Growing older does not always mean moving slower: examining aging and the saccadic motor system

Although humans typically move more slowly as they age, one exception may be the saccadic motor system. To fully determine whether the execution of saccades is affected by age, the authors examined detailed kinematics of vertical and horizontal saccades across a range of saccadic amplitudes (4 degrees, 8 degrees, and 12 degrees). Ten younger and 20 older adults participated in each experiment. Whereas in the 1st experiment, the authors assessed volitionally generated saccades, in the 2nd experiment, they evaluated reflexively generated saccades. The results of those experiments showed that the saccadic motor system is relatively impervious to the effects of aging; in fact, the differences between vertical and horizontal saccades were more evident than were differences between saccades produced by younger and older adults. The authors discuss possible reasons for that relative resistance to aging.     

Trait and social processes in the link between social support and affect: an experimental, laboratory investigation

This study investigated the extent to which the link between perceived social support and affect reflected support recipients' trait perceived support as well as three distinct social processes: the objective supportiveness of providers, the unique relationships among recipients and providers that were stable over occasions, as well as the unique relationships that varied across occasions. Ten recipients interacted with each of the same four providers on five separate occasions, for a total of 200 interactions. Recipients and independent observers rated recipient affect and provider support. Greater perceived support was related to greater positive affect for recipients' trait perceived support, as well as for relationships that were stable over occasions and relationships that varied across occasions. No social support effects were found for negative affect. Perceived similarity was a consistent predictor of recipients' support perceptions. Implications for social support models and interventions were discussed.     

Oversimplifying evolutionary psychology leads to explanatory gaps

Comments on Evolutionary psychology: Controversies, questions, prospects, and limitations (see record 2010-02208-001) by Confer et al. They argued that SST cannot explain the existence of either homosexuality or suicide within the human species. We contend that a sufficiently nuanced evolutionary position has no difficulties explaining either phenomenon. Also in this account, it is assumed that all psychological functioning must serve survival and reproduction. However, since evolution selects against certain qualities (it does not select for qualities, as it is commonly, but incorrectly, described), two types of qualities should remain intact for any species: (a) those that facilitate survival and reproduction and (b) those that do not impede survival and reproduction at the population level.     

Sign determination of the 57 Fe electric-field gradient in Al-based crystals and icosahedral quasicrystals

Abstract

The icosahedral quasicrystals i-AIMn, isomorphically substituted by 28 at.% Fe or by a mixture of (CrFe) atoms, have been studied for the first time by in-field Mössbauer spectroscopy in order to determine the sign and asymmetry parameter of the dominant electric-field gradient (EFG) term. In addition, the orthorhombic o-Al(MnFe) and cubic α- and hexagonal β-Al(MnFe)Si crystalline phases have been studied. We show that the previous Mössbauer results are inadequate for determining whether there are two sites in the quasicrystalline structure in the ratio of the golden number. Our results for i-Al(MnFe) show that the dominant EFG is negative, with an asymmetry parameter of about 0·6. For i-Al(CrFe), essentially no deviations are found from the model of Czjzek or the Gaussian isotropic model. One crystalline phase, the hexagonal β phase, is found to have a very similar quadrupole effect to that found in i-Al(MnFe). In addition it is found that this phase undergoes a change which is at least partly of magnetic origin.     

Creative Writing as a Medical Instrument

Listening and responding to patients’ stories for over 20 years as an emergency physician has strengthened my appreciation for the many ways that the skills and principles drawn from writing fiction double as necessary clinical skills. The best medicine doesn’t work on the wrong story, and the stories patients tell sometimes feel like first drafts—vital and fragile works-in-progress. Increasingly complex health challenges compounded by social, financial, and psychological burdens make for stories that are difficult to articulate and comprehend. In this essay, I argue that healthcare providers need to think like creative writers and the skills and sensitivities necessary to story construction deserve a vital space in medical education. A thorough understanding of story anatomy and the imaginative flexibility to work stories into open spaces serve as antidotes to the reductive nature of clinical decision making and have implications as patient safety and risk management strategies. The examples that I have selected demonstrate how thinking like a creative writer functions at the bedside, providing tools for clinical excellence and empathy. This approach asks that we re-imagine the importance of story in clinical care: from a vehicle to a diagnosis to its place as a critical destination.     

Rapid Aimed Limb Movements: Differential Effects of Practice on Component Submovements

Three experiments are reported in which subjects practiced rapid aimed limb movements (arm pointing and wrist rotation) toward a visible target region. Subjects were required to minimize their movement durations while still landing in the target. The movement trajectories were examined to assess the effects of practice on separate component submovements of the limb movements. The results revealed that practice improved primarily temporal, not spatial, aspects of performance. Practice reduced the overall movement durations, but had different effects on the individual submovements: Practice allowed subjects to reduce the amount of time spent performing final corrective submovements, but actually increased slightly the time needed to produce the initial ballistic submovement. The results suggest that practice in the present task primarily enhanced the ability to use feedback information, but there was also some evidence of changes in the ballistic, preprogrammed portion of the movements. The results demonstrate that analysis of submovements can reveal important details of the underlying motor control processes.     

Repeated measurement of salivary cortisol within and across days among shy young adults

Temperamental shyness emerges early in childhood and remains relatively stable throughout development and has been associated with high and low levels of the stress hormone cortisol. Studies examining the relation between shyness and cortisol have been limited because they have traditionally collected only one measure of cortisol on a single day in the laboratory, restricting the reliability and diurnal profile of the measure in the participant’s everyday environment. We collected 15 saliva samples across three separate days (i.e., upon waking, +60 min post-waking, +8 h post-waking, +10 h post-waking, and bedtime) in a sample of healthy young adults selected for high and low shyness in order to characterize a portion of the diurnal cortisol rhythm. Overall, shy individuals demonstrated relatively lower cortisol across the day and across multiple mornings than non-shy adults. Higher self-reported social anxiety across multiple measures was also related to lower total cortisol levels across all participants. The present study replicates and extends our previous findings of low salivary cortisol measured in the laboratory in shy adults to repeated measurement in their everyday environments.