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1.
Neurosci Biobehav Rev ; 162: 105697, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38710422

RESUMO

The lifespan is influenced by adverse childhood experiences that create predispositions to poor health outcomes. Here we propose an allostatic framework of childhood experiences and their impact on health across the lifespan, focusing on Latin American and Caribbean countries. This region is marked by significant social and health inequalities nested in environmental and social stressors, such as exposure to pollution, violence, and nutritional deficiencies, which critically influence current and later-life health outcomes. We review several manifestations across cognition, behavior, and the body, observed at the psychological (e.g., cognitive, socioemotional, and behavioral dysfunctions), brain (e.g., alteration of the development, structure, and function of the brain), and physiological levels (e.g., dysregulation of the body systems and damage to organs). To address the complexity of the interactions between environmental and health-related factors, we present an allostatic framework regarding the cumulative burden of environmental stressors on physiological systems (e.g., cardiovascular, metabolic, immune, and neuroendocrine) related to health across the life course. Lastly, we explore the relevance of this allostatic integrative approach in informing regional interventions and public policy recommendations. We also propose a research agenda, potentially providing detailed profiling and personalized care by assessing the social and environmental conditions. This framework could facilitate the delivery of evidence-based interventions and informed childhood-centered policy-making.

2.
J Nutr Health Aging ; 28(5): 100246, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38669857

RESUMO

The global increase in the population of older persons has profound inter-sectoral implications, necessitating the development of age-friendly initiatives at the global and national levels. While progress has been relatively slower across Sub-Saharan African countries, highlighting existing commendable initiatives is essential to identify the current gaps and promote the development of strategies and interventions to promote age-friendly societies. This mini-review highlights some of the key initiatives in Ghana in the areas of policy, healthcare, finance, social services, education and research and in promoting dementia-friendly communities.

3.
Brain Commun ; 6(2): fcae046, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38444908

RESUMO

A reduction in the volume of the thalamus and its nuclei has been reported in Alzheimer's disease, mild cognitive impairment and asymptomatic individuals with risk factors for early-onset Alzheimer's disease. Some studies have reported thalamic atrophy to occur prior to hippocampal atrophy, suggesting thalamic pathology may be an early sign of cognitive decline. We aimed to investigate volumetric differences in thalamic nuclei in middle-aged, cognitively unimpaired people with respect to dementia family history and apolipoprotein ε4 allele carriership and the relationship with cognition. Seven hundred participants aged 40-59 years were recruited into the PREVENT Dementia study. Individuals were stratified according to dementia risk (approximately half with and without parental dementia history). The subnuclei of the thalamus of 645 participants were segmented on T1-weighted 3 T MRI scans using FreeSurfer 7.1.0. Thalamic nuclei were grouped into six regions: (i) anterior, (ii) lateral, (iii) ventral, (iv) intralaminar, (v) medial and (vi) posterior. Cognitive performance was evaluated using the computerized assessment of the information-processing battery. Robust linear regression was used to analyse differences in thalamic nuclei volumes and their association with cognitive performance, with age, sex, total intracranial volume and years of education as covariates and false discovery rate correction for multiple comparisons. We did not find significant volumetric differences in the thalamus or its subregions, which survived false discovery rate correction, with respect to first-degree family history of dementia or apolipoprotein ε4 allele status. Greater age was associated with smaller volumes of thalamic subregions, except for the medial thalamus, but only in those without a dementia family history. A larger volume of the mediodorsal medial nucleus (Pfalse discovery rate = 0.019) was associated with a faster processing speed in those without a dementia family history. Larger volumes of the thalamus (P = 0.016) and posterior thalamus (Pfalse discovery rate = 0.022) were associated with significantly worse performance in the immediate recall test in apolipoprotein ε4 allele carriers. We did not find significant volumetric differences in thalamic subregions in relation to dementia risk but did identify an interaction between dementia family history and age. Larger medial thalamic nuclei may exert a protective effect on cognitive performance in individuals without a dementia family history but have little effect on those with a dementia family history. Larger volumes of posterior thalamic nuclei were associated with worse recall in apolipoprotein ε4 carriers. Our results could represent initial dysregulation in the disease process; further study is needed with functional imaging and longitudinal analysis.

