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1.
Geroscience ; 46(4): 3929-3943, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38457007

RESUMO

Cognitive training using a visual speed-of-processing task, called the Useful Field of View (UFOV) task, reduced dementia risk and reduced decline in activities of daily living at a 10-year follow-up in older adults. However, there was variability in the achievement of cognitive gains after cognitive training across studies, suggesting moderating factors. Learning trials of visual and verbal learning tasks recruit similar cognitive abilities and have overlapping neural correlates with speed-of-processing/working memory tasks and therefore could serve as potential moderators of cognitive training gains. This study explored the association between the Hopkins Verbal Learning Test-Revised (HVLT-R) and Brief Visuospatial Memory Test-Revised (BVMT-R) learning with a commercial UFOV task called Double Decision. Through a secondary analysis of a clinical trial, we assessed the moderation of HVLT-R and BVMT-R learning on Double Decision improvement after a 3-month speed-of-processing/attention and working memory cognitive training intervention in a sample of 75 cognitively healthy older adults. Multiple linear regressions showed that better baseline Double Decision performance was significantly associated with better BVMT-R learning (ß = - .303). This association was not significant for HVLT-R learning (ß = - .142). Moderation analysis showed that those with poorer BVMT-R learning improved the most on the Double Decision task after cognitive training. This suggests that healthy older adults who perform below expectations on cognitive tasks related to the training task may show the greatest training gains. Future cognitive training research studying visual speed-of-processing interventions should account for differing levels of visuospatial learning at baseline, as this could impact the magnitude of training outcomes and efficacy of the intervention.


Assuntos
Memória de Curto Prazo , Humanos , Masculino , Feminino , Idoso , Memória de Curto Prazo/fisiologia , Testes de Memória e Aprendizagem , Tomada de Decisões/fisiologia , Cognição/fisiologia , Testes Neuropsicológicos , Idoso de 80 Anos ou mais , Treino Cognitivo
2.
Geroscience ; 46(3): 3325-3339, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38265579

RESUMO

Declines in several cognitive domains, most notably processing speed, occur in non-pathological aging. Given the exponential growth of the older adult population, declines in cognition serve as a significant public health issue that must be addressed. Promising studies have shown that cognitive training in older adults, particularly using the useful field of view (UFOV) paradigm, can improve cognition with moderate to large effect sizes. Additionally, meta-analyses have found that transcranial direct current stimulation (tDCS), a non-invasive form of brain stimulation, can improve cognition in attention/processing speed and working memory. However, only a handful of studies have looked at concomitant tDCS and cognitive training, usually with short interventions and small sample sizes. The current study assessed the effect of a tDCS (active versus sham) and a 3-month cognitive training intervention on task-based functional connectivity during completion of the UFOV task in a large older adult sample (N = 153). We found significant increased functional connectivity between the left and right pars triangularis (the ROIs closest to the electrodes) following active, but not sham tDCS. Additionally, we see trending behavioral improvements associated with these functional connectivity changes in the active tDCS group, but not sham. Collectively, these findings suggest that tDCS and cognitive training can be an effective modulator of task-based functional connectivity above and beyond a cognitive training intervention alone.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Humanos , Idoso , Treino Cognitivo , Cognição/fisiologia , Memória de Curto Prazo/fisiologia , Córtex Pré-Frontal
3.
Geroscience ; 45(5): 3079-3093, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37814198

