Correction of a Technical Error in the Golf Swing: Error Amplification Versus Direct Instruction

Performance errors drive motor learning for many tasks. The authors' aim was to determine which of two strategies, method of amplification of error (MAE) or direct instruction (DI), would be more beneficial for error correction during a full golfing swing with a driver. Thirty-four golfers were randomly assigned to one of three training conditions (MAE, DI, and control). Participants were tested in a practice session in which each golfer performed 7 pretraining trials, 6 training-intervention trials, and 7 posttraining trials; and a retention test after 1 week. An optoeletronic motion capture system was used to measure the kinematic parameters of each golfer's performance. Results showed that MAE is an effective strategy for correcting the technical errors leading to a rapid improvement in performance. These findings could have practical implications for sport psychology and physical education because, while practice is obviously necessary for improving learning, the efficacy of the learning process is essential in enhancing learners' motivation and sport enjoyment.     

Ethical recommendations for workers on aggression and predation in animals

The recommendations of a recent workshop (Leiden, Netherlands, November 17–18, 1990) concerning the use of animals in research on aggression and predation are listed. Major considerations included the grade of organisation/level of development of the organism, the duration and intensity of the interaction, post-treatment factors, the number of animals and reuse of animals. It is hoped that the recommendations will help scientists working in these areas to consider the increasingly important ethical dimension.     

Stimulus-dominance effects and lateral asymmetries for language in normal subjects and in patients with a single functional hemisphere

The assessment of language laterality by the dichotic fused-words test may be impaired by interference effects revealed by the dominant report of one member of the stimuli-pair. Stimulus-dominance and ear asymmetry were evaluated in normal population (48 subjects of both sex and handedness) and in 2 patients with a single functional hemisphere. Results show that in normals the number of stimulus-dominated responses is five times higher than in patients, and is negatively correlated to the index of laterality. It is suggested that dichotic stimuli may interfere one with another during the subcortical acoustic processing and at cortical level, when competing for verbal output. Subcortical interference accounts for stimulus-dominance in the single-hemisphere patients. In normal subjects, the dichotic discrimination is disturbed mainly during the hemispheric cross-talk needed for the oral-verbal processing of dichotic inputs. The frequency of 'interhemispheric' interference, as well as the extents of ear asymmetry, may both depend on differences in the processing stage of the competing inputs, and then they may be influenced by differential verbal skills of LH and RH. Very unequal levels of verbal analysis of the dichotic stimuli may hinder reciprocal interference during the hemispheric cross-talk thus yielding large ear asymmetries associated to small dominance effects.     

Development Projects and Life Satisfaction: An Impact Study on Fair Trade Handicraft Producers

Is there a correspondence between subjective and objective wellbeing indicators in development programs? We investigate this question by evaluating the impact of Fair Trade affiliation on the subjective wellbeing of a sample of Peruvian (treatment and control) producers from two different Fair Trade projects in two socioeconomic environments, one relatively poorer (Juliaca) and the other relatively more affluent (Chulucanas). We find a direct and an indirect effect. The direct effect acts positively via affiliation years in the poorer project and via trade diversification in both projects. The indirect effect acts through the reduction of poverty and relative income. Consistently with the concave income-happiness assumption, the variables generating the indirect effect have a much weaker impact for producers living in the relatively better-off socioeconomic environment, net of the lower FT economic impact in this area.     

Plant neurobiology: from sensory biology, via plant communication, to social plant behavior

In plants, numerous parameters of both biotic and abiotic environments are continuously monitored. Specialized cells are evolutionary-optimized for effective translation of sensory input into developmental and motoric output. Importantly, diverse physical forces, influences, and insults induce immediate electric responses in plants. Recent advances in plant cell biology, molecular biology, and sensory ecology will be discussed in the framework of recently initiated new discipline of plant sciences, namely plant neurobiology.     

Male–male combats in a polymorphic lizard: residency and size,but not color,affect fighting rules and contest outcome

Theoretical models predict that the outcome of dyadic agonistic encounters between males is influenced by resource‐holding potential, resource value, and intrinsic aggressiveness of contestants. Moreover, in territorial disputes residents enjoy a further obvious competitive advantage from the residency itself, owing to the intimate familiarity with their territory. Costs of physical combats are, however, dramatically high in many instances. Thus, signals reliably reflecting fighting ability of the opponents could easily evolve in order to reduce these costs. For example, variation in color morph in polymorphic species has been associated with dominance in several case studies. In this study, we staged asymmetric resident‐intruder encounters in males of the common wall lizard Podarcis muralis, a species showing three discrete morphs (white, yellow, and red) to investigate the effects of asymmetries in color morph, residency, and size between contestants on the outcome of territorial contests. We collected aggression data by presenting each resident male with three intruders of different color morph, in three consecutive tests conducted in different days, and videotaping their interactions. The results showed that simple rules such as residency and body size differences could determine the outcome of agonistic interactions: residents were more aggressive than intruders, and larger males were competitively superior to smaller males. However, we did not find any effect of color on male aggression or fighting success, suggesting that color polymorphism in this species is not a signal of status or fighting ability in intermale conflicts. Aggr. Behav. 35:274–283, 2009. © 2009 Wiley‐Liss, Inc.     

Preference for the sites of fighting in two teleost species

Males of two species of freshwater fish (convict cichlids and Italian freshwater gobies) fought with conspecifics and subsequently remained near the visual and spatial cues that had been paired with those social encounters. These data show that postfight preference for combat sites is a phenomenon of some generality among teleosts. The likely role of learning in establishing postfight preferences for the locales of aggression is discussed.     

Direct gaze modulates face recognition in young infants

From birth, infants prefer to look at faces that engage them in direct eye contact. In adults, direct gaze is known to modulate the processing of faces, including the recognition of individuals. In the present study, we investigate whether direction of gaze has any effect on face recognition in four-month-old infants. Four-month infants were shown faces with both direct and averted gaze, and subsequently given a preference test involving the same face and a novel one. A novelty preference during test was only found following initial exposure to a face with direct gaze. Further, face recognition was also generally enhanced for faces with both direct and with averted gaze when the infants started the task with the direct gaze condition. Together, these results indicate that the direction of the gaze modulates face recognition in early infancy.     

A Duality for Involutive Bisemilattices

Studia Logica - We establish a duality between the category of involutive bisemilattices and the category of semilattice inverse systems of Stone spaces, using Stone duality from one side and the...