Yuka Kotozaki

Brain Training Game Improves Executive Functions and Processing Speed in the Elderly: A Randomized Controlled Trial

Background The beneficial effects of brain training games are expected to transfer to other cognitive functions, but these beneficial effects are poorly understood. Here we investigate the impact of the brain training game (Brain Age) on cognitive functions in the elderly. Methods and Results Thirty-two elderly volunteers were recruited through an advertisement in the local newspaper and randomly assigned to either of two game groups (Brain Age, Tetris). This study was completed by 14 of the 16 members in the Brain Age group and 14 of the 16 members in the Tetris group. To maximize the benefit of the interventions, all participants were non-gamers who reported playing less than one hour of video games per week over the past 2 years. Participants in both the Brain Age and the Tetris groups played their game for about 15 minutes per day, at least 5 days per week, for 4 weeks. Each group played for a total of about 20 days. Measures of the cognitive functions were conducted before and after training. Measures of the cognitive functions fell into four categories (global cognitive status, executive functions, attention, and processing speed). Results showed that the effects of the brain training game were transferred to executive functions and to processing speed. However, the brain training game showed no transfer effect on any global cognitive status nor attention. Conclusions Our results showed that playing Brain Age for 4 weeks could lead to improve cognitive functions (executive functions and processing speed) in the elderly. This result indicated that there is a possibility which the elderly could improve executive functions and processing speed in short term training. The results need replication in large samples. Long-term effects and relevance for every-day functioning remain uncertain as yet. Trial Registration UMIN Clinical Trial Registry 000002825

Brain Training Game Boosts Executive Functions, Working Memory and Processing Speed in the Young Adults: A Randomized Controlled Trial

Background Do brain training games work? The beneficial effects of brain training games are expected to transfer to other cognitive functions. Yet in all honesty, beneficial transfer effects of the commercial brain training games in young adults have little scientific basis. Here we investigated the impact of the brain training game (Brain Age) on a wide range of cognitive functions in young adults. Methods We conducted a double-blind (de facto masking) randomized controlled trial using a popular brain training game (Brain Age) and a popular puzzle game (Tetris). Thirty-two volunteers were recruited through an advertisement in the local newspaper and randomly assigned to either of two game groups (Brain Age, Tetris). Participants in both the Brain Age and the Tetris groups played their game for about 15 minutes per day, at least 5 days per week, for 4 weeks. Measures of the cognitive functions were conducted before and after training. Measures of the cognitive functions fell into eight categories (fluid intelligence, executive function, working memory, short-term memory, attention, processing speed, visual ability, and reading ability). Results and Discussion Our results showed that commercial brain training game improves executive functions, working memory, and processing speed in young adults. Moreover, the popular puzzle game can engender improvement attention and visuo-spatial ability compared to playing the brain training game. The present study showed the scientific evidence which the brain training game had the beneficial effects on cognitive functions (executive functions, working memory and processing speed) in the healthy young adults. Conclusions Our results do not indicate that everyone should play brain training games. However, the commercial brain training game might be a simple and convenient means to improve some cognitive functions. We believe that our findings are highly relevant to applications in educational and clinical fields. Trial Registration UMIN Clinical Trial Registry 000005618.

Effects of working memory training on functional connectivity and cerebral blood flow during rest

Working memory (WM) training (WMT) alters the task-related brain activity and structure of the external attention system (EAS). We investigated whether WMT also alters resting-state brain mechanisms, which are assumed to reflect intrinsic brain activity and connectivity. Our study subjects were subjected to a 4-week WMT program and brain scans before and after the intervention for determining changes of functional connectivity and regional cerebral blood flow during rest (resting-FC/resting-rCBF). Compared with no-intervention, WMT (a) increased resting-FC between the medial prefrontal cortex (mPFC) and precuneus, which are key nodes of the default mode network (DMN), (b) decreased resting-FC between mPFC and the right posterior parietal cortex/right lateral prefrontal cortex (LPFC), which are key nodes of the EAS, and (c) increased resting-rCBF in the right LPFC. However, the training-related decreases in resting-FC between the key DMN node and the nodes of EAS were only observed when the whole brain signal was regressed out in individual analyses, and these changes were not observed when the whole brain signal was not regressed out in individual analyses. Further analyses indicated that these differences may be mediated by a weak but a widespread increase in resting-FC between the nodes of EAS and activity of multiple bilateral areas across the brain. These results showed that WMT induces plasticity in neural mechanisms involving DMN and the EAS during rest and indicated that intrinsic brain activity and connectivity can be affected by cognitive training.