RESUMO

Limited research exists on the association between resting-state functional network connectivity in the brain and learning and memory processes in advanced age. This study examined within-network connectivity of cingulo-opercular (CON), frontoparietal control (FPCN), and default mode (DMN) networks, and verbal and visuospatial learning and memory in older adults. Across domains, we hypothesized that greater CON and FPCN connectivity would associate with better learning, and greater DMN connectivity would associate with better memory. A total of 330 healthy older adults (age range = 65-89) underwent resting-state fMRI and completed the Hopkins Verbal Learning Test-Revised (HVLT-R) and Brief Visuospatial Memory Test-Revised (BVMT-R) in a randomized clinical trial. Total and delayed recall scores were assessed from baseline data, and a learning ratio calculation was applied to participants' scores. Average CON, FPCN, and DMN connectivity values were obtained with CONN Toolbox. Hierarchical regressions controlled for sex, race, ethnicity, years of education, and scanner site, as this was a multi-site study. Greater within-network CON connectivity was associated with better verbal learning (HVLT-R Total Recall, Learning Ratio), visuospatial learning (BVMT-R Total Recall), and visuospatial memory (BVMT-R Delayed Recall). Greater FPCN connectivity was associated with better visuospatial learning (BVMT-R Learning Ratio) but did not survive multiple comparison correction. DMN connectivity was not associated with these measures of learning and memory. CON may make small but unique contributions to learning and memory across domains, making it a valuable target in future longitudinal studies and interventions to attenuate memory decline. Further research is necessary to understand the role of FPCN in learning and memory.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Humanos , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Memória , Aprendizagem , Rememoração Mental
4.
Geroscience ; 45(1): 293-309, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35948860

RESUMO

Declines in processing speed performance occur in aging and are a critical marker of functional independence in older adults. Numerous studies suggest that Useful Field of View (UFOV) training may ameliorate cognitive decline in older adults. Despite its efficacy, little is known about the neural correlates of this task. The current study is the first to investigate the coherence of functional connectivity during UFOV task completion. A total of 336 participants completed the UFOV task while undergoing task-based functional magnetic resonance imaging (fMRI). Ten spherical regions of interest (ROIs), selected a priori, were created based on regions with the greatest peak BOLD activation patterns in the UFOV fMRI task and regions that have been shown to significantly relate to UFOV fMRI task performance. We used a weighted ROI-to-ROI connectivity analysis to model task-specific functional connectivity strength between these a priori selected ROIs. We found that our UFOV fMRI network was functionally connected during task performance and was significantly associated to UFOV fMRI task performance. Within-network connectivity of the UFOV fMRI network showed comparable or better predictive power in accounting for UFOV accuracy compared to 7 resting state networks, delineated by Yeo and colleagues. Finally, we demonstrate that the within-network connectivity of UFOV fMRI task accounted for scores on a measure of "near transfer", the Double Decision task, better than the aforementioned resting state networks. Our data elucidate functional connectivity patterns of the UFOV fMRI task. This may assist in future targeted interventions that aim to improve synchronicity within the UFOV fMRI network.


Assuntos
Disfunção Cognitiva , Imageamento por Ressonância Magnética , Humanos , Idoso , Imageamento por Ressonância Magnética/métodos , Envelhecimento/fisiologia , Análise e Desempenho de Tarefas
5.
Geroscience ; 44(3): 1441-1455, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35278154

RESUMO

Cognitive training has shown promise for improving cognition in older adults. Age-related neuroanatomical changes may affect cognitive training outcomes. White matter hyperintensities are one common brain change in aging reflecting decreased white matter integrity. The current study assessed (1) proximal cognitive training performance following a 3-month randomized control trial and (2) the contribution of baseline whole-brain white matter hyperintensity load, or total lesion volume (TLV), on pre-post proximal training change. Sixty-two healthy older adults were randomized to either adaptive cognitive training or educational training control interventions. Repeated-measures analysis of covariance revealed two-way group × time interactions such that those assigned cognitive training demonstrated greater improvement on proximal composite (total training composite) and sub-composite (processing speed training composite, working memory training composite) measures compared to education training counterparts. Multiple linear regression showed higher baseline TLV associated with lower pre-post change on processing speed training sub-composite (ß = -0.19, p = 0.04), but not other composite measures. These findings demonstrate the utility of cognitive training for improving post-intervention proximal performance in older adults. Additionally, pre-post proximal processing speed training change appears to be particularly sensitive to white matter hyperintensity load versus working memory training change. These data suggest that TLV may serve as an important factor for consideration when planning processing speed-based cognitive training interventions for remediation of cognitive decline in older adults.


