bluuebunny/crossref_metadata_2025_split huggingface dataset:
86 Dementia Caregiver Burden associated with COVID-19 quarantine: A South American Cohort Study
Authors: Arruabarrena Micaela María , Fernandez Rodrigo , Canyazo Carlos Alberto Martinez , Corvalan Nicolas , Keller Greta , Carello Agostina , Sevlever Gustavo Emilio , Allegri Ricardo Francisco , Crivelli Lucía 
Published: December 2023

Objective:The objective of this study is to explore the impact on the mental health of caregivers of people with dementia during the period of mandatory preventive social isolation (ASPO) and to study which of these factors were predictors of caregiver overload.Participants and Methods:During the first 3 months of the ASPO (June 2020 to september 2020). A sample of 112 caregivers (75.89% female; age 58.65 ± 14. 30) of patients with dementia from a Memory Center answered, remotely (online or telephone) a survey with the following questionnaires: the Zarit Caregiver Overload Scale (ZBI), Weekly hourly load dedicated to the care of patients with dementia), the use of time in unpaid activities through an activity diary, provided by Argentine National Institute of Statistics and Census (INDEC), the Caregiver Activities Survey (CAS) and the Anxiety, Depression and Stress Scale (DASS-21). These questionnaires evaluate the conditions and characteristics of caregiving tasks and their impact on the caregiver in the context of ASPO. Additionally, it was recorded whether the person with dementia, the caregiver, or persons living with them had had COVID-19.Results:Descriptively, a disparity in frequency was observed in the gender of caregivers of persons with dementia, i.e., caregiving is inequitably distributed between men (24.11%) and women (75.89%). This difference hinders direct comparison between men and women. A regularized L2 regression was performed for the identification of predictors of caregiver overload identifying the number of caregiving hours (β=0.090), DAS depression (β=0.085), DASS anxiety (β=0.099) DASS stress (β=0.164), fear of Covid (0.141) and lower patient cognitive performance according to MMSE (β=-0.41) and to lesser extent sex as the greatest contributors to patient overload. Additionally, a mediation analysis was performed in which the factors number of caregiving hours (CAS; r= 0.254,r= 0.292,r= 0.252,r= 0.252,r= -0.37), being a primary caregiver and fear of Covid-19 (r= 0.335,r= 0.432,r= 0.402,r= -0.496) were found to be mediators of the effect between anxiety, depression, stress (DASS) and overload (ZBI).Conclusions:Caregivers of patients with dementia have suffered sequelae such as anxiety, stress, depression, and overload (caregivers’ burden) in the context of the COVID-19 virus spread and during mandatory preventive social isolation. Being a primary caregiver, dedicating more hours to caregiving, and fear of Covid-19 are factors that contribute significantly to caregiver burden and mediate between this burden and mood variables. Public policies to support caregivers and information about the disease could modify these variables and reduce caregiver burden.
