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Accurate diagnosis of bipolar disorder (BPD) is difficult in clinical practice, with an average delay between symptom onset and diagnosis of about 7 years. A depressive episode often precedes the first manic episode, making it difficult to distinguish BPD from unipolar major depressive disorder (MDD).
Aims
We use genome-wide association analyses (GWAS) to identify differential genetic factors and to develop predictors based on polygenic risk scores (PRS) that may aid early differential diagnosis.
Method
Based on individual genotypes from case–control cohorts of BPD and MDD shared through the Psychiatric Genomics Consortium, we compile case–case–control cohorts, applying a careful quality control procedure. In a resulting cohort of 51 149 individuals (15 532 BPD patients, 12 920 MDD patients and 22 697 controls), we perform a variety of GWAS and PRS analyses.
Results
Although our GWAS is not well powered to identify genome-wide significant loci, we find significant chip heritability and demonstrate the ability of the resulting PRS to distinguish BPD from MDD, including BPD cases with depressive onset (BPD-D). We replicate our PRS findings in an independent Danish cohort (iPSYCH 2015, N = 25 966). We observe strong genetic correlation between our case–case GWAS and that of case–control BPD.
Conclusions
We find that MDD and BPD, including BPD-D are genetically distinct. Our findings support that controls, MDD and BPD patients primarily lie on a continuum of genetic risk. Future studies with larger and richer samples will likely yield a better understanding of these findings and enable the development of better genetic predictors distinguishing BPD and, importantly, BPD-D from MDD.
Yuan and Chan (Psychometrika, 76, 670–690, 2011) recently showed how to compute the covariance matrix of standardized regression coefficients from covariances. In this paper, we describe a method for computing this covariance matrix from correlations. Next, we describe an asymptotic distribution-free (ADF; Browne in British Journal of Mathematical and Statistical Psychology, 37, 62–83, 1984) method for computing the covariance matrix of standardized regression coefficients. We show that the ADF method works well with nonnormal data in moderate-to-large samples using both simulated and real-data examples. R code (R Development Core Team, 2012) is available from the authors or through the Psychometrika online repository for supplementary materials.
A general theory on the use of correlation weights in linear prediction has yet to be proposed. In this paper we take initial steps in developing such a theory by describing the conditions under which correlation weights perform well in population regression models. Using OLS weights as a comparison, we define cases in which the two weighting systems yield maximally correlated composites and when they yield minimally similar weights. We then derive the least squares weights (for any set of predictors) that yield the largest drop in R2 (the coefficient of determination) when switching to correlation weights. Our findings suggest that two characteristics of a model/data combination are especially important in determining the effectiveness of correlation weights: (1) the condition number of the predictor correlation matrix, Rxx, and (2) the orientation of the correlation weights to the latent vectors of Rxx.
In a multiple regression analysis with three or more predictors, every set of alternate weights belongs to an infinite class of “fungible weights” (Waller, Psychometrica, in press) that yields identical SSE (sum of squared errors) and R2 values. When the R2 using the alternate weights is a fixed value, fungible weights (ai) that yield the maximum or minimum cosine with an OLS weight vector (b) are called “fungible extrema.” We describe two methods for locating fungible extrema and we report R code (R Development Core Team, 2007) for one of the methods. We then describe a new approach for populating a class of fungible weights that is derived from the geometry of alternate regression weights. Finally, we illustrate how fungible weights can be profitably used to gauge parameter sensitivity in linear models by locating the fungible extrema of a regression model of executive compensation (Horton & Guerard, Commun. Stat. Simul. Comput. 14:441–448, 1985).
Cannabis use and familial vulnerability to psychosis have been associated with social cognition deficits. This study examined the potential relationship between cannabis use and cognitive biases underlying social cognition and functioning in patients with first episode psychosis (FEP), their siblings, and controls.
Methods
We analyzed a sample of 543 participants with FEP, 203 siblings, and 1168 controls from the EU-GEI study using a correlational design. We used logistic regression analyses to examine the influence of clinical group, lifetime cannabis use frequency, and potency of cannabis use on cognitive biases, accounting for demographic and cognitive variables.
