中国丧亲个体社会支持体验的质性研究

本研究通过对28位丧亲者进行深度访谈,使用解释现象学分析法对质性数据进行分析,探索中国丧亲个体的社会支持体验。结果显示,丧亲社会支持的内容包括后事处理、情感支持、生活恢复帮助,经济与物资支持等。支持来源除家人和朋友之外,还包括同事、相同经历者,以及相关机构等。社会支持通过调节情绪、改变认知等方式促进个体对丧亲的适应。本研究结果为最新丧亲社会支持模型提供了支持,同时也反映出中国社会对丧亲人群的社会支持特色。     

Study of behavioural and neural bases of visuo‐spatial working memory with an fMRI paradigm based on an n‐back task

The goal of this study was to propose a new functional magnetic resonance imaging (fMRI) paradigm using a language‐free adaptation of a 2‐back working memory task to avoid cultural and educational bias. We additionally provide an index of the validity of the proposed paradigm and test whether the experimental task discriminates the behavioural performances of healthy participants from those of individuals with working memory deficits. Ten healthy participants and nine patients presenting working memory (WM) deficits due to acquired brain injury (ABI) performed the developed task. To inspect whether the paradigm activates brain areas typically involved in visual working memory (VWM), brain activation of the healthy participants was assessed with fMRIs. To examine the task's capacity to discriminate behavioural data, performances of the healthy participants in the task were compared with those of ABI patients. Data were analysed with GLM‐based random effects procedures and t‐tests. We found an increase of the BOLD signal in the specialized areas of VWM. Concerning behavioural performances, healthy participants showed the predicted pattern of more hits, less omissions and a tendency for fewer false alarms, more self‐corrected responses, and faster reaction times, when compared with subjects presenting WM impairments. The results suggest that this task activates brain areas involved in VWM and discriminates behavioural performances of clinical and non‐clinical groups. It can thus be used as a research methodology for behavioural and neuroimaging studies of VWM in block‐design paradigms.     

Extraversion modulates functional connectivity hubs of resting‐state brain networks

Personality dimension extraversion describes individual differences in social behaviour and socio‐emotional functioning. The intrinsic functional connectivity patterns of the brain are reportedly associated with extraversion. However, whether or not extraversion is associated with functional hubs warrants clarification. Functional hubs are involved in the rapid integration of neural processing, and their dysfunction contributes to the development of neuropsychiatric disorders. In this study, we employed the functional connectivity density (FCD) method for the first time to distinguish the energy‐efficient hubs associated with extraversion. The resting‐state functional magnetic resonance imaging data of 71 healthy subjects were used in the analysis. Short‐range FCD was positively correlated with extraversion in the left cuneus, revealing a link between the local functional activity of this region and extraversion in risk‐taking. Long‐range FCD was negatively correlated with extraversion in the right superior frontal gyrus and the inferior frontal gyrus. Seed‐based resting‐state functional connectivity (RSFC) analyses revealed that a decreased long‐range FCD in individuals with high extraversion scores showed a low long‐range functional connectivity pattern between the medial and dorsolateral prefrontal cortex, middle temporal gyrus, and anterior cingulate cortex. This result suggests that decreased RSFC patterns are responsible for self‐esteem, self‐evaluation, and inhibitory behaviour system that account for the modulation and shaping of extraversion. Overall, our results emphasize specific brain hubs, and reveal long‐range functional connections in relation to extraversion, thereby providing a neurobiological basis of extraversion.     

Neural substrates of the ‘low‐level’ system for speech articulation: Evidence from primary opercular syndrome

We describe a patient with progressive disorder of speech, without language impairment (opercular syndrome). Morphometric analysis confirmed asymmetric volume reduction of the precentral areas (>left). Diffusion imaging showed significant white matter changes in the left frontal lobe, with specific involvement of the left corticobulbar tract and connections between supplementary/pre‐supplementary motor areas and the frontal operculum (frontal aslant tract). We suggest that the organization of expressive language includes a ‘low level’ motor system principally distributed in the left hemisphere that shows specific susceptibility to neurodegeneration, distinct from neural systems subtending praxic, and cognitive aspects of language.     

