Training-induced cognitive and neural plasticity

Peer Reviewe

Development and Plasticity of Cognitive Flexibility in Early and Middle Childhood

Cognitive flexibility, the ability to flexibly switch between tasks, is a core dimension of executive functions (EFs) allowing to control actions and to adapt flexibly to changing environments. It supports the management of multiple tasks, the development of novel, adaptive behavior and is associated with various life outcomes. Cognitive flexibility develops rapidly in preschool and continuously increases well into adolescence, mirroring the growth of neural networks involving the prefrontal cortex. Over the past decade, there has been increasing interest in interventions designed to improve cognitive flexibility in children in order to support the many developmental outcomes associated with cognitive flexibility. This article provides a brief review of the development and plasticity of cognitive flexibility across early and middle childhood (i.e., from preschool to elementary school age). Focusing on interventions designed to improve cognitive flexibility in typically developing children, we report evidence for significant training and transfer effects while acknowledging that current findings on transfer are heterogeneous. Finally, we introduce metacognitive training as a promising new approach to promote cognitive flexibility and to support transfer of training

Potential and limits of executive control training : age differences in the near and far transfer of task-switching training

Although executive functions can be improved by training, little is known about the extent to which these training-related benefits can be transferred to other tasks, or whether this transfer can be modulated by the type of training. This study investigated lifespan changes in near transfer of task-switching training to structurally similar tasks and its modulation by verbal self-instructions, feedback, and variable training, as well as far transfer to structurally dissimilar \u27executive\u27; tasks and fluid intelligence. Three age groups (8-10; 18-26; 62-76 years of age) were examined in a pretest-training-posttest design. Results showed near transfer of task-switching training in all age groups, especially in children and older adults. Near transfer was enhanced in adults and impaired in children when training tasks were variable. We also found substantial far transfer to other executive tasks and fluid intelligence in all age groups, pointing to the transfer of relatively general executive control abilities after training.Obwohl exekutive Funktionen durch Training verbessert werden können, weiß man bisher wenig darüber, inwieweit diese trainingsbedingten Verbesserungen auf andere Aufgabenübertragen werden können, oder ob dieser Transfer durch die Art des Trainings moduliert werden kann. Ziel der vorliegenden Studie war die die Untersuchung von Altersunterschieden im nahen Transfer von Aufgabenwechseltraining zu strukturell ähnlichen Trainingsaufgaben und die Modulation dieses Transfers durch verbale Selbstinstruktionen, Feedback und variables Training. Außerdem wurde weiter Transfer des Trainings zu strukturell unterschiedlichen "exekutiven Aufgaben" und anderen Aufgabenbereichen erforscht. Dazu wurden drei Altersgruppen (8-10, 18-26 und 62-76 Jahre) in einem Prätest - Training - Posttest Design untersucht. Die Ergebnisse zeigten nahen Transfer des Aufgabenwechseltrainings in allen Altersgruppen, aber besonders bei Kindern und älteren Erwachsenen. Im Gegensatz zu der Kindergruppe resultierte variables Training bei jungen und älteren Erwachsenen in einer Steigerung der Transferleistung. Darüber hinaus zeigten alle Altersgruppen weiten Transfer des Aufgabenwechseltrainings zu anderen exekutiven Aufgaben und fluider Intelligenz. Insgesamt weisen diese Ergebnisse auf den Transfer relativ genereller exekutiver Kontrollfähigkeiten hin

Action–effect learning in early childhood: does language matter?

Previous work showed that language has an important function for the development of action control. This study examined the role of verbal processes for action–effect learning in 4-year-old children. Participants performed an acquisition phase including a two-choice key-pressing task in which each key press (action) was followed by a particular sound (effect). Children were instructed to either (1) label their actions along with the corresponding effects, (2) verbalize task-irrelevant words, (3) or perform without verbalization. In a subsequent test phase, they responded to the same sound effects either under consistent or under inconsistent sound-key mappings. Evidence for action–effect learning was obtained only if action and effects were labeled or if no verbalization was performed, but not if children verbalized task-irrelevant labels. Importantly, action–effect learning was most pronounced when children verbalized the actions and the corresponding effects, suggesting that task-relevant verbal labeling supports the integration of event representations

Subliminal galvanic-vestibular stimulation influences ego- and object-centred components of visual neglect

Neglect patients show contralesional deficits in egocentric and object-centred visuospatial tasks. The extent to which these different phenomena are modulated by sensory stimulation remains to be clarified. Subliminal galvanic vestibular stimulation (GVS) induces imperceptible, polarity-specific changes in the cortical vestibular systems without the unpleasant side effects (nystagmus, vertigo) induced by caloric vestibular stimulation. While previous studies showed vestibular stimulation effects on egocentric spatial neglect phenomena, such effects were rarely demonstrated in object-centred neglect. Here, we applied bipolar subsensory GVS over the mastoids (mean intensity: 0.7. mA) to investigate its influence on egocentric (digit cancellation, text copying), object-centred (copy of symmetrical figures), or both (line bisection) components of visual neglect in 24 patients with unilateral right hemisphere stroke. Patients were assigned to two patient groups (impaired vs. normal in the respective task) on the basis of cut-off scores derived from the literature or from normal controls. Both groups performed all tasks under three experimental conditions carried out on three separate days: (a) sham/baseline GVS where no electric current was applied, (b) left cathodal/right anodal (CL/AR) GVS and (c) left anodal/right cathodal (AL/CR) GVS, for a period of 20. min per session. CL/AR GVS significantly improved line bisection and text copying whereas AL/CR GVS significantly ameliorated figure copying and digit cancellation. These GVS effects were selectively observed in the impaired- but not in the unimpaired patient group. In conclusion, subliminal GVS modulates ego- and object-centred components of visual neglect rapidly. Implications for neurorehabilitation are discussed

Can Task-Switching Training Enhance Executive Control Functioning in Children with Attention Deficit/-Hyperactivity Disorder?