Results
FEP patients showed increased odds of facial recognition processing (FRP) deficits (OR = 1.642, CI 1.123–2.402) relative to controls but not of speech illusions (SI) or jumping to conclusions (JTC) bias, with no statistically significant differences relative to siblings. Daily and occasional lifetime cannabis use were associated with decreased odds of SI (OR = 0.605, CI 0.368–0.997 and OR = 0.646, CI 0.457–0.913 respectively) and JTC bias (OR = 0.625, CI 0.422–0.925 and OR = 0.602, CI 0.460–0.787 respectively) compared with lifetime abstinence, but not with FRP deficits, in the whole sample. Within the cannabis user group, low-potency cannabis use was associated with increased odds of SI (OR = 1.829, CI 1.297–2.578, FRP deficits (OR = 1.393, CI 1.031–1.882, and JTC (OR = 1.661, CI 1.271–2.171) relative to high-potency cannabis use, with comparable effects in the three clinical groups.
Conclusions
Our findings suggest increased odds of cognitive biases in FEP patients who have never used cannabis and in low-potency users. Future studies should elucidate this association and its potential implications.
Positive, negative and disorganised psychotic symptom dimensions are associated with clinical and developmental variables, but differing definitions complicate interpretation. Additionally, some variables have had little investigation.
Aims
To investigate associations of psychotic symptom dimensions with clinical and developmental variables, and familial aggregation of symptom dimensions, in multiple samples employing the same definitions.
Method
We investigated associations between lifetime symptom dimensions and clinical and developmental variables in two twin and two general psychosis samples. Dimension symptom scores and most other variables were from the Operational Criteria Checklist. We used logistic regression in generalised linear mixed models for combined sample analysis (n = 875 probands). We also investigated correlations of dimensions within monozygotic (MZ) twin pairs concordant for psychosis (n = 96 pairs).
Results
Higher symptom scores on all three dimensions were associated with poor premorbid social adjustment, never marrying/cohabiting and earlier age at onset, and with a chronic course, most strongly for the negative dimension. The positive dimension was also associated with Black and minority ethnicity and lifetime cannabis use; the negative dimension with male gender; and the disorganised dimension with gradual onset, lower premorbid IQ and substantial within twin-pair correlation. In secondary analysis, disorganised symptoms in MZ twin probands were associated with lower premorbid IQ in their co-twins.
Conclusions
These results confirm associations that dimensions share in common and strengthen the evidence for distinct associations of co-occurring positive symptoms with ethnic minority status, negative symptoms with male gender and disorganised symptoms with substantial familial influences, which may overlap with influences on premorbid IQ.
Field experiments were conducted at Clayton and Rocky Mount, NC, during summer 2020 to determine the growth and fecundity of Palmer amaranth plants that survived glufosinate with and without grass competition in cotton. Glufosinate (590 g ai ha−1) was applied to Palmer amaranth early postemergence (5 cm tall), mid-postemergence (7 to 10 cm tall), and late postemergence (>10 cm tall) and at orthogonal combinations of those timings. Nontreated Palmer amaranth was grown in weedy, weed-free in-crop (WFIC) and weed-free fallow (WFNC) conditions for comparisons. Palmer amaranth control decreased as larger plants were treated; no plants survived the sequential glufosinate applications in both experiments. The apical and circumferential growth of Palmer amaranth surviving glufosinate treatments was reduced by more than 44% compared to the WFIC and WFNC Palmer amaranth in both experiments. The biomass of Palmer amaranth plants surviving glufosinate was reduced by more than 62% when compared with the WFIC and WFNC in all experiments. The fecundity of Palmer amaranth surviving glufosinate treatments was reduced by more than 73% compared to WFNC Palmer amaranth in all experiments. Remarkably, the plants that survived glufosinate were fecund as WFIC plants only in the Grass Competition experiment. The results prove that despite decreased vegetative growth of Palmer amaranth surviving glufosinate treatment, plants remain fecund and can be fecund as nontreated plants in cotton. These results suggest that a glufosinate-treated grass weed may not have a significant interspecific competition effect on Palmer amaranth that survives glufosinate. Glufosinate should be applied to 5 to 7 cm Palmer amaranth to cease vegetative and reproductive capacities.
Globally, mental disorders account for almost 20% of disease burden and there is growing evidence that mental disorders are associated with various social determinants. Tackling the United Nations Sustainable Development Goals (UN SDGs), which address known social determinants of mental disorders, may be an effective way to reduce the global burden of mental disorders.
Objectives
To examine the evidence base for interventions that seek to improve mental health through targeting the social determinants of mental disorders.