95 Fear of Falling Associated with Decreased Attention and Executive Functioning in Caregivers
Authors: Thompson Sheila M , Morgan Eliza , Fairchild J Kaci 
Published: December 2023

Objective:Fear of falling is an anxiety-related phenomenon that is associated with increased risk of morbidity and mortality in older adults. Furthermore, a growing body of research has established the relationship between fear of falling and decreased cognitive functioning within various populations (i.e., older adult, multiple sclerosis, stroke survivors). Yet there is little information on the relationship between fear of falling and cognition outside of a geriatric context, with no publications investigating this relationship within informal caregivers. It is important to understand this relationship within caregiver populations because fear of falling may negatively impact caregivers’ ability to take care of themselves and their care recipients. The present study examines the relationship between fear of falling and cognitive function in informal caregivers.Participants and Methods:Fifty informal caregivers (86% female; 58% White; 10% Hispanic or Latino; 82% married; 53% with at least a bachelor’s degree; mean age = 57.76 ± 16.60 years) were assessed at the VA Palo Alto Health Care System in Palo Alto, CA. Fear of falling was measured via the Short Falls Efficacy Scale. Areas of cognitive functioning included verbal attention (Rey Auditory Verbal Learning Task [RAVLT] Trial 1), learning and memory (RAVLT Trials 1-5), delayed memory (RAVLT Delayed Recall), visual attention (Stroop Color, Stroop Word), and executive function (Stroop Color Word). Analyses included linear regressions with age as a covariate in all models.Results:Analyses revealed that fear of falling was significantly associated with decreased verbal attention (RAVLT Trial 1: ß=-0.34, p = 0.02, t = -2.35, CI = [-0.659, -0.051]) and with decreased executive functioning (Stroop Color Word: ß = -0.35, p < 0.001, t = -3.10, CI = [-4.097, -0.874]). Fear of falling was not significantly associated with learning and memory or visual attention.Conclusions:Fear of falling negatively impacts verbal attention and executive functioning, regardless of age. To our knowledge, this is the first study to examine the relationship between fear of falling and cognition outside of a geriatric population and within a caregiver sample. Findings suggest a need for additional assessment, research, and treatment of fear of falling within informal caregivers. Caregivers may need to be assessed for anxiety-related symptoms such as fear of falling on a more regular basis. A caregiver experiencing fear of falling, as well as difficulties with attention and executive functioning, can result in increased risk of functional and cognitive decline for both the caregiver and their care recipient. It is integral that future research investigates this relationship longitudinally to identify if the negative impact of fear of falling on cognition is reversible.
3 Race/Ethnicity-Related Differences in Volumetric Brain Measures in Persons with Multiple Sclerosis
Authors: Romän Cristina A. F. , Turney Indira C. , Mistry Ashish , Chiaravalloti Nancy , Dobryakova Ekaterina , Genova Helen , Sandroff Brian , Yao Brian , Wylie Glenn , DeLuca John 
Published: December 2023

Objective:Multiple sclerosis (MS) has historically been considered a syndrome that primarily affects White persons of northern European ancestry. This has been strongly disproven in recent decades with prevalence/incidence studies showing that MS impacts individuals from diverse backgrounds. The few studies available investigating clinical characteristics of MS across diverse groups have shown that Hispanic/Latinx/e (Latinx) and non-Hispanic Black/African American (NHB) persons with MS (pwMS) have more severe disease trajectories compared to non-Hispanic Whites (NHW), including an earlier age of disease onset, greater disability, and more severe symptoms overall. Changes in brain structure have been linked outcomes and MS-itself, but what remains understudied is how brain structure differs across race/ethnicity. As such, the current study aims to investigate volumetric brain differences in a diverse sample of pwMS.Participants and Methods:The sample (n=79) was compiled from multiple neuroimaging datasets and divided into three groups- Latinx (n=19), NHB (n=29), and NHW (n=32)- based on self-reported race/ethnicity. Participants completed demographic interviews and structural magnetic resonance imaging (MRI) scans. Neuroimaging data was visually inspected and processed in FreeSurfer (7.3.2). Volumetric measures for total gray matter, cortical gray matter, total white matter, and subcortical gray matter were used as the primary outcome measures.Results:A multivariate general linear model was used to examine volumetric brain differences across groups. Age and total intracranial volume were included as covariates. Results showed a significant effect of race/ethnicity (Pillai’s Trace=0.175, F(6, 148)=2.36, p=.033), indicating significant differences in volumetric brain metrics across race/ethnicity, namely for subcortical gray matter, total gray matter, and total white matter volumes. Post-hoc testing showed the Latinx group to have less subcortical gray matter, total gray matter, and total white matter than NHWs. There was a trend for the NHB versus NHW, with NHBs having less brain volume. No significant differences were observed between the Latinx and NHB groups. Lesion volume and regional gray matter volumes were also examined.Conclusions:To the authors’ knowledge, this is among the first studies to investigate structural brain differences across race/ethnicity in pwMS. Results point to disparities in brain volume across racial/ethnic groups with MS. These differences may partially underlie the differing trajectories observed in clinical characteristics across race/ethnicity. Future studies should include larger samples of diverse pwMS and examine the intersection of psychosocial and systemic factors (i.e., social determinants of health) and brain metrics to better understand the divergent disease trajectories observed across groups.
