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2.
Epilepsy Behav ; 140: 109088, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36702057

RESUMO

Clinicians have an ethical obligation to obtain and convey relevant information about possible treatment outcomes in a manner that can be comprehended by patients. This contributes to the processes of informed consent and shared prospective decision-making. In epilepsy neurosurgery, there has historically been an emphasis on studying clinician-centered (e.g., seizure- and cognition-related) outcomes and using these data to inform recommendations and, by extension, to frame pre-surgical counseling with respect to patients' decisions about elective neurosurgery. In contrast, there is a relative dearth of available data related to patient-centered outcomes of epilepsy neurosurgery, such as functional (e.g., employment) status, and there is also a lack of methods to communicate these data to patients. Here, illustrated using a hypothetical case scenario, we present a potential solution to the latter of these problems using principles of evidence-based neuropsychology; published data on patient employment status before and after epilepsy neurosurgery; and Bayes' theorem. First, we reviewed existing literature on employment outcomes following epilepsy neurosurgery to identify and extract data relevant to our hypothetical patient, clinical question, and setting. Then, we used the base rate (prior probability) of post-surgical unemployment, contingency tables (to derive likelihood ratios), and Bayes' theorem to compute the conditional (posterior) probability of post-surgical employment status for our hypothetical patient scenario. Finally, we translated this information to an intuitive visual format (Bayesian nomogram) that can support evidence-based pre-surgical counseling. We propose that the application of our patient-centered decision-support process and visual aid will improve clinician-patient communication about prospective risks and benefits of epilepsy neurosurgery and will empower clinicians and patients to make informed decisions about whether or not to pursue elective neurosurgery with a greater degree of confidence and with more realistic and concrete expectations about possible outcomes. We further propose that clinicians and patients would benefit from incorporating this evidence-based framework into a broader sequence of function-focused epilepsy treatment that includes pre-surgical assessments and interventions ("prehabilitation"), neurosurgery, and post-surgical cognitive/vocational rehabilitation.


Assuntos
Epilepsia , Nomogramas , Humanos , Teorema de Bayes , Probabilidade , Epilepsia/diagnóstico , Epilepsia/cirurgia , Assistência Centrada no Paciente
3.
Clin Neuropsychol ; 34(4): 643-677, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32052696

RESUMO

Objective: Ethical and economic values compel us to improve the screening, monitoring, and enhancement of older adult neurocognitive adaptability. Diverse contemporary theoretical and empirical perspectives highlight the multi-timescale, multi-mechanistic nature of neurocognitive adaptability. Still lacking are frameworks and methodologies that demonstrate this convergence to allow for new paradigms that harness the clinical utility of neurocognitive adaptability.Method: We present a multi-method, multi-timescale analysis of neurocognitive adaptability in a group of healthy, community-dwelling older adults from the Victoria, British Columbia region. Each participant completed a 96-trial computerized cognitive flexibility task at 4 to 6 separate laboratory visits spanning about a month. This captured within-person changes at the within-occasion and across-occasion levels (timescales of seconds and days/weeks, respectively). We used standardized clinical assessments of cognitive reserve (i.e., estimated premorbid function) and conscientiousness (a personality dimension) as cross-sectional (time-invariant) predictors in multi-level linear regression to illustrate between-person differences in within-person cognitive performance trajectories.Results: Reserve predicted cognitive performance differences at the timescale of seconds (within occasions) but did not relate to differences at the timescale of days/weeks (across occasions); in contrast, conscientiousness predicted cognitive performance differences at both timescales. Distinct processes operating within the same task (stimulus-classification vs. set-shifting) improved with practice at discrepant rates.Conclusions: Neurocognitive adaptability is underlain by multiple biopsychosocial mechanisms. Certain widely-used clinical indices (e.g., of reserve or conscientiousness) may estimate distinct types of neurocognitive adaptability relevant to maintaining functional independence into old age. Our methodology and theoretical framework assume that neurocognitive adaptability unfolds at multiple hierarchical scales of time.