Assuntos
Transtornos Cognitivos , Disfunção Cognitiva , Substância Branca , Idoso , Encéfalo/patologia , Cognição , Disfunção Cognitiva/patologia , Humanos
6.
Geroscience ; 44(2): 1011-1027, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35258771

RESUMO

Prior randomized control trials have shown that cognitive training interventions resulted in improved proximal task performance, improved functioning of activities of daily living, and reduced dementia risk in healthy older adults. Neural correlates implicated in cognitive training include hub brain regions of higher-order resting state networks including the default mode network, dorsal attention network, frontoparietal control network, and cingulo-opercular network. However, little is known about resting state network change after cognitive training, or the relation between functional brain changes and improvement in proximal task performance. We assessed the 1) change in proximal task performance, 2) change in higher-order resting state network connectivity via functional magnetic resonance imaging, and 3) association between these variables after a multidomain attention/speed-of-processing and working memory randomized control trial in a sample of 58 healthy older adults. Participants in the cognitive training group improved significantly on seven out of eight training tasks immediately after the training intervention with the largest magnitude of improvement in a divided attention/speed-of-processing task, the Double Decision task. Only the frontoparietal control network had significantly strengthened connectivity in the cognitive training group at the post-intervention timepoint. Lastly, higher frontoparietal control network connectivity was associated with improved Double Decision task performance after training in the cognitive training group. These findings show that the frontoparietal control network may strengthen after multidomain cognitive training interventions, and this network may underlie improvements in divided attention/speed-of-processing proximal improvement.


Assuntos
Atividades Cotidianas , Cognição , Idoso , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Vias Neurais
7.
Neuroimage Rep ; 2(2)2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37377763

RESUMO

Minimizing head motion during functional magnetic resonance imaging (fMRI) is important for maintaining the integrity of neuroimaging data. While there are a variety of techniques to control for head motion, oftentimes, individuals with excessive in-scanner motion are removed from analyses. Movement in the scanner tends to increase with age; however, the cognitive profile of these "high-movers" in older adults has yet to be explored. This study aimed to assess the association between in-scanner head motion (i.e., number of "invalid scans" flagged as motion outliers) and cognitive functioning (e.g., executive functioning, processing speed, and verbal memory performance) in a sample of 282 healthy older adults. Spearman's Rank-Order correlations showed that a higher number of invalid scans was significantly associated with poorer performance on tasks of inhibition and cognitive flexibility and with older age. Since performance in these domains tend to decline as a part of the non-pathological aging process, these findings raise concerns regarding the potential systematic exclusion due to motion of older adults with lower executive functioning in neuroimaging samples. Future research should continue to explore prospective motion correction techniques to better ensure the collection of quality neuroimaging data without excluding informative participants from the sample.

8.
Cereb Cortex ; 32(9): 1993-2012, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-34541604

RESUMO

Declines in processing speed performance occur in aging and are a critical marker of functional independence in older adults. Studies suggest that Useful Field of View (UFOV) training may ameliorate cognitive decline. Despite its efficacy, little is known about the neural correlates of this task. Within the current study, 233 healthy older adults completed a UFOV-based task while undergoing functional magnetic resonance imaging (fMRI). During the "stimulus" portion of this task, participants must identify a target in the center of the screen and the location of a target in the periphery, among distractors. During the "probe" portion, participants must decide if the object in the center and the location of the target in the periphery were identical to the "stimulus" screen. Widespread bilateral whole-brain activation was observed when activation patterns of the "probe" contrast were subtracted from the "stimulus" contrast. Conversely, the subtraction of "stimulus" from "probe" was associated with discrete activation patterns consisting of 13 clusters. Additionally, when evaluating the variance associated with task accuracy, specific subregions were identified that may be critical for task performance. Our data elucidate the functional neural correlates of a UFOV-based task, a task used in both cognitive training paradigms and assessment of function.


Assuntos
Cognição , Imageamento por Ressonância Magnética , Idoso , Envelhecimento/fisiologia , Encéfalo/diagnóstico por imagem , Cognição/fisiologia , Humanos , Análise e Desempenho de Tarefas
9.
Geroscience ; 44(1): 131-145, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34431043

