Assessing muscular fatigue with a portable tremor measurement system suitable for field use

The utility of a portable tremor measurement system for detecting muscle fatigue was evaluated. Static arm extension was used to induce fatigue. A probe containing two accelerometers, held in the extended hand, recorded horizontal and vertical tremor oscillations in the 1- to 18-Hz range. Several summary amplitude and frequency measures were then derived to analyze hand/arm tremor in the unfatigued and the fatigued states. Large increases from unfatigued to fatigued states were observed in all of the amplitude measures in both axes. Summary frequency measures were far less sensitive to fatigue. Correlations between consecutively measured observations revealed high levels of reliability (r τ .80) in all of the amplitude measures, but not in the frequency measures. The most robust index of fatigue was the total power in the entire 1- to 18-Hz spectrum. The other amplitude measures, however, are suitable for examining the effects of fatigue in isolated portions of the spectrum.     

Processing of text containing artificial inclusion relations

The present studies were based on the hypothesis that the majority of college students have available to them the appropriate schema for understanding set inclusion relations, but that various factors influence the likelihood that the schema is used in the processing of text containing artificial inclusion relations. Although group data did not support this hypothesis, the data of individual subjects could be readily interpreted as resulting from the selection of one of a small set of representational schemata. Among the factors shown to influence schema selection were the choice of sentence frame used to present each relation, the presence or absence of real-world contextual information, and the structure (simple vs. complex) of the underlying inclusion relation. In addition, one experiment showed that the processes used in constructing a mental representation of an inclusion relation and in retrieving information from the representation are similar to those used with linear orderings.     

Habit reversal in the turtle

Two groups of mature “painted” turtles were trained in a T-maze. One group had five trials per day, with correct and incorrect turns reversed for each animal whenever it reached the criterion of five errorless trials on a given day. The second group had 10 trials per day, with correct and incorrect turns reversed daily, irrespective of the performance of the animals. Only in the data for the second group did there appear some indication of progressive improvement in habit reversal. The results are considered in relation to those obtained in analogous experiments with other species.     

Recommendations and resources for counseling older workers

The purpose of this article is to provide employment counselors an overview of the growth in the number of older workers in the U.S. Various demographic, employment, and career development trends are presented. Specific suggestions for counseling older workers are offered. Readers are directed to a number of high‐quality online resources for older workers.     

Arrest and intimate partner violence: Toward a more complete application of deterrence theory

Two decades of research have failed to produce consistent and compelling results that arrest deters intimate partner violence. This tradition of research is reviewed, concluding that little can be learned about the deterrent efficacy of arrest (or other sanctions) for this type of violence until a more complete framework of deterrence theory is specified to guide further research. The framework should delineate mediating influences besides deterrence, linking arrest to the prevention, reduction, or cessation of intimate partner violence, and factors that moderate those influences. Such factors bear on the differential sensitivity to sanctions on the part of actual or potential perpetrators of intimate partner violence. Recommendations for future research are offered, including suggestions for data needed to draw defensible causal inferences about these mediating and moderating influences.     

Contemporary ethics from an ambiguous past.

Kaveny recommends models drawn from the Gospel of John and the practices of the early church for modern Christians in their response to older women and their health needs. She draws upon a historical reconstruction of the early Christian Order of Widows to propose a normative standard of care for elderly women, one that attends seriously to their bodily needs but also to their needs for inclusion and engagement in the social and vocational world both as givers and recipients of care. This is also to serve as an overarching model for a bioethics that prizes the embodied existence of all women and rejects judgments of appropriate treatment based on their social utility. The following response raises questions about the exegetical and historical foundations of Kaveny's analysis. However, these caveats may not detract substantially from the normative usefulness of her work.     

Age-related differences in the involvement of the prefrontal cortex in attentional control

We investigated the relative involvement of cortical regions supporting attentional control in older and younger adults during performance on a modified version of the Stroop task. Participants were exposed to two different types of incongruent trials. One of these, an incongruent-ineligible condition, produces conflict at the non-response level, while the second, an incongruent-eligible condition, produces conflict at both non-response and response levels of information processing. Greater attentional control is needed to perform the incongruent-eligible condition compared to other conditions. We examined the cortical recruitment associated with this task in an event-related functional magnetic resonance imaging paradigm in 25 older and 25 younger adults. Our results indicated that while younger adults demonstrated an increase in the activation of cortical regions responsible for maintaining attentional control in response to increased levels of conflict, such sensitivity and flexibility of the cortical regions to increased attentional control demands was absent in older adults. These results suggest a limitation in older adults’ capabilities for flexibly recruiting the attentional network in response to increasing attentional demands.