Asymmetry of force fluctuation during low and moderate intensity isometric knee extensions

The purpose of this study was to investigate the asymmetry of force fluctuation during isometric knee extension at low and moderate intensities. 11 healthy men (M age = 21 yr., SD = 1) performed unilateral force matching tasks; sustained isometric knee extension at 20% and 30% maximal voluntary contraction (MVC). During the tasks, a mechanomyogram was measured by an accelerometer arrangement placed on the vastus lateralis. Although force fluctuation was not significantly different between the two legs at 20% MVC, it was higher in the left (weaker) leg than in the right (stronger) leg at 30% MVC. A significant difference in mean power frequency of the mechanomyographic signal between the two legs was also observed only at 30% MVC. These results suggest that the asymmetry of force fluctuation during isometric knee extension was not statistically significant at low intensity; however, it was significant at moderate intensity. These differences in force fluctuation between intensities might be influenced by different motor-unit firing rates in active muscle.     

Emotional fortification: Indulgent consumption and emotion reappraisal and their implications for well‐being

This paper suggests that indulgent consumption could be used as an emotion regulation strategy and that it could have positive implications for well‐being. “Emotional fortification,” where the use of one emotion regulation strategy is correlated with the use of another strategy, is confirmed in this study. People who frequently use emotion reappraisal are more likely to use indulgence than people who use this reappraisal strategy infrequently. Study 1 shows the correlation between indulgence and reappraisal. Study 2 examines the implications of indulgence and reappraisal for life satisfaction and personal well‐being. These findings suggest that indulgence is not always harmful for people and society.     

Ear advantage and consonance of dichotic pitch intervals in absolute-pitch possessors

Left-right asymmetry in the central processing of musical consonance was investigated by dichotic listening tasks. Two piano tones paired at various pitch intervals (1-11 semitones) were presented one note in each ear to twenty absolute-pitch possessors. As a result, a weak overall trend for left ear advantage (LEA) was found, as is characteristic of trained musicians. Second, pitches of dissonant intervals were more difficult to identify than those of consonant intervals. Finally, the LEA was greater with dissonant intervals than with consonant intervals. As the tones were dichotically presented, the results indicated that the central auditory system could distinguish between consonant and dissonant intervals without initial processing of pitch-pitch relations in the cochlea.     

Semantic category discrimination and N400

14 subjects performed a semantic category-discrimination task in which they were presented pairs of words and asked to judge whether these belonged to the same category. Three semantic distance conditions, established for the word pairs on the basis of a survey, were semantically close condition (mammals and birds condition) and two semantically distant conditions (mammals and tools condition and birds and tools condition). The reaction times and the percentage of errors were significantly greatest for the mammals and bird condition. There were no significant differences among the three different conditions in N400 latency for target, but the amplitude of N400 tended to be largest for the mammal and bird condition. Comparison N400 of prime and target for each of the conditions showed that the latency for prime was longer than for target in all three conditions.     

Beyond drug effects and dependent variables: the use of the Poisson-Erlang model to assess the effects of D-amphetamine on information processing

Several studies have shown that d-amphetamine (DAMP) speeds mean reaction time (RT). However, the use of mean RT may obscure important aspects of the drug response. Therefore we applied the Poisson-Erlang (PE) stochastic model of choice reaction time proposed by Pieters (1985) to the RT distribution. This model proposes that the RT distribution is generated by two states: Processing (P) and Distraction (D). RT represents the sum of the time spent in each of these states. P is the time taken to complete a set of cognitive operations which are required to give a correct response. D represents the time taken by all other activities. RTs were collected using a task (SERS) in which stimulus and response complexity each had two levels, easy and hard. Subjects were tested pre- and postdrug. Drug conditions were: placebo, 10 mg d-amphetamine (DAMP), 4 mg of the dopamine agonist, pimozide, and a combination of DAMP and pimozide (COMBO). Parameters of the model were derived using methods described by Pieters. Four measures were analyzed: Processing Time (PT); Mean Time per distraction (XTD); Distraction Rate (DR); and Total Distraction Time per trial (TDT). Mean RT is also presented. Analyses of the effects of task conditions on the parameters of the model were made using the predrug sessions. Mean RT was increased by both stimulus and response complexities as was PT. TDT was increased by the task conditions. The PE measures did not change over days. DAMP speeded mean RT. However, this effect did not interact with the task factors. DAMP speeded processing and reduced distraction. Processing was speeded only in the hard response condition, distraction time was reduced only in the easy response condition. The results indicate that the PE model can be successfully applied to fast RT tasks. More importantly, the parameters of the model revealed important pharmacological effects that were not apparent in mean RT. DAMP speeds cognitive operations related to motor preparation and reduces the effects of distraction. Consistent with past studies there are no indications that DAMP interacted with stimulus processing. The distraction effect appears to be mediated by an increase in the rate of distraction and a decrease in the average time of these distractions.     