RESUMO

Speed-of-processing abilities decline with age yet are important in performing instrumental activities of daily living. The useful field of view, or Double Decision task, assesses speed-of-processing and divided attention. Performance on this task is related to attention, executive functioning, and visual processing abilities in older adults, and poorer performance predicts more motor vehicle accidents in the elderly. Cognitive training in this task reduces risk of dementia. Structural and functional neural correlates of this task suggest that higher-order resting state networks may be associated with performance on the Double Decision task, although this has never been explored. This study aimed to assess the association of within-network connectivity of the default mode network, dorsal attention network, frontoparietal control network, and cingulo-opercular network with Double Decision task performance, and subcomponents of this task in a sample of 267 healthy older adults. Multiple linear regressions showed that connectivity of the cingulo-opercular network is associated with visual speed-of-processing and divided attention subcomponents of the Double Decision task. Cingulo-opercular network and frontoparietal control network connectivity is associated with Double Decision task performance. Stronger connectivity is related to better performance in all cases. These findings confirm the unique role of the cingulo-opercular network in visual attention and sustained divided attention. Frontoparietal control network connectivity, in addition to cingulo-opercular network connectivity, is related to Double Decision task performance, a task implicated in reduced dementia risk. Future research should explore the role these higher-order networks play in reduced dementia risk after cognitive intervention using the Double Decision task.


Assuntos
Atividades Cotidianas , Imageamento por Ressonância Magnética , Idoso , Cognição , Humanos , Vias Neurais , Percepção Visual
10.
Geroscience ; 44(2): 847-866, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34950997

RESUMO

Executive function is a cognitive domain that typically declines in non-pathological aging. Two cognitive control networks that are vulnerable to aging-the cingulo-opercular (CON) and fronto-parietal control (FPCN) networks-play a role in various aspects of executive functioning. However, it is unclear how communication within these networks at rest relates to executive function subcomponents in older adults. This study examines the associations between CON and FPCN connectivity and executive function performance in 274 older adults across working memory, inhibition, and set-shifting tasks. Average CON connectivity was associated with better working memory, inhibition, and set-shifting performance, while average FPCN connectivity was associated solely with working memory. CON region of interest analyses revealed significant connections with classical hub regions (i.e., anterior cingulate and anterior insula) for each task, language regions for verbal working memory, right hemisphere dominance for inhibitory control, and widespread network connections for set-shifting. FPCN region of interest analyses revealed largely right hemisphere fronto-parietal connections important for working memory and a few temporal lobe connections for set-shifting. These findings characterize differential brain-behavior relationships between cognitive control networks and executive function in aging. Future research should target these networks for intervention to potentially attenuate executive function decline in older adults.


Assuntos
Mapeamento Encefálico , Função Executiva , Encéfalo , Função Executiva/fisiologia , Imageamento por Ressonância Magnética , Memória de Curto Prazo
11.
Neuropsychiatr Dis Treat ; 17: 971-990, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33824591

RESUMO

BACKGROUND: Transcranial direct current stimulation (tDCS) has been proposed as a possible method for remediating age-associated cognitive decline in the older adult population. While tDCS has shown potential for improving cognitive functions in healthy older adults, stimulation outcomes on various cognitive domains have been mixed. METHODS: A systematic search was performed in four databases: PubMed, EMBASE, Web of Science, and PsychInfo. Search results were then screened for eligibility based on inclusion/exclusion criteria to only include studies where tDCS was applied to improve cognition in healthy older adults 65 years and above. Eligible studies were reviewed and demographic characteristics, tDCS dose parameters, study procedures, and cognitive outcomes were extracted. Reported effect sizes for active compared to sham group in representative cognitive domain were converted to Hedges' g. MAIN RESULTS: A total of thirteen studies involving healthy older adults (n=532, mean age=71.2+5.3 years) were included in the meta-analysis. The majority of included studies (94%) targeted the prefrontal cortex with stimulation intensity 1-2 mA using various electrode placements with anodes near the frontal region. Across all studies, we found Hedges' g values ranged from -0.31 to 1.85 as reported group effect sizes of active stimulation compared to sham. CONCLUSION: While observed outcomes varied, overall findings indicated promising effects of tDCS to remediate cognitive aging and thus deserves further exploration. Future characterization of inter-individual variability in tDCS dose response and applications in larger cohorts are warranted to further validate benefits of tDCS for cognition in healthy older adults.