Brain structural changes as vulnerability factors and acquired signs of post-earthquake stress.

Many survivors of severe disasters, even those without posttraumatic stress disorder (PTSD), need psychological support. To understand the pathogenesis of PTSD symptoms and prevent the development of PTSD, the critical issue is to distinguish neurological abnormalities as vulnerability factors from acquired signs of PTSD symptoms in the early stage of adaptation to the trauma in the normal population. The neurological underpinnings of PTSD have been well characterized, but the causal relationships with the traumatic event are still unclear. We examined 42 non-PTSD subjects to find brain morphometric changes related to the severity of PTSD symptoms in a longitudinal magnetic resonance imaging study extending through the Great East Japan Earthquake. We found that regional grey matter volume (rGMV) in the right ventral anterior cingulate cortex (ACC) before the earthquake, and decreased rGMV in the left orbitofrontal cortex (OFC) through the earthquake were negatively associated with PTSD symptoms. Our results indicate that subjects with smaller GMV in the ACC before the earthquake, and subjects with decreased GMV in the OFC through the earthquake were likely to have PTSD symptoms. As the ACC is involved in processing of fear and anxiety, our results indicate that these processing are related to vulnerability for PTSD symptoms. In addition, decreased OFC volume was induced by failing to extinct conditioned fear soon after the traumatic event. These findings provide a better understanding of posttraumatic responses in early stage of adaptation to the trauma and may contribute to the development of effective methods to prevent PTSD.

Correlation among body height, intelligence, and brain gray matter volume in healthy children

A significant positive correlation between height and intelligence has been demonstrated in children. Additionally, intelligence has been associated with the volume of gray matter in the brains of children. Based on these correlations, we analyzed the correlation among height, full-scale intelligence quotient (IQ) and gray matter volume applying voxel-based morphometry using data from the brain magnetic resonance images of 160 healthy children aged 5-18 years of age. As a result, body height was significantly positively correlated with brain gray matter volume. Additionally, the regional gray matter volume of several regions such as the bilateral prefrontal cortices, temporoparietal region, and cerebellum was significantly positively correlated with body height and that the gray matter volume of several of these regions was also significantly positively correlated with full-scale intelligence quotient (IQ) scores after adjusting for age, sex, and socioeconomic status. Our results demonstrate that gray and white matter volume may mediate the correlation between body height and intelligence in healthy children. Additionally, the correlations among gray and white matter volume, height, and intelligence may be at least partially explained by the effect of insulin-like growth factor-1 and growth hormones. Given the importance of the effect of environmental factors, especially nutrition, on height, IQ, and gray matter volume, the present results stress the importance of nutrition during childhood for the healthy maturation of body and brain.

Sleep duration during weekdays affects hippocampal gray matter volume in healthy children.

Sleep is essential for living beings, and sleep loss has been shown to affect hippocampal structure and function in rats by inhibiting cell proliferation and neurogenesis in this region of the brain. We aimed to analyze the correlation between sleep duration and the hippocampal volume using brain magnetic resonance images of 290 healthy children aged 5-18 years. We examined the volume of gray matter, white matter, and the cerebrospinal fluid (CSF) space in the brain using a fully automated and established neuroimaging technique, voxel-based morphometry, which enabled global analysis of brain structure without bias towards any specific brain region while permitting the identification of potential differences or abnormalities in brain structures. We found that the regional gray matter volume of the bilateral hippocampal body was significantly positively correlated with sleep duration during weekdays after adjusting for age, sex, and intracranial volume. Our results indicated that sleep duration affects the hippocampal regional gray matter volume of healthy children. These findings advance our understanding of the importance of sleep habits in the daily lives of healthy children.

Resting state functional connectivity associated with trait emotional intelligence

Previous neuroimaging studies have suggested that trait emotional intelligence (TEI) is associated with components of the neural network involved in social cognition (SCN) and somatic marker circuitry (SMC). Our study is the first to investigate the association of TEI with resting-state functional connectivity (RSFC) between the key nodes of SCN and SMC [medial prefromtal cortex (mPFC) and bilateral anterior insula (AI), respectively] and other brain regions. We found that (a) the intrapersonal factor of TEI was negatively correlated with RSFC between mPFC and the anterior part of the right dorsolateral prefrontal cortex (DLPFC), (b) the TEI interpersonal factor score was positively correlated with RSFC between mPFC and the lingual gyrus, and (c) total TEI was positively correlated with RSFC between mPFC and the precuneus as well as (d) between the left AI and the middle part of the right DLPFC. Taken together with previous study findings, our findings can be comprehensively understood as neural mechanisms of SCN and SMC components are associated with TEI. In particular, the fluent interaction between SCNs two key nodes (mPFC and precuneus/PCC) [as well as between DMNs two key nodes] is suggested to be crucial for total TEI. Our study also indicated that (a) a clear functional separation between the two key nodes of the two major intrinsic networks, DMN and the task-positive network (mPFC and DLPFC), is important for higher intrapersonal TEI, (b) brain interactions involving vision-related areas (lingual gyrus) and the key node of SCN (mPFC) are important for interpersonal TEI, and (c) control of DLPFC over the key node of SMC (AI) is important for total TEI.

