Compensatory Coordination of Release Parameters in a Throwing Task

The consistency and coordination of release parameters in ball-throwing movements were investigated. The authors used a newly developed index of coordination for release parameters (ICRP) that quantifies the degree of improvement of performance consistency caused by compensatory relationships among parameters (i.e., not caused by consistency of parameters). Eight participants practiced for 150 trials, with the nondominant hand, a ball-throwing task aimed at a stationary target. The magnitude of the ball-release velocity vector, among release parameters, as well as the performance was found to become consistent with practice. The ICRP score suggested that the release parameters were complementarily coordinated with one another, and that the coordination improved with practice. Those results indicate that compensatory relationships among varying release parameters contribute to reducing the variability of performance in a ball-throwing task whose goal is accuracy.     

Achievement Goal Impacts Students' Preferences for “Personalized Problems” in Computer-Adaptive Tests1

The contemporary development of psychometric theories and information technologies enables students to work on algorithm-based personalized tests in classroom settings. This study aims to investigate the relationship between students' achievement goals and what they prefer as “personalized problems” in computer-adaptive tests. We theoretically contrast achievement goals with developing competency through mastery and demonstrating competency through performance goals. We asked elementary and secondary school students to work on a computer-adaptive test and to complete questionnaires about what they prefer as “personalized problems” in computer-adaptive tests. The results revealed that while mastery goals positively predicted preference for challenging problems, performance goals positively predicted preference for problems that guaranteed students’ success. Moreover, only the preference for challenging problems positively predicted the intention to take computer-adaptive tests in the future. These results suggest that simply introducing a computer-adaptive test into the classroom may not be effective. We discuss how educational technologies should be integrated into human teaching activities.     

New stable icosahedral phases in Al-Pd-Ru and Al-Pd-Os systems

We have found stable icosahedral (i) phases in alloys with nominal compositions around Al 72 Pd 17 Ru 11 and Al 72 Pd 17 Os 11 . They display very sharp X-ray diffraction peaks, indicating high structural order as in other Al-based i-phases such as i-(Al-Pd-TM) (transition metal TM = Mn or Re) and i-(Al-Cu-TM) (TM =Fe, Ru or Os). The i phases are formed via peritectic reaction and, upon heating, they transform into a mixture of a liquid and the 1/0 cubic approximant phase. The electrical resistivity of the i phases was measured in a wide temperature range from 14K to above their melting points and a reversible change of the resistivity across the melting point has been observed in situ for the first time.     

Effects of chewing on cognitive processing speed

In recent years, chewing has been discussed as producing effects of maintaining and sustaining cognitive performance. We have reported that chewing may improve or recover the process of working memory; however, the mechanisms underlying these phenomena are still to be elucidated. We investigated the effect of chewing on aspects of attention and cognitive processing speed, testing the hypothesis that this effect induces higher cognitive performance. Seventeen healthy adults (20–34 years old) were studied during attention task with blood oxygenation level-dependent functional (fMRI) at 3.0 T MRI. The attentional network test (ANT) within a single task fMRI containing two cue conditions (no cue and center cue) and two target conditions (congruent and incongruent) was conducted to examine the efficiency of alerting and executive control. Participants were instructed to press a button with the right or left thumb according to the direction of a centrally presented arrow. Each participant underwent two back-to-back ANT sessions with or without chewing gum, odorless and tasteless to remove any effect other than chewing. Behavioral results showed that mean reaction time was significantly decreased during chewing condition, regardless of speed-accuracy trade-off, although there were no significant changes in behavioral effects (both alerting and conflict effects). On the other hand, fMRI analysis revealed higher activations in the anterior cingulate cortex and left frontal gyrus for the executive network and motor-related regions for both attentional networks during chewing condition. These results suggested that chewing induced an increase in the arousal level and alertness in addition to an effect on motor control and, as a consequence, these effects could lead to improvements in cognitive performance.     

