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Background: Cosmos caudatus (CC) is traditional Asian vegetable, commonly consumed among the Southeast Asian population. It has been reported to be high in flavonoids and might potentially improve brain activity among older adults with mild cognitive impairment (MCI). The effect of CC in brain activation improvement using neuroimaging is yet to be discovered. Purpose: To investigate the effects of CC supplement on brain activity using functional magnetic resonance imaging (fMRI) among older adults with MCI. Study type: Prospective, randomized, double‐blind, placebo‐controlled trial. Population/subjects: Twenty older adults with mild cognitive impairment (60–75 years old), 14 of them (70%) were female subjects. Field strength/sequence: A 3.0‐T, T1‐weighted anatomical images, T2*‐weighted imaging data, A single shot, gradient echo‐echo planar imaging (EPI) sequence. Assessment: All subjects were asked to consume two 500 mg capsules of either CC supplement or placebo (maltodextrin) daily for 12 weeks. Cognitive function was measured using validated neuropsychological tests (i.e. Mini‐mental State Examination and Digit Span) and task‐based fMRI (N‐back and Stroop Color Word Test) at baseline and 12th week. Brodmann's area 9, 46 and anterior cingulate cortex were selected as the regions of interest to define dorsolateral prefrontal cortex (DLPFC) in fMRI analysis. Statistical tests: Normality test was performed with the Shapiro–Wilk test. Two‐way repeated ANOVA determined the intervention effects of the CC supplementation on brain activity after adjustments for covariates. Significance level at P < 0.05 for independent‐t test and Chi square test; adjusted P < 0.0042 for two‐way repeated ANOVA after Bonferroni correction. Results: Findings showed significant improvements in digit span (partial η2 = 0.559), increment in right DLPFC activation while performing 1‐back task (partial η2 = 0.586) and left DLPFC activation while performing Stroop Color Word Test (SCWT) (congruent) task (partial η2 = 0.432) at 12th week of CC supplementation. Conclusion: CC supplementation might have the ability to improve DLPFC activation, potentially leading to improved working memory among older adults with MCI after 12 weeks of administration. Level of evidence: 1 Technical efficacy: Stage 4 [ABSTRACT FROM AUTHOR]

Background: The auditory and prefrontal cortex supports auditory working memory processing. Many neuroimaging studies have shown hemispheric lateralization of auditory working memory brain regions in the presence of background noise, but few studies have focused on the lateralization of these regions during stochastic resonance.Purpose: To investigate the effects of stochastic resonance on lateralization of auditory working memory regions, and also to examine the brain-behavior relationship during stochastic resonance.Study Type: Cross-sectional.Population/subjects: Forty healthy young adults (18-24 years old).Field Strength/sequence: 3.0T, T1 , and T2 *-weighted imaging.Assessment: The auditory working memory performance was assessed using a backward recall task. Functional magnetic resonance imaging (fMRI) was used to measure brain activity during task performance. Functional MRI data were analyzed using SPM12 and WFU PickAtlas.Statistical Tests: One-way independent analyses of variance (ANOVA) were conducted on the behavioral and functional data to examine the main effect of noise level on performance (P < 0.01) and brain activity (P < 0.0042). Hemispheric lateralization was determined by calculating the laterality index. A paired samples t-test was performed to compare brain activity between hemispheres (P < 0.05). Pearson's correlation analysis and simple linear regression (P < 0.0042) were used to examine the relationship between brain activity and behavioral performance.Results: Performance was significantly enhanced during the 50 and 55 dB sound pressure level (SPL) conditions via the stochastic resonance mechanism [F(1,195) = 49.17, P < 0.001]. Activity of the right superior frontal gyrus in the 55 dB SPL condition was significantly positively correlated with performance (R2 = 0.681, P < 0.001).Data Conclusion: Our findings demonstrate changes in the lateralization of auditory working memory regions during stochastic resonance and suggest that the right superior frontal gyrus may be a strategic structure involved in the enhancement of auditory working memory performance.Level Of Evidence: 2 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2020;51:1821-1828. [ABSTRACT FROM AUTHOR]