4.
J Health Psychol ; : 13591053241235846, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38439512

RESUMO

Befriending services are often delivered to older adults with a view to improving social connectedness, but they may also lead to improved health. The objective of the current study was to explore potential mechanisms through which befriending services might impact the health of older adults. Data were collected from 13 befriendee-befriender dyads (n = 26), using a constructivist grounded theory and dyadic analytic approach. Potential mechanisms were described, using a realist evaluative framework of mechanistic processes in a complex intervention context. Five mechanisms of action triggered by the intervention were identified: supporting health behaviours; providing emotional support; improving mood; getting cognitive stimulation and novelty; and providing opportunities for socialising. We identified five potential mechanisms through which befriending services might impact health for older people. Our results suggest potential mechanisms through which befriending might positively impact the health of older people, and which should be evaluated empirically in future research.

5.
Brain Commun ; 6(1): fcad351, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38384997

RESUMO

The apolipoprotein E ɛ4 allele is the primary genetic risk factor for the sporadic type of Alzheimer's disease. However, the mechanisms by which apolipoprotein E ɛ4 are associated with neurodegeneration are still poorly understood. We applied the Neurite Orientation Dispersion Model to characterize the effects of apolipoprotein ɛ4 and its interactions with age and education on cortical microstructure in cognitively normal individuals. Data from 1954 participants were included from the PREVENT-Dementia and ALFA (ALzheimer and FAmilies) studies (mean age = 57, 1197 non-carriers and 757 apolipoprotein E ɛ4 carriers). Structural MRI datasets were processed with FreeSurfer v7.2. The Microstructure Diffusion Toolbox was used to derive Orientation Dispersion Index maps from diffusion MRI datasets. Primary analyses were focused on (i) the main effects of apolipoprotein E ɛ4, and (ii) the interactions of apolipoprotein E ɛ4 with age and education on lobar and vertex-wise Orientation Dispersion Index and implemented using Permutation Analysis of Linear Models. There were apolipoprotein E ɛ4 × age interactions in the temporo-parietal and frontal lobes, indicating steeper age-dependent Orientation Dispersion Index changes in apolipoprotein E ɛ4 carriers. Steeper age-related Orientation Dispersion Index declines were observed among apolipoprotein E ɛ4 carriers with lower years of education. We demonstrated that apolipoprotein E ɛ4 worsened age-related Orientation Dispersion Index decreases in brain regions typically associated with atrophy patterns of Alzheimer's disease. This finding also suggests that apolipoprotein E ɛ4 may hasten the onset age of dementia by accelerating age-dependent reductions in cortical Orientation Dispersion Index.

6.
J Nutr Health Aging ; 28(1): 100007, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38267158

RESUMO

While the implementation of these initiatives varies globally and continues to face low uptake in the global south, it is crucial to underscore key ongoing efforts, particularly in developing nations. This allows us to have knowledge about progress and identify areas that require more effective strategies to advance the cause of global healthy aging. The aim of this mini-review was to describe some of the key age-friendly initiatives made in Mexico through Governmental and Non-Governmental entities to promote healthy aging, at different levels of health and social institutions, covering the healthcare systems, community, and education.


Assuntos
Envelhecimento Saudável , Humanos , México , Escolaridade
7.
Eur Geriatr Med ; 15(2): 527-537, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38168729

RESUMO

PURPOSE: Antipsychotic use in Alzheimer disease (AD) is associated with adverse events and mortality. Whilst postulated to cause/exacerbate orthostatic hypotension (OH), the exact relationship between antipsychotic use and OH has never been explored in AD-a group who are particularly vulnerable to neuro-cardiovascular instability and adverse effects of medication on orthostatic blood pressure (BP) behaviour. METHODS: We analysed longitudinal data from an 18-month trial of Nilvadipine in mild-moderate AD. We assessed the effect of long-term antipsychotic use (for the entire 18-month study duration) on orthostatic BP phenotypes measured on eight occasions, in addition to the relationship between antipsychotic use, BP phenotypes and incident falls. RESULTS: Of 509 older adults with AD (aged 72.9 ± 8.3 years, 61.9% female), 10.6% (n = 54) were prescribed a long-term antipsychotic. Over 18 months, long-term antipsychotic use was associated with a greater likelihood of experiencing sit-to-stand OH (ssOH) (OR: 1.21; 1.05-1.38, p = 0.009) which persisted on covariate adjustment. Following adjustment for important clinical confounders, both antipsychotic use (IRR: 1.80, 1.11-2.92, p = 0.018) and ssOH (IRR: 1.44, 1.00-2.06, p = 0.048) were associated with a greater risk of falls/syncope over 18 months in older adults with mild-moderate AD. CONCLUSION: Even in mild-to-moderate AD, long-term antipsychotic use was associated with ssOH. Both antipsychotic use and ssOH were associated with a greater risk of incident falls/syncope over 18 months. Further attention to optimal prescribing interventions in this cohort is warranted and may involve screening older adults with AD prescribed antipsychotics for both orthostatic symptoms and falls.