Linear and Curvilinear Correlations of Brain White Matter Volume, Fractional Anisotropy, and Mean Diffusivity with Age Using Voxel-Based and Region- Of-Interest Analyses in 246 Healthy Children

In this study, we examined linear and curvilinear correlations of fractional anisotropy (FA), mean diffusivity (MD), and white matter volume with age by using brain structural and diffusion‐tensor magnetic resonance imaging (MRI) in a large number of healthy children and voxel‐based morphometry (VBM) and region‐of‐interest (ROI) analyses. We collected data by brain structural MRI in 246 healthy children, aged 5–18 years. FA and MD images were normalized using the normalization parameter of the corresponding structural MRI. Next, we analyzed the correlations between FA and age and between MD and age by estimating linear and logarithmic functions. We also analyzed the correlation between white matter volume and age by linear, quadratic, and cubic functions. Correlations between FA and age and between MD and age showed exponential trajectories in most ROIs in boys and girls, except for several fibers, such as the corpus callosum connecting the bilateral rectal gyri in boys. The correlation between white matter volume and age showed significant positive linear trajectories in most ROIs in boys and girls, except for a few fibers, such as the bilateral uncinate fasciculus. Additionally, maturational rates differed among major fibers, and in girls, the left superior longitudinal fasciculus, which connects the frontal and temporal lobes, showed a slower rate of maturation than other fibers. Our results may help to clarify the mechanisms of normal brain maturation from the viewpoint of brain white matter. Hum Brain Mapp, 2013.

Anatomical correlates of quality of life: Evidence from voxel-based morphometry

Quality of life (QOL) has been defined in many ways, and these definitions usually emphasize happiness and satisfaction with life. Health‐related problems are known to cause lower QOL. However, the neural mechanisms underlying individual differences in QOL measured by questionnaire (QOLMQ) in young healthy subjects are unknown. QOL is essential to our well‐being, and investigation of the neural mechanisms underlying QOL in uncompromised subjects is obviously of great scientific and social interest. We used voxel‐based morphometry to investigate the association between regional gray matter volume (rGMV) and QOLMQ across the brain in healthy young adults (age, 21.4 ± 1.8 years) men (n = 88) and women (n = 68) in humans. We found significant negative relationships between QOLMQ and rGMV in a region in the left rostrolateral prefrontal cortex and regions in the dorsal part of the anterior cingulate gyrus and contingent cingulate regions. These findings show that structural variations in regions associated with processing of negative emotions such as fear and anger as well as those associated with evaluation of internally generated information are associated with QOLMQ. These findings suggest that these processes might be related to QOLMQ in healthy young adults. Hum Brain Mapp 35:1834–1846, 2014.

The Impact of Television Viewing on Brain Structures: Cross-Sectional and Longitudinal Analyses

Television (TV) viewing is known to affect childrens verbal abilities and other physical, cognitive, and emotional development in psychological studies. However, the brain structural development associated with TV viewing has never been investigated. Here we examined cross-sectional correlations between the duration of TV viewing and regional gray/white matter volume (rGMV/rWMV) among 133 boys and 143 girls as well as correlations between the duration of TV viewing and longitudinal changes that occurred a few years later among 111 boys and 105 girls. After correcting for confounding factors, we found positive effects of TV viewing on rGMV of the frontopolar and medial prefrontal areas in cross-sectional and longitudinal analyses, positive effects of TV viewing on rGMV/rWMV of areas of the visual cortex in cross-sectional analyses, and positive effects of TV viewing on rGMV of the hypothalamus/septum and sensorimotor areas in longitudinal analyses. We also confirmed negative effects of TV viewing on verbal intelligence quotient (IQ) in cross-sectional and longitudinal analyses. These anatomical correlates may be linked to previously known effects of TV viewing on verbal competence, aggression, and physical activity. In particular, the present results showed effects of TV viewing on the frontopolar area of the brain, which has been associated with intellectual abilities.