Gray matter volumetric changes with a challenging adaptive cognitive training program based on the dual n-back task

Comparative Efficacy of Cognitive Training for Post-Stroke Aphasia: A Systematic Review and Network Meta-Analysis

BACKGROUND

Although cognitive training has shown potential for treating post-stroke aphasia (PSA), its efficacy varies across studies, and the optimal training approaches remain unclear.

OBJECTIVE

To evaluate and compare the effects of distinct cognitive training interventions, either combined with or independent of speech and language therapy (SLT), on language function in individuals with PSA.

METHODS

A systematic search encompassing PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure, Wanfang, VIP, and Chinese Biomedical Databases was conducted for randomized controlled trials (RCTs). A network meta-analysis evaluated interventions, including computer-assisted cognitive training (CCT), conventional cognitive training (CT), virtual reality (VR)-based cognitive training (vrCT), telerehabilitation computer-assisted cognitive training (tCCT), working memory (WM) training, and attention training (AT).

RESULTS

Eleven RCTs comprising 501 participants were included. Individuals with PSA who underwent combined WM training with SLT led to significantly enhanced Western Aphasia Battery (WAB) Aphasia Quotient (AQ), as well as in spontaneous speech, auditory comprehension, repetition, and naming, compared to those receiving SLT alone. This combination was more effective than both CCT with SLT and tCCT with SLT in improving WAB AQ. Similarly, it outperformed both CCT with SLT and vrCT with SLT in enhancing WAB spontaneous speech. Additionally, both AT and CT combined with SLT were more effective than SLT alone in enhancing WAB spontaneous speech. Specifically, AT combined with SLT proved more effective than vrCT with SLT in this area. Moreover, vrCT combined with SLT significantly improved auditory comprehension compared with SLT alone.

CONCLUSIONS

Combining WM training and SLT and integrating vrCT with SLT both significantly enhance language function in individuals with PSA, compared with SLT alone. Our findings advocate for the use of these cognitive training approaches as promising strategies for language rehabilitation in this population. PROSPERO registration number: CRD42023462361.

Effects of computerized working memory training on neuroplasticity in healthy individuals: A combined neuroimaging and neurotransmitter study

Working memory (WM) is an essential cognitive function that underpins various higher-order cognitive processes. Improving WM capacity through targeted training interventions has emergered as a potential approach for enhancing cognitive abilities. The present study employed an 8-week regimen of computerized WM training (WMT) to investigate its effect on neuroplasticity in healthy individuals, utilizing neuroimaging data gathered both before and after the training. The key metrics assessed included the amplitude of low-frequency fluctuations (ALFF), voxel-based morphometry (VBM), and the spatial distribution correlations of neurotransmitter. The results indicated that post-training, compared to baseline, there was a reduction in ALFF in the medial superior frontal gyrus and an elevation in ALFF in the left middle occipital gyrus within the training group. In comparison to the control group, the training group also exhibited decreased ALFF in the anterior cingulate cortex, angular gyrus, and superior parietal lobule, along with increased ALFF in the postcentral gyrus post-training. VBM analysis revealed a significant increase in gray matter volume (GMV) in the right dorsal superior frontal gyrus after the training period, compared to the initial baseline measurement. Furthermore, the training group showed GMV increases in the dorsal superior frontal gyrus, Rolandic operculum, precentral gyrus, and postcentral gyrus when compared to the control group. In addition, significant associations were identifed between neuroimaging measurements (AFLL and VBM) and the spatial patterns of neurotransmitters such as serotonin (5-HT), dopamine (DA), and N-methyl-D-aspartate (NMDA), providing insights into the underlying neurochemical processes. These findings clarify the neuroplastic changes caused by WMT, offering a deeper understanding of brain plasticity and highlighting the potential advantages of cognitive training interventions.

White matter integrity of right frontostriatal circuit predicts internet addiction severity among internet gamers

Excessive use of the internet, which is a typical scenario of self-control failure, could lead to potential consequences such as anxiety, depression, and diminished academic performance. However, the underlying neuropsychological mechanisms remain poorly understood. This study aims to investigate the structural basis of self-control and internet addiction. In a cohort of 96 internet gamers, we examined the relationships among grey matter volume and white matter integrity within the frontostriatal circuits and internet addiction severity, as well as self-control measures. The results showed a significant and negative correlation between dACC grey matter volume and internet addiction severity (p < 0.001), but not with self-control. Subsequent tractography from the dACC to the bilateral ventral striatum (VS) was conducted. The fractional anisotropy (FA) and radial diffusivity of dACC-right VS pathway was negatively (p = 0.011) and positively (p = 0.020) correlated with internet addiction severity, respectively, and the FA was also positively correlated with self-control (p = 0.036). These associations were not observed for the dACC-left VS pathway. Further mediation analysis demonstrated a significant complete mediation effect of self-control on the relationship between FA of the dACC-right VS pathway and internet addiction severity. Our findings suggest that the dACC-right VS pathway is a critical neural substrate for both internet addiction and self-control. Deficits in this pathway may lead to impaired self-regulation over internet usage, exacerbating the severity of internet addiction.

