Absence of Ankle Stiffening While Standing in Focus and Cognitive Task Conditions in Older Adults

Abstract

Research suggests that an external focus or cognitive task may improve postural control. Removing attention from movement production may promote automaticity, or the tasks may promote ankle stiffening. To investigate these two theories, twenty older adults stood while performing baseline standing, internal focus, external focus, and two cognitive tasks. Changes in postural control occurred in external focus and cognitive task conditions compared to baseline and internal focus, while no change occurred in cocontraction indices. This suggests that an external focus and cognitive task can improve postural control in older adults. Since no change occurred in cocontraction indices across conditions, this suggests that stiffening cannot explain these changes. Instead, changes could be due to automaticity of sway.     

Aspects of spatial cognition in capuchins (Cebus apella): frames of reference and scale of space

Frames of reference (i.e. sets of loci defining spatial locations) determine animals’ performances in object search tasks. Reference frames are used at different scales. Although much behavioural research has been conducted on search strategies in many animal species, relatively little has been done on nonhuman primates. The two experiments reported here focused on the relative strength and the level of functioning of different reference frames at the small-scale level in four capuchins (Cebus apella). Two identical boxes and a landmark were placed on a round platform that could be rotated. A reward was hidden in subject’s view under one box, and then a sash-screen was lowered to hide the rotation of the platform; the sash-screen was then lifted and the subject allowed to search for the reward. In experiment 1 the rewarded box was always the closer to the landmark, in experiment 2 it could be either the box closer to or the box farther from the landmark. Capuchins were successful after invisible rotations in experiment 1, but they failed after invisible rotations in experiment 2. Two possible explanations are proposed: (1) capuchins relied heavily on the left-right body-axis as a frame, and they could only substitute it with a simple association between the rewarded position and the landmark; or (2) capuchins failed because they chose external cues in the room, therefore on a inappropriate scale. The latter explanation allows two further inferences: (a) the capuchins’ choice was indirectly related to their body-axes; and (b) the capuchins revealed a cognitive asymmetry between small-scale and large-scale spaces, thus differing from humans. Received: 10 October 1999 / Accepted after revision: 4 May 2000     

The distribution matters: two types of sample-size tasks

Different studies on how well people take sample size into account have found a wide range of solution rates. In a recent review, Sedlmeier and Gigerenzer (1997) suggested that a substantial part of the variation in results can be explained by the fact that experimenters have used two different types of sample-size tasks, one involving frequency distributions and the other sampling distributions. This suggestion rested on an analysis of studies that, with one exception, did not systematically manipulate type of distribution. In the research reported in this paper, well-known sample-size tasks were used to examine the hypothesis that frequency distribution versions of sample-size tasks yield higher solution rates than corresponding sampling distribution versions. In Study 1, a substantial difference between solution rates for the two types of task was found. Study 2 replicated this finding and ruled out an alternative explanation for it, namely, that the solution rate for sampling distribution tasks was lower because the information they contained was harder to extract than that in frequency distribution tasks. Finally, in Study 3 an attempt was made to reduce the gap between the solution rates for the two types of tasks by giving participants as many hints as possible for solving a sampling distribution task. Even with hints, the gap in performance remained. A new computational model of statistical reasoning specifies cognitive processes that might explain why people are better at solving frequency than sampling distribution tasks. Copyright© 1998 John Wiley & Sons, Ltd.     

Indirect treatment of children via parent training: A burgeoning form of secondary prevention

This study reviews research on the process and outcome of parent training (PT) conducted over the past 20 years. A distinction is made between parent behavioral training and other forms of PT. It is concluded that all forms of PT research have become more molecular in the questions addressed and otherwise more scientifically rigorous. Compared to other forms of psychotherapeutic intervention, PT produces more consistently positive outcome changes and is clearly more economical of professional time and thus of consumer cost. As such, although less than 3% of all previous PT studies have dealt with prevention, PT is recommended as a potential form of secondary prevention worth consideration by applied and preventive psychologists.     

Components of attentional effort for repeated tasks

This paper identifies four attentional processes that increase efficiency and accuracy in repeated lexicographic tasks using an instructed strategy approach. We propose a framework to decompose attentional effort used to make a decision into four components: Orientation, Wrong Target, Duration, and Repetition. Orientation assesses attention to decision rules and the location of relevant information. Wrong Target measures wasted effort on unneeded information. Duration gauges time spent on each piece of needed information. Repetition measures the number of views on each relevant item. Greater Orientation is associated with lower effort in other components and increased accuracy. Repetition is most variable across individuals but generates the greatest improvement with practice. Duration is less affected by the other components and shows minimal improvement with experience. Finally, Wrong Target is similarly resistant to practice, but it is the only component strongly and positively associated with making errors.     

