Chung Yen Looi

Combining brain stimulation and video game to promote long-term transfer of learning and cognitive enhancement

Cognitive training offers the potential for individualised learning, prevention of cognitive decline, and rehabilitation. However, key research challenges include ecological validity (training design), transfer of learning and long-term effects. Given that cognitive training and neuromodulation affect neuroplasticity, their combination could promote greater, synergistic effects. We investigated whether combining transcranial direct current stimulation (tDCS) with cognitive training could further enhance cognitive performance compared to training alone, and promote transfer within a short period of time. Healthy adults received real or sham tDCS over their dorsolateral prefrontal cortices during two 30-minute mathematics training sessions involving body movements. To examine the role of training, an active control group received tDCS during a non-mathematical task. Those who received real tDCS performed significantly better in the game than the sham group, and showed transfer effects to working memory, a related but non-numerical cognitive domain. This transfer effect was absent in active and sham control groups. Furthermore, training gains were more pronounced amongst those with lower baseline cognitive abilities, suggesting the potential for reducing cognitive inequalities. All effects associated with real tDCS remained 2 months post-training. Our study demonstrates the potential benefit of this approach for long-term enhancement of human learning and cognition.

Transcranial random noise stimulation and cognitive training to improve learning and cognition of the atypically developing brain: A pilot study

Learning disabilities that affect about 10% of human population are linked to atypical neurodevelopment, but predominantly treated by behavioural interventions. Behavioural interventions alone have shown little efficacy, indicating limited success in modulating neuroplasticity, especially in brains with neural atypicalities. Even in healthy adults, weeks of cognitive training alone led to inconsistent generalisable training gains, or “transfer effects” to non-trained materials. Meanwhile, transcranial random noise stimulation (tRNS), a painless and more direct neuromodulation method was shown to further promote cognitive training and transfer effects in healthy adults without harmful effects. It is unknown whether tRNS on the atypically developing brain might promote greater learning and transfer outcomes than training alone. Here, we show that tRNS over the bilateral dorsolateral prefrontal cortices (dlPFCs) improved learning and performance of children with mathematical learning disabilities (MLD) during arithmetic training compared to those who received sham (placebo) tRNS. Training gains correlated positively with improvement on a standardized mathematical diagnostic test, and this effect was strengthened by tRNS. These findings mirror those in healthy adults, and encourage replications using larger cohorts. Overall, this study offers insights into the concept of combining tRNS and cognitive training for improving learning and cognition of children with learning disabilities.

OP 6. Stimulating the brain while playing a computer-based maths game to enhance domain-specific and domain-general cognitive abilities

Introduction Effective processing of the spatial representation of number magnitude is crucial for the development of mathematical skills. Recent research has shown that: (1) bodily spatial experiences of number magnitude resulted in pronounced improvement in numerical development [1] , and (2) competence with fractions predicted gains in mathematical achievement [2] . Objectives We examined here whether cognitive training that included these components coupled with transcranial direct current stimulation (tDCS) could: (1) affect mathematical performance during training; and (2) impact other cognitive functions that are involved in mathematics such as working memory. Materials and methods We designed an adaptive computer-based mathematics game which combined a motion-sensing input device (KINECT™, Microsoft) with wireless tDCS (StarStim, NeuroElectrics) ( Fig. 1 ). We delivered anodal tDCS to the right dorsolateral prefrontal cortex (DLPFC), and cathodal tDCS to the left DLPFC to modulate neuronal excitability and neuroplasticity during the mathematical game. Twenty participants completed two 30-min training sessions on two separate days. They indicated the location of fractions on a visually presented number line by physically moving side-to-side. Trial difficulty increased as a function of performance. Results Compared to sham stimulation, TDCS led to more accurate performance and faster reaction times at higher levels of difficulty. One of the important effects was a dissociation between the success in the game (the highest level reached at the end of training) and mathematical abilities before starting the game ( Fig. 2 ). While the predicted pattern of positive correlation between success in the game and mathematical ability were observed for sham stimulation, in the case of tDCS a negative correlation was observed. Namely, in the tDCS group, those who had lower mathematical abilities were able improve more (i.e., as shown by the levels raised) than those how had higher mathematical abilities prior to training. In addition, tDCS led to a transfer effect in which participants who received tDCS showed after the training a significant increase in verbal working memory performance compared to the sham group, but not on visuospatial working memory. Conclusion Our unique combination of a computer-based mathematics game and brain stimulation has shown to lead to enhanced performance during the training, with an effect on verbal working memory after the completion of the training. In addition, the results indicate the efficacy of tDCS in improving the performance especially of those with less competent mathematical abilities, therefore having important neuroscientific, societal, educational and ethical implications.

The Use of Transcranial Direct Current Stimulation for Cognitive Enhancement

Public and academic debate on the use of noninvasive brain stimulation techniques such as transcranial direct current stimulation (tDCS) as cognitive enhancement proper is on the rise. Critically, the use of such a new approach is contingent on the evidence of its safety, beneficial effects, and its cost-to-benefit ratio at the individual and societal levels. In this chapter we review the basic mechanisms and physiological effects of tDCS, as well as its effects on human cognition across the developmental spectrum in children, adults, and the elderly, in sickness and in health. Then we highlight the parameters that could be further optimized for more effective cognitive enhancement. Finally, we present some of the stimulating and open questions on the future use of tDCS for cognitive enhancement.

Transcranial Electrical Stimulation to Enhance Cognitive Abilities in the Atypically Developing Brain

Individuals with developmental learning disabilities and behavioral disorders show structural and functional abnormalities in certain brain areas, and suffer with severe educational and career consequences. Cognitive interventions show only limited success for improvement. In order to alleviate the burden on the affected individual and the society as a whole, we need to target these neural deficits. Transcranial electrical stimulation (tES), with its large variety of methods to enhance and decrease cortical excitability, is a promising tool to achieve improvements at both brain and behavioral levels. Here we discuss the current options for stimulation and the biological effects, and how these can be applied in some examples of cognitive and behavioral deficits. We also note the importance of safety guidelines and careful assessment in preclinical studies, as well as in clinical pediatric populations, as the evidence in these cases is currently minimal. Overall, we suggest that tES can have the capacity to redirect atypical brain development and have a positive impact on educational difficulties. Future developments in the optimization of training and stimulation parameters might allow us to remove the neural brakes on learning in a variety of child developmental disorders.

The neurocognitive architecture of individual differences in math anxiety in typical children

Math Anxiety (MA) is characterized by a negative emotional response when facing math-related situations. MA is distinct from general anxiety and can emerge during primary education. Prior studies typically comprise adults and comparisons between high- versus low-MA, where neuroimaging work has focused on differences in network activation between groups when completing numerical tasks. The present study used voxel-based morphometry (VBM) to identify the structural brain correlates of MA in a sample of 79 healthy children aged 7–12 years. Given that MA is thought to develop in later primary education, the study focused on the level of MA, rather than categorically defining its presence. Using a battery of cognitive- and numerical-function tasks, we identified that increased MA was associated with reduced attention, working memory and math achievement. VBM highlighted that increased MA was associated with reduced grey matter in the left anterior intraparietal sulcus. This region was also associated with attention, suggesting that baseline differences in morphology may underpin attentional differences. Future studies should clarify whether poorer attentional capacity due to reduced grey matter density results in the later emergence of MA. Further, our data highlight the role of working memory in propagating reduced math achievement in children with higher MA.

Publisher Correction: The Neurocognitive Architecture of Individual Differences in Math Anxiety in Typical Children

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

The Neurochemistry of Mathematical Genius: Reduced Frontal Excitation/Inhibition Balance in an Expert Calculator

Alterations in excitatory and inhibitory neurotransmitters (glutamate and GABA, respectively) have been found in various neuropsychiatric disorders, but have not been examined in individuals with prodigious cognitive abilities. Understanding exceptional brain processing is critical for developing biomedical interventions for cognitive and neurodevelopmental atypicalities. We tested the 11-fold world champion in mental calculation, G.M., and compared his right middle frontal gyrus, which has been associated with mathematical prodigy, to four healthy control expert calculators, who were not prodigies. We found substantially lower frontal glutamate/GABA compared to non-prodigy controls, but not glutamate or GABA individually, measured with magnetic resonance spectroscopy. We suggest that prefrontal glutamate/GABA is a potential marker of extraordinary cognitive skills.