Assuntos
Doença de Alzheimer , Antipsicóticos , Hipotensão Ortostática , Idoso , Feminino , Humanos , Masculino , Acidentes por Quedas/prevenção & controle , Doença de Alzheimer/complicações , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/epidemiologia , Antipsicóticos/efeitos adversos , Hipotensão Ortostática/tratamento farmacológico , Hipotensão Ortostática/epidemiologia , Hipotensão Ortostática/complicações , Síncope/complicações , Idoso de 80 Anos ou mais
8.
Sci Rep ; 14(1): 573, 2024 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-38177228

RESUMO

To date, there is a considerable heterogeneity of methods to score Allostatic Load (AL). Here we propose a comprehensive algorithm (ALCS) that integrates commonly used approaches to generate AL risk categories and assess associations to brain structure deterioration. In a cohort of cognitively normal mid-life adults (n = 620, age 51.3 ± 5.48 years), we developed a comprehensive composite for AL scoring incorporating gender and age differences, high quartile approach, clinical reference values, and current medications, to then generate AL risk categories. Compared to the empirical approach (ALES), ALCS showed better model fit criteria and a strong association with age and sex. ALSC categories were regressed against brain and white matter hyperintensity (WMH) volumes. Higher AL risk categories were associated with increased total, periventricular, frontal, and left parietal WMH volumes, also showing better fit compared to ALES. When cardiovascular biomarkers were removed from the ALSC algorithm, only left-frontal WMHV remained associated with AL, revealing a strong vascular burden influencing the index. Our results agree with previous evidence and suggest that sustained stress exposure enhances brain deterioration in mid-life adults. Showing better fit than ALES, our comprehensive algorithm can provide a more accurate AL estimation to explore how stress exposure enhances age-related health decline.


Assuntos
Alostase , Substância Branca , Adulto , Humanos , Pessoa de Meia-Idade , Substância Branca/diagnóstico por imagem , Encéfalo , Imageamento por Ressonância Magnética
9.
Aging Ment Health ; : 1-7, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38192062

RESUMO

OBJECTIVES: The relationship between social isolation, loneliness, and tooth loss and cognition in older people is poorly understood. We examine how social isolation and cognitive performance are associated prospectively among older adults, as well as how tooth loss and loneliness are related to this association. METHODS: Using data from 26,168 participants aged ≥50 from the Survey of Health, Ageing and Retirement in Europe (SHARE), we explored the association between social isolation, loneliness, tooth loss and cognition. We used bootstrapping with resampling strategies for testing a moderated mediating model. RESULTS: Higher social isolation was associated with poorer cognitive performance (B = -0.20, 95% CI = -0.03, -0.01; R2 =0.60), an association mediated by the respondent's number of missing teeth (B = -0.001, 95% CI = -0.002, -0.001). Higher levels of social isolation were associated with a greater number of missing teeth, and a higher number of missing teeth was linked with poorer cognition. We also found that loneliness moderated the relationship between social isolation and both the number of missing teeth (B = -0.11, p = 0.047) and cognitive performance. CONCLUSION: In later life, social isolation and loneliness are associated with shoddy oral health and poor cognitive status. Clinicians and policymakers should be aware of both the association between social isolation and feelings of loneliness on dentition and oral health and their relationship to the cognitive status of older adults.

10.
Dement Neuropsychol ; 17: e20230016, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38089171

RESUMO

Primary Progressive Aphasia (PPA) is a progressive language disorder associated with frontotemporal impairment and mainly affects the left hemisphere of the brain. In general, this condition compromises abilities related to comprehension and expression of language. The diagnosis of PPA depends on in-depth knowledge regarding functions of language, neurology, and neuropsychology. Speech and language therapists (SLTs) have a pivotal role in the diagnosis and rehabilitation of PPA. The absence of these professionals involved in the diagnosis and rehabilitation may reflect on the quality of care of people with PPA. Objective: To identify the sociodemographic, educational, and professional practice characteristics of SLTs who work with people with PPA in Brazil. Methods: An online questionnaire was disseminated to reach SLTs across Brazil. The questionnaire collected information regarding sociodemographics, training and education, practice (time, setting, service provision), and sources of referral. Results: The study included 71 participants (95.8% women). Specialization was the most frequent educational level followed by master's degree, and participants where mainly from the Southeast and South regions of Brazil. Neurologists were the professionals who most referred patients with PPA to SLTs. Finally, SLTs worked primarily in homecare settings and provided mainly individual therapy services. Conclusion: SLTs who work with PPA in Brazil can be characterized mainly as professionals with postgraduate degrees, relatively young, and from the South and Southeast regions of Brazil.