Assuntos
Transtornos Neurocognitivos/diagnóstico , Testes Neuropsicológicos/normas , Idoso , Estudos Transversais , Feminino , Humanos , Masculino
4.
Clin Neuropsychol ; 33(2): 390-418, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30648474

RESUMO

OBJECTIVE: This study was undertaken to explore multimethod neurocognitive screening tools to aid in detection of older adults who may be at heightened risk of pathological cognitive decline (preclinical dementia). In so doing, this study advances the theoretical conceptualization of neurocognitive adaptability in the context of aging and dementia. METHOD: This article reports original data from the baseline measurement occasion of a longitudinal study of healthy, community-dwelling older adults from the Victoria, British Columbia region. Participants were diagnosed as normal, subtle decline, or mild cognitive impairment according to actuarial neuropsychological criteria (adjusted for age only or adjusted for age and premorbid IQ). Diagnostic classification was employed to illustrate group differences in a novel metric of multi-timescale neural adaptability derived from 4-min of resting-state electroencephalographic data collected from each participant (immediately following their neuropsychological evaluation). RESULTS: Prior findings were replicated; adjusting raw neuropsychological test scores for individual differences in estimated premorbid IQ appeared to increase the sensitivity of standardized clinical tasks to subtle cognitive impairment. Moreover, and consistent with prior neuroscientific research, timescale-specific (i.e. at ∼12-20 ms timescales) differences in resting-state neural adaptability appeared to characterize groups who differed in terms of neuropsycholgoical diagnostic classification. CONCLUSIONS: Recently proposed actuarial neuropsychological criteria for subtle cognitive decline identify older adults who show timescale-specific changes in resting brain function that may signal the onset of preclinical dementia. The subtle decline stage may represent a critical inflection point-partial loss of neurocognitive adaptability-on a pathological aging trajectory. These findings illustrate areas of potential future development in neurocognitive health care.


Assuntos
Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/psicologia , Eletroencefalografia/métodos , Eletroencefalografia/psicologia , Testes Neuropsicológicos , Descanso/psicologia , Adaptação Psicológica/fisiologia , Idoso , Idoso de 80 Anos ou mais , Disfunção Cognitiva/fisiopatologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Estudos Prospectivos , Descanso/fisiologia
5.
Child Neuropsychol ; 24(5): 617-637, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28301980

RESUMO

Intra-individual variability (IIV) is defined as systematic within-person variation in performance either across test sessions (e.g., test/retest performance on the same task) or in one session (e.g., variations in performance on multiple trials of a single task). Higher levels of IIV have been noted as a characteristic of neurodevelopmental disorders such as attention deficit/hyperactivity disorder​ (ADHD), but IIV is yet to be investigated in fetal alcohol spectrum disorder (FASD). FASD is a term used to describe a range of conditions resulting from prenatal exposure to alcohol. As part of a comprehensive neuropsychological battery, four study groups (1. fetal alcohol syndrome/partial fetal alcohol syndrome; 2. static encephalopathy/alcohol exposed; 3. neurobehavioral disorder/alcohol exposed as diagnosed using the University of Washington FASD 4-Digit Code; 4. typically-developing (TD) age-matched children with no prenatal alcohol exposure) were administered measures of motor response and inhibitory control, attention, and adaptive behavior. The results indicate increased levels of IIV in those with FASD compared to the TD controls. It was found that IIV uniquely contributes to predicting adaptive behavior above and beyond attention, while attention partially mediates the relationship between IIV and adaptive behavior. This is the first study to the authors' knowledge to show the presence of increased IIV in children with FASD. It additionally provides evidence that IIV measures some inherent variability in performance independent of poor attention in children with FASD.


Assuntos
Transtornos do Espectro Alcoólico Fetal/diagnóstico , Testes Neuropsicológicos/normas , Atenção , Criança , Feminino , Transtornos do Espectro Alcoólico Fetal/patologia , Humanos , Masculino
6.
Neurophotonics ; 5(1): 011013, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28983491

RESUMO

OBJECTIVE: although the preponderance of research on functional brain activity investigates mean group differences, mounting evidence suggests that variability in neural activity is beneficial for optimal central nervous system (CNS) function. Independent of mean signal estimates, recent findings have shown that neural variability diminishes with age and is positively associated with cognitive performance, underscoring its adaptive nature. The present investigation sought to employ functional near infrared spectroscopy (fNIRS) to derive two operationalizations of cerebral oxygenation, representing mean and variability [using standard deviation (SD)] in neural activity, and to specifically contrast these mean- and SD-oxyhemoglobin (HbO) estimates as predictors of cognitive function. METHOD: a total of 25 older adults (71 to 81 years of age) completed a test of cognitive interference (Multisource Interference Task) while undergoing fNIRS recording using a multichannel continuous-wave optical imaging system (TechEn CW6) over bilateral prefrontal cortex (PFC). Time-varying covariation models were employed to simultaneously estimate the within- and between-person effects of cerebral oxygenation on behavioral performance fluctuations. RESULTS: mean effects were predominantly observed at the between-person level and suggest that greater concentrations of HbO are associated with slower and less accurate performance. Greater HbO variability at the between-person level was associated with slower performance, but was associated with faster performance at the within-person level. CONCLUSIONS: these findings are in keeping with assertions that mean and variability confer complementary (as opposed to redundant) sources of information regarding the effective functioning of a neural system and suggest that fNIRS is a viable methodology for capturing meaningful variance in the hemodynamic response that is characteristic of adaptive CNS function.

