RESUMEN
The orbitofrontal cortex (OFC) plays a crucial role in behavior and is a common site for damage due to different types of injuries, e.g., closed head injuries, cerebrovascular accidents, tumors, neurosurgical interventions. Despite the (severe) behavioral changes following OFC lesions, persons with damage to the OFC appear to be cognitively intact, i.e., at least when assessed by means of standard neuropsychological tests. Meanwhile, neuropsychological tests addressing reversal learning, gambling, and social cognition show a decline in these patients. The goal of the present review is to link the performance of these latter neuropsychological tests to behavior. The results suggest that in patients with orbitofrontal lesions, reversal learning is more associated with behavioral disinhibition and that impairment in recognition of expressed emotion is more associated with social inappropriate behavior. The faux pas test (theory of mind) appears not to be sensitive to orbitofrontal lesions. Future studies should involve a larger numbers of patients with well-defined locations in the OFC and should integrate specific neuropsychological tests and quantitative behavioral measures to better understand the contribution of the OFC to cognition and behavior.
Asunto(s)
Conducta/fisiología , Cognición/fisiología , Corteza Prefrontal/fisiología , Humanos , Teoría de la MenteRESUMEN
OBJECTIVES: Investigating whether cognitive functioning is associated with the perception of one's sexuality in old age. DESIGN: Cross-sectional analysis, using observation cycle 2005/2006 of the population-based prospective cohort of the Longitudinal Aging Study Amsterdam. SETTING: Municipal registries in three Dutch regions. PARTICIPANTS: 1,908 older adults (mean [standard deviation] age: 71 [8.87] years; 54% women). MEASUREMENTS: Sexuality and intimacy were assessed using four questions. Four cognitive domains were assessed: general cognitive functioning (Mini-Mental State Examination), memory performance (Auditory Verbal Learning Test), processing speed (Coding Task), and fluid intelligence (Raven's Coloured Progressive Matrices). Multinomial regression analysis was used, with sexuality as outcome. The interaction effect between gender and sexuality was also tested. RESULTS: Lower fluid intelligence was associated with perceiving sexuality as unimportant; lower general cognitive functioning was associated with perceiving sexuality as unimportant; and lower immediate memory recall was associated with evaluating sexual life as unpleasant. Associations were also found between lower fluid intelligence, processing speed, and general cognitive functioning, and agreeing with sexuality no longer being important. Lower processing speed, general cognitive functioning, and delayed memory recall were associated with disagreeing with a remaining need for intimacy when getting older. Finally, the association between fluid intelligence and perceiving sexuality as important, and the association between immediate memory recall score and evaluating sexual life as pleasant, was only significant in women. The association between lower general cognitive functioning and perceiving sexuality as unimportant seemed stronger in women compared with men. CONCLUSIONS: Higher cognitive functioning was associated with the way in which older people perceive their current sexuality.
Asunto(s)
Envejecimiento/psicología , Cognición/fisiología , Conocimientos, Actitudes y Práctica en Salud , Sexualidad/psicología , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Países Bajos/epidemiología , Pruebas Neuropsicológicas , Estudios Prospectivos , Sistema de RegistrosRESUMEN
BACKGROUND: Known risk factors for Alzheimer's disease and other dementias include medical conditions, genetic vulnerability, depression, demographic factors and mild cognitive impairment. The role of feelings of loneliness and social isolation in dementia is less well understood, and prospective studies including these risk factors are scarce. METHODS: We tested the association between social isolation (living alone, unmarried, without social support), feelings of loneliness and incident dementia in a cohort study among 2173 non-demented community-living older persons. Participants were followed for 3 years when a diagnosis of dementia was assessed (Geriatric Mental State (GMS) Automated Geriatric Examination for Computer Assisted Taxonomy (AGECAT)). Logistic regression analysis was used to examine the association between social isolation and feelings of loneliness and the risk of dementia, controlling for sociodemographic factors, medical conditions, depression, cognitive functioning and functional status. RESULTS: After adjustment for other risk factors, older persons with feelings of loneliness were more likely to develop dementia (OR 1.64, 95% CI 1.05 to 2.56) than people without such feelings. Social isolation was not associated with a higher dementia risk in multivariate analysis. CONCLUSIONS: Feeling lonely rather than being alone is associated with an increased risk of clinical dementia in later life and can be considered a major risk factor that, independently of vascular disease, depression and other confounding factors, deserves clinical attention. Feelings of loneliness may signal a prodromal stage of dementia. A better understanding of the background of feeling lonely may help us to identify vulnerable persons and develop interventions to improve outcome in older persons at risk of dementia.
