the low AQ group. Further, the high AQ group were significantly faster and more accurate on the EFT compared to the low AQ group. That is, the results from the present RF search task demonstrate that segmentation and grouping created by intersecting lines does not further differentiate the groups and is therefore unlikely to be a critical factor underlying the EFT performance difference. However, once again, we found that superior EFT performance was associated with shallower gradients on the RF search task. [ABSTRACT FROM AUTHOR]

Abstract: The Embedded Figure Test (EFT) requires locating a simple shape embedded within a background of overlapping target-irrelevant scene elements. Observers with autism, or those with high levels of autistic-like traits, typically outperform matched comparison groups on the EFT. This research investigated the critical visual properties which give rise to this improved performance. The EFT is a search task and so here a radial frequency (RF) search task was created to directly explore efficacy of visual search and also the influence of element overlap on performance. In all conditions, the task was to detect whether the target RF3 (a triangular shape chosen for its visual properties) was present among a number of distracter RF4 (a square shape) patterns. The conditions employed were: ‘singles’, where all the patterns were spatially discrete, ‘pairs’, where two overlapping elements formed each cluster, and ‘quads’, comprising four overlapping elements per cluster. Compared to students scoring low on the Autism Spectrum Quotient (AQ; n =27), those scoring high on the AQ (n =23) were faster on the EFT and also significantly less influenced by increasing set size of the stimulus array in all RF search task conditions. However, the group difference in RF search performance was unaffected by the amount of stimulus overlap. Thus a simple search task is sufficient to detect a performance advantage associated with higher levels of autistic traits and has the advantages of a solid footing in visual theory and being readily repeatable for the purpose of assessing performance variability and change with interventions. [Copyright &y& Elsevier]