A afasia progressiva primária (APP) é um distúrbio progressivo da linguagem associado à atrofia de regiões frontotemporais predominantemente do hemisfério esquerdo do cérebro. De modo geral, a APP afeta as capacidades compreensivas e expressivas da linguagem. O diagnóstico depende de profissionais com profundo conhecimento das funções da linguagem, neurologia e neuropsicologia. A fonoaudiologia tem papel essencial no diagnóstico e reabilitação da APP, e a ausência de fonoaudiólogos nesses processos pode refletir na qualidade do cuidado das pessoas com APP. Objetivo: Identificar as características sociodemográficas, educacionais e de atuação profissional de fonoaudiólogos que atuam com APP no Brasil. Métodos: Foi distribuído um questionário em formato online para fonoaudiólogos de todo o Brasil. O questionário coletou informações sobre aspectos sociodemográficos, de formação, atuação profissional (tempo, local de atuação, tipo de serviço oferecido) e fontes de encaminhamento. Resultados: O estudo incluiu 71 participantes (95,8% mulheres). O nível educacional mais frequente foi a especialização, e as regiões demográficas com maior incidência de profissionais que atendiam APP foram as Regiões Sudeste e Sul do país. Os neurologistas foram os profissionais que mais encaminhavam pacientes com APP para os fonoaudiólogos. Por fim, os fonoaudiólogos atuavam, principalmente, em homecare e realizando, em sua maioria, terapia individual. Conclusão: Os fonoaudiólogos que atuam com APP no Brasil podem ser caracterizados principalmente como profissionais pós-graduados, relativamente jovens e das Regiões Sul e Sudeste do Brasil.

11.
HRB Open Res ; 6: 12, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37954094

RESUMO

Background: Dementia research prioritisation allows for the systematic allocation of investment in dementia research by governments, funding agencies and the private sector. There is currently a lack of information available in Ireland regarding priority areas for dementia research. To address this gap, a dementia research prioritisation exercise was undertaken, consisting of an online survey of professionals in the dementia field and workshops for people living with dementia and family carers. Methods: (1) An anonymous online survey of professionals, based on an existing WHO global survey: the global survey was adapted to an Irish context and participants were asked to score 65 thematic research avenues under five criteria; (2) A mixed-methods exercise for people living with dementia and family carers: this involved two facilitated workshops where participants voted on the research themes they felt were important to them and should be addressed through research. Results: Eight of the top ten research priorities in the survey of professionals ( n=108) were focused on the delivery and quality of care and services for people with dementia and carers. Other research avenues ranked in the top ten focused on themes of timely and accurate diagnosis of dementia in primary health-care practices and diversifying therapeutic approaches in clinical trials. Participants in the workshops ( n=13) ranked 'better drugs and treatment for people with dementia', 'dementia prevention/ risk reduction' and 'care for people with dementia and carers' as their top priority areas. Conclusions: Findings from this prioritisation exercise will inform and motivate policymakers, funders and researchers to support and conduct dementia-focused research and ensure that the limited resources made available are spent on research that has the most impact for those who will benefit from and use the results of research.

13.
Neurobiol Aging ; 132: 233-245, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37866083

RESUMO

The underlying neural mechanisms underpinning the association between age-related hearing loss (ARHL) and dementia remain unclear. A limitation has been the lack of functional neuroimaging studies in ARHL cohorts to help clarify this relationship. In the present study, we investigated the neural correlates of feature binding in visual working memory with ARHL (controls = 14, mild HL = 21, and moderate or greater HL = 23). Participants completed a visual change detection task assessing feature binding while their neural activity was synchronously recorded via high-density electroencephalography. There was no difference in accuracy scores for ARHL groups compared to controls. There was increased electrophysiological activity in those with ARHL, particularly in components indexing the earlier stages of visual cognitive processing. This activity was more pronounced with more severe ARHL and was associated with maintained feature binding. Source space (sLORETA) analyses indicated greater activity in networks modulated by frontoparietal and temporal regions. Our results demonstrate there may be increased involvement of neurocognitive control networks to maintain lower-order neurocognitive processing disrupted by ARHL.