12.
J Neuropsychol ; 15(2): 253-273, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33029951

RESUMO

Despite the life-extending success of antiretroviral pharmacotherapy in HIV infection (HIV), the prevalence of mild cognitive impairment in HIV remains high. Near-normal life expectancy invokes an emerging role for age-infection interaction and a potential synergy between immunosenescence and HIV-related health factors, increasing risk of cognitive and motor impairment associated with degradation in corticostriatal circuits. These neural systems are also compromised in Parkinson's disease (PD), which could help model the cognitive deficit pattern in HIV. This cross-sectional study examined three groups, age 45-79 years: 42 HIV, 41 PD, and 37 control (CTRL) participants, tested at Stanford University Medical School and SRI International. Neuropsychological tests assessed executive function (EF), information processing speed (IPS), episodic memory (MEM), visuospatial processing (VSP), and upper motor (MOT) speed and dexterity. The HIV and PD deficit profiles were similar for EF, MEM, and VSP. Although only the PD group was impaired on MOT compared with CTRL, MOT scores were related to cognitive scores in HIV but not PD. Performance was not related to depressive symptoms, socioeconomic status, or CD4+ T-cell counts. The overlap of HIV-PD cognitive deficits implicates frontostriatal disruption in both conditions. The motor-cognitive score relation in HIV provides further support for the hypothesis that these processes share similar underlying mechanisms in HIV infection possibly expressed with or exacerbated by ageing.


Assuntos
Disfunção Cognitiva , Infecções por HIV , Doença de Parkinson , Idoso , Envelhecimento , Cognição , Disfunção Cognitiva/complicações , Estudos Transversais , Função Executiva , Infecções por HIV/complicações , Humanos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Doença de Parkinson/complicações
13.
Cereb Cortex ; 31(3): 1732-1743, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33188384

RESUMO

Age-related differences in dorsolateral prefrontal cortex (DLPFC) structure and function have each been linked to working memory. However, few studies have integrated multimodal imaging to simultaneously investigate relationships among structure, function, and cognition. We aimed to clarify how specifically DLPFC structure and function contribute to working memory in healthy older adults. In total, 138 participants aged 65-88 underwent 3 T neuroimaging and were divided into higher and lower groups based on a median split of in-scanner n-back task performance. Three a priori spherical DLPFC regions of interest (ROIs) were used to quantify blood-oxygen-level-dependent (BOLD) signal and FreeSurfer-derived surface area, cortical thickness, and white matter volume. Binary logistic regressions adjusting for age, sex, education, and scanner type revealed that greater left and right DLPFC BOLD signal predicted the probability of higher performing group membership (P values<.05). Binary logistic regressions also adjusting for total intracranial volume revealed left DLPFC surface area that significantly predicted the probability of being in the higher performing group (P = 0.017). The left DLPFC BOLD signal and surface area were not significantly associated and did not significantly interact to predict group membership (P values>.05). Importantly, this suggests BOLD signal and surface area may independently contribute to working memory performance in healthy older adults.


Assuntos
Córtex Pré-Frontal Dorsolateral/fisiologia , Memória de Curto Prazo/fisiologia , Idoso , Idoso de 80 Anos ou mais , Mapeamento Encefálico/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino
14.
Front Aging Neurosci ; 12: 593833, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33250765

RESUMO

Objective: The association between hippocampal volume and memory is continuing to be characterized in healthy older adults. Prior research suggests smaller hippocampal volume in healthy older adults is associated with poorer episodic memory and processing speed, as well as working memory, verbal learning, and executive functioning as measured by the NIH Toolbox Fluid (Fluid Cognition Composite, FCC) and Crystalized Cognition Composites (CCC). This study aimed to replicate these findings and to evaluate the association between: (1) hippocampal asymmetry index and cognition; and (2) independent contributions of the left and right hippocampal volume and cognition in a large sample of healthy older adults. Participants and Methods: One-hundred and eighty-three healthy older adults (M age = 71.72, SD = 5.3) received a T1-weighted sequence on a 3T scanner. Hippocampal subfields were extracted using FreeSurfer 6.0 and combined to provide left, right, and total hippocampal volumes. FCC subtests include Dimensional Change Card Sort, Flanker Inhibitory Control and Attention, List Sorting, Picture Sequence Memory, and Pattern Comparison. CCC subtests include Picture Vocabulary and Oral Reading Recognition. Multiple linear regressions were performed predicting cognition composites from the total, left and right, and asymmetry of hippocampal volume, controlling for sex, education, scanner, and total intracranial volume. Multiple comparisons in primary analyses were corrected using a false discovery rate (FDR) of p < 0.05. Results: FCC scores were positively associated with total (ß = 0.226, FDR q = 0.044) and left (ß = 0.257, FDR q = 0.024) hippocampal volume. Within FCC, Picture Sequence Memory scores positively associated with total (ß = 0.284, p = 0.001) and left (ß = 0.98, p = 0.001) hippocampal volume. List Sorting scores were also positively associated with left hippocampal volume (ß = 0.189, p = 0.029). Conclusions: These results confirm previous research suggesting that bilateral hippocampal volume is associated with FCC, namely episodic memory. The present study also suggests the left hippocampal volume may be more broadly associated with both episodic and working memory. Studies should continue to investigate lateralized hippocampal contributions to aging processes to better identify predictors of cognitive decline.