The joint flanker effect and the joint Simon effect: On the comparability of processes underlying joint compatibility effects

Previous studies observed compatibility effects in different interference paradigms such as the Simon and flanker task even when the task was distributed across two co-actors. In both Simon and flanker tasks, performance is improved in compatible trials relative to incompatible trials if one actor works on the task alone as well as if two co-actors share the task. These findings have been taken to indicate that actors automatically co-represent their co-actor’s task. However, recent research on the joint Simon and joint flanker effect suggests alternative non-social interpretations. To which degree both joint effects are driven by the same underlying processes is the question of the present study, and it was scrutinized by manipulating the visibility of the co-actor. While the joint Simon effect was not affected by the visibility of the co-actor, the joint flanker effect was reduced when participants did not see their co-actors but knew where the co-actors were seated. These findings provide further evidence for a spatial interpretation of the joint Simon effect. In contrast to recent claims, however, we propose a new explanation of the joint flanker effect that attributes the effect to an impairment in the focusing of spatial attention contingent on the visibility of the co-actor.     

Introducing a new age-and-cognition-sensitive measurement for assessing spatial orientation using a landmark-less virtual reality navigational task

Age-related impairments during spatial navigation have been widely reported in egocentric and allocentric paradigms. However, the effect of age on more specific navigational components such as the ability to drive or update directional information has not received enough attention. In this study we investigated the effect of age on spatial updating of a visual target after a series of whole–body rotations and transitions using a novel landmark-less virtual reality (VR) environment. Moreover, a significant number of previous studies focused on measures susceptible to a general decline in motor skills such as the spent time navigating, the distance traversed. The current paper proposes a new compound spatial measure to assess navigational performance, examines its reliability and compares its power with those of the measures of duration and traversed distance in predicting participants' age and cognitive groups assessed by Montreal Cognitive Assessment (MoCA) scores. Using data from 319 adults (20–83 years), our results confirm the reliability, the age sensitivity, and the cognitive validity of the designed spatial measure as well as its superiority to the measures of duration and traversed distance in predicting age and MoCA score. In addition, the results show the significant effect of age cognitive status on spatial updating.     

Distance stability analysis in multidimensional scaling using the jackknife method

Stability or sensitivity analysis is an important topic in data analysis that has received little attention in the application of multidimensional scaling (MDS), for which the only available approaches are given in terms of a coordinate‐based analytical jackknife methodology. Although in MDS the prime interest is in assessing the stability of the points in the configuration, this methodology may be influenced by imprecisions resulting from the inherently necessary Procrustes method. This paper proposes an analytical distance‐based jackknife procedure to study stability and cross‐validation in MDS in terms of the jackknife distances, which is not influenced by the Procrustes method. For each object, the corresponding jackknife estimated points are considered as naturally clustered points, and stability and cross‐validation are analysed in terms of the MDS distances arising from the jackknife procedure, on the basis of a weighted cluster‐MDS algorithm. A jackknife‐relevant configuration is also proposed for cross‐validation in terms of coordinates, in a cluster‐MDS framework.     

Developing new online calibration methods for multidimensional computerized adaptive testing

Multidimensional computerized adaptive testing (MCAT) has received increasing attention over the past few years in educational measurement. Like all other formats of CAT, item replenishment is an essential part of MCAT for its item bank maintenance and management, which governs retiring overexposed or obsolete items over time and replacing them with new ones. Moreover, calibration precision of the new items will directly affect the estimation accuracy of examinees’ ability vectors. In unidimensional CAT (UCAT) and cognitive diagnostic CAT, online calibration techniques have been developed to effectively calibrate new items. However, there has been very little discussion of online calibration in MCAT in the literature. Thus, this paper proposes new online calibration methods for MCAT based upon some popular methods used in UCAT. Three representative methods, Method A, the ‘one EM cycle’ method and the ‘multiple EM cycles’ method, are generalized to MCAT. Three simulation studies were conducted to compare the three new methods by manipulating three factors (test length, item bank design, and level of correlation between coordinate dimensions). The results showed that all the new methods were able to recover the item parameters accurately, and the adaptive online calibration designs showed some improvements compared to the random design under most conditions.