Experiences of cognitive training on primary breast cancer survivor's cognitive impairments at work: A longitudinal qualitative study

OBJECTIVES

Cancer-related cognitive impairment (CRCI) is associated with adverse work-related outcomes in women living with a history of primary breast cancer. We explored the perceived impact of receiving adaptive cognitive training (dual n-back training) or active control training (dual 1-back training) on CRCI. Furthermore, we explored the perceived transfer effects of cognitive training on work-related self-management methods for cognitive impairment and work-related outcomes such as career development.

DESIGN

Longitudinal qualitative study.

METHODS

A 'framework' analysis approach was used to analyse semi-structured telephone interviews completed by women with a history of primary breast cancer before training (N = 40), one month (N = 30) and six months (N = 29) post-training.

RESULTS

Four main themes were identified: (1) impact of cognitive impairment at work, (2) perceived impact of cognitive training on impaired cognitive function, (3) perceived effects of training on work-related self-management methods for cognitive impairment and (4) perceived impact on women's career development and progression. Compared to baseline, women who received adaptive dual n-back training reported sustained improvement in multiple cognitive domains including memory and attention up to six months post-training when the follow-up interviews were conducted. Perceived improvements in cognitive function were associated with greater self-confidence and better emotional well-being in work. These improvements were found to lower dependency on self-management methods for cognitive impairment and enhance effectiveness as well as prompt career development or progression for many women. Although some findings of a similar nature were reported in the active control dual 1-back training group the perceived effects were more pronounced and consistent in the dual n-back group.

CONCLUSIONS

Adaptive cognitive training (dual n-back training) improves perceived CRCI experienced by women in the workplace, enhancing their self-confidence and general emotional well-being. These perceived improvements, in turn, can decrease reliance on self-management methods for cognitive impairment and improve work efficiency and contribute to career development and progression.

Right Fusiform Gray Matter Volume in Children with Long-Term Abacus Training Positively Correlates with Arithmetic Ability

Abacus-based mental calculation (AMC) training has a positive effect on number-related cognitive abilities. While visuospatial strategy may distinguish AMC from conventional calculation method, the underlying neural mechanism is still elusive. The current study aimed to address this question by examining the plasticity of fusiform induced by AMC training and whether this training affects the association between the volume of fusiform and behavioral performance in numerical cognitive tasks using voxel-based morphometry analysis. The results showed that gray matter volumes of bilateral fusiform were significantly smaller in the AMC group relative to the control group. In addition, the volume of right fusiform was positively correlated with digit memory span and negatively correlated with reaction time of an arithmetic operation task only within the AMC group. These results indicate that bilateral fusiform may be the essential neural substrate for AMC experts to recognize and reconstruct abacus-based representations for numbers. These results may advance our understanding of the neural mechanisms of AMC and shield some lights to potential interactions between brain development and cognitive training in children.

Plasticity of the resting-state brain: static and dynamic functional connectivity change induced by divergent thinking training

Creativity is very important and is linked to almost all areas of our everyday life. Improving creativity brings great benefits. Various strategies and training paradigms have been used to stimulate creative thinking. These training approaches have been confirmed to be effective. However, whether or not training can reshape the resting-state brain is still unclear. The present study examined whether or not the divergent thinking training intervention can reshape the resting-state brain functional connectivity (FC). Static seed-based and dynamic approaches were used to explore this problem. Results demonstrate significant changes in static and dynamic FCs. FCs, such as dorsal anterior cingulate cortex-inferior parietal lobule, dorsal anterior cingulate cortex-precuneus and left and right dorsolateral prefrontal cortex, was significantly improved through the training. Furthermore, the temporal variability of the supplementary motor area and middle temporal gyrus was improved. These results indicate that divergent thinking training may lead to resting-state brain plasticity. Considering the role of these regions in brain networks, the present study further confirms the close relationship between the brain networks' dynamic interactions and divergent thinking processes.

Cortical and subcortical responsiveness to intensive adaptive working memory training: An MRI surface-based analysis

Working memory training (WMT) has been shown to have effects on cognitive performance, the precise effects and the underlying neurobiological mechanisms are, however, still a matter of debate. In particular, the impact of WMT on gray matter morphology is still rather unclear. In the present study, 59 healthy middle‐aged participants (age range 50–65 years) were pseudo‐randomly single‐blinded allocated to an 8‐week adaptive WMT or an 8‐week nonadaptive intervention. Before and after the intervention, high resolution magnetic resonance imaging (MRI) was performed and cognitive test performance was assessed in all participants. Vertex‐wise cortical volume, thickness, surface area, and cortical folding was calculated. Seven subcortical volumes of interest and global mean cortical thickness were also measured. Comparisons of symmetrized percent change (SPC) between groups were conducted to identify group by time interactions. Greater increases in cortical gyrification in bilateral parietal regions, including superior parietal cortex and inferior parietal lobule as well as precuneus, greater increases in cortical volume and thickness in bilateral primary motor cortex, and changes in surface area in bilateral occipital cortex (medial and lateral occipital cortex) were detected in WMT group after training compared to active controls. Structural training‐induced changes in WM‐related regions, especially parietal regions, might provide a better brain processing environment for higher WM load.

