Alzheimer’s disease and related dementia are associated with significant societal costs and economic burdens and have been associated with decreases in cortical gray matter volume. This pilot cross-sectional study investigates the relationship between total fiber concentration in diet, total calorie density per diet, and regional GMV in a cohort of 190 patients aged 20 to 79 years, utilizing data from the 2015 National Health Interview Survey Supplement and T1-weighted magnetic resonance imaging (MRI) collected at the McCausland Center for Brain Imaging. Gray matter volumes were quantified using the CAT12 voxel-based morphometry toolbox and statistical correlations between GMV and dietary measures were assessed using Spearman’s rank order correlation coefficient. Our exploratory analysis revealed a significant positive correlation between dietary fiber consumption and GMV in 16 different areas, including the right Hippocampus (r (190) = 0.196, p = 0.003) and left Hippocampus (r (190) = 0.135, p = 0.032), when controlling for age and race of participants. Our analyses revealed significantly negative correlations between total calorie density per diet and localized GMV in 3 different brain areas, including the right Precentral Gyrus (r (190) = -0.15, p = 0.039) and right Thalamic Pulvinar (r (190) = -0.155, p = 0.033), when controlling for participant race. Together, our initial findings suggest that dietary fiber and calorie density are associated with GMV even after controlling for relevant demographic variables. If replicated, these findings could have important implications for dietary advice given to individuals at risk for developing MCI or more serious forms of dementia.

Abstract In stroke aphasia, lesion volume is typically associated with aphasia severity. Although this relationship is likely present throughout recovery, different factors may affect lesion volume and behaviour early into recovery (acute) and in the later stages of recovery (chronic). Therefore, studies typically separate patients into two groups (acute/chronic), and this is often accompanied with arguments for and against using data from acute stroke patients over chronic. However, no comprehensive studies have provided strong evidence of whether the lesion–behaviour relationship early in recovery is comparable to later in the recovery trajectory. To that end, we investigated two aims: (i) whether lesion data from acute and chronic patients yield similar results in region-based lesion-symptom mapping analyses and (ii) if models based on one timepoint accurately predict the other. Lesions and aphasia severity scores from acute (N = 63) and chronic (N = 109) stroke survivors with aphasia were entered into separate univariate region-based lesion-symptom mapping analyses. A support vector regression model was trained on lesion data from either the acute or chronic data set to give an estimate of aphasia severity. Four model-based analyses were conducted: trained on acute/chronic using leave-one-out, tested on left-out behaviour or trained on acute/chronic to predict the other timepoint. Region-based lesion-symptom mapping analyses identified similar but not identical regions in both timepoints. All four models revealed positive correlations between actual and predicted Western Aphasia Battery-Revised aphasia-quotient scores. Lesion-to-behaviour predictions were almost equivalent when comparing within versus across stroke stage, despite differing lesion size/locations and distributions of aphasia severity between stroke timepoints. This suggests that research investigating the brain–behaviour relationship including subsets of patients from only one timepoint may also be applicable at other timepoints, although it is important to note that these comparable findings may only be seen using broad measures such as aphasia severity, rather than those aimed at identifying more specific deficits. Subtle differences found between timepoints may also be useful in understanding the nature of lesion volume and aphasia severity over time. Stronger correlations found when predicting acute behaviour (e.g. predicting acute: r = 0.6888, P < 0.001, predicting chronic r = 0.5014, P < 0.001) suggest that the acute lesion/perfusion patterns more accurately capture the critical changes in underlying vascular territories. Differences in critical brain regions between timepoints may shed light on recovery patterns. Future studies could focus on a longitudinal design to compare acute and chronic patients in a more controlled manner.

BACKGROUND:Substantial effort has been undertaken to improve the recruitment and retention of participants in stroke trials. African Americans are disproportionately under-represented in stroke clinical trials as well as clinical trials for other chronic disease conditions. To circumvent barriers to recruitment, clinical trial recruitment strategies used to recruit African Americans have focused on different aspects of community engagement.PURPOSE:This study examined a community-engaged, multi-phased tailored approach to recruiting African Americans with stroke. The recruitment approach described was designed to support the Community Based Intervention under Nurse Guidance after Stroke (CINGS) trial, part of the Wide Spectrum Investigation of Stroke Outcome Disparities on Multiple Levels (WISSDOM) Center established to explore stroke disparities.METHODS:A multiple-phased recruitment approach was undertaken and involved a recruitment planning phase and a recruitment phase. The recruitment planning phase involved the use of focus groups designed to explore barriers and facilitators of stroke recovery. The active recruitment phase included multiple strategies with ongoing evaluation.RESULTS:Information gained from focus groups offered insights into strategies critical to recruiting African Americans with stroke for behavioral research during the early recovery period. Strategies to enhance the identification of and recruitment of potential participants included use of: a) a hospital system stroke database, b) system-wide friendly visits/warm handoff approaches, c) electronic health record, d) associated external sites and e) protocol adjustments.CONCLUSIONS:Developing tailored approaches to curtail barriers to research participation is critical for increasing the probability of reaching African American study participant recruitment and retention goals. Research teams may require training in community-engagement research strategies essential for obtaining achieving target recruitment goals.