15.
Front Aging Neurosci ; 11: 117, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31156423

RESUMO

For adults age 65 and older, the brain shows acute functional connectivity decreases after total knee arthroplasty with the severity of change predicted by preoperative cognitive function and brain disease burden. The extent of acute structural microstructural brain changes acutely after surgery remains unknown within the literature. For the current study, we report on the severity of acute post-surgery microstructural brain changes as measured by diffusion imaging and free-water analysis. Participants who underwent total knee arthroplasty under general anesthesia and non-surgery peers were part of a federally funded prospective cohort investigation involving participants. Recruitment occurred between 2013 and 2017. Data were collected in outpatient and inpatient settings within a university-affiliated medical center. A total of 232 TKA patients were referred by the study surgeon and contacted for study inclusion. Of these, 78 met inclusion and exclusion criteria and completed assessment. Five participants were excluded due to anesthetic protocol changes (spinal instead of general) with an additional 12 excluded for imaging-related complications. The total included sample size was 61. A total of 127 non-surgery participants were screened with 66 enrolled. One non-surgery participant was excluded for an imaging-related complication. Total knee arthroplasty and general anesthetic protocols were standardized. Participants received preoperative neurocognitive assessment and brain magnetic resonance imaging, with repeat imaging 48 h after surgery or pseudo surgery. Free-water analyses were performed using diffusion weighted images and tract-based spatial statistics with baseline cognitive data used to predict free-water changes. Surgery participants had widespread increases in white matter free-water. Surgery participants with higher cognitive functions as measured by immediate memory and less evidence of brain atrophy and disease (i.e., brain integrity) had greater free-water increase. Non-surgery peers had no free-water change. We interpret the surgery group's free-water change as indicating widespread brain white matter glial response, with greater change indicative of better brain response to the acute surgery/anesthesia experience.

16.
J Alzheimers Dis ; 69(4): 1003-1018, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31104019

RESUMO

BACKGROUND: Research shows that older adults can have a decline in three key resting state networks (default mode network, central executive network, and salience network) after total knee arthroplasty and that patients' pre-surgery brain and cognitive integrity predicts decline. OBJECTIVES: First, to assess resting state network connectivity decline from the perspective of nodal connectivity changes in a larger older adult surgery sample. Second, to compare pre-post functional connectivity changes in mild cognitive impairment (MCI) versus non-MCI. METHODS: Surgery (n = 69) and non-surgery (n = 65) peers completed a comprehensive preoperative neuropsychological evaluation and pre- and acute (within 48 hours) post-surgery/pseudo-surgery functional brain magnetic resonance imaging scan. MCI was classified within both (MCI surgery, n = 13; MCI non-surgery, n = 10). Using standard coordinates, we defined default mode network, salience network, central executive network, and the visual network (serving as a control network). The functional connectivity of these networks and brain areas (nodes) that make up these networks were examined for pre-post-surgery changes through paired samples t-test and ANOVA. RESULTS: There was a decline in RSN connectivity after surgery (p < 0.05) only in the three cognitive networks (not the visual network). The default mode and salience network showed nodal connectivity changes (p < 0.01). MCI surgery had greater functional connectivity decline in DMN and SN. Non-surgery participants showed no significant functional connectivity change. CONCLUSION: Surgery with general anesthesia selectively alters functional connectivity in major cognitive resting state networks particularly in DMN and SN. Participants with MCI appear more vulnerable to these functional changes.


