The Effect of Rewards and Punishments on Learning Action Selection and Execution Components of a Motor Skill

It is unknown whether rewards improve the capability to select appropriate targets for one’s movement (action selection) and/or the movement itself (action execution). Thus, we devised an experimental task wherein participants categorized a complex visual stimulus to determine toward which one of two targets to execute an action (putt a golf ball) on each trial under one of three conditions: reward, punishment, or neutral. After practicing the task under their assigned condition, participants performed an immediate, 24-hr, and 7-day post-test. Results revealed participants putted to the correct target more frequently during the post-tests than the first practice block, and putted more accurately during the post-tests than a pretest. However, the condition in which participants practiced did not moderate post-test performance (for either task component). Additionally, motivation scores explained action selection and action execution for the immediate post-test performance but not long-term retention, suggesting that motivation might be related to immediate performance, but not long-term learning. Further, the present task may be useful for researchers studying action selection and execution, since the task yielded learning effects that could be moderated by factors of interest.

THE INFLUENCE OF TDCS INTENSITY ON DECISION-MAKING TRAINING AND TRANSFER OUTCOMES

Transcranial direct current stimulation (tDCS) has been shown to improve single- and dual-task performance in healthy participants and enhance transferable training gains following multiple sessions of combined stimulation and task-practice. However, it has yet to be determined what the optimal stimulation dose is for facilitating such outcomes. We aimed to test the effects of different tDCS intensities, with a commonly used electrode montage, on performance outcomes in a multi-session single/dual-task training and transfer protocol. In a pre-registered study, 123 participants, who were pseudorandomised across four groups, each completed six sessions (pre- and post-training sessions and four combined tDCS and training sessions) and received 20 minutes of prefrontal anodal tDCS at 0.7 mA, 1.0 mA, 2.0 mA, or 15-second sham stimulation. Response time and accuracy were assessed in trained and untrained tasks. The 1.0 mA group showed substantial improvements in single-task reaction time and dual-task accuracy, with additional evidence for improvements in dual-task reaction times, relative to sham performance. This group also showed near transfer to the single-task component of an untrained multitasking paradigm. The 0.7 mA and 2.0 mA intensities varied in which performance measures they improved on the trained task, but in sum, the effects were less robust than for the 1.0 mA group and there was no evidence for the transfer of performance. Our study highlights that training performance gains are augmented by tDCS, but their magnitude and nature are not uniform across stimulation intensity.

Multiple midfrontal thetas revealed by source separation of simultaneous MEG and EEG

Theta-band (∼6 Hz) rhythmic activity within and over the medial prefrontal cortex (“midfrontal theta”) has been identified as a distinctive signature of “response conflict,” the competition between multiple actions when only one action is goal-relevant. Midfrontal theta is traditionally conceptualized and analyzed under the assumption that it is a unitary signature of conflict that can be uniquely identified at one electrode (typically FCz). Here we recorded simultaneous MEG and EEG (total of 328 sensors) in nine human subjects (7 female) and applied a feature-guided multivariate source-separation decomposition to determine whether conflict-related midfrontal theta is a unitary or multidimensional feature of the data. For each subject, a generalized eigendecomposition (GED) yielded spatial filters (components) that maximized the ratio between theta and broadband activity. Components were retained based on significance thresholding and midfrontal EEG topography. All of the subjects individually exhibited multiple (mean 5.89, SD 2.47) midfrontal components that contributed to sensor-level midfrontal theta power during the task. Component signals were temporally uncorrelated and asynchronous, suggesting that each midfrontal theta component was unique. Our findings call into question the dominant notion that midfrontal theta represents a unitary process. Instead, we suggest that midfrontal theta spans a multidimensional space, indicating multiple origins, but can manifest as a single feature at the sensor level due to signal mixing.Significance statement“Midfrontal theta” is a rhythmic electrophysiological signature of the competition between multiple response options. Midfrontal theta is traditionally considered to reflect a single process. However, this assumption could be erroneous due to “mixing” (multiple sources contributing to the activity recorded at a single electrode). We investigated the dimensionality of midfrontal theta by applying advanced multivariate analysis methods to a multimodal M/EEG dataset. We identified multiple topographically overlapping neural sources that drove response conflict-related midfrontal theta. Midfrontal theta thus reflects multiple uncorrelated signals that manifest with similar EEG scalp projections. In addition to contributing to the cognitive control literature, we demonstrate both the feasibility and the necessity of signal de-mixing to understand the neural dynamics underlying cognitive processes.