7.
J Int Neuropsychol Soc ; 24(1): 57-66, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28720169

RESUMO

OBJECTIVES: We sought to clarify the nature of self-reported cognitive function among healthy older adults by considering the short-term, within-person association (coupling) of subjective cognitive function with objective cognitive performance. We expected this within-person coupling to differ between persons as a function of self-perceived global cognitive decline and depression, anxiety, or neuroticism. METHODS: This was an intensive measurement (short-term longitudinal) study of 29 older adult volunteers between the ages of 65 and 80 years without an existing diagnosis of dementia or mild cognitive impairment. Baseline assessment included neuropsychological testing and self-reported depression, anxiety, and neuroticism, as well as self- and informant-reported cognitive decline (relative to 10 years previously). Intensive within-person measurement occasions included subjective ratings of cognitive function paired with performance on a computerized working memory (n-back) task; each participant attended four or five assessments separated by intervals of at least one day. Statistical analysis was comprised of multilevel linear regression. RESULTS: Comparison of models suggested that both neuroticism and self-rated cognitive decline explained unique variance in the within-person, across-occasion coupling of subjective cognitive function with objective working memory performance. CONCLUSIONS: Self-ratings of cognition may accurately reflect day-to-day variations in objective cognitive performance among older adults, especially for individuals lower in neuroticism and higher in self-reported cognitive decline. Clinicians should consider these individual differences when determining the validity of complaints about perceived cognitive declines in the context of otherwise healthy aging. (JINS, 2018, 24, 57-66).


Assuntos
Envelhecimento/fisiologia , Ansiedade/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Depressão/fisiopatologia , Autoavaliação Diagnóstica , Neuroticismo , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Individualidade , Estudos Longitudinais , Masculino , Autorrelato
8.
J Alzheimers Dis ; 52(2): 757-74, 2016 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-27060951

RESUMO

INTRODUCTION: Subjective cognitive decline (SCD) in older adults is a condition with a complex phenomenology and diverse etiologies including (but not limited to) mood, personality, and health concerns, as well as biomarkers of preclinical Alzheimer's disease such as amyloid-ß deposition and gray matter volume loss. Approximately 60% of affected persons are estimated to decline to Alzheimer's dementia. Regardless of etiology, persons with SCD may be optimal targets for early intervention. OBJECTIVE: To ascertain the feasibility and impact of mindfulness training (MT) as an early intervention in persons with SCD. METHODS: Using a single-blind, randomized controlled trial design, older adults with (n = 14) and without (n = 22) SCD were randomized to either MT or a control condition of psychoeducation (PE) on cognitive aging. EEG/ERP (specifically, the P3 component), structural MRI, and self-report measures of psychological functioning were obtained within 4 weeks prior to and within 2 weeks following intervention. RESULTS: MT resulted in decreased reaction time intra-individual variability for all participants, with a selective increase in the P3 event-related component for those with SCD. Compared with PE, MT also resulted in an increase in percent volume brain change in structural MRI. Finally, all SCD participants reported a decrease in cognitive complaints and increase in memory self-efficacy following intervention. DISCUSSION: Results suggest that MT is a feasible early intervention in persons with SCD. Longer-term follow-up with larger sample sizes will determine whether MT can slow the rate of decline in persons who may be at risk for Alzheimer's dementia.


Assuntos
Disfunção Cognitiva/terapia , Atenção Plena/métodos , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Eletroencefalografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Neuroimagem , Projetos Piloto , Método Simples-Cego , Resultado do Tratamento
9.
Biol Psychol ; 103: 144-51, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25204705

RESUMO

Subjective cognitive decline (SCD) has recently been proposed as the earliest stage of pathologic cognitive decline in older adults. Longitudinal research suggests that many individuals with SCD go on to develop mild cognitive impairment or Alzheimer's disease. However, those with SCD typically appear normal on standardized neuropsychological testing, and as of yet there are no reliable objective measures discriminating those with SCD from healthy peers. Two groups of healthy older adults (ages 65-80), who self-identified as being with (n=17) or without SCD (n=23), completed self-report measures and objective measures of cognition. Groups did not differ on demographic variables, estimated cognitive reserve, or clinical neuropsychological testing. However, self-identifying as having SCD predicted clear differences in the P3 event-related potential in response to an attention control task, over and above any contributions from mood, anxiety, or neuroticism. Results suggest that using direct neural measures of information processing might be useful where standardized clinical tools are insensitive in those with SCD.