Methods
We conducted a systematic review of reviews, using a five-domain conceptual framework which aligns with the UN SDGs (PROSPERO registration: CRD42022361534). PubMed, PsycInfo, and Scopus were searched from 01 January 2012 until 05 October 2022. Citation follow-up and expert consultation were used to identify additional studies. Systematic reviews including interventions seeking to change or improve a social determinant of mental disorders were eligible for inclusion. Study screening, selection, data extraction, and quality appraisal were conducted in accordance with PRISMA guidelines. The AMSTAR-2 was used to assess included reviews and results were narratively synthesised.
Results
Over 20,000 records were screened, and 101 eligible reviews were included. Most reviews were of low, or critically low, quality. Reviews included interventions which targeted sociocultural (n = 31), economic (n = 24), environmental (n = 19), demographic (n = 15), and neighbourhood (n = 8) determinants of mental disorders. Interventions demonstrating the greatest promise for improved mental health from high and moderate quality reviews (n = 37) included: digital and brief advocacy interventions for female survivors of intimate partner violence; cash transfers for people in low-middle-income countries; improved work schedules, parenting programs, and job clubs in the work environment; psychosocial support programs for vulnerable individuals following environmental events; and social and emotional learning programs for school students. Few effective neighbourhood-level interventions were identified.
Conclusions
This review presents interventions with the strongest evidence base for the prevention of mental disorders and highlights synergies where addressing the UN SDGs can be beneficial for mental health. A range of issues across the literature were identified, including barriers to conducting randomised controlled trials and lack of follow-up limiting the ability to measure long-term mental health outcomes. Interdisciplinary and novel approaches to intervention design, implementation, and evaluation are required to improve the social circumstances and mental health experienced by individuals, communities, and populations.
Field experiments were conducted at Clayton and Rocky Mount, North Carolina, during the summer of 2020 to determine the growth and fecundity of Palmer amaranth plants that survived glufosinate with and without grass competition in soybean crops. Glufosinate (590 g ai ha−1) was applied at early postemergence (when Palmer amaranth plants were 5 cm tall), mid-postemergence (7–10 cm), and late postemergence (>10 cm) and at orthogonal combinations of those timings. Nontreated Palmer amaranth was grown in weedy (i.e., intraspecific and grass competition), weed-free in-crop (WFIC), and weed-free fallow (WFNC) conditions for comparisons. No Palmer amaranth plants survived the sequential glufosinate applications and control decreased as the plants were treated at a larger size in both experiments. The apical and circumferential growth rate of Palmer amaranth surviving glufosinate was reduced by more than 44% compared with the WFNC Palmer amaranth. The biomass of Palmer amaranth plants that survived glufosinate was reduced by more than 87% compared with the WFNC Palmer amaranth. The fecundity of Palmer amaranth that survived glufosinate was reduced by more than 70% compared with WFNC Palmer amaranth. Palmer amaranth plants that survived glufosinate were as fecund as the WFIC Palmer amaranth in both experiments in soybean fields. The results prove that despite the significant vegetative growth rate decrease of Palmer amaranth that survived glufosinate, plants can be as fecund as nontreated plants. The trends in growth and fecundity of Palmer amaranth that survives glufosinate with and without grass competition were similar. These results suggest that glufosinate-treated grass weeds may not reduce the growth or fecundity of Palmer amaranth that survives glufosinate.
OBJECTIVES/GOALS: Seeking ways to support teams in the preparation for and the implementation of the new National Institutes of Health (NIH) Policy for Data Management and Sharing (DMSP), the integrated Translational Health Research Institute of Virginia (iTHRIV) partnered with the UVA Health Sciences Library to develop training and resources for researchers. METHODS/STUDY POPULATION: Health sciences librarians and iTHRIV (an NIH-NCATS supported Clinical Translational Research Institute) convened a Working Group, inviting representatives from central and unit-specific research support offices (e.g. the Comprehensive Cancer Center), research compliance, regulatory affairs, sponsored programs, institutional review boards, libraries, and data science to review and discuss the DMSP requirements. After an initial orientation to the policy, the group reviewed existing public resources and solicited feedback about steps to best support UVA researchers in compliance. Leveraging the broad expertise of the group, the team provides guidance to researchers on writing the DMS plan and choosing a data repository, and provides tools and templates to support implementation of the policy. RESULTS/ANTICIPATED RESULTS: A library-created website provided policy guidance, including links to NIH-hosted information, resources created by other institutions, and new UVA-specific templates and suggested proposal language. Librarians led a webinar on the new policy and UVA resources which included a speaker from UVA regulatory affairs to describe the new DMSP requirements, and a tour of the new guide. The guide has been viewed over 5000 times to date and librarians have provided consultations and training to individuals and departments. Current plans include developing a user satisfaction survey, reviewing DMSP feedback from submitted proposals, and incorporating lessons learned into the website and future training. DISCUSSION/SIGNIFICANCE: The collaboration between iTHRIV and the Health Sciences Library to support the NIH Data Management and Sharing Policy was a successful partnership that provided leadership at the institutional level to communicate with and engage researchers and utilized the library’s web presence, expertise, and service model to provide direct support.