Executive Functioning as a Predictor of Weight Loss and Physical Activity Outcomes

Background Executive functioning, which is fundamental for carrying out goal-directed behaviors, may be an underappreciated predictor of outcomes in lifestyle modification programs for adults with obesity. Purpose This study tested the hypotheses that higher levels of baseline executive functioning would predict greater weight loss and physical activity after 6 months of behavioral treatment. Methods Participants (N = 320) were recruited from the community and provided with 16 treatment sessions. Executive functioning was measured with the tower task component of the Delis-Kaplan Executive Function System (D-KEFS). At months 0 and 6, weight was measured in the clinic and physical activity was measured with tri-axial accelerometers. Results Baseline D-KEFS achievement score, rule violations, and completion time significantly predicted weight loss at 6 months. For example, among participants without any rule violations (n = 162), weight loss averaged 11.0%, while those with rule violations (n = 158) averaged 8.7% weight loss. Rule violations also significantly predicted physical activity at 6 months. Among participants without any rule violations, physical activity at 6 months averaged 169.8 min/week, versus 127.2 min/week among those with rule violations. Conclusions Particular aspects of executive functioning may predict the relative ease or difficulty of changing eating and exercise-related behaviors, albeit with small effect sizes. This study is the first to our knowledge to detect a predictive relationship between components of executive functioning and objectively measured physical activity in adult lifestyle modification, and one of the first to predict weight loss in adults using an objective measure of executive functioning. ClinicalTrials.gov registration number NCT02363010

Efeito da associação de prática imagética e física na aprendizagem motora em crianças

Imagery training has been shown to induce motor learning in adults, but similar evidence in children is scarce. In this experiment, we aimed to evaluate the effect of association between imagery and physical practice compared to pure physical practice in the learning of a manual task in 9-10 year-old children. The task consisted of transporting a block and fitting it into a support with speed and steadiness, assessing movement time to complete the “reaching” and “transport” task components. The children were assigned to one of three groups: (a) physical practice (PHYS) (240 trials), (b) combination (COMB) of imagery (180 trials) and physical (60 trials) practice, and (c) control (CON), associating visual rotation (180 trials) and physical practice (60 trials). Performance was evaluated immediately and 24 h after practice. Results indicated that the PHYS group achieved a persistent performance gain in the “transport”, but not in the “reaching” task component, while the COMB group achieved persistent performance gains in both movement components; no significant differences were found for the CON group. Our results suggest that imagery training improves the task mental representation in children, while physical practice provides sensory feedback on the performed movements. As a conclusion, the results suggest that combination of imagery and physical practice can be more effective than pure physical practice for children’s motor learning.

Handedness results from complementary hemispheric dominance, not global hemispheric dominance: evidence from mechanically coupled bilateral movements

Two contrasting views of handedness can be described as 1) complementary dominance, in which each hemisphere is specialized for different aspects of motor control, and 2) global dominance, in which the hemisphere contralateral to the dominant arm is specialized for all aspects of motor control. The present study sought to determine which motor lateralization hypothesis best predicts motor performance during common bilateral task of stabilizing an object (e.g., bread) with one hand while applying forces to the object (e.g., slicing) using the other hand. We designed an experimental equivalent of this task, performed in a virtual environment with the unseen arms supported by frictionless air-sleds. The hands were connected by a spring, and the task was to maintain the position of one hand while moving the other hand to a target. Thus the reaching hand was required to take account of the spring load to make smooth and accurate trajectories, while the stabilizer hand was required to impede the spring load to keep a constant position. Right-handed subjects performed two task sessions (right-hand reach and left-hand stabilize; left-hand reach and right-hand stabilize) with the order of the sessions counterbalanced between groups. Our results indicate a hand by task-component interaction such that the right hand showed straighter reaching performance whereas the left hand showed more stable holding performance. These findings provide support for the complementary dominance hypothesis and suggest that the specializations of each cerebral hemisphere for impedance and dynamic control mechanisms are expressed during bilateral interactive tasks. NEW & NOTEWORTHY We provide evidence for interlimb differences in bilateral coordination of reaching and stabilizing functions, demonstrating an advantage for the dominant and nondominant arms for distinct features of control. These results provide the first evidence for complementary specializations of each limb-hemisphere system for different aspects of control within the context of a complementary bilateral task.

