The Korean Repeatable Battery for the Assessment of Neuropsychological Status-Update : Psychiatric and Neurosurgery Patient Sample Validity

Effect of Chewing Hardness on Cognitive-Associated Brain Regions Activation

INTRODUCTION AND AIMS

Recent findings suggest a potential correlation between mastication and cognitive processes. However, the comprehensive investigation into the neurobiological mechanisms of masticatory control, such as the impact of chewing hardness, on cognitive function, remains incomplete. This study aims to investigate the impact of chewing hardness, as an aspect of masticatory control, on cognitive function by examining brain activation patterns during hard and soft chewing conditions.

METHODS

A total of 52 healthy young adults (average age of 21.81 years; 24 men and 28 women) underwent fMRI scanning, during which 27 individuals chewed soft and 25 individual chewed hard material. The functional magnetic resonance imaging (fMRI) was employed to elucidate the overlapping and distinct patterns of activated brain regions associated with soft- and hard-chewing conditions. Subsequently, correlations between these activated brain regions and neuropsychological measures were assessed.

RESULTS

Conjunction analysis revealed that both soft- and hard-chewing conditions stimulated brain regions directly associated with orofacial movement and spatial information processing. Two-sample t-test result indicated that the hard-chewing group had higher activation mostly in the caudate nucleus and frontal brain regions associated with cognitive function compared with the soft-chewing group. Furthermore, the activation strength of these brain regions positively correlated with neuropsychological measures.

CONCLUSION

The findings suggest that hard-chewing may be more effective than soft-chewing in stimulating cognition-associated brain regions, potentially enhancing cognitive processing.

CLINICAL RELEVANCE

Our study shows that hard-chewing activates brain regions linked to cognitive function more than soft-chewing. This suggests that harder chewing could be used as a simple, non-invasive method to enhance cognitive processing. Incorporating harder foods into the diet may offer a practical approach to support cognitive health and improve mental performance.

Effect of chewing hard material on boosting brain antioxidant levels and enhancing cognitive function

Introduction

Chewing has been reported to enhance cognitive function through the increase in cerebral blood flow. However, the mechanisms linking cerebral blood flow increase to metabolic changes in the brain affecting cognition remain unclear. We hypothesized that glutathione (GSH) plays a pivotal role in these mechanisms. Therefore, this study aimed to investigate changes in brain GSH levels following chewing and their association with cognitive function in healthy young adults.

Methods

A total of 52 university students were recruited, and the Korean version of the Repeatable Battery for the Assessment of Neuropsychological Status was used for the neurocognitive evaluations. Brain GSH levels following chewing gum or wood blocks were measured using MEscher-GArwood Point RESolved Spectroscopy (MEGA-PRESS) sequence, and their relevance to neurocognitive evaluation results was investigated.

Results

Chewing significantly increased brain GSH concentration, particularly in the wood-chewing group compared to the gum-chewing group, as observed in the anterior cingulate cortex. Furthermore, the rise in GSH concentration in the wood-chewing group was positively correlated with memory function.

Conclusion

Chewing moderately hard material elevates brain antioxidant levels such as GSH, potentially influencing cognitive function.

Risk Factors for Rapid Cognitive Decline in Amyloid-Negative Individuals Without Cognitive Impairment or With Early-Stage Cognitive Loss in Screening Tests

PURPOSE

Although rapid cognitive decline (RCD) is an important unfavorable prognostic factor, not much is known about it, especially in amyloid-negative individuals. The purpose of this study was to investigate risk factors for RCD in amyloid-negative individuals.

PATIENTS AND METHODS

We retrospectively enrolled 741 individuals who were either cognitively unimpaired or had early-stage cognitive ability loss and who underwent 18 F-florbetaben (FBB) (n = 402) or 18 F-flutemetamol (FMM) (n = 339) PET/CT. Based on visual and semiquantitative (SUV ratio [SUVR]-based) analysis, the following amyloid-negative groups were established: visual-negative FBB (n = 232), visual-negative FMM (n = 161), SUVR-negative FBB (n = 104), and SUVR-negative FMM (n = 101). Univariable and multivariable logistic regression analyses were performed for RCD using 5 SUVRs, 5 cortical thicknesses, and 5 neuropsychological domains and clinico-demographic factors.