Assuntos
Doença de Alzheimer/diagnóstico , Atenção/fisiologia , Encéfalo/fisiopatologia , Cognição/fisiologia , Disfunção Cognitiva/diagnóstico , Potenciais Evocados/fisiologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Progressão da Doença , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Autorrelato
10.
Neurosci Lett ; 523(2): 131-4, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22750152

RESUMO

Weak (1 µT) physiologically patterned magnetic fields produce changes in behavioral, physiological, and cellular activity. In the present experiments 12 temporal samples of the electroencephalographic anomaly and normal activity of a person (SLH) whose proximity reliably affected the brain activity of others were extracted from QEEG data, digitized, and presented as equivalent magnetic field patterns to B16 mouse melanoma cells. Only two of the patterns, both originating from the primary source (right temporal lobe) of the EEG anomaly reduced the cell growth by one-third compared to the other patterns extracted from his QEEG or sham field exposures. In previous experiments these EEG transients were also associated with marked increases in photon emissions from the right side of SLH's head. The results suggest that the intrinsic complexity of electroencephalographic patterns of some people, when amplified appropriately and applied as computer-generated magnetic fields in the three spatial planes, could diminish cancer cell growth.


Assuntos
Campos Magnéticos , Melanoma Experimental/patologia , Animais , Proliferação de Células , Eletroencefalografia , Humanos , Camundongos , Software , Lobo Temporal/fisiologia , Células Tumorais Cultivadas
11.
Neurosci Lett ; 516(1): 54-6, 2012 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-22484013

RESUMO

Previous correlations between geomagnetic activity and quantitative changes in electroencephalographic power revealed particular associations with the right parietal lobe for theta activity and the right frontal region for gamma activity. In the present experiment subjects were exposed to either no field (sham conditions) or to either 20 nT or 70 nT, 7 Hz, amplitude modulated (mHz range) magnetic fields for 30 min. Quantitative electroencephalographic (QEEG) measurements were completed before, during, and after the field exposures. After about 10 min of exposure theta power over the right parietal region was enhanced for the 20 nT exposure but suppressed for the 70 nT exposure relative to sham field exposures. The effect dissipated by the end of the exposure. These results support the contention that magnetic field fluctuations were primarily responsible for the significant geomagnetic-QEEG correlations reported in several studies.


Assuntos
Encéfalo/fisiologia , Encéfalo/efeitos da radiação , Estimulação Elétrica/métodos , Eletroencefalografia/efeitos da radiação , Campos Eletromagnéticos , Adulto , Relação Dose-Resposta à Radiação , Fenômenos Ecológicos e Ambientais , Feminino , Humanos , Masculino , Doses de Radiação , Estatística como Assunto , Adulto Jovem
12.
Neurocase ; 18(6): 527-36, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22229671

RESUMO

People who report objects moving in their presence, unusual sounds, glows around other people, and multiple sensed presences but do not meet the criteria for psychiatric disorders have been shown to exhibit electrical anomalies over the right temporal lobes. This article reports the striking quantitative electroencephalography, sLORETA results, and experimental elicitation of similar subjective experiences in a middle-aged woman who has been distressed by these classic phenomena that began after a head injury. She exhibited a chronic electrical anomaly over the right temporoinsular region. The rotation of a small pinwheel near her while she 'concentrated' upon it was associated with increased coherence between the left and right temporal lobes and concurrent activation of the left prefrontal region. The occurrence of the unusual phenomena and marked 'sadness' was associated with increased geomagnetic activity; she reported a similar mood when these variations were simulated experimentally. Our quantitative measurements suggest people displaying these experiences and possible anomalous energies can be viewed clinically and potentially treated.


Assuntos
Lesões Encefálicas/psicologia , Mapeamento Encefálico , Córtex Cerebral/fisiopatologia , Alucinações/psicologia , Parapsicologia , Lesões Encefálicas/complicações , Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Córtex Cerebral/patologia , Eletroencefalografia , Campos Eletromagnéticos , Feminino , Lateralidade Funcional , Alucinações/etiologia , Alucinações/patologia , Alucinações/fisiopatologia , Humanos , Pessoa de Meia-Idade , Lobo Temporal/fisiopatologia , Tomografia/instrumentação
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