Do Emotions after Receiving Test Results Predict Review Activities? An Intra‐Individual Analysis

In the present study, we examined intra‐individual relations among emotions when receiving test results and subsequent test review activities, and the direct and moderating effects of perceptions of test value. The participants, 90 first‐year students at a private girls' secondary school, self‐reported their present emotional state immediately after receiving their test results and their test review activities 1 week after the tests were returned. The same survey was conducted on four occasions. Results of multilevel analyses indicated that emotions experienced when receiving test results did not predict subsequent learning behavior. The results also showed that relations among emotions and review activities differed across students. Although we investigated whether such individual differences in relations might be attributed to perceptions of test value, no moderating effect could be observed. Furthermore, improvement‐oriented test mindsets were found to be positive predictors of review activities by investigating the direct effect of perceptions of test value. These findings suggest that modifying students' perceptions of test value may promote appropriate learning behavior.     

A general approach to causal mediation analysis

Traditionally in the social sciences, causal mediation analysis has been formulated, understood, and implemented within the framework of linear structural equation models. We argue and demonstrate that this is problematic for 3 reasons: the lack of a general definition of causal mediation effects independent of a particular statistical model, the inability to specify the key identification assumption, and the difficulty of extending the framework to nonlinear models. In this article, we propose an alternative approach that overcomes these limitations. Our approach is general because it offers the definition, identification, estimation, and sensitivity analysis of causal mediation effects without reference to any specific statistical model. Further, our approach explicitly links these 4 elements closely together within a single framework. As a result, the proposed framework can accommodate linear and nonlinear relationships, parametric and nonparametric models, continuous and discrete mediators, and various types of outcome variables. The general definition and identification result also allow us to develop sensitivity analysis in the context of commonly used models, which enables applied researchers to formally assess the robustness of their empirical conclusions to violations of the key assumption. We illustrate our approach by applying it to the Job Search Intervention Study. We also offer easy-to-use software that implements all our proposed methods.     

“Not by bread alone…” How does Jesus free and unite us?

Then Jesus was led up by the Spirit into the wilderness to be tempted by the devil. And he fasted forty days and forty nights, and afterwards he was hungry. And the tempter came and said to him: “If you are the Son of God, command these stones to become loaves of bread.” But he answered: “It is written: ‘Man shall not live by bread alone, but by every word that proceeds from the mouth of God’.” Matt. 4: 1–4.     

Self‐expression and relationship formation in high relational mobility environments: A study of dual users of American and Japanese social networking sites

This study proposes that self‐expression motivation, an aspect of independent/individualistic psychological tendencies, aids in the formation of social relationships when social relationships are open and mobile. In societies characterised by high relational mobility (e.g., North America), which creates market‐like competition in social relationships, individuals must express their uniqueness and worthiness to form new social relationships. Self‐expression motivation has a relatively weak effect on relationship formation in low relational mobility societies (e.g., Japan), where social relationships are generally predetermined. This hypothesis was examined and supported through a study on dual users of two social networking sites—Facebook and Mixi (the “Facebook of Japan”). As expected, relational mobility was higher on Facebook than on Mixi. Moreover, the association between self‐expression motivation and the number of new friends met on Facebook/Mixi was more positive for Facebook than it was for Mixi. The social functionality of independent tendencies is then discussed.     

Culture and group-based emotions: could group-based emotions be dialectical?

Group-based emotions are experienced when individuals are engaged in emotion-provoking events that implicate the in-group. This research examines the complexity of group-based emotions, specifically a concurrence of positive and negative emotions, focusing on the role of dialecticism, or a set of folk beliefs prevalent in Asian cultures that views nature and objects as constantly changing, inherently contradictory, and fundamentally interconnected. Study 1 found that dialecticism is positively associated with the complexity of Chinese participants’ group-based emotions after reading a scenario depicting a positive intergroup experience. Study 2 found that Chinese participants experienced more complex group-based emotions compared with Dutch participants in an intergroup situation and that this cultural difference was mediated by dialecticism. Study 3 manipulated dialecticism and confirmed its causal effect on complex group-based emotions. These studies also suggested the role of a balanced appraisal of an intergroup situation as a mediating factor.