17 Performance Validity and Ethnicity
Authors: Hromas Gabrielle A. , Majors Emma , Davis Jeremy J. 
Published: December 2023

Objective:This study examined false positive rates of performance validity test (PVT) failure in a group of monolingual (English-speaking) White non-Hispanic/Latinx (non-HL), monolingual (English-speaking) Hispanic/Latinx (HL), and bilingual (English- and Spanish-speaking) HL patients evaluated at an academic medical center. Research on classification accuracy of embedded performance validity tests (PVTs) is limited in HL and bilingual populations. Cultural test biases or language differences could inaccurately cause scores below PVT cutoff levels.Participants and Methods:The project involved secondary analysis of a deidentified dataset (N=391). Participants were included if they were between the ages of 18 and 64, had data from the initial visit, had an IQ greater than or equal to 70, were not diagnosed with dementia or major or mild cognitive impairment, and identified as either White non-HL or HL. Participants were required to have completed at least two PVTs. Participants who were not administered the Test of Memory Malingering (TOMM; n=95) or who scored below a highly sensitive Trial 1 cutoff (<46; n=86) were excluded. The final sample included 210 participants, which included monolingual non-HL participants (n=114), monolingual HL participants (n=44), and bilingual HL participants (n=52). Failure rates on eight PVTs were examined by participant group: Reliable Digit Span (RDS), Auditory Verbal Learning Test Recognition (AVLT), Logical Memory Recognition (LM), Visual Reproduction Recognition (VR), Trail Making Test Ratio (TMT rat), Rey Complex Figure Test Recognition (RCFT), Semantic Word Generation (animals; SWG), and Finger Tapping (TAP).Results:Groups were not significantly different in age. Monolingual non-HL participants had completed more years of education than monolingual and bilingual HL groups (13.7, 12.7, and 12.8 years respectively). In the whole sample, 8.6% (n=18) failed two or more PVTs. In the monolingual non-HL group, 8.8% (n=10) failed two or more PVTs, while 9.1% (n=4) of the monolingual HL group and 7.7% (n=4) of the bilingual HL group failed two or more PVTs (n.s.). Within the monolingual non-HL test set, failure rates were above 10% on SWG (12.73%) and TAP (17.7%). Failure rates above 10% in the monolingual HL set were found on SWG (11.6%). Failure rates above 10% in bilingual HL measures were observed on SWG (13.5%) and TAP (10.8%).Conclusions:Total PVT failure rates did not significantly differ between groups. Across groups, performance was above a common false positive threshold of 10% on SWG. Monolingual non-HL and bilingual participants also had elevated failure rates on TAP.
