Input/output switch in bilingual code switching

Chinese-English bilinguals were asked to read a passage with spontaneous bilingual code switchings, compared with a unilingual Chinese translation of the passage, a unilingual English translation, a translation with random switchings, and a translation with only nouns switched into English. There was no difference between the reading speed for the passage with natural switchings and the unilingual Chinese passage, thus questioning the need to postulate a bilingual imput/output switch. The speed for reading passages with artificial switchings was slower. In a translation task, the naturally switched items required less time in Chinese-to-English translations compared with English-to-Chinese translations. This indicates that in natural code switchings, the English lexical items produced were more available, even though English is generally the weaker language.     

Factor structure of the Chinese version of the Geriatric Depression Scale

Depression is common in patients following stroke and has been found to be related to the degree of functional disability, recovery and engagement in rehabilitation. Consequently, screening for depression is crucial in this group in order to facilitate the delivery of appropriate psychological support. The current study sought to determine key psychometric properties of the Chinese version of the Geriatric Depression Scale (GDS) in this group. Three versions of the GDS were evaluated, these being the 30-item original measure (GDS-30), the short-form version comprising 15 items (GDS-SF) and a recently developed innovative four-item version (GDS-4). Confirmatory factor analysis revealed the GDS-30 and GDS-SF to offer an acceptable fit to data suggesting utility of these measures for screening. However, the GDS-4 offered a poor fit to the data, suggesting this measure was an inadequate measure of depression in this clinical group. Further, though GDS-30 and GDS-SF measures revealed good internal consistency, the performance of the GDS-4 was marginal. However, all GDS-derived measures demonstrated excellent convergent and divergent validity. It is concluded that the GDS-30 is a useful and appropriate screening instrument in this group. Further, the GDS-SF shows promise in terms of development as a multidimensional measure of depression that may have predictive and outcome monitoring potential. The psychometric shortcomings of the GDS-4 strongly suggest that this measure is unsuitable for screening in this clinical group.     

Measures of dynamic stability: Detecting differences between walking overground and on a compliant surface

Numerous measures of dynamic stability have been proposed to gauge fall risk in the elderly, including stride interval variability and variability of the center of mass. However, these measures have been deemed inadequate because they do not take into account temporal information. Therefore, research on the measurement of dynamic stability has turned to other analysis methods such as stride interval dynamics and the maximum Lyapunov exponent. Stride interval dynamics reflect the statistical persistence of an individual’s stride interval time series and the Lyapunov exponent quantifies local dynamic stability – the sensitivity of the system to infinitesimal perturbations. In this study, we compare the ability of these measurement tools to detect changes between overground and compliant-surface walking, a condition known to affect stability, to determine their aptness as measures of dynamic stability. Fourteen able-bodied participants completed three 15 min walks, two overground and one on a compliant surface. Our results show that the Lyapunov exponent may be more sensitive to gait changes than stride interval dynamics and gait variability measures.     

Ideological Orientation and Political Transition in Hong Kong: Confidence in the Future

In the two-component model of ideological orientation, a person's ideological position is jointly influenced by attitudinal and affective components. The present study adopted this conceptual model to predict confidence in the future of Hong Kong. Questionnaire responses were collected from 395 adults (56.8% men and 43.2% women) in Hong Kong in April 1995, some 2 years before its transfer from British to Chinese control. The results show that the level of confidence in Hong Kong was related to both attitudinal and affective identification with Hong Kong and China. These findings suggest that the transfer of government may have brought to the surface a collision of the divergent political cultures of Hong Kong and mainland China, resulting in two antagonistic political orientations that predicted confidence in the future of Hong Kong.     

Short-term music training enhances verbal intelligence and executive function

Researchers have designed training methods that can be used to improve mental health and to test the efficacy of education programs. However, few studies have demonstrated broad transfer from such training to performance on untrained cognitive activities. Here we report the effects of two interactive computerized training programs developed for preschool children: one for music and one for visual art. After only 20 days of training, only children in the music group exhibited enhanced performance on a measure of verbal intelligence, with 90% of the sample showing this improvement. These improvements in verbal intelligence were positively correlated with changes in functional brain plasticity during an executive-function task. Our findings demonstrate that transfer of a high-level cognitive skill is possible in early childhood.     

Departures from sensible play in computer blackjack

Gambling has been viewed as irrational, and even though blackjack offers rational strategies (i.e., Basic [E. Thorp, 1966] and card counting), people exhibit departures from rationality (e.g., "Never Bust" strategies). To determine whether departures from rational behavior reflect ignorance or fatigue, university students were provided with on-line Basic advice while playing a simplified computer blackjack. Although the on-line advice initially affected the totals these players sat on, it was eventually discarded for higher risk strategies. Irrational play did not reflect ignorance or fatigue and was not necessarily conservative. Real fluctuations of odds in blackjack may lead to situations in which Basic is not perceived by players as effective. Because Basic is not a personalized strategy, it seems less likely to be maintained in the face of losses. Players were more optimistic that they might win when utilizing their personalized strategies.     

Working memory deficits in transgenic rats overexpressing human adenosine A2A receptors in the brain

Adenosine receptors in the central nervous system have been implicated in the modulation of different behavioural patterns and cognitive functions although the specific role of A(2A) receptor (A(2A)R) subtype in learning and memory is still unclear. In the present work we establish a novel transgenic rat strain, TGR(NSEhA2A), overexpressing adenosine A(2A)Rs mainly in the cerebral cortex, the hippocampal formation, and the cerebellum. Thereafter, we explore the relevance of this A(2A)Rs overexpression for learning and memory function. Animals were behaviourally assessed in several learning and memory tasks (6-arms radial tunnel maze, T-maze, object recognition, and several Morris water maze paradigms) and other tests for spontaneous motor activity (open field, hexagonal tunnel maze) and anxiety (plus maze) as modification of these behaviours may interfere with the assessment of cognitive function. Neither motor performance and emotional/anxious-like behaviours were altered by overexpression of A(2A)Rs. TGR(NSEhA2A) showed normal hippocampal-dependent learning of spatial reference memory. However, they presented working memory deficits as detected by performance of constant errors in the blind arms of the 6 arm radial tunnel maze, reduced recognition of a novel object and a lack of learning improvement over four trials on the same day which was not observed over consecutive days in a repeated acquisition paradigm in the Morris water maze. Given the interdependence between adenosinic and dopaminergic function, the present results render the novel TGR(NSEhA2A) as a putative animal model for the working memory deficits and cognitive disruptions related to overstimulation of cortical A(2A)Rs or to dopaminergic prefrontal dysfunction as seen in schizophrenic or Parkinson's disease patients.