Background: Working memory and cognitive flexibility are supported by the dorsolateral prefrontal cortex (DLPFC). Aging adults from low-income households are individuals with a high risk of cognitive decline who incorporate ulam in their daily diet.Purpose: To examine relationship between ulam consumption and the working memory and cognitive flexibility among aging adults from low-income households who are more susceptible to cognitive decline.Study Type: Cross-sectional.Population/subjects: Thirty-two aging adults (45-75 years old).Field Strength/sequence: Task-based fMRI, 3.0T, T1 -weighted anatomical images, T2 *-weighted imaging data.Assessment: The dietary and ulam consumption were assessed using the respective validated Dietary History and semiquantitative Food Frequency questionnaires. Working memory and cognitive flexibility were evaluated by using neuropsychological batteries (ie, mini-mental state examination [MMSE], Digit Span, and Rey auditory verbal learning test [RAVLT]) and task-based fMRI (N-back and Stroop Color Word Test [SCWT]). Brodmann's areas 9 and 46 were the regions of interest (ROIs) of DLPFC activation.Statistical Tests: Multiple linear regression used to understand the relationship between ulam consumption and the working memory and cognitive flexibility, while analysis of covariance (ANCOVA) was used to compare the difference of working memory and cognitive flexibility among four percentiles of ulam consumption, after age, gender, and education years adjustments. Significance was decided by two-sided, P < 0.0042 and P < 0.05.Results: The multiple linear regression revealed that ulam consumption was positively associated with the Digit Span (R2 = 0.51, β = 0.702, P < 0.001), right DLPFC activation (1-back) (R2 = 0.34, β = 0.591, P = 0.001), left DLPFC activation (SCWT-1) (R2 = 0.33, β = 0.553, P = 0.002), and left DLPFC activation (SCWT-2) (R2 = 0.34, β = 0.497, P = 0.004). The ulam consumption at the 75th and 100th percentile from the ANCOVA analysis had shown a better working memory and cognitive flexibility as compared with those of the 25th and 50th percentiles (P < 0.05).Data Conclusion: This study found that high ulam consumption was related to a high intensity of brain activation in DLPFC; however, the elucidation of the neuroprotective properties of ulam have yet to be established from clinical trial studies.Level Of Evidence: 2 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2020;51:1142-1153. [ABSTRACT FROM AUTHOR]

Background: Dorsolateral prefrontal cortex (DLPFC) is a key node in the cognitive control network that supports working memory. DLPFC dysfunction is related to cognitive impairment. It has been suggested that dietary components and high-density lipoprotein cholesterol (HDL-C) play a vital role in brain health and cognitive function. Purpose: This study aimed to investigate the relationships between dietary nutrient intake and lipid levels with functional MRI (fMRI) brain activation in DLPFC among older adults with mild cognitive impairment. Participants and methods: A total of 15 community-dwelling older adults with mild cognitive impairment, aged ≥60 years, participated in this cross-sectional study at selected senior citizen clubs in Klang Valley, Malaysia. The 7-day recall Diet History Questionnaire was used to assess participants’ dietary nutrient intake. Fasting blood samples were also collected for lipid profile assessment. All participants performed N-back (0- and 1-back) working memory tasks during fMRI scanning. DLPFC (Brodmann’s areas 9 and 46, and inferior, middle, and superior frontal gyrus) was identified as a region of interest for analysis. Results: Positive associations were observed between dietary intake of energy, protein, cholesterol, vitamins B6 and B12, potassium, iron, phosphorus, magnesium, and HDL-C with DLPFC activation (P<0.05). Multivariate analysis showed that vitamin B6 intake, β=0.505, t (14)=3.29, P=0.023, and Digit Symbol score, β=0.413, t (14)=2.89, P=0.045; R2=0.748, were positively related to DLPFC activation. Conclusion: Increased vitamin B6 intake and cognitive processing speed were related to greater activation in the DLPFC region, which was responsible for working memory, executive function, attention, planning, and decision making. Further studies are needed to elucidate the mechanisms underlying the association. [ABSTRACT FROM AUTHOR]

Background: In spite of extensive research conducted to study how human brain works, little is known about a special function of the brain that stores and manipulates information-the working memory-and how noise influences this special ability. In this study, Functional magnetic resonance imaging (fMRI) was used to investigate brain responses to arithmetic problems solved in noisy and quiet backgrounds. Methods: Eighteen healthy young males performed simple arithmetic operations of addition and subtraction with in-quiet and in-noise backgrounds. The MATLAB-based Statistical Parametric Mapping (SPM8) was implemented on the fMRI datasets to generate and analyse the activated brain regions. Results: Group results showed that addition and subtraction operations evoked extended activation in the left inferior parietal lobe, left precentral gyrus, left superior parietal lobe, left supramarginal gyrus, and left middle temporal gyrus. This supported the hypothesis that the human brain relatively activates its left hemisphere more compared with the right hemisphere when solving arithmetic problems. The insula, middle cingulate cortex, and middle frontal gyrus, however, showed more extended right hemispheric activation, potentially due to the involvement of attention, executive processes, and working memory. For addition operations, there was extensive left hemispheric activation in the superior temporal gyrus, inferior frontal gyrus, and thalamus. In contrast, subtraction tasks evoked a greater activation of similar brain structures in the right hemisphere. For both addition and subtraction operations, the total number of activated voxels was higher for in-noise than in-quiet conditions. Conclusion: These findings suggest that when arithmetic operations were delivered auditorily, the auditory, attention, and working memory functions were required to accomplish the executive processing of the mathematical calculation. The respective brain activation patterns appear to be modulated by the noisy background condition. [ABSTRACT FROM AUTHOR]