Advances in Neuropsychological Assessment of Attention

Attention is one of the most basic cognitive processes and is a prerequisite for the use of more complex functions, since it is not possible to evaluate perception or memory processes without keeping in mind attention issues (Amador, Forns, & Kirchner, 2006). The ability to maintain an appropriate level of attention is basic for education and learning, especially during childhood and school age. With the aim of studying attention separately from other cognitive functions, the so-called continuous performance tests (CPT) were created. The first series of CPTs were developed by Rosvold, Mirsky, Sarason, Bransome, and Beck (1956) to study vigilance in adults with acquired brain injury (Riccio, Reynolds, & Lowe, 2001), more specifically, persons with seizures (Amador, Forns, & Kirchner, 2006). Nowadays, CPTs are still one of the most widely used measures for the assessment of attention and processing speed. Briefly, it can be said that a CPT is a group of paradigms to evaluate attention, inhibitory response or disinhibition (a component of executive control that provides information about the subject’s impulsivity), and processing speed. Basically, CPTs rely on the rapid, random presentation of a series of stimuli to which the subject must respond following instructions given at the beginning of the test. The main value of CPTs is their empirical support. Diverse CPT paradigms have consistently demonstrated their sensitivity for a great variety of both neurological and psychiatric disorders, in adults and in children. Frequently, CPTs also use a continuous vigilance task, in order to obtain quantitative information about the individual’s ability to sustain attention in time. From its creation, the CPT paradigm has been used with many variants of its task component. Greenberg and Walkman (1993) found up to 100 different versions of CPT in use. Historically, when Rosvold and his collaborators introduced the test, they had the goal of measuring correct answers provided by the subject as an indicator of selective attention. With subsequent experimentation, other measures, such as processing speed, impulsivity, inattention, and sustained attention, divided or alternate, have been included.

Stress Enhances the Memory-Degrading Effects of Eye Movements on Emotionally Neutral Memories

Eye movement desensitization and reprocessing is an effective treatment for posttraumatic stress disorder. It uses a dual-task approach: Patients retrieve traumatic memories while making lateral eye movements. Laboratory studies have consistently shown that this dual-task component decreases the vividness of emotional memories, whereas neutral memories appear insensitive to the intervention. Hence, emotional arousal might play a crucial role in the (re)consolidation of the degraded memory. This study investigated whether boosting arousal levels would induce degradation of neutral memories by dual tasking. A total of 67 participants, 32 with performance anxiety, selected two vivid, neutral autobiographical memories, which were subjected to dual tasking or recall only. Half of the participants first underwent the Trier Social Stress Task to increase arousal. Only participants with performance anxiety in the arousal condition showed reduced vividness after the dual tasking relative to recall only. Thus, adding arousal to neutral memories makes them susceptible to the degrading effects of dual tasking.

Developing English Speaking Learning Materials for Saturday English School Program

This study aims at (1) identifying the target needs, and learning needs of students, (2) developing appropriate English speaking learning materials for grade VII students of SES Program at SMPIT ABY. This research was a research and development study consisting of seven steps: needs analysis, developing course grid, developing first draft, getting the expert judgment, trying out the materials, evaluating and revising the materials, and writing the final draft. The subjects were grade VII students of SES Program at SMPIT ABY. The data were collected using questionnaires and an interview guide. The results found that the target needs of grade VII students of SES program at SMPIT ABY are the English speaking learning materials which are related to Islamic contents. Their learning needs are related to the goal, input, setting, procedure, teachers’ role, and students’ role. Four units were developed based on the target and learning needs. The interval mean value of each task component in all units of the developed materials is between 2.52< Ẍ ≤ 3.27and 3.28 < Ẍ ≤ 4.03. This indicates that, the materials are appropriate to grade VII students of SES Program at SMPIT ABY.Keywords: speaking, learning materials and saturday English school program

Working outside of your wheelhouse: Effects of incentives and framing on transactive memory systems and performance

People collaborate to address tasks that can often be decomposed into smaller components. These components beg different forms of expertise and may differ in value to the group. We show that transactive memory structure is affected by the interaction between task component value, incentive framing (i.e., whether task incentives take the form of gains or losses), and the distribution of expertise with respect to task components. We find that when groups include a member with expertise in a highly valuable task component, that member is exceptionally motivated and puts forth high levels of effort. Only groups with such an expert successfully realized the potential performance benefit associated with high-value domains. Groups recalled more items under loss framing than under gains framing, but only when the potential losses were low and constant across components. We integrate our findings into the extant literatures on transactive memory and gains/loss framing.