RESULTS

In the amyloid-negative groups, a decline in language function was commonly identified as a significant risk factor for RCD ( P = 0.0044 in the visual-negative FBB group, P = 0.0487 in the visual-negative FMM group, P = 0.0031 in the SUVR-negative FBB group, and P = 0.0030 in the SUVR-negative FMM group). In addition, declines in frontal/executive function, frontal SUVR, and parietal SUVR; a longer duration of education; and mild cognitive decline in the amyloid-negative groups were also significant risk factors for RCD.

CONCLUSIONS

Even in amyloid-negative individuals without cognitive impairment or with early-stage cognitive ability loss, those with decreased language and frontal/executive functions on neuropsychological testing are at risk of progression to RCD.

Effect of Anti-Aging Standard Forest Healing Program With Multiple Visits to a Forest Facility on Cognition in Older Age Patients

Background and purpose

The anti-aging standard forest healing program (ASFHP), which uses forest therapy, was reported to be effective in improving psychological, physical, and cognitive functions. However, there are several challenges to directly visiting the forest. This study aimed to investigate the impact of multi-session ASFHP with forest visit on the mental and physical health of the older people with visits to forest facilities and compared them with those of the same program conducted indoors.

Methods

Individuals aged over 70 years with concerns about cognitive decline were recruited at dementia relief centers and divided into control and experimental groups. A total of 33 people were administered ASFHP under the supervision of a forest therapy instructor. The control group stayed indoors, while the experimental group visited a forest healing center and repeated the program 20 weeks.

Results

The multiple-session ASFHP positively affected cognitive impairment screening test (CIST) total scores (p=0.002), memory (p=0.014), Korean version of the Repeatable Battery for the Assessment of Neuropsychological Status total scores (p<0.001), immediate recall (p=0.001), visuospatial/construction (p<0.001), language (p<0.001), forest healing standard questionnaire total scores (p=0.002), and cognitive function (p=0.019), regardless of location. The forest visits during the ASFHP showed positive effects on orientation (p=0.035), delayed recall (p=0.042), emotional stability (p=0.032), physical activity (p=0.005), and health (p=0.022). The CIST scores of the memory domain were the strongest indicator of the multiple-session ASFHP effects.

Conclusions

The 20-week multi-session ASFHP with forest visit showed effects on cognitive improvement and physical and emotional stability compared to indoor education.

Effects of Exercise on Urinary AD7c-NTP (Alzheimer-Associated Neuronal Thread Protein) Levels and Cognitive Function Among Active Korean Elderly: A Randomized Controlled Trial

Background

Alzheimer-associated neuronal thread protein (AD7c-NTP) has been demonstrated to have high diagnostic accuracy in differentiating Alzheimer's disease (AD) patients from healthy individuals. However, it is yet unclear whether exercise can lower the level of AD7c-NTP in urine among active Korean elderly.

Objective

To assess the effect of exercise on AD7c-ntp levels in urine and cognitive function among active Korean elderly.

Methods

In total, 40 Korean elderly (≥65 years) were divided into Active Control group (CG, n = 10), Aerobic exercise group (AG, n = 18), and combined Resistance/Aerobic exercise group (RAG, n = 12). A total of 12 weeks of exercise intervention was implemented. At week 0 and 12, cognitive performance (Korean Mini-Mental State Examination, Korean-Color Word Stroop test), grip strength, and body composition (muscle mass and body fat percentage) were measured. Also, a morning urine sample was obtained from each subject. The level of AD7c-NTP was measured using competitive enzyme-linked immunosorbent assay (ELISA).