Assuntos
Memória de Curto Prazo , Presbiacusia , Humanos , Percepção Visual , Eletroencefalografia
14.
Am J Geriatr Psychiatry ; 31(12): 1017-1031, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37798224

RESUMO

This position statement of the Expert Panel on Brain Health of the American Association for Geriatric Psychiatry (AAGP) emphasizes the critical role of life course brain health in shaping mental well-being during the later stages of life. Evidence posits that maintaining optimal brain health earlier in life is crucial for preventing and managing brain aging-related disorders such as dementia/cognitive decline, depression, stroke, and anxiety. We advocate for a holistic approach that integrates medical, psychological, and social frameworks with culturally tailored interventions across the lifespan to promote brain health and overall mental well-being in aging adults across all communities. Furthermore, our statement underscores the significance of prevention, early detection, and intervention in identifying cognitive decline, mood changes, and related mental illness. Action should also be taken to understand and address the needs of communities that traditionally have unequal access to preventive health information and services. By implementing culturally relevant and tailored evidence-based practices and advancing research in geriatric psychiatry, behavioral neurology, and geroscience, we can enhance the quality of life for older adults facing the unique challenges of aging. This position statement emphasizes the intrinsic link between brain health and mental health in aging, urging healthcare professionals, policymakers, and a broader society to prioritize comprehensive strategies that safeguard and promote brain health from birth through later years across all communities. The AAGP Expert Panel has the goal of launching further activities in the coming months and years.


Assuntos
Saúde Mental , Qualidade de Vida , Humanos , Estados Unidos , Idoso , Psiquiatria Geriátrica , Acontecimentos que Mudam a Vida , Encéfalo
15.
Nat Med ; 29(9): 2248-2258, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37563242

RESUMO

Latin American populations may present patterns of sociodemographic, ethnic and cultural diversity that can defy current universal models of healthy aging. The potential combination of risk factors that influence aging across populations in Latin American and Caribbean (LAC) countries is unknown. Compared to other regions where classical factors such as age and sex drive healthy aging, higher disparity-related factors and between-country variability could influence healthy aging in LAC countries. We investigated the combined impact of social determinants of health (SDH), lifestyle factors, cardiometabolic factors, mental health symptoms and demographics (age, sex) on healthy aging (cognition and functional ability) across LAC countries with different levels of socioeconomic development using cross-sectional and longitudinal machine learning models (n = 44,394 participants). Risk factors associated with social and health disparities, including SDH (ß > 0.3), mental health (ß > 0.6) and cardiometabolic risks (ß > 0.22), significantly influenced healthy aging more than age and sex (with null or smaller effects: ß < 0.2). These heterogeneous patterns were more pronounced in low-income to middle-income LAC countries compared to high-income LAC countries (cross-sectional comparisons), and in an upper-income to middle-income LAC country, Costa Rica, compared to China, a non-upper-income to middle-income LAC country (longitudinal comparisons). These inequity-associated and region-specific patterns inform national risk assessments of healthy aging in LAC countries and regionally tailored public health interventions.


Assuntos
Doenças Cardiovasculares , Envelhecimento Saudável , Humanos , América Latina/epidemiologia , Estudos Transversais , Envelhecimento
16.
Front Psychol ; 14: 1214014, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37457094

RESUMO

Hope is a cognitive process by which an individual can identify their personal goals and develop actionable steps to achieve results. It has the potential to positively impact people's lives by building resilience, and can be meaningfully experienced at both the individual and group level. Despite this significance, there are sizable gaps in our understanding of the neurobiology of hope. In this perspective paper, the authors discuss why further research is needed on hope and its potency to be harnessed in society as a "tool" to promote brain health across healthy and patient populations. Avenues for future research in hope and the brain are proposed. The authors conclude by identifying strategies for the possible applications of hope in brain health promotion within the areas of technology, arts, media, and education.