OBJECTIVES/GOALS: The COVID-19 pandemic disrupted established social support networks (faith-based, community, family, friends), resulting in unprecedented health-related, financial, and employment challenges among African Americans (AAs). This study explores the psychosocial influences of the pandemic on the health and wellness of AAs. METHODS/STUDY POPULATION: The FAITH! (Fostering African-American Improvement in Total Health!) Program, an academic-community partnership with AA churches, shifted focus to COVID-19 prevention in AA communities. Funded by the Mayo Clinic Center for Clinical and Translation Sciences, this cross-sectional study recruited AA adults from FAITH!-affiliated churches and social media to complete a survey exploring the personal impact of the pandemic from hardships (e.g., food and housing insecurity, paying utilities) on healthy lifestyle (HL). The primary outcome was difficulty maintaining a HL during the pandemic. Logistic regression (odds ratios and associated 95% confidence intervals (CIs)) was used to examine the associations between difficulty maintaining a HL and factors including COVID-19 hardships and mental health. RESULTS/ANTICIPATED RESULTS: Participants (N=169, 71.4% female, 41.4% essential workers) had a mean age [SD] of 49.4 [14.9] years. Over half (91/169, 54%) reported difficulty maintaining a HL. Those reporting unemployment (OR 2.3; 95% CI [1.2,4.4]; p=0.008), difficulty paying rent (OR 4.1; 95% CI [2.1,8.6]; p<0.001), or food/utilities (OR 5.5; 95% CI [2.7,11.5]; p<0.001) all had greater odds of difficulty maintaining a HL. High stress (≥5/10, scale 1-10) was associated with difficulty maintaining a HL (OR 4.1; 95% CI [2.1,8.5]; p<0.001) compared to AAs with low stress. Negative mental health (depression (OR 3.4; 95% CI [1.0,13.7]; p<0.001), anger (OR 2.5; 95% CI [0.5,18.9]; p=0.005), and nervousness (OR 4.1; 95% CI [1.1,19.5]; p=0.003) was associated with difficulty maintaining a HL compared to AAs with positive mental health. DISCUSSION/SIGNIFICANCE: Our study findings revealed that COVID-19 hardships, stress, and negative mental health impacted the ability of AAs to maintain a HL. These issues should be considered in the design and implementation of community-based health programs to promote healthy living during future public health emergencies.
Odd Radio Circles (ORCs) are a class of low surface brightness, circular objects approximately one arcminute in diameter. ORCs were recently discovered in the Australian Square Kilometre Array Pathfinder (ASKAP) data and subsequently confirmed with follow-up observations on other instruments, yet their origins remain uncertain. In this paper, we suggest that ORCs could be remnant lobes of powerful radio galaxies, re-energised by the passage of a shock. Using relativistic hydrodynamic simulations with synchrotron emission calculated in post-processing, we show that buoyant evolution of remnant radio lobes is alone too slow to produce the observed ORC morphology. However, the passage of a shock can produce both filled and edge-brightnened ORC-like morphologies for a wide variety of shock and observing orientations. Circular ORCs are predicted to have host galaxies near the geometric centre of the radio emission, consistent with observations of these objects. Significantly offset hosts are possible for elliptical ORCs, potentially causing challenges for accurate host galaxy identification. Observed ORC number counts are broadly consistent with a paradigm in which moderately powerful radio galaxies are their progenitors.