A RUNS‐TEST ALGORITHM: CONTINGENT REINFORCEMENT AND RESPONSE RUN STRUCTURES

Four rats' choices between two levers were differentially reinforced using a runs‐test algorithm. On each trial, a runs‐test score was calculated based on the last 20 choices. In Experiment 1, the onset of stimulus lights cued when the runs score was smaller than criterion. Following cuing, the correct choice was occasionally reinforced with food, and the incorrect choice resulted in a blackout. Results indicated that this contingency reduced sequential dependencies among successive choice responses. With one exception, subjects' choice rule was well described as biased coin flipping. In Experiment 2, cuing was removed and the reinforcement criterion was changed to a percentile score based on the last 20 reinforced responses. The results replicated those of Experiment 1 in successfully eliminating first‐order dependencies in all subjects. For 2 subjects, choice allocation was approximately consistent with nonbiased coin flipping. These results suggest that sequential dependencies may be a function of reinforcement contingency.     

Trait‐Related Concepts Activate Stereotypically Consistent Concepts on the Same Stereotype Dimension,But May not Spread to the Other Stereotype Dimension

Applying the stereotype‐content model, which categorizes stereotypes into two dimensions (warmth and competence), we investigated whether gender‐stereotype‐related concepts activate other concepts on the same dimension and concepts on the other dimension. To test this, we conducted two experiments, both based on the Deese–Roediger–McDermott paradigm. In Experiment 1, we conceptually replicated the results of previous research, which revealed that when trait‐related words are presented to participants, gender‐stereotype‐related concepts induce the later false recognition of stereotypically consistent non‐presented words. Then, in Experiment 2, we revealed that exposure to gender‐stereotype‐related concepts induces the false recognition of non‐presented words relevant to stereotypical concepts on the same dimension, but not those on the other dimension. We conclude by discussing the underlying process of ambivalent stereotype activations, referring to implicit processes and system justification.     

Cognitive Bias for the Distribution of Ball Landing Positions in Amateur Tennis Players (Cognitive Bias for the Motor Variance in Tennis)

This study aimed to investigate whether the isotropy bias (estimating one's own motor variance as an approximately circular distribution rather than a vertically elongated distribution) arises in tennis players for the estimation of the two-dimensional variance for forehand strokes in tennis (Experiment 1), as well as the process underlying the isotropy bias (Experiment 2). In Experiment 1, 31 tennis players were asked to estimate prospectively their distribution of ball landing positions. They were then instructed to hit 50 forehand strokes. We compared the eccentricity of the ellipse calculated from estimated and observed landing positions. Eccentricity was significantly smaller in the estimated ellipse than in the observed ellipse. We assumed that the isotropy bias for the estimated ellipse comes from the process of variance estimation. In Experiment 2, nine participants estimated the 95% confidence interval of 300 dots. Eccentricity was significantly smaller in their estimated ellipses than it was in the ellipses for the dots, though the magnitude of bias decreased for the estimation of dots. These results suggest that the isotropy bias in tennis ball landing position includes the bias of recognizing landing position and the bias of estimating the ellipse confidence interval from the recognized landing position.     

Typ-Ken (an Amalgam of Type and Token) Drives Infosphere

Floridi’s infosphere consisting of informational reality is estimated and delineated by introducing the new notion of Typ-Ken, an undifferentiated amalgam of type and token that can be expressed as either type or token dependent on contingent ontological commitment. First, we elaborate Floridi’s system, level of abstraction (LoA), model, and structure scheme, which is proposed to reconcile ontic with epistemic structural reality, and obtain the duality of type and token inherited in the relationship between LoA and model. While we focus on the ontological commitment that can negotiate and emphasize the discrepancy between type and token, we show that most research focusing on different hierarchical layers (type and token) has converged onto the flattened perspective of type and token to clarify the role of ontological commitment. We propose the idea of Typ-Ken to avoid this flattening. In addition, we elaborate Taddeo and Floridi’s criticism of approaches to the symbol grounding problem and show that their criticism based on the zero semantical commitment condition is specific to the agents affected by the flattening. We then take bird flocks as a metaphor for the living infosphere as if it had one mind. The knowledge recently yielded by image analysis indicates that it is difficult for previous flock models based on agents equipped with the flattening of local (token) and global (type) to show the special feature of a flock of the scale-free proportion (SFP). We show here that agents based on the Typ-Ken can reveal the SFP, which is the essential characteristic of the living infosphere. In other words, Typ-Ken is an expression for informational reality (LoA and model with ontological commitment) that can reveal seamless local and global interactions in the functioning of a flock or infosphere.