Gait and risk of falls associated with frontal cognitive functions at different stages of Alzheimer's disease

ABSTRACT The decline in frontal cognitive functions contributes to alterations of gait and increases the risk of falls in patients with dementia, a category which included Alzheimer's disease (AD). The objective of the present study was to compare the gait parameters and the risk of falls among patients at different stages of AD, and to relate these variables with cognitive functions. This is a cross-sectional study with 23 patients with mild and moderate AD. The Clinical Dementia Rating was used to classify the dementia severity. The kinematic parameters of gait (cadence, stride length, and stride speed) were analyzed under two conditions: (a) single task (free gait) and (b) dual task (walking and counting down). The risk of falls was evaluated using the Timed Up-and-Go test. The frontal cognitive functions were evaluated using the Frontal Assessment Battery (FAB), the Clock Drawing Test (CDT) and the Symbol Search Subtest. The patients who were at the moderate stage suffered reduced performance in their stride length and stride speed in the single task and had made more counting errors in the dual task and still had a higher fall risk. Both the mild and the moderate patients exhibited significant decreases in stride length, stride speed and cadence in the dual task. Was detected a significant correlation between CDT, FAB, and stride speed in the dual task condition. We also found a significant correlation between subtest Similarities, FAB and cadence in the dual task condition. The dual task produced changes in the kinematic parameters of gait for the mild and moderate AD patients and the gait alterations are related to frontal cognitive functions, particularly executive functions.     

Reducing the Floor Effect in the SF-6D: A Feasibility Study

The SF-6D suffers from a floor effect where for patient groups in severe health a significant number of patients report the lowest level of health possible for some dimensions, meaning the SF-6D cannot capture a deterioration in health for these patients. This paper presents a feasibility study aimed at reducing this floor effect. A modified SF-6D classification system was proposed that incorporated an additional level in each of the physical functioning and role limitations dimensions. The modified classification system was valued by a Portuguese general population sample (n = 140) using the Portuguese SF-6D protocol. A sample of 82 health states were valued and several regression models were estimated to produce preference weights to predict health state values for all states defined by the modified classification system. Estimations at the individual level were performed using 950 health state valuations. Models were analyzed in terms of logical consistency of coefficients, overall fit and predictive ability and were compared to Portuguese SF-6D models. The additional severity levels included in the modified classification system have significant decrements in health state values. These additional severity levels do not significantly impact on the modelled preference weights (the regression coefficients) of other levels across all dimensions. This feasibility study modified the SF-6D to reduce the floor effect. This study presents one option and further research in this area is encouraged.     

Investigating Constituent Order Change With Elicited Pantomime: A Functional Account of SVO Emergence

One of the most basic functions of human language is to convey who did what to whom. In the world's languages, the order of these three constituents (subject [S], verb [V], and object [O]) is uneven, with SOV and SVO being most common. Recent experiments using experimentally elicited pantomime provide a possible explanation of the prevalence of SOV, but extant explanations for the prevalence of SVO could benefit from further empirical support. Here, we test whether SVO might emerge because (a) SOV is not well suited for describing reversible events (a woman pushing a boy) and (b) pressures to be efficient and mention subjects before objects conspire to rule out many other alternatives. We tested this by asking participants to describe reversible and non‐reversible events in pantomime, and we instructed some participants to be consistent in the form of their gestures and to teach them to the experimenter. These manipulations led to the emergence of SVO in speakers of both English (SVO) and Turkish (SOV).     

Diminished joint coordination with aging leads to more variable hand paths

Differences in joint coordination between arms and due to aging were studied in healthy young and older adults reaching to either a fixed, central target or to the same target when it could unexpectedly change location after reach initiation. Joint coordination was investigated by artificially removing the covariation of each joint’s motions with other joints’ motions. Uncontrolled manifold analysis was used to partition joint configuration variance into variance reflecting motor abundance (V_UCM) and variance causing hand path variability (V_ORT). The extent to which V_ORT, related to the consistency of the hand path, increased after removing a joint’s covariation indicated the strength of its coordination with other joints. Young adults exhibited stronger indices of joint coordination, evidenced by a larger increase in V_ORT after removing joint covariation than for older adults. This effect was more striking for the dominant right compared to the left arm for young adults, but not for older adults, especially with target uncertainty. The results indicate that interjoint coordination in young adults leads to less hand path variability compared to older adults.     

Portuguese adaptation of the Gudjonsson Suggestibility Scales (GSS1 and GSS2): Empirical findings

In study 1 (n = 51, M_age = 21.4 years, SD = 5.7), the validity of the Portuguese adaptation of the Gudjonsson Suggestibility Scales ( Pires, 2011) was shown through the comparison of means of the original ( Gudjonsson, 1997) and the translated scales and the analysis of the correlations between the GSS1 and GSS2 scores. The relationships between interrogative suggestibility and the big five were also addressed and the results point to independence between suggestibility and personality, which is in line with Polczyk’s findings (2005). Study 2 (n = 87, M_age = 48.9 years, SD = 20.7) explored the relationships among interrogative suggestibility, the state–trait anxiety and demographic variables (i.e., age and gender). There were no significant relationships between anxiety and suggestibility. These results are in line with other studies that point to a lack of relationship between suggestibility and anxiety in normal samples (  and ). As for the relationships between age and interrogative suggestibility, ANCOVA confirmed that the increased suggestibility in old age was not due to age differences but rather to the limited memory capacity of the older adults group. There were no significant gender differences in the GSS1 subscales.     

Strategic Numeracy: Self-Serving Reasoning About Health Statistics

This research shows that the same people who appear to have low numerical competence when analyzing personally irrelevant health-related numerical information are able to overcome their reasoning shortcomings and make better judgments when they are shown equivalent information that is personally relevant, and when only a sophisticated kind of reasoning enables them to interpret this information in a favorable way. The fact that people can engage in poorer or more sophisticated numerical reasoning depending on whether that reasoning produces favorable or unfavorable conclusions has implications both for the concept of numeracy as an individual-difference variable and for health communication.     

Acquired Procedural Dyscalculia Associated to a Left Parietal Lesion in a Child

We report the case of an 11-year-old boy who developed an anarithmetia in association with a left temporo-parietal tumor. His oral and written language were normal as well as his ability to judge magnitudes, process numbers, read operation signs and retrieve number facts. He had a specific difficulty in performing the procedures of subtraction, especially when it involved borrowing. These skills had been mastered before the present illness. This case shows that the components of calculation can be dissociated by brain lesions sustained during childhood, while arithmetic abilities are being acquired, thus reinforcing findings from developmental dyscalculias, that suggest a modular organisation of those skills during development.     

How Children Experience the Assets that Support their Learning

The study, on which this article is based, explored the ways in which primary school children in an urban (city centre) setting experience the assets and resources that support their learning. The researchers used a qualitative phenomenological research design incorporating an interpretive and constructivist perspective. The study was conducted in a primary school in Tshwane, Gauteng province, South Africa. The participants were eight African female participants in Grades 5–7 who had overcome extrinsic barriers to learning. They participated in a focus group discussion during which the relevant and natural units of significant statements were listed (horizontalisation) and structured into central clusters of meanings. Textural themes (what) and structural themes (how) were identified. The study found that human resource assets were central to the process of connecting a variety of assets that supported learning. The study also found a significant compound effect of assets, for example increased connected assets had a noteworthy additional positive effect on learning support. The identified assets interrelatedly mobilised other assets (textural findings) on one of five levels (structural findings: physical assets, social assets, safety assets, esteem assets and self-actualisation) in various systems and contexts that contribute to learning support. This article elaborates on these findings.