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.     

Hand gestures and perceived influence in small group interaction

A laboratory study was carried out to establish the relative importance of verbal and gestural behavior, as well as their interaction, for perceived social influence in more or less competitive small groups. Forty women (psychology students) participated in leaderless small group discussions of different sizes (four-member and eight-member): at the end, each member rated the perceived influence in decision-making of every other member. Verbal dominance coding is based on traditional quantitative conversational dominance (number of talk turns). Gestural coding (conversational, ideational, object-adaptor, self-adaptor gestures) is based on classical gesture classifications. Beside a substantial effect of verbal dominance, the main result is that frequency of object-adaptors and conversational (only in large groups) and ideational (in both small and large groups) gestures increases perceived influence scores particularly when the verbal dominance of the speaker is low.     

Beyond Collaboration: Embodied Teacher Learning and the Discourse of Collaboration in Education Reform

In this paper I highlight the significance of Maurice Merleau-Ponty??s contribution to the study of teacher learning. I particularly draw on his notion of embodiment to show that professional knowledge is embodied knowledge and that teachers make sense of their professional world through their embodied action. I contrast my interpretation with a professional learning model that has been influential in Canada, the US, the UK, Australia and other countries. I suggest that policy makers interested in education reform initiatives would benefit from interrogating the nature of professional practices in education.     

Moral cognition and moral action: A theoretical perspective

Considerable theoretical work has been done in the area of moral reasoning. However, little conceptual thinking has been done about the relations between moral cognition and moral action. As a result, empirical research in this area has been unsystematic and difficult to interpret. A theoretical model, the Self Model, is proposed here, starting from the assumption that moral reasons are functionally related to action. First, a concept of cognitive motivation is presented as necessary for any cognitive account of morality. Two cognitive approaches to moral conduct, Piaget's and Haan's, are then discussed in their positive contributions and in their limitations. The Self Model is finally described through a set of empirically testable propositions. Its major theoretical characteristics are: it is cognitive, recognizing as the central function of human cognition the appraisal of truth; it acknowledges a basic duality of motivation, but stresses the normative pull of cognitive motivation; it is developmental; it uses the self as the central explanatory concept, establishing both the sense of personal responsibility and the dynamism of self-consistency.     

Recurrence analysis of sensorimotor trajectories in a minimalist perceptual task using sonification

Cognitive Processing - Active Perception perspectives claim that action is closely related to perception. An empirical approach that supports these theories is the minimalist, in which participants...