Asunto(s)
Demencia/epidemiología , Demencia/psicología , Soledad/psicología , Aislamiento Social/psicología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Países Bajos/epidemiología , Prevalencia , Factores de RiesgoRESUMEN
OBJECTIVE: Motivational aspects, emotional factors, and cognition, all of which require intact cognitive functioning may be essential in sexual functioning. However, little is known about the association between cognitive functioning and sexual behavior. The aim of this article is to review the current evidence for the influence of cognitive functioning on sexual behavior in normal aging and dementia. METHODS: A systematic literature search was conducted in PubMed, Ovid, Cochrane, and PsycINFO databases. The databases were searched for English language papers focusing on human studies published relating cognitive functioning to sexual behavior in the aging population. Keywords included sexual behavior, sexuality, cognitive functioning, healthy elderly, elderly, aging and dementia. RESULTS: Eight studies fulfilled our inclusion criteria. Of these studies, five included dementia patients and/or their partners, whereas only three studies included healthy older persons. Although not consistently, results indicated a trend that older people who are not demented and continue to engage in sexual activity have better overall cognitive functioning. Cognitive decline and dementia seem to be associated with diminished sexual behavior in older persons. CONCLUSIONS: The association between cognitive functioning and sexual behavior in the aging population is understudied. The results found are inconclusive.
Asunto(s)
Envejecimiento/psicología , Trastornos del Conocimiento/psicología , Cognición/fisiología , Demencia/psicología , Conducta Sexual/psicología , HumanosRESUMEN
Behavioral changes are commonly observed in patients with dementia and can lead to criminal offenses, even without a history of criminal or antisocial behavior. Due to the growth of the aging population, this poses a rising problem to deal with for the criminal justice system and in general for society. Criminal behavior may include minor crimes such as theft or traffic violations, but also serious crimes such as physical abuse, sexual offense, or murder. In the assessment of criminal behavior among elderly (first-time) offenders, it is important to be aware of possible neurodegenerative diseases at the time of the crime. This book chapter provides an overview on criminal behavior in the elderly and specifically discusses existing literature on patients suffering from a neurodegenerative disease, including Alzheimer disease, vascular dementia, frontotemporal dementia, Parkinson disease, and Huntington disease. Each section is introduced by a true case to illustrate how the presence of a neurodegenerative disease may affect the criminal judgment. The chapter ends with a summary, multifactorial model of crime risk, future perspectives, and concluding remarks.
Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Huntington , Enfermedades Neurodegenerativas , Enfermedad de Parkinson , Anciano , Humanos , Conducta CriminalRESUMEN
BACKGROUND: Although advance directives may seem useful instruments in decision-making regarding incompetent patients, their validity in cases of dementia has been a much debated subject and little is known about their effectiveness in practice. This paper assesses the contribution of advance directives to decision-making in the care of people with dementia, with a special focus on non-treatment directives and directives for euthanasia. METHODS: The relevant problems from the ethical debate on advance directives in cases of dementia are summarized and we discuss how these relate to what is known from empirical research on the validity and effectiveness of advance directives in the clinical practice of dementia care. RESULTS: The ethical debate focuses essentially on how to respond to the current wishes of a patient with dementia if these contradict the patient's wishes contained in an advance directive. The (very limited) empirical data show that the main factors in medical decision-making in such cases is not the patient's perspective but the medical judgment of the physician and the influence of relatives. Insight into the experiences and wishes of people with dementia regarding advance directives is totally lacking in empirical research. CONCLUSIONS: Ethics and actual practice are two "different worlds" when it comes to approaching advance directives in cases of dementia. It is clear, however, that the use of advance directives in practice remains problematic, above all in cases of advance euthanasia directives, but to a lesser extent also when non-treatment directives are involved. Although generally considered valid, their effectiveness seems marginal. Further empirical research into the (potential) value of advance directives in dementia care is recommended.