Background: Prefrontal abnormalities in schizophrenia have consistently emerged from resting state and cognitive neuroimaging studies. However, these correlative findings require causal verification via combined imaging/stimulation approaches. To date, no interleaved transcranial magnetic stimulation and functional magnetic resonance imaging study (TMS fMRI) has probed putative prefrontal cortex abnormalities in schizophrenia. Objective: /Hypothesis: We hypothesized that subjects with schizophrenia would show significant hyperexcitability at the site of stimulation (BA9) and decreased interhemispheric functional connectivity. Methods: We enrolled 19 unmedicated subjects with schizophrenia and 22 controls. All subjects underwent brain imaging using a 3T MRI scanner with a SENSE coil. They also underwent a single TMS fMRI session involving motor threshold (rMT) determination, structural imaging, and a parametric TMS fMRI protocol with 10 Hz triplet pulses at 0, 80, 100 and 120% rMT. Scanning involved a surface MR coil optimized for bilateral prefrontal cortex image acquisition. Results: Of the original 41 enrolled subjects, 8 subjects with schizophrenia and 11 controls met full criteria for final data analyses. At equal TMS intensity, subjects with schizophrenia showed hyperexcitability in left BA9 (p = 0.0157; max z-score = 4.7) and neighboring BA46 (p = 0.019; max z-score = 4.47). Controls showed more contralateral functional connectivity between left BA9 and right BA9 through increased activation in right BA9 (p = 0.02; max z-score = 3.4). GM density in subjects with schizophrenia positively correlated with normalized prefrontal to motor cortex ratio of the corresponding distance from skull to cortex ratio (S-BA9/S-MC) (r = 0.83, p = 0.004). Conclusions: Subjects with schizophrenia showed hyperexcitability in left BA9 and impaired interhemispheric functional connectivity compared to controls. Interleaved TMS fMRI is a promising tool to investigate prefrontal dysfunction in schizophrenia.

Left-hemisphere brain damage commonly affects patients' abilities to produce and comprehend syntactic structures, a condition typically referred to as “agrammatism.” The neural correlates of agrammatism remain disputed in the literature, and distributed areas have been implicated as important predictors of performance, for example, Broca's area, anterior temporal areas, and temporo-parietal areas. We examined the association between damage to specific language-related ROIs and impaired syntactic processing in acute aphasia. We hypothesized that damage to the posterior middle temporal gyrus, and not Broca's area, would predict syntactic processing abilities. One hundred four individuals with acute aphasia (<20 days poststroke) were included in the study. Structural MRI scans were obtained, and all participants completed a 45-item sentence–picture matching task. We performed an ROI-based stepwise regression analyses to examine the relation between cortical brain damage and impaired comprehension of canonical and noncanonical sentences. Damage to the posterior middle temporal gyrus was the strongest predictor for overall task performance and performance on noncanonical sentences. Damage to the angular gyrus was the strongest predictor for performance on canonical sentences, and damage to the posterior superior temporal gyrus predicted noncanonical scores when performance on canonical sentences was included as a cofactor. Overall, our models showed that damage to temporo-parietal and posterior temporal areas was associated with impaired syntactic comprehension. Our results indicate that the temporo-parietal area is crucially implicated in complex syntactic processing, whereas the role of Broca's area may be complementary.

Title: The Superior Precentral Gyrus of the Insula does not appear to be 1 functionally specialized for articulation 2 3 Abbreviated title: SPGI not specialized for articulation 4 5 6 Evelina Fedorenko, Paul Fillmore, Kimberly Smith, Leo Bonilha and Julius 7 Fridriksson 8 9 Massachusetts General Hospital, University of South Carolina, Medical University of 10 South Carolina 11 12 Corresponding author: Evelina Fedorenko, evelina.fedorenko@mgh.harvard.edu 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 Acknowledgments: 39 We thank Peter Graff and Morris Alper for help in the construction of pseudowords, 40 Taylor Hanayik for help with recording the materials, Nina Dronkers for providing the 41 SPGI mask, Chris Rorden, Alfonso Nieto-Castañon and Sheeba Anteraper for help with 42 some preprocessing steps. For comments on this work, we thank the audience at the 43 Neurobiology of Language conference (2013, San Diego) and Nancy Kanwisher. This 44 work was supported by a grant (DC009571) from the NIDCD to JF and a grant 45 (HD057522) from the NICHD to EF. 46 Articles in PresS. J Neurophysiol (January 28, 2015). doi:10.1152/jn.00214.2014