The key cognitive impairments of children with attention deficit/-hyperactivity disorder (ADHD) include executive control functions such as inhibitory control, task-switching, and working memory (WM). In this training study we examined whether task-switching training leads to improvements in these functions. Twenty children with combined type ADHD and stable methylphenidate medication performed a single-task and a task-switching training in a crossover training design. The children were randomly assigned to one of two groups. One group started with the single-task training and then performed the task-switching training and the other group vice versa. The effectiveness of the task-switching training was measured as performance improvements (relative to the single-task training) on a structurally similar but new switching task and on other executive control tasks measuring inhibitory control and verbal WM as well as on fluid intelligence (reasoning). The children in both groups showed improvements in task-switching, that is, a reduction of switching costs, but not in performing the single-tasks across four training sessions. Moreover, the task-switching training lead to selective enhancements in task-switching performance, that is, the reduction of task-switching costs was found to be larger after task-switching than after single-task training. Similar selective improvements were observed for inhibitory control and verbal WM, but not for reasoning. Results of this study suggest that task-switching training is an effective cognitive intervention that helps to enhance executive control functioning in children with ADHD

“Hot” executive functions are comparable across monolingual and bilingual elementary school children: Results from a study with the Iowa Gambling Task

Past research found performance differences between monolingual and bilingual children in the domain of executive functions (EF). Furthermore, recent studies have reported advantages in processing efficiency or mental effort in bilingual adults and children. These studies mostly focused on the investigation of “cold” EF tasks. Studies including measures of “hot” EF, i.e., tasks operating in an emotionally significant setting, are limited and hence results are inconclusive. In the present study, we extend previous research by investigating performance in a task of the “hot” EF domain by both behavioral data and mental effort via pupillary changes during task performance. Seventy-three monolingual and bilingual school children (mean age = 107.23 months, SD = 10.26) solved the Iowa Gambling Task in two different conditions. In the standard task, characterized by constant gains and occasional losses, children did not learn to improve their decision-making behavior. In a reversed task version, characterized by constant losses and occasional gains, both monolinguals and bilinguals learned to improve their decision-making behavior over the course of the task. In both versions of the task, children switched choices more often after losses than after gains. Bilinguals switched their choices less often than monolinguals in the reversed task, indicating a slightly more mature decision-making strategy. Mental effort did not differ between monolinguals and bilinguals. Conclusions of these findings for the bilingual advantage assumption will be discussed

Changes in quality of life, depression, general anxiety, and heart-focused anxiety after defibrillator implantation

Aims The Anxiety-CHF (Anxiety in patients with Chronic Heart Failure) study investigated heart-focused anxiety (HFA, with the dimensions fear, attention, and avoidance of physical activity), general anxiety, depression, and quality of life (QoL) in patients with heart failure. Psychological measures were assessed before and up to 2 years after the implantation of an implantable cardioverter defibrillator (ICD) with or without cardiac resynchronization therapy defibrillator (CRT-D). Methods and results One hundred thirty-two patients were enrolled in this monocentric prospective study (44/88 CRT-D/ICD, mean age 61 ± 14 years, mean left ventricular ejection fraction 31 ± 9%, and 29% women). Psychological assessment was performed before device implantation as well as after 5, 12, and 24 months. After device implantation, mean total HFA, HFA-fear, HFA-attention, general anxiety, and QoL improved significantly. Depression and HFA-related avoidance of physical activity did not change. CRT-D patients compared with ICD recipients and women compared with men reported worse QoL at baseline. Younger patients (<median of 63 years) had higher levels of general anxiety and lower levels of HFA-avoidance at baseline than older patients. After 24 months, groups no longer differed from each other on these scores. Patients with a history of shock or anti-tachycardia pacing (shock/ATP; N = 19) reported no improvements in psychological measures and had significantly higher total HFA and HFA-avoidance levels after 2 years than participants without shock/ATP. Conclusions Anxiety and QoL improved after device implantation, and depression and HFA-avoidance remained unchanged. HFA may be more pronounced after shock/ATP. Psychological counselling in these patients to reduce HFA and increase physical activity should be considered

Age-related differentiation in verbal and visuo-spatial working memory processing in childhood

Working memory (WM), a key feature of the cognitive system, allows for maintaining and processing information simultaneously and in a controlled manner. WM processing continuously develops across childhood, with significant increases both in verbal and visuo-spatial WM. Verbal and visuospatial WM may show different developmental trajectories, as verbal (but not visuospatial) WM relies on internal verbal rehearsal, which is less developed in younger children. We examined complex VWM and VSWM performance in 125 younger (age 4 to 6 years) and 101 older (age 8 to10 years) children. Latent multi-group modeling showed that (1) older children performed better on both verbal and visuospatial WM span tasks than younger children, (2) both age groups performed better on verbal than visuospatial WM, and (3) a model with two factors representing verbal and visuospatial WM fit the data better than a one-factor model. Importantly, the correlation between the two factors was significantly higher in younger than in older children, suggesting an age-related differentiation of verbal and spatial WM processing in middle childhood. Age-related differentiation is an important characteristic of cognitive functioning and thus the findings contribute to our general understanding of WM processing