There are numerous challenges pertaining to epilepsy care across Ontario, including Epilepsy Monitoring Unit (EMU) bed pressures, surgical access and community supports. We sampled the current clinical, community and operational state of Ontario epilepsy centres and community epilepsy agencies post COVID-19 pandemic. A 44-item survey was distributed to all 11 district and regional adult and paediatric Ontario epilepsy centres. Qualitative responses were collected from community epilepsy agencies. Results revealed ongoing gaps in epilepsy care across Ontario, with EMU bed pressures and labour shortages being limiting factors. A clinical network advising the Ontario Ministry of Health will improve access to epilepsy care.
A combined powder X-ray diffraction (XRD) and X-ray absorption (XAS) study of Fe(III) cation ordering within pyroaurite is described. It is concluded that there is no correlation between Fe(III) cation positions over distances of a few tens of angstroms, but that there is a very high level of local ordering, involving the absence of Fe(III)-Fe(III) neighbors. These observations are rationalized in terms of a significant frequency of lattice defects in the form of cation vacancies or Mg for Fe(III) substitutions. These results are expected to be generalizable to other M(II)/M(III) layered double hydroxides (LDHs), but are in contrast to the long-range cation ordering observed in Li/Al LDHs. This raises the interesting possibility of differing properties and stabilities based on the degree of cation ordering.
Clay minerals are abundant in soils and sediments and often contain Fe. Some varieties, such as nontronites, contain as much as 40 wt.% Fe2O3 within their molecular structure. Several studies have shown that various Fe-reducing micro-organisms can use ferric iron in Fe-bearing clay minerals as their terminal electron acceptor, thereby reducing it to ferrous iron. Laboratory experiments have also demonstrated that chemically or bacterially reduced clays can promote the reductive degradation of various organics, including chlorinated pesticides and nitroaromatics. Therefore, Fe-bearing clays may play a crucial role in the natural attenuation of various redox-sensitive contaminants in soils and sediments. Although the organochlorinated pesticide p,p′-DDT is one of the most abundant and recalcitrant sources of contamination in many parts of the world, the impact of reduced Fe-bearing clays on its degradation has never been documented. The purpose of the present study was to evaluate the extent of degradation of p,p′-DDT during the bacterial reduction of Fe(III) in an Fe-rich clay. Microcosm experiments were conducted under anaerobic conditions using nontronite (sample NAu-2) spiked with p,p′-DDT and the metal-reducing bacteria Shewanella oneidensis MR-1. Similar experiments were conducted using a sand sample to better ascertain the true impact of the clay vs. the bacteria on the degradation of DDT. Samples were analyzed for DDT and degradation products after 0, 3, and 6 weeks of incubation at 30°C. Results revealed a progressive decrease in p,p′-DDT and increase in p,p′-DDD concentrations in the clay experiments compared to sand and abiotic controls, indicating that Fe-bearing clays may substantially contribute toward the reductive degradation of DDT in soils and sediments. These new findings further demonstrate the impact that clay materials can have on the natural attenuation of pollutants in natural and artificial systems and open new avenues for the passive treatment of contaminated land.
In persons with severe psychiatric disorders, distinct neurocognitive profiles hold differential associations to positive, negative and disorganized symptom dimensions of psychosis. These patterns portend specific functional outcomes, treatment efficacy, and prognoses. Similar associations have not been established in multimorbid samples in which persons present with a complex array of psychiatric symptoms. The objective of this study was to (1) establish neurocognitive profiles in a multimorbid, marginalized sample and (2) investigate their pattern(s) of association with psychiatric symptom dimensions and psychosocial outcomes.
Participants and Methods:
Participants (n=370; Mage = 45 years; 74% male) were precariously housed, substance-using adults with multimorbidity, recruited from Single-Room Occupancy hotels and a community court within the Downtown Eastside of Vancouver, BC, Canada. Data were collected as part of a longitudinal examination consisting of annual, bi-annual, and monthly neurocognitive, psychosocial, and psychiatric assessments. Neurocognitive scores were combined into five cognitive domains (Attentional Control [AC]; Processing Speed [PS]; Fluid Reasoning [Problem Solving and Reversal Learning; Gf]; Encoding and Retrieval [ER]; and Decision Making [DM]) and submitted to a latent profile analysis. The resulting profiles capturing neurocognition were validated on sociodemographic and clinical variables. Finally, the profiles were compared across previously validated, population-distinct factors derived from the Positive and Negative Syndrome Scale (PANSS), as well as on measures of psychosocial functioning.