Asunto(s)
Directivas Anticipadas , Demencia/terapia , Adhesión a las Directivas Anticipadas/ética , Adhesión a las Directivas Anticipadas/psicología , Directivas Anticipadas/ética , Directivas Anticipadas/legislación & jurisprudencia , Directivas Anticipadas/psicología , Anciano , Toma de Decisiones , Demencia/psicología , Eutanasia Pasiva/psicología , Humanos , Competencia Mental/psicologíaRESUMEN
OBJECTIVE: The need for information about the disease and coping with the consequences, as well as on available care and welfare services, is frequently unmet in people with dementia and their carers. To provide carers of community-dwelling people with dementia with tailored information, the DEMentia-specific dynamic interactive social chart (DEM-DISC) was developed. The impact on the daily life of people with dementia and their carers, the user friendliness and usefulness of a first prototype of DEM-DISC was evaluated. METHOD: DEM-DISC was tested among informal carers in a pretest-posttest control group design. Fourteen informal carers could access DEM-DISC at home during a two month period. Fourteen controls did not have access to DEM-DISC. Data were collected by separate interviews with people with dementia and carers at pretest and posttest, by means of digital logging, short telephone interviews, and a bottleneck checklist during the intervention period. RESULTS: People with dementia and informal carers reported more met and less unmet needs after DEM-DISC use and carers in the experimental group reported higher levels of competence than controls. Although they were not explicitly satisfied with this first prototype of DEM-DISC, carers found DEM-DISC easy to learn and relatively user friendly. Carers acknowledged the system's benefits. CONCLUSION: The positive effects might be caused by the systematic and tailored individual way of information provisioning by DEM-DISC. It would be worthwhile to continue to develop DEM-DISC and to conduct randomized trials on the impact on patients and carers as well as the impact on nursing home admission and healthcare expenditure.
Asunto(s)
Demencia/enfermería , Internet , Evaluación de Necesidades , Relaciones Profesional-Paciente , Adaptación Psicológica , Anciano , Comportamiento del Consumidor , Femenino , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Proyectos Piloto , Instituciones Residenciales , Encuestas y Cuestionarios , Interfaz Usuario-ComputadorRESUMEN
AIM: To evaluate previously developed classification models to make implementation in primary care possible and aid early identification of persons at risk for dementia. METHODS: Data were drawn from the OCTO-Twin study. At baseline, 521 persons >or= 80 years of age were nondemented, and for 387 a blood sample was available. Predictors of dementia were collected and analyzed in initially nondemented persons using generalized estimating equations and Cox survival analyses. RESULTS: In the basic model using predictors already known or easily obtained (basic set), the mean 2-year predictive value increased from 6.9 to 28.8% in persons with memory complaints and an MMSE score Asunto(s)
Anciano de 80 o más Años/psicología
, Demencia/clasificación
, Demencia/diagnóstico
, Atención Primaria de Salud
, Medición de Riesgo/clasificación
, Consumo de Bebidas Alcohólicas/epidemiología
, Biomarcadores
, Análisis Costo-Beneficio
, Interpretación Estadística de Datos
, Demencia/economía
, Depresión/psicología
, Diabetes Mellitus/psicología
, Femenino
, Humanos
, Estudios Longitudinales
, Masculino
, Trastornos de la Memoria/diagnóstico
, Trastornos de la Memoria/psicología
, Modelos Estadísticos
, Pruebas Neuropsicológicas
, Pronóstico
, Escalas de Valoración Psiquiátrica
, Medición de Riesgo/métodos
, Medición de Riesgo/estadística & datos numéricos
, Fumar/psicología
, Suecia/epidemiología
, Estudios en Gemelos como Asunto
RESUMEN
BACKGROUND/AIMS: The goal of the present study was to evaluate the diagnostic accuracy of the core diagnostic criteria for frontotemporal dementia (FTD) [Neary D, et al: Neurology 1998;51:1546-1554] within a memory clinic population. METHODS: The 5 core diagnostic criteria for FTD were operationalised in an informant-based written questionnaire. For a diagnosis of FTD the total clinical picture was weighted with findings on additional investigations and possible exclusion criteria, with follow-up of at least 1 year. RESULTS: The operationalised core criteria for FTD had a sensitivity of 79% (95% CI = 57-92) and a specificity of 90% (95% CI = 85-94). CONCLUSION: The core diagnostic criteria for FTD applied in a caregiver questionnaire have good diagnostic accuracy among subjects without advanced dementia attending a memory clinic. This stresses the importance of the informant-based history in the differential diagnosis of dementia.