Assuntos
Anestesia Geral/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Disfunção Cognitiva/etiologia , Rede Nervosa/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Estudos de Casos e Controles , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Neuroimagem
17.
Addict Biol ; 24(2): 290-302, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29243370

RESUMO

Variations in pattern and extent of cognitive and motor impairment occur in alcoholism (ALC). Causes of such heterogeneity are elusive and inconsistently accounted for by demographic or alcohol consumption differences. We examined neurological and nutritional factors as possible contributors to heterogeneity in impairment. Participants with ALC (n = 96) and a normal comparison group (n = 41) were examined on six cognitive and motor domains. Signs of historically determined subclinical Wernicke's encephalopathy were detected using the Caine et al. criteria, which were based on postmortem examination and chart review of antemortem data of alcoholic cases with postmortem evidence for Wernicke's encephalopathy. Herein, four Caine criteria provided quantification of dietary deficiency, cerebellar dysfunction, low general cognitive functioning and oculomotor abnormalities in 86 of the 96 ALC participants. Subgroups based on Caine criteria yielded a graded effect, where those meeting more criteria exhibited greater impairment than those meeting no to fewer criteria. These results could not be accounted for by history of drug dependence. Multiple regression indicated that compromised performance on ataxia, indicative of cerebellar dysfunction, predicted non-mnemonic and upper motor deficits, whereas low whole blood thiamine level, consistent with limbic circuit dysfunction, predicted mnemonic deficits. This double dissociation indicates biological markers that contribute to heterogeneity in expression of functional impairment in ALC. That non-mnemonic and mnemonic deficits are subserved by the dissociable neural systems of frontocerebellar and limbic circuitry, both commonly disrupted in ALC, suggests neural mechanisms that can differentially affect selective functions, thereby contributing to heterogeneity in pattern and extent of dysfunction in ALC.


Assuntos
Alcoolismo/complicações , Transtornos Cognitivos/etiologia , Comportamento Alimentar/fisiologia , Transtornos Motores/etiologia , Encefalopatia de Wernicke/complicações , Adolescente , Adulto , Criança , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
18.
J HIV AIDS Infect Dis ; 4(1)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38481564

RESUMO

Background: Childhood trauma carries heightened risk for neuropsychological impairment and is a frequent concomitant of HIV infection (H) and alcoholism (Alc). Little is known about compounded effects of childhood trauma and these diseases on cognitive and motor functioning. We queried the relation between childhood trauma history (experiencing at least 1 of 13 specified traumas before age 18) and cognitive and motor performance in HIV infection with and without lifetime alcoholism. Methods: Relations between childhood trauma history (Tr) and four performance domains (episodic memory, information processing speed, executive function, and fine motor function) were examined via ANCOVAs covarying for age and education in four HIV groups: 21 H+Alc+Tr, 19 H+Alc, 19 H+Tr, and 25 HComp (H comparison group without Tr or Alc). Results: H+Tr, irrespective of Alc, performed poorly on the episodic memory domain. Specifically, immediate and delayed verbal recall, and immediate visual recall were affected in those with HIV and history of childhood trauma with or without alcoholism history. By contrast, H+Alc+Tr performed faster than H+Alc or H+Tr in information processing speed. Conclusion: The findings of poorer episodic memory in HIV infection with childhood trauma history corroborates previous reports and now extends findings to H+Alc+Tr trimorbidity. The novel interaction of alcoholism and trauma in HIV infection suggests that information processing speed is slowed with trauma history or alcoholism history alone in HIV but not with HIV+Alc+Tr trimorbidity, possibly reflecting greater impulsivity and hyperarousal in multiply-affected individuals.

19.
Behav Brain Sci ; 39: e180, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28355804

RESUMO

Passive frame theory is compatible with modern complexity theory and the idea that conflict drives the emergence of a novel structural organization. After describing new developmental data, we suggest that this conflict needs to be expanded to include not only conflict between action options, but also between action and perception.


Assuntos
Desenvolvimento Infantil , Impulso (Psicologia) , Criança , Humanos , Modelos Teóricos , Percepção
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