53 Change in Cerebral Metabolite Concentrations Following Bariatric Surgery
Authors: Bottari Sarah , Cohen Ronald , Friedman Jeffrey , Porges Eric , Chen Alexa , Gunstad John , Woods Adam , Williamson John 
Published: December 2023

Objective:Obesity is associated with adverse effects on brain health, including increased risk for neurodegenerative diseases. Changes in cerebral metabolism may underlie or precede structural and functional brain changes. While bariatric surgery is known to be effective in inducing weight loss and improving obesity-related medical comorbidities, few studies have examined whether it may be able to improve brain metabolism. In the present study, we examined change in cerebral metabolite concentrations in participants with obesity who underwent bariatric surgery.Participants and Methods:35 patients with obesity (BMI > 35 kg/m2) were recruited from a bariatric surgery candidate nutrition class. They completed single voxel 1H-proton magnetic resonance spectroscopy at baseline (pre-surgery) and within one year post-surgery. Spectra were obtained from a large medial frontal brain region. Tissue-corrected absolute concentrations for metabolites including choline-containing compounds (Cho), myo-inositol (mI), N-acetylaspartate (NAA), creatine (Cr), and glutamate and glutamine (Glx) were determined using Osprey. Paired t-tests were used to examine within-subject change in metabolite concentrations, and correlations were used to relate these changes to other health-related outcomes, including weight loss and glycemic control.Results:Bariatric surgery was associated with a reduction in cerebral Cho (f[34j = -3.79, p < 0.001, d = -0.64) and mI (f[34] = -2.81, p < 0.01, d = -0.47) concentrations. There were no significant changes in NAA, Glx, or Cr concentrations. Reductions in Cho were associated with greater weight loss (r = 0.40, p < 0.05), and reductions in mI were associated with greater reductions in HbA1c (r = 0.44, p < 0.05).Conclusions:Participants who underwent bariatric surgery exhibited reductions in cerebral Cho and mI concentrations, which were associated with improvements in weight loss and glycemic control. Given that elevated levels of Cho and mI have been implicated in neuroinflammation, reduction in these metabolites after bariatric surgery may reflect amelioration of obesity-related neuroinflammatory processes. As such, our results provide evidence that bariatric surgery may improve brain health and metabolism in individuals with obesity.
60 Neural Correlates of the Self-Reference Effect: Neuronal Mechanisms Supporting Self-Referential Encoding
Authors: Hampton Andreina , Tacikowski Pawel , Fried Itzhak 
Published: December 2023

Objective:Self-concept is a mental representation of the self—an internal sense of personal identity. This complex representation is unique to the human mind. Behavioral studies on self-concept have demonstrated that self-relevant information is remembered better than other types of information, a phenomenon commonly known as the “self-reference effect” (SRE). However, the underlying neural mechanisms of SRE remain largely unknown.Participants and Methods:Here, we recorded neural activity from ∼600 neurons from 15 neurosurgical epilepsy patients, who were implanted with depth electrodes for seizure monitoring. The SRE paradigm consisted of an incidental learning (encoding) task and subsequent memory recognition test. During the incidental learning task, participants were asked to rate various personality traits in three distinct encoding conditions: the self, a friend, and a celebrity. In the recognition part of the task, participants were asked to distinguish between traits that were presented during the encoding phase (old) and traits that were not presented (new).Results:Our behavioral findings showed the highest memory accuracy on the recognition test for traits that were associated with the “self” condition, which is consistent with previous studies on SRE. Additionally, we found that traits associated with the “friend” category were more accurately recognized than those associated with a celebrity, indicating that personally familiar information—even if not self-related— improves memory recognition. Through single-unit analyses from target brain regions, including the medial temporal lobe (MTL) and medial prefrontal cortex (mPFC), we identified unique patterns of neural activity during the memory encoding phase, specifically increased responses during self-referential encoding in a subset of the neuronal population.Conclusions:Future analyses will explore the relationship between increased MTL activity during self-referential encoding and improved memory recognition of traits rated in relation to the self, and network interactions between MTL and mPFC in self-oriented memory processes.