Asunto(s)
Demencia/diagnóstico , Demencia/epidemiología , Trastornos de la Memoria/epidemiología , Trastornos de la Memoria/terapia , Anciano , Anciano de 80 o más Años , Instituciones de Atención Ambulatoria , Encéfalo/diagnóstico por imagen , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/epidemiología , Consenso , Diagnóstico Diferencial , Femenino , Fluorodesoxiglucosa F18 , Humanos , Incidencia , Masculino , Trastornos de la Memoria/diagnóstico , Persona de Mediana Edad , Pruebas Neuropsicológicas , Grupo de Atención al Paciente , Tomografía de Emisión de Positrones , Radiofármacos , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios , Tomografía Computarizada de Emisión de Fotón ÚnicoRESUMEN
OBJECTIVES: This study investigates whether, and if so how, anxiety symptoms are related to cognitive decline in elderly persons and whether anxiety symptoms precede cognitive decline. METHOD: Data were obtained from the Longitudinal Aging Study Amsterdam. Anxiety symptoms were measured with the Hospital Anxiety and Depression Scale. General cognitive functioning was measured with the Mini-Mental State Examination, episodic memory with the Auditory Verbal Learning Test, fluid intelligence with the Raven's Coloured Progressive Matrices and information processing speed with the coding task. Multilevel analyses were performed to investigate the relationship between anxiety symptoms and cognitive decline over 9 years, taking into account confounding variables. RESULTS: Although not consistent across all dimensions of cognitive functioning, a curvilinear effect of anxiety on cognitive performance was found. Furthermore, we found that previous measurement of anxiety symptoms were not predictive of cognitive decline at a later time-point. CONCLUSION: This study suggests that the effect of anxiety on cognition depends on the severity of the present anxiety symptoms with mild anxiety associated with better cognition, whereas more severe anxiety is associated with worse cognition. The effect of anxiety symptoms on cognitive functioning seems to be a temporary effect, anxiety is not predictive of cognitive decline.
Asunto(s)
Envejecimiento/psicología , Ansiedad/fisiopatología , Cognición , Anciano , Anciano de 80 o más Años , Ansiedad/etiología , Femenino , Humanos , Entrevistas como Asunto , Estudios Longitudinales , Masculino , Países BajosRESUMEN
OBJECTIVE: Amygdalohippocampectomy (AHE) is the resective surgery for medically intractable mesial temporal lobe epilepsy. To date no study has investigated a wide range of neuropsychiatric symptoms in right AHE outpatients. PATIENTS AND METHODS: Three patients with right AHE participated in this study. The control group are patients with cognitive complaints with no history of epilepsy or neurological impairment and no structural abnormalities on the MRI/CT. We expected no difference in verbal memory compared to the controls. Concerning affective Theory of Mind (ToM) we expect a difference between controls and AHE patients. In terms of behavior it is expected that coping and behavioral questionnaires do not significantly differ between AHE and controls, but that proxies of AHE patients do report more behavioral/psychiatric symptoms. RESULTS: No significant difference was found between groups concerning the cognitive functions. For affective ToM we did find a significant difference (p=0.044). A significant difference for the use of more reassuring thoughts (p=0.006) and a trend for less passive reactions on the coping questionnaire, suggesting an 'active coping style'. Overall, AHE patients report fewer problems the self- reported questionnaires. Proxies of the AHE patients reported a trend for more behavioral disinhibition compared to proxy ratings of the control group. CONCLUSION: Right AHE patients underestimate their behavioral and emotional changes due to self-awareness deficits. Ratings of significant others are of immense importance for the detection of psychiatric and behavioral problems. Lesions in the amygdala- orbitofrontal cortex connection disrupt the emotional network, which might explain our results.
Asunto(s)
Amígdala del Cerebelo/diagnóstico por imagen , Amígdala del Cerebelo/cirugía , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/cirugía , Hipocampo/diagnóstico por imagen , Hipocampo/cirugía , Adulto , Estudios Transversales , Epilepsia del Lóbulo Temporal/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas NeuropsicológicasRESUMEN
Inflammation in Alzheimer's disease (AD) may be assessed using (R)-[(11)C]PK11195 and positron emission tomography. Data can be analyzed using the simplified reference tissue model, provided a suitable reference region is available. This study evaluates various reference regions for analyzing (R)-[(11)C]PK11195 scans in patients with mild cognitive impairment (MCI) and probable AD. Healthy subjects (n=10, 30+/-10 years and n=10, 70+/-6 years) and patients with MCI (n=10, 74+/-6 years) and probable AD (n=9, 71+/-6 years) were included. Subjects underwent a dynamic three-dimensional (R)-[(11)C]PK11195 scan including arterial sampling. Gray matter, white matter, total cerebellum and cerebrum, and cluster analysis were evaluated