Duration estimation and the phonological loop: Articulatory suppression and irrelevant sounds

Clock-based theories of time estimation propose that clock pulses are accumulated in working memory. Although these theories do not constrain the form of the memory trace, evidence reported in the literature suggests that active manipulation of a verbal trace may be involved. Four experiments are reported in which participants reproduced or verbally estimated short durations (up to a few seconds) either in a single-task condition or in a condition with a phonological load. Experiments 1, 2 and 4 showed that both interval reproduction and verbal estimation were impaired under concurrent articulatory suppression in comparison to a timing only control condition. Neither irrelevant speech (Experiments 1-3) nor irrelevant tones and music (Experiment 3) impaired timing performance. These findings are taken to show that time estimation is mediated by phonological working memory and the involvement of an active articulatory rehearsal process.     

Mental fatigue disturbs local processing more than global processing

Focusing of attention is influenced by external features such as the presence of global or local target stimuli, but also by motivation and mood states. In the current study, we examined whether working on cognitively demanding tasks for 2 h, which induces mental fatigue, subsequently had a differential effect on global and local processing. The results showed that, compared to non-fatigued participants, fatigued participants particularly displayed compromised local processing. This indicates that mental fatigue may also manifest itself as effects on attentional focusing. The findings of this study are in line with recent ideas about the nature of fatigue-related cognitive deficits, implying disturbances in the control over attention and behaviour.     

Use of the Hayling task to measure inhibition of prepotent responses in normal aging and Alzheimer's disease

This study measures the effect of Alzheimer's disease (AD) and normal aging on the inhibition of prepotent responses. AD patients, normal aged controls, and young subjects were tested with the Hayling task, which measures the ability to inhibit a semantically constrained response, and with the Stroop procedure. AD patients showed a severe deficit in both error rates and response time on the Hayling task. Inhibition was also impaired on the Stroop procedure, both when using raw performance and when using an inhibition score that controlled for reading and naming speed. Normal aged participants showed modest impairment relative to young controls on both tests. Examination of individual performance in AD patients indicated that the impairment was found in most patients on the Hayling test but in only a subgroup of patients on the Stroop test.     

Mere exposure effect: A consequence of direct and indirect fluency-preference links

In three experiments, picture quality between test items was manipulated to examine whether subjects' expectations about the fluency normally associated with these different stimuli might influence the effects of fluency on preference or familiarity-based recognition responses. The results showed that fluency due to pre-exposure influenced responses less when objects were presented with high picture quality, suggesting that attributions of fluency to preference and familiarity are adjusted according to expectations about the different test pictures. However, this expectations influence depended on subjects' awareness of these different quality levels. Indeed, imperceptible differences seemed not to induce expectations about the test item fluency. In this context, fluency due to both picture quality and pre-exposure influenced direct responses. Conversely, obvious, and noticed, differences in test picture quality did no affect responses, suggesting that expectations moderated attributions of fluency only when fluency normally associated with these different stimuli was perceptible but difficult to assess.     

Does marriage protect older people from distress? The role of equity and recency of bereavement

The association between marital status and distress was examined in a largely neglected group, namely older people (65 and older; N = 1,649). In this 2-wave study, married persons were less distressed than single persons, but perceived equity within the marriage and recency of bereavement qualified these findings. Married persons who felt inequitably treated were more distressed than persons who had always been single. Married persons reported less distress than recently (= 2 years ago) widowed persons, but only equitably treated married persons reported less distress than persons widowed for more than 2 years. Increased distress between the 2 waves occurred in recently widowed persons, and there was a decrease in distress in persons who were widowed shortly before the 1st wave. No gender effects were found.     

Differential involvement of hippocampal calcineurin during learning and reversal learning in a Y-maze task

The regulation and function of the calcium-dependent phosphatase calcineurin (CaN, protein phosphatase 2B) in learning and memory remain unclear, although recent work indicates that CaN may play a differential role in training and reversal training. To gain more insight into the involvement of CaN in these two types of learning, hippocampal CaN activity, protein levels, and expression patterns were studied in mice subjected to a reference memory version of the Y-maze task. We show that (1) training but not habituation induces a decrease in cytosolic CaN activity, (2) the recovery of cytosolic CaN activity is reversal training specific and does not reflect normal restoration of basal levels unrelated to subsequent learning, (3) cytosolic protein levels for the catalytic subunit of CaN (CaNA) are decreased at the early phase of training, but not at the early phase of reversal training, (4) CaNA immunoreactivity in the dorsal hippocampus is enhanced in the CA1 and CA3 area (but not in the dentate gyrus [DG] or subiculum [SUB]) only during reversal training. These findings indicate that memory formation is accompanied by reduced CaN activity, whereas adapting to changes in a familiar environment is accompanied by restored CaN activity. Moreover, reversal training selectively affects hippocampal CA3 and CA1 regions, suggesting a specific function of these hippocampal subregions in reversal learning.     

The Stroop color-word test: influence of age, sex, and education; and normative data for a large sample across the adult age range

The Stroop Color-Word Test was administered to 1,856 cognitively screened, healthy Dutch speaking participants aged 24 to 81 years. The effects of age, gender, and education on Stroop test performance were investigated to adequately stratify the normative data. The results showed that especially the speed-dependent Stroop scores (time to complete a subtest), rather than the accuracy measures (the errors made per Stroop sub-task), were profoundly affected by the demographic variables. In addition to the main effects of the demographic variables, an Age Low Level of Education interaction was found for the Error III and the Stroop Interference scores. This suggests that executive function, as measured by the Stroop test, declines with age and that the decline is more pronounced in people with a low level of education. This is consistent with the reserve hypothesis of brain aging (i.e., that education generates reserve capacity against the damaging effects of aging on brain functions). Normative Stroop data were established using both a regression-based and traditional approach, and the appropriateness of both methods for generating normative data is discussed.     

Measuring health-related stigma--a literature review

Stigma related to chronic health conditions such as HIV/AIDS, leprosy, tuberculosis, mental illness and epilepsy is a global phenomenon with a severe impact on individuals and their families, and on the effectiveness of public health programmes. To compare stigma measurement in different disciplines, a literature review was conducted. References were obtained through a search of literature databases and through examining relevant bibliographies. Sixty-three papers were selected that addressed the issue of measurement of stigma or related constructs and that contained a sample of the instrument or items used. Five unpublished studies were also included in the review. The aspects of health-related stigma used for assessment can be grouped in five categories. First, the experience of actual discrimination and/or participation restrictions on the part of the person affected; second, attitudes towards the people affected; third, perceived or felt stigma; fourth, self or internalized stigma; and fifth, discriminatory and stigmatizing practices in (health) services, legislation, media and educational materials. Within each of these areas, different research methods have been used, including questionnaires, qualitative methods, indicators and scales. The characteristics of the instruments considered most promising are described and compared. The purpose of stigma assessment is to increase our understanding of stigma and its determinants and dynamics, to determine its extent or severity in a given setting or target group and to monitor changes in stigma over time. The conclusions from this review are that (a) the consequences of stigma are remarkably similar in different health conditions, cultures and public health programmes; (b) many instruments have been developed to assess the intensity and qualities of stigma, but often these have been condition-specific; and (c) development of generic instruments to assess health-related stigma may be possible. To achieve this aim, existing instruments should be further validated, developed or adapted for generic use, where possible.