18.
PLoS One ; 18(5): e0285529, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37167234

RESUMO

BACKGROUND: In addition to the clear cardiovascular benefit, there has been renewed interest in the potential of statins in the prevention of cognitive impairment and dementia in older adults. However, whether ongoing statin use can delay cognitive decline or dementia progression in those with established Alzheimer dementia, is unclear. METHODS: Using data from NILVAD, we analysed the association between ongoing statin use and cognitive decline (Alzheimer Disease Assessment Scale-Cognitive Subsection [ADAS-Cog])/dementia progression (Clinical Dementia Rating Scale [CDR-Sb]/Disability Assessment for Dementia [DAD]) over 18 months in older adults with mild-moderate AD. Additionally, we assessed the association between ongoing statin use and adverse events in mild-moderate AD. RESULTS: Over one-third (34.9%) of 510 older adults with mild-moderate AD (aged: 72.9 years; 61.9% female) used a statin for the 18-month study duration. Statin use was not associated with the rate of cognitive decline (ß: -0.67; 95% CI: -1.71, 0.36, p = 0.20) or dementia progression (ß: -0.34; 95% CI -0.71, 0.02; p = 0.07 for CDR-Sb/ ß: -2.00; -5.70, 1.70; p = 0.29 for DAD). Further, ongoing statin use was not associated with adverse events, serious adverse events, unscheduled GP visits, or unscheduled hospitalisation. CONCLUSION: Ongoing statin use was not associated with cognitive decline or dementia progression in mild-moderate AD. Similarly, use was not associated with adverse events including abnormal liver function tests or falls. Whilst safe in those with AD, the current results suggest ongoing statin use does not delay cognitive decline or clinical progression in established AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Inibidores de Hidroximetilglutaril-CoA Redutases , Feminino , Humanos , Idoso , Masculino , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/psicologia , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Disfunção Cognitiva/tratamento farmacológico , Estudos Longitudinais , Testes de Estado Mental e Demência , Progressão da Doença
19.
Neuroimage ; 276: 120200, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37245560

RESUMO

Anticipating social stress evokes strong reactions in the organism, including interoceptive modulations. However, evidence for this claim comes from behavioral studies, often with inconsistent results, and relates almost solely to the reactive and recovery phase of social stress exposure. Here, we adopted an allostatic-interoceptive predictive coding framework to study interoceptive and exteroceptive anticipatory brain responses using a social rejection task. We analyzed the heart-evoked potential (HEP) and task-related oscillatory activity of 58 adolescents via scalp EEG, and 385 human intracranial recordings of three patients with intractable epilepsy. We found that anticipatory interoceptive signals increased in the face of unexpected social outcomes, reflected in larger negative HEP modulations. Such signals emerged from key brain allostatic-interoceptive network hubs, as shown by intracranial recordings. Exteroceptive signals were characterized by early activity between 1-15 Hz across conditions, and modulated by the probabilistic anticipation of reward-related outcomes, observed over distributed brain regions. Our findings suggest that the anticipation of a social outcome is characterized by allostatic-interoceptive modulations that prepare the organism for possible rejection. These results inform our understanding of interoceptive processing and constrain neurobiological models of social stress.


Assuntos
Interocepção , Status Social , Adolescente , Humanos , Encéfalo/fisiologia , Potenciais Evocados/fisiologia , Eletroencefalografia , Coração , Interocepção/fisiologia
20.
J Cereb Blood Flow Metab ; 43(10): 1672-1684, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37132287

RESUMO

Cerebral hemodynamic alterations have been observed in apolipoprotein ε4 (APOE4) carriers at midlife, however the physiological underpinnings of this observation are poorly understood. Our goal was to investigate cerebral blood flow (CBF) and its spatial coefficient of variation (CoV) in relation to APOE4 and a measure of erythrocyte anisocytosis (red blood cell distribution width - RDW) in a middle-aged cohort. Data from 563 participants in the PREVENT-Dementia study scanned with 3 T MRI cross-sectionally were analysed. Voxel-wise and region-of-interest analyses within nine vascular regions were run to detect areas of altered perfusion. Within the vascular regions, interaction terms between APOE4 and RDW in predicting CBF were examined. Areas of hyperperfusion in APOE4 carriers were detected mainly in frontotemporal regions. The APOE4 allele differentially moderated the association between RDW and CBF, an association which was more prominent in the distal vascular territories (p - [0.01, 0.05]). The CoV was not different between the considered groups. We provide novel evidence that in midlife, RDW and CBF are differentially associated in APOE4 carriers and non-carriers. This association is consistent with a differential hemodynamic response to hematological alterations in APOE4 carriers.


Assuntos
Doença de Alzheimer , Apolipoproteína E4 , Circulação Cerebrovascular , Índices de Eritrócitos , Humanos , Pessoa de Meia-Idade , Fatores Etários , Doença de Alzheimer/genética , Apolipoproteína E4/genética , Circulação Cerebrovascular/genética , Índices de Eritrócitos/genética , Heterozigoto
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