Parameters of digitally averaged potentials of individual motor units]

Of sixty normal subjects of different age six different muscles each were examined electromyographically. The activity pattern was recorded for moderate voluntary innervation and superposed digitally. The parameters of digitally averaged summation action potentials were compared with those of manually assessed potentials. The two methods gave identical results: The duration of potentials was between 5 and 10 ms. It increased in the younger and older age groups and showed only slight changes in middle-aged persons. Only minor differences were found between the muscles of one age group, an exception being the orbicularis oris muscle. The results obtained are compared with values reported in the literature.     

The tonic immobility reaction in chickens: Response characteristics and methodology

A total of 379 chickens were run in five studies to assess the effect of different procedures on tonic immobility and to measure some of the response components of the reaction. The optimal period of manual restraint, by way of producing the most durable immobility response, was found to be 15 sec, and pretest holding conditions were shown to exert a significant influence on the reaction in naive birds. Birds who defecated during immobility or shortly after termination, remained immobile longer than comparable nondefecators. Duration of eye closure and latency of vocalization were also found to be good predictors of the duration of an immobility episode.     

Positive Feelings at School: On the Relationships Between Students’ Character Strengths,School-Related Affect,and School Functioning

The present study was designed to examine the relationships between students’ character strengths, school-related affect, positive school functioning (i.e., motivation to learn, interest, and engagement at class), and school achievement following the “engine model of well-being” that is focusing on inputs (e.g., personality traits), processes (e.g., moods, emotions), and outcomes (e.g., engagement, accomplishments) within the context of well-being research. A sample of 196 children completed the Values in Action Inventory of Strengths for Youth, which assesses 24 character strengths, and the PANAS-C that assesses school-related positive and negative affect. Additionally, homeroom teachers rated students’ positive school functioning (i.e., motivation, engagement, and interest at school) and their overall school achievement. The character strengths of zest, love of learning, perseverance, and social intelligence showed the strongest positive correlations with school-related positive affect. Teamwork, hope, self-regulation, and love were substantially negatively correlated with school-related negative affect. Certain character strengths showed positive relationships with positive school functioning and overall school achievement. A path model, testing the “engine model of well-being”, found—additionally to direct effects—indirect relationships between character strengths and positive school functioning (through school-related positive affect), which in turn leads to higher school achievement. The presented findings show character strengths as meaningful resources in the schooling context. Character strengths emerge to be crucial for students to experience school-related positive affect, which in turn supports students’ positive school functioning and their overall school achievement. The results demonstrate the complex interplay between students’ personality traits, affect, school functioning, and achievement at school.     

The Role of Non-Numerical Stimulus Features in Approximate Number System Training in Preschoolers from Low-Income Homes

Recent findings have suggested that adults’ and children’s approximate number system (ANS) acuity may be malleable through training, but research on ANS acuity has largely been conducted with adults and children who are from middle- to high-income homes. We conducted 2 experiments to test the malleability of ANS acuity in preschool-aged children from low-income homes and to test how non-numerical stimulus features affected performance. In Experiment 1, mixed-effects models indicated that children significantly improved their ratio achieved across training. Children’s change in probability of responding correctly across sessions was qualified by an interaction with surface area features of the arrays such that children improved their probability of answering correctly across sessions on trials in which numerosity conflicted with the total surface area of object sets significantly more than on trials in which total surface area positively correlated with numerosity. In Experiment 2, we found that children who completed ANS acuity training performed better on an ANS acuity task compared with children in a control group, but they only did so on ANS acuity trials in which numerosity conflicted with the total surface area of object sets. These findings suggest that training affects ANS acuity in children from low-income homes by fostering an ability to focus on numerosity in the face of conflicting non-numerical stimulus features.     

Transplanting brains?

Brain transplant thought experiments figure prominently in the debate on personal identity. Such hypotheticals are usually taken to provide support for psychological continuity theories. This standard interpretation has recently been challenged by Marya Schechtman. Simon Beck argues that Schechtman's critique rests upon ‘two costly mistakes’—claiming that (1) when evaluating these cases, philosophers mistakenly try to figure out the intuitions that they think people inhabiting such a possible world ought to have, instead of pondering their own intuitions. Beck further asserts that (2) brain transplant thought experiments cannot confirm any given theory of personal identity but rather they can only rule out theories. I argue on grounds of the social ontology of personhood that Beck has things back to front. Since our concept of personhood is shaped and informed by contingent de facto norms and structures of the natural world, and as such is heavily normatively laden, the conceptual genesis of personhood must be taken into account. This calls for constructing thought experiments as realistically as possible in order to trigger reliable intuitions. Furthermore, drawing on recent evidence from cognitive science, an empirically informed look at brain transplant thought experiments considering ‘Embodied Cognition’ reveals that Beck's arguments not only fall short for supporting psychological continuity theories, but also suggests an advantage of Schechtman's ‘Person Life View’.     

Predicting Cognitive and Social Consequences of Emotional Episodes: The Contribution of Emotional Intensity, the Five Factor Model, and Alexithymia

Emotional events are followed by recurrent thoughts (rumination) and talking about the event (social sharing of emotion). Factors that can account for variations in these consequences were examined (emotional intensity, the Five Factor Model, and two factors of alexithymia). In two samples, participants reported the most negative emotional event of recent months and in one sample also reported the most positive one. Results indicated that emotional intensity predicted social sharing and rumination, while neuroticism was positively related to intrusive thoughts about negative events and extraversion to rumination and social sharing about positive events. Difficulty describing feelings was negatively related to social sharing for negative events and reduced fantasy to rumination for positive events.     

From method to critique: a reply to Vonk and van Vliet

Vonk & van Vliet (1998) criticise the methods used in the study by Wagner, Elejabarrieta & Lahnsteiner (1995). They conclude that methodological flaws render some findings of the study invalid. It is shown that those flaws are in fact not present and that the remaining part of the conceptual critique is at least debatable. © 1998 John Wiley & Sons, Ltd.