Results

After 12 weeks of exercise intervention, there was a significant difference of AD7c-NTP levels between RAG and CG (p = 0.026), AG and CG (p = 0.032), respectively. Furthermore, the AD7c-NTP levels in urine showed negative correlation with K-MMSE scores (r = -0.390, p = 0.013) and grip strength (r = -0.376, p = 0.017), among all participants after exercise intervention.

Conclusions

This is the first study to investigate urine biomarker through exercise intervention. In future stuides, participants who have low cognitive function and low activity levels need to be recruited to observe more significant 'Exercise' effect.

Efficacy of a Mobile-Based Multidomain Intervention to Improve Cognitive Function and Health-Related Outcomes Among Older Korean Adults with Subjective Cognitive Decline

BACKGROUND

Subjective cognitive decline (SCD) is a self-reported experience of declining cognitive function showing normal performance in cognitive assessments, which is a known risk factor for dementia. Recent studies highlight the importance of nonpharmacological multidomain interventions that can target multiple risk factors of dementia in older adults.

OBJECTIVE

This study investigated the efficacy of the Silvia program, a mobile-based multidomain intervention, to improve cognitive function and health-related outcomes of older adults with SCD. We compare its effects to a conventional paper-based multidomain program on various health indicators related to risk factors of dementia.

METHODS

This prospective randomized controlled trial involved 77 older adults with SCD recruited from the Dementia Prevention and Management Center in Gwangju, South Korea during May to October 2022. Participants were randomly assigned to either the mobile- or paper-based group. Interventions were administered for 12 weeks, where pre- and post-assessments were conducted.

RESULTS

The K-RBANS total score did not show significant differences between groups. The mobile group showed better improvement in K-PRMQ scores and PSS scores than the paper group. Differences within groups showed that mobile-based interventions significantly improved K-PRMQ, STAI-X-1, PSS, and EQ-5D-5 L scores, while paper-based interventions significantly improved PSS, and EQ-5D-5 L scores. Patient adherence rate was 76.6%.

CONCLUSION

Overall, the Silvia program was effective for improving self-reported memory failures, stress, anxiety, and health-related quality of life in older adults with SCD. However, longer periods of administration for more than 12 weeks may be needed to achieve significant improvements in cognitive function by objective measures.

A Study on Verification of Equivalence and Effectiveness of Non-Pharmacologic Dementia Prevention and Early Detection Contents : Non-Randomly Equivalent Design

Objective

The aim of this study was to verify the equivalence and effectiveness of the tablet-administered Korean Repeatable Battery for the Assessment of Neuropsychological Status (K-RBANS) for the prevention and early detection of dementia.

Methods

Data from 88 psychiatry and neurology patient samples were examined to evaluate the equivalence between tablet and paper administrations of the K-RBANS using a non-randomly equivalent group design. We calculated the prediction scores of the tablet-administered K-RBANS based on demographics and covariate-test scores for focal tests using norm samples and tested format effects. In addition, we compared the receiver operating characteristic curves to confirm the effectiveness of the K-RBANS for preventing and detecting dementia.

Results

In the analysis of raw scores, line orientation showed a significant difference (t=-2.94, p<0.001), and subtests showed small to large effect sizes (0.04–0.86) between paper- and tablet-administered K-RBANS. To investigate the format effect, we compared the predicted scaled scores of the tablet sample to the scaled scores of the norm sample. Consequently, a small effect size (d≤0.20) was observed in most of the subtests, except word list and story recall, which showed a medium effect size (d=0.21), while picture naming and subtests of delayed memory showed significant differences in the one-sample t-test. In addition, the area under the curve of the total scale index (TSI) (0.827; 95% confidence interval, 0.738–0.916) was higher than that of the five indices, ranging from 0.688 to 0.820. The sensitivity and specificity of TSI were 80% and 76%, respectively.

Conclusion

The overall results of this study suggest that the tablet-administered K-RBANS showed significant equivalence to the norm sample, although some subtests showed format effects, and it may be used as a valid tool for the brief screening of patients with neuropsychological disorders in Korea.