63 A Literature Review of Cortical Mapping, fMRI, and Standards of Care in Pediatric Epilepsy Surgical Workup
Authors: Cernokova Ivana , Owens Ronnise D , del Valle Martinez Eva , Semaan Nicole , Bergeron Coralie , Bearden Donald J. , Ono Kim E 
Published: December 2023

Objective:Epilepsy includes recurrent, unprovoked seizures and affects 470,000 children in the US, of which 7% have drug-resistant epilepsy due to failing two or more antiseizure medication trials. For some patients with drug-resistant epilepsy, surgery has been successful in reducing seizure burden. Functional MRI (fMRI) and intracranial mapping of neurocognitive functions, especially language, are increasingly done to assess potential functional loss from epilepsy surgery. However, these procedures vary by medical institute. The purpose of this review was to examine published literature on fMRI and intracranial mapping procedures for pediatric epilepsy surgery workup toward development of a standardized protocol that can be used across institutes as a guide to standard-of-care best practices for predicting loss of function associated with epilepsy surgery.Participants and Methods:Our literature review includes information from 8 electronic databases for peer-reviewed, English language studies of evaluation for pediatric epilepsy surgery candidacy. Thirty-one studies were selected based on inclusion criteria. Only studies including fMRI and intracranial mapping conducted with pediatric patients being worked up for epilepsy surgery were selected.Results:Our review revealed that the most common task used in fMRI and intracranial mapping procedures is visual-object naming, but type of naming tasks and the way they are administered varies widely across medical institutes and includes published measures and those created on site. Variability makes examining findings across studies and designing best practice for these procedures challenging.Conclusions:Creating gold-standard procedures for fMRI and intracranial mapping administration for epilepsy surgery evaluations is critical in optimizing treatment and functional outcomes for our pediatric patients. Our review is an initial step in this process.
67 Blinding and Double-Blinding of HD-tDCS in Double-Blind, Randomized Controlled Trials
Authors: Harrie Ashley , El Jamal Carine , Padgett Michael , Rahman-Filipiak Annalise , Hampstead Benjamin M 
Published: December 2023

Objective:High-definition transcranial direct current stimulation (HD-tDCS) is a non-invasive brain stimulation technique shown to modulate neuronal networks. In order for HD-tDCS to be used in randomized, placebo-controlled clinical trials, it is critical to have methods that enable blinding. Some research has shown that sham stimulation is an effective blind in tDCS. However, few studies have investigated the double-blinding of HD-tDCS, especially at intensities greater than 2mA. We address this knowledge gap by examining the blinding and double-blinding of HD-tDCS among a mixed neurologic sample of older adults.Participants and Methods:A sample of 240 older adults (Mage = 72.21±8.94) with various clinical diagnoses (Normal Cognition = 34, Amnestic MCI [aMCI] = 172, Dementia-Alzheimer’s Type [DAT] = 27, Other = 7) were recruited through five double-blind, randomized controlled trials. All participants were stimulation naive at their first session and received one to thirty sessions of 20- or 30-minutes of active (n=1472) or sham (n=681) stimulation at total amplitudes of 2mA, 4mA, or 6mA. At the start of each stimulation session, a study team member entered a code into the tDCS unit, and the electrical current was gradually ramped up to the specified (blinded) amplitude over a period of 30 seconds. The current remained at this level for the specified amount of time in the active condition (e.g., 20-minutes) but was ramped down over the next 30 seconds for those in the sham condition. This ramp up/down process was repeated in the final minute (e.g., 20th minute) in the sham session to provide both primacy and recency effects. After each active or sham session, participants were asked whether they received 'real’ or sham stimulation. One study also asked a study team member if they believed the participant received real or sham stimulation at two primary outcome endpoints.Results:We used Fisher’s Exact tests to evaluate the efficacy of our blinding and double-blinding procedures. In stimulation naive participants receiving their first session, there were no differences in accuracy, suggesting adequate blinding. We also examined participant blinding across all sessions to determine whether repeated HD-tDCS exposure might impact blinding. Across all sessions, participants in the sham condition were more likely to endorse being in the 'real’ (active) condition, again suggesting adequate blinding. There were no significant group differences for active versus sham in the frequency of the study team correctly stating the participant’s condition, suggesting sufficient double-blinding. No significant differences were found in study team blinding when data from the 2mA versus 4mA to 6mA were analyzed separately.Conclusions:These results suggest that the HD-tDCS sham method is an effective blind and double-blind for HD-tDCS in clinical trials, even at total amplitudes as high as 6mA.