Adults' Acquisition of Novel Dimension Words: Creating a Semantic Congruity Effect

The semantic congruity effect is exhibited when adults are asked to compare pairs of items from a series, and their response is faster when the direction of the comparison coincides with the location of the stimuli in the series. For example, people are faster at picking the bigger of 2 big items than the littler of 2 big items. In the 4 experiments presented, adults were taught new dimensional adjectives (mal/ler and borg/er). Characteristics of the learning situation, such as the nature of the stimulus series and the relative frequency of labeling, were varied. Results revealed that the participants who learned the relative meaning of the artificial dimensional adjectives also formed categories and developed a semantic congruity effect regardless of the characteristics of training. These findings have important implications for our understanding of adult acquisition of novel relational words, the relationship between learning such words and categorization, and the explanations of the semantic congruity effect.     

The roles of hopeful thinking in preventing problems and enhancing strengths

From its most famous tale, that of Pandora, hope was meant to prevent the emergence and reemergence of life difficulties. A new model defining hope as a combination of agentic pathways and goal-directed thinking is reviewed. Comparisons of the similarities of this theory to other existing theories are made. The beneficial roles of hope in primary (before the appearance of a problem) and secondary (after a problem has appeared) prevention are explored. Primary enhancement is introduced as involving those thoughts and actions that establish optimal functioning and satisfaction. Secondary enhancement is posited to describe those thoughts and actions that are undertaken over time so as to further functioning and satisfaction in order to reach peak levels. Using hope theory as a lens, these primary and secondary enhancement processes are described. The natural synergy between prevention and enhancement activities is discussed, along with the future priorities for using hope in prevention and enhancement efforts.     

Distraction while driving: The case of older drivers

As the impairment of older drivers is especially found in perception and attention, one could assume that they are especially prone to distraction effects of secondary tasks performed while driving. The aim of the study was to examine the effect of age on driving performance as well as the compensation strategies of older drivers under distraction. 10 middle-aged and 10 older drivers drove in a simulator with and without a secondary task. To assess driving performance the Lane Change Task (Mattes, 2003) was used. This method aims at estimating driver demand while a secondary task is being performed, by measuring performance degradation on a primary driving-like task in a standardized manner. The secondary task – a self-developed computer-based version of “d2 Test of Attention” was presented both with and without time pressure. The results show that older participants’ overall driving performance (mean deviation from an ideal path) was worse in all conditions as compared to the younger ones. With regard to lane change reaction time both age groups were influenced by distraction in a comparable manner. However, when the lane keeping performance (standard deviation of the lateral position) was examined, the older participants were more affected than the younger ones. This pattern could be explained by compensation strategies of the older drivers. They focused on the most relevant part of the driving task, the lane change manoeuvres and were able to maintain their performance level in a similar way as did younger drivers. The driving performance of the older participants was not additionally impaired when the secondary task imposed time pressure. Overall, subjective rating of driving performance, perceived workload and perceived distraction was found to be similar for both age groups. The observed trends and patterns associated with distraction while driving should contribute to the further research or practical work regarding in-vehicle technologies and older drivers.     

Young adults talk about their problems

This study aims to explore how young adults in psychotherapy and young adults in general describe their problems and how their problem formulations change over time. Two matched samples from longitudinal prospective studies were compared using thematic analysis. Semi-structured, in-depth interviews were conducted at baseline, 1.5 years after termination of psychotherapy (N=12) in the clinical sample and 3 years after baseline in the non clinical sample (N=12). Inductive thematic analysis revealed six themes: problems associated with oneself, family, intimate relationships, sense of belonging, occupation, and social roles. The psychotherapy sample was characterized by problems with oneself closely related to other problematic areas, at both pre-treatment and at follow-up 1.5 years after termination, while problematic sense of belonging was a general theme only prior to psychotherapy. However, they were less troubled by their problems after psychotherapy. Problems with oneself decreased considerably in the non-clinical sample, while problems with intimate relationships were twice as frequent at follow-up. In the psychotherapy sample, the initial experience of being passively trapped within their problems was transformed into an experience of being an active agent in their own life. However, considerable differences between the psychotherapy sample and non-clinical sample still persisted at follow-up.     

Vicarious traumatization and secondary traumatic stress: A research synthesis∗

Vicarious traumatization (VT) refers to harmful changes that occur in professionals’ views of themselves, others, and the world, as a result of exposure to the graphic and/or traumatic material of their clients. Secondary traumatic stress (STS) refers to a set of psychological symptoms that mimic post-traumatic stress disorder, but is acquired through exposure to persons suffering the effects of trauma. Numerous studies have sought to identify correlates of both VT and STS, yet there still exists a lack of conceptual clarity in the literature about VT, STS, and the related constructs of burnout and compassion fatigue. This has made it difficult to use the literature to inform practice and training. This study clarifies the definitions of VT and STS and uses levels of evidence analysis to synthesize the research findings to date. Originally planned as a meta-analysis, the study was re-designed as methodological issues in the literature became apparent that would call into question the validity of a meta-analysis. The current method of analysis documents the degree of evidence for the most commonly researched factors that have been researched as possible contributors to the development of both VT and STS, synthesizing the findings of published research and dissertations written in the English language from 1994–2003. Findings indicate that persuasive evidence exists for personal trauma history, reasonable evidence for perceived coping style, and some evidence for supervision experiences, as important predictors of VT. Persuasive evidence for amount of exposure to trauma material and reasonable evidence for personal trauma history are indicated as important in the development of STS. Limitations of the current study and directions for further research are discussed.