Results:
An optimal goodness-of-fit was reached for a three-profile model (BLRT=127.86, p=.01). Profile 1 (n=207, 55.9%) showed stronger neurocognition (all p<.05), with a within-profile strength in Gf (p<.001). With the exception of ER, Profile 2 (n=109, 29.5%) exhibited inferior neurocognition across all indicators compared to Profile 1 (all p <.05); yet showed a relative, within-profile strength in Gf (p < .01). Profile 3 (n=54, 14.6%) generally displayed comparable impairments to Profile 2. Additionally, their performance on Gf was remarkably low compared to Profiles 1 and 2 (p<.001). Psychiatrically, compared to Profile 1, Profile 2 exhibited more positive/disorganized symptoms and general psychopathology, as well as higher total PANSS (all p <.05), whereas Profile 3 showed the poorest insight/awareness (p<.01). Profiles 2 and 3 had lower levels of adaptive functioning and work productivity compared to Profile 1 (all p<.01).
Conclusions:
Three neurocognitive profiles were detected in a sample of precariously housed adults with multimorbidity: one profile of comparatively higher neurocognitive capacity, with less symptoms of psychosis and better psychosocial functioning; a second profile of comparatively poorer neurocognition and psychosocial functioning, with more symptoms of psychosis; and a third profile with a severe deficit in fluid reasoning and poor insight and awareness. Given their poor insight, the third profile may be comprised of particularly vulnerable persons at greater risk of unmet healthcare needs. Interventions to improve these individuals' understanding of their personal health risks might facilitate their capacity to access services. Conversely, individuals from Profile 2 may benefit from outreach programs focusing on medication access and adherence to address their symptoms of psychosis. In sum, our findings suggest that the confluence of neurocognition and psychiatric symptoms may implicate unique treatment approaches and outcomes in precariously-housed persons with multimorbid conditions.
Cognitive dysfunction is prominent in homeless and precariously housed persons, and memory dysfunction is the most pervasive domain. The presence of multimorbid physical and mental illness suggests that several underlying mechanisms of memory impairment may be at play. The serial position phenomenon describes the tendency to best recall the beginning (primacy effect) and last (recency effect) words on a supra-span wordlist. Recency recall engages executive and working-memory systems, whereas primacy recall depends on long-term memory. This study investigates memory dysfunction in a homeless and precariously housed sample by identifying and characterizing unique subtypes of serial position profiles on a test of verbal memory.
Participants and Methods:
Data were used from a 20-year study of homeless and precariously housed adults recruited from an impoverished neighbourhood in Vancouver, Canada. Participants were sub-grouped according to their serial position profile on the Hopkins Verbal Learning Test-Revised using a latent profile analysis (LPA; n = 411). Paired samples t-tests were conducted to determine differences in percent recall from each word-list region within classes. Linear regression analyses were used to examine between-class differences in mean serial position scores and other cognitive measures (memory, attention, processing speed, cognitive control). Covariates included age, sex, and education.
Results:
LPA identified two profiles characterized by (1) reduced primacy relative to recency (RP; n = 150); and (2) reduced recency relative to primacy (RR; n = 261). Pairwise comparisons within the RP class showed that recency was better than primacy (p < .001, d = .66) and middle recall (p < .001, d = .52), with no difference between primacy and middle recall (p = .68, d = .04). All pairwise comparisons differed within the RR class (primacy > middle recall: p < .001, d = 1.85; primacy > recency recall: p < .001, d = 1.32; middle > recency recall: p < .05, d = .132). The RP class had worse performance on measures of total immediate (ß = .47, p < .001) and delayed verbal recall (ß = .32, p < .001); processing speed (ß = .20, p < .001); and cognitive control (ß = .22, p < .001). The RR class made more repetition errors (ß = .25, p < .001).
Conclusions:
These findings support substantial heterogeneity in memory functioning in homeless and precariously housed individuals. The RP profile was characterized by poorer cognitive functioning across several domains, which suggests multiple contributions to memory impairment, including dysfunction of long-term memory circuitry. The RR profile with their higher number of repetition errors, may experience difficulties with self-monitoring in verbal learning. Subsequent studies will explore the neurobiological underpinnings of these subgroups to further characterize profiles and identify targets for cognitive intervention.