State-Space Analysis of Working Memory in Schizophrenia: An FBIRN Study

The neural correlates of working memory (WM) in schizophrenia (SZ) have been extensively studied using the multisite fMRI data acquired by the Functional Biomedical Informatics Research Network (fBIRN) consortium. Although univariate and multivariate analysis methods have been variously employed to localize brain responses under differing task conditions, important hypotheses regarding the representation of mental processes in the spatio-temporal patterns of neural recruitment and the differential organization of these mental processes in patients versus controls have not been addressed in this context. This paper uses a multivariate state-space model (SSM) to analyze the differential representation and organization of mental processes of controls and patients performing the Sternberg Item Recognition Paradigm (SIRP) WM task. The SSM is able to not only predict the mental state of the subject from the data, but also yield estimates of the spatial distribution and temporal ordering of neural activity, along with estimates of the hemodynamic response. The dynamical Bayesian modeling approach used in this study was able to find significant differences between the predictability and organization of the working memory processes of SZ patients versus healthy subjects. Prediction of some stimulus types from imaging data in the SZ group was significantly lower than controls, reflecting a greater level of disorganization/heterogeneity of their mental processes. Moreover, the changes in accuracy of predicting the mental state of the subject with respect to parametric modulations, such as memory load and task duration, may have important implications on the neurocognitive models for WM processes in both SZ and healthy adults. Additionally, the SSM was used to compare the spatio-temporal patterns of mental activity across subjects, in a holistic fashion and to derive a low-dimensional representation space for the SIRP task, in which subjects were found to cluster according to their diagnosis.     

Audiovisual identity perception from naturally-varying stimuli is driven by visual information

Identity perception often takes place in multimodal settings, where perceivers have access to both visual (face) and auditory (voice) information. Despite this, identity perception is usually studied in unimodal contexts, where face and voice identity perception are modelled independently from one another. In this study, we asked whether and how much auditory and visual information contribute to audiovisual identity perception from naturally-varying stimuli. In a between-subjects design, participants completed an identity sorting task with either dynamic video-only, audio-only or dynamic audiovisual stimuli. In this task, participants were asked to sort multiple, naturally-varying stimuli from three different people by perceived identity. We found that identity perception was more accurate for video-only and audiovisual stimuli compared with audio-only stimuli. Interestingly, there was no difference in accuracy between video-only and audiovisual stimuli. Auditory information nonetheless played a role alongside visual information as audiovisual identity judgements per stimulus could be predicted from both auditory and visual identity judgements, respectively. While the relationship was stronger for visual information and audiovisual information, auditory information still uniquely explained a significant portion of the variance in audiovisual identity judgements. Our findings thus align with previous theoretical and empirical work that proposes that, compared with faces, voices are an important but relatively less salient and a weaker cue to identity perception. We expand on this work to show that, at least in the context of this study, having access to voices in addition to faces does not result in better identity perception accuracy.     

Relationships between quality of life,spiritual well-being,and psychological adjustment styles for people living with leukaemia: An exploratory study

This paper reports on the relationships between quality of life, spiritual well-being, and psychological adjustment styles for people living with leukaemia. Participants were 40 adults (26 women and 14 men) aged between 22 and 80 years living with acute or chronic leukaemia in Western Australia. Participants completed three scales measuring spiritual well-being (FACIT-Sp-12-C Version 4; Cella, 1997 Cella, D. 1997. “Functional Assessment of Chronic Illness Therapy (FACIT) Manual, Version 4”. In Chicago: Center on Outcomes Research and Education CORE, Evanston, Chicago: Northwestern Healthcare and Northwestern University.  [Google Scholar]), psychological adjustment styles (MAC; Watson, Greer, & Bliss, 1989 Watson, M, Greer, S and Bliss, JM. 1989. Mental Adjustment to Cancer (MAC) Scale: User's manual, London: CRC Psychological Medicine Research Group The Royal Marsden Hospital.  [Google Scholar]), and quality of life (FACIT-G; Cella, 1997 Cella, D. 1997. “Functional Assessment of Chronic Illness Therapy (FACIT) Manual, Version 4”. In Chicago: Center on Outcomes Research and Education CORE, Evanston, Chicago: Northwestern Healthcare and Northwestern University.  [Google Scholar]). No differences were found between the men and women participants, with the exception of the anxious preoccupation adjustment style. Significant positive correlations were found between spiritual well-being and quality of life (r?=?0.72, p?=?<0.01), and between fighting spirit and both spiritual well-being (r?=?0.55, p?<?0.01) and quality of life (r?=?0.67, p?<?0.01). Spiritual well-being and quality of life were both significantly negatively correlated with hopelessness/helplessness, fatalism, and anxious preoccupation, suggesting that people who are able to find meaning in their illness are more likely to utilize functional psychological adjustment styles. A stepwise multiple regression revealed that spiritual well-being was most strongly associated with quality of life for people living with leukaemia, followed by a fighting spirit; together, these accounted for 61% of the variance in quality of life scores. Thus, having a reason for living, making life more productive, finding comfort in faith or spiritual beliefs, being determined to control the environment, and feeling a sense of meaning, peace, harmony, purpose, and comfortable in oneself are factors that contribute to a better quality of life among patients with leukaemia. Strengths, limitations, and implications of the findings are discussed.     

General Attitudes Towards Marriage Scale: Psychometric Properties in Malaysian Adolescents of Divorced Families

Attitudes towards marriage in adolescence may influence the relationship quality in later years. There exist many measures of attitudes towards marriage which were validated among adolescents from two-parent family in the Western context. There is a need to validate measure of attitudes towards marriage in different countries. This study examined the psychometric properties of the Malay version of general attitudes towards marriage scale in a sample of 480 adolescents from divorced families in Malaysia. Exploratory factor analysis yielded a two-factor structure of general attitudes towards marriage scale, which explained for 60% of the variance. Additionally, the two-factor structure of general attitudes towards marriage scale demonstrated good fit to data in the confirmatory factor analysis (non-normed fit index?=?.941, comparative fit index?=?.958, root mean square error of estimation?=?.087, and χ ²/df?=?4.615). Overall, the general attitudes towards marriage scale exhibited good internal consistency (α?=?.901), which supports the reliability of the instrument. The significant relationships between general attitudes towards marriage scale and other constructs also provided evidences to the convergent validity (r?=?.761, p?<?.001 with intent to marry, r?=??.170, p?<?.001 with overt inter-parental conflict, and r?=?.523, p?<?.001 with mother–adolescent relationship). Significant gender difference was found in the report of general attitudes towards marriage scale (t?=??2.265, p?<?.05). Thus, the translated general attitudes towards marriage scale is a reliable, valid, and practical instrument to measure attitudes towards marriage among Malaysian adolescents in divorced family setting.     

Using the Depression Anxiety Stress Scale 21 (DASS‐21) across cultures

The DASS‐21 is a well‐established instrument for measuring depression, anxiety, and stress with good reliability and validity reported from Hispanic American, British, and Australian adults. However, the lack of appropriate validation among Asian populations continues to pose concerns over the use of DASS‐21 in Asian samples. Cultural variation may influence the individual's experience and emotional expression. Thus, when researchers and practitioners employ Western‐based assessments with Asian populations by directly translating them without an appropriate validation, the process can be challenging. We conducted a series of rigorous statistical tests and minimized any potential confounds from the demographic information. Following factor analyses, we performed multigroup analysis across six nations to demonstrate consistency of our findings. The advantages of this revised DASS‐18 stress scale are twofold. First, it possesses fewer items, which results in a cleaner factorial structure. Second, it has a smaller interfactor correlation. With these justifications, the revised DASS‐18 stress scale is potentially more suitable for Asian populations. Nonetheless, given limitations, findings should be considered preliminary.