Once more on the equilibrium-point hypothesis (lambda model) for motor control

The equilibrium control hypothesis (lambda model) is considered with special reference to the following concepts: (a) the length-force invariant characteristic (IC) of the muscle together with central and reflex systems subserving its activity; (b) the tonic stretch reflex threshold (lambda) as an independent measure of central commands descending to alpha and gamma motoneurons; (c) the equilibrium point, defined in terms of lambda, IC and static load characteristics, which is associated with the notion that posture and movement are controlled by a single mechanism; and (d) the muscle activation area (a reformulation of the "size principle")--the area of kinematic and command variables in which a rank-ordered recruitment of motor units takes place. The model is used for the interpretation of various motor phenomena, particularly electromyographic patterns. The stretch reflex in the lambda model has no mechanism to follow-up a certain muscle length prescribed by central commands. Rather, its task is to bring the system to an equilibrium, load-dependent position. Another currently popular version defines the equilibrium point concept in terms of alpha motoneuron activity alone (the alpha model). Although the model imitates (as does the lambda model) spring-like properties of motor performance, it nevertheless is inconsistent with a substantial data base on intact motor control. An analysis of alpha models, including their treatment of motor performance in deafferented animals, reveals that they suffer from grave shortcomings. It is concluded that parameterization of the stretch reflex is a basis for intact motor control. Muscle deafferentation impairs this graceful mechanism though it does not remove the possibility of movement.     

Variations on active learning

Although current theories of memory emphasize the fact that learning is an active process, there is little consensus on the role of active learning. This paper attempts to provide a more precise characterization of active learning in the acquisition of computer skills. The analysis of verbal protocols suggests that active learning varies on at least two dimensions: schema orientation and learning strategy. Schema orientation refers to the type of information the learner is acquiring and varies from relational information to procedural information. Learning strategy describes how the information is acquired. Some people prefer to be internally driven and form their own plans for learning. Others are externally driven and allow the instructional materials to guide their learning. These differences need to be taken into account in describing learning and in designing instructional materials.     

Simulation analyses of space use: Home range estimates,variability, and sample size

Simulations of space use by animals were run to determine the relationship among home range area estimates, variability, and sample size (number of locations). As sample size increased, home range size increased asymptotically, whereas variability decreased among mean home range area estimates generated by multiple simulations for the same sample size. Our results suggest that field workers should ascertain between 100 and 200 locations in order to estimate reliably home range area. In some cases, this suggested guideline is higher than values found in the few published studies in which the relationship between home range area and number of locations is addressed. Sampling differences for small species occupying relatively small home ranges indicate that fewer locations may be sufficient to allow for a reliable estimate of home range. Intraspecific variability in social status (group member, loner, resident, transient), age, sex, reproductive condition, and food resources also have to be considered, as do season, habitat, and differences in sampling and analytical methods. Comparative data still are needed.     

The Challenges of Cotherapy

Why use cotherapy? No justification can be found in the outcome literature, but the literature is not sufficiently sophisticated to address the issue adequately. Cotherapy might be chosen when the therapy is difficult, when role modelling is called for, or when a relationship is needed to soak up projections. It may be chosen primarily for the benefit of the therapists, though as a teaching format it has drawbacks. The relationships developed between cotherapists may be challenging and benefit from supervision. They may be understood by analogy to other relationships, e.g. marriage, and the therapeutic alliance between therapist and patient. The technical pros and cons of cotherapy call for systematic study. In general, though, a case can be made for the use of cotherapy, and for other procedures such as live supervision, as ways of influencing the therapeutic culture for the better.     

Telehealth parent training for a young child at risk for autism spectrum disorder

The global pandemic has highlighted the importance of telehealth to access behavioral interventions. Face-to-face parent training improves the development and behaviors of young children at risk for autism spectrum disorder (ASD). We evaluated a telehealth parent training intervention for a child at risk for ASD. Two parents identified possible early ASD symptoms in their 30-month-old son (lack of imitation, pointing, and vocal manding). Both parents simultaneously received telehealth behavioral skills training on the Parent Intervention for Children at Risk for Autism program for 1 hour per week over 29 weeks. Multiple baseline designs across parent and child behaviors showed that both parents improved their parent teaching fidelity above 80% and the child improved on all trained behaviors. This study expands the utility of telehealth behavioral parent training to young children at risk for ASD to mitigate early symptoms of ASD.     

Evolution and trends in consumer behaviour: Insights from Journal of Consumer Behaviour

The way consumers behave is fundamental to marketing. Journal of Consumer Behaviour (JCB) is an international journal dedicated to publishing the latest developments of consumer behaviour. To gain an understanding of the evolution and trends in consumer behaviour, this study presents a retrospective review of JCB using bibliometric analysis. Using bibliographic records of JCB from Scopus, this study finds that consumer behaviour research in JCB has grown substantially in terms of collaboration (co-authorships), global reach (countries), productivity (publications), and impact (citations). The major themes explored by consumer behaviour research in JCB include consumer information processing, consumption communities, consumption value, sustainable consumption, intergenerational consumer behaviour, consumer-brand relationship, consumer ethics, and conditional relationships in consumer behaviour. The most recent consumer behaviour research in JCB has considered externalities such as the COVID-19 pandemic and focused on themes such as consumer ethics and sustainable consumption in line with the global movement toward environmental social governance (ESG) and sustainable development goals (SDGs).     

Susceptibility to prosocial and antisocial influence in adolescence following mindfulness training

Mindfulness training programmes have shown to encourage prosocial behaviours and reduce antisocial tendencies in adolescents. However, less is known about whether training affects susceptibility to prosocial and antisocial influence. The current study investigated the effect of mindfulness training (compared with an active control) on self-reported prosocial and antisocial tendencies and susceptibility to prosocial and antisocial influence. 465 adolescents aged 11–16 years were randomly allocated to one of two training programmes. Pre- and post-training, participants completed a social influence task. Self-reported likelihood of engaging in prosocial and antisocial behaviours did not change post-training, and regardless of training group, participants showed a higher propensity for prosocial influence than for antisocial influence. Finally, participants were less influenced by antisocial ratings following both training programmes.