Sustained and transient gray matter volume changes after n-back training: A VBM study

Working memory training causes functional adaptations in the brain, which include changes in activation and functional connectivity that remain stable over time. Few studies have investigated gray matter (GM) changes after working memory training, and they have produced heterogeneous results without clarifying the stable effects of training. The present study was designed to test for sustained and transient anatomic changes after only 200 min of working memory training. The voxel-based morphometry technique was used in order to investigate the GM changes produced by a brief single n-back training, immediately and 5 weeks after finishing it. The sample was composed by 59 human participants who underwent MRI scanning and were assigned to either a training group or a passive control group. Results showed sustained GM volume enlargement in the right superior parietal cortex and a transient GM decrease in the right putamen. The brain adaptation in the right superior parietal cortex was stronger in individuals who showed greater improvements in performance. The results provide further evidence that a brief working memory training is able to produce brain plasticity in structures related to the trained task.

Enhancing Intelligence: From the Group to the Individual

Research aimed at testing whether short-term training programs can enhance intelligence is mainly concentrated on behavior. Expected positive effects are found sometimes, but the evidence is far from conclusive. It is assumed that training must evoke changes in the brain for observing genuine improvements in behavior. However, behavioral and brain data are seldom combined in the same study. Here we present one example of this latter type of research summarizing, discussing, and integrating already published results. The training program was based on the adaptive dual n-back task, and participants completed a comprehensive battery measuring fluid and crystallized ability, along with working memory and attention control, before and after training. They were also submitted to MRI scanning at baseline and post-training. Behavioral results revealed positive effects for visuospatial processing across cognitive domains. Brain imaging data were analyzed by longitudinal voxel-based morphometry, tensor-based morphometry, surface-based morphometry, and structural connectivity. The integration of these multimodal brain results provides clues about those observed in behavior. Our findings, along with previous research and current technological advances, are considered from the perspective that we now live in ideal times for (a) moving from the group to the individual and (b) developing personalized training programs.

Enhanced structural connectivity within a brain sub-network supporting working memory and engagement processes after cognitive training

The structural connectome provides relevant information about experience and training-related changes in the brain. Here, we used network-based statistics (NBS) and graph theoretical analyses to study structural changes in the brain as a function of cognitive training. Fifty-six young women were divided in two groups (experimental and control). We assessed their cognitive function before and after completing a working memory intervention using a comprehensive battery that included fluid and crystallized abilities, working memory and attention control, and we also obtained structural MRI images. We acquired and analyzed diffusion-weighted images to reconstruct the anatomical connectome and we computed standardized changes in connectivity as well as group differences across time using NBS. We also compared group differences relying on a variety of graph-theory indices (clustering, characteristic path length, global and local efficiency and strength) for the whole network as well as for the sub-network derived from NBS analyses. Finally, we calculated correlations between these graph indices and training performance as well as the behavioral changes in cognitive function. Our results revealed enhanced connectivity for the training group within one specific network comprised of nodes/regions supporting cognitive processes required by the training (working memory, interference resolution, inhibition, and task engagement). Significant group differences were also observed for strength and global efficiency indices in the sub-network detected by NBS. Therefore, the connectome approach is a valuable method for tracking the effects of cognitive training interventions across specific sub-networks. Moreover, this approach allowsfor the computation of graph theoretical network metricstoquantifythetopological architecture of the brain networkdetected. The observed structural brain changes support the behavioral results reported earlier (see Colom, Román, et al., 2013).

Brain structural changes following adaptive cognitive training assessed by Tensor-Based Morphometry (TBM)

Tensor-Based Morphometry (TBM) allows the automatic mapping of brain changes across time building 3D deformation maps. This technique has been applied for tracking brain degeneration in Alzheimer's and other neurodegenerative diseases with high sensitivity and reliability. Here we applied TBM to quantify changes in brain structure after completing a challenging adaptive cognitive training program based on the n-back task. Twenty-six young women completed twenty-four training sessions across twelve weeks and they showed, on average, large cognitive improvements. High-resolution MRI scans were obtained before and after training. The computed longitudinal deformation maps were analyzed for answering three questions: (a) Are there differential brain structural changes in the training group as compared with a matched control group? (b) Are these changes related to performance differences in the training program? (c) Are standardized changes in a set of psychological factors (fluid and crystallized intelligence, working memory, and attention control) measured before and after training, related to structural changes in the brain? Results showed (a) greater structural changes for the training group in the temporal lobe, (b) a negative correlation between these changes and performance across training sessions (the greater the structural change, the lower the cognitive performance improvements), and (c) negligible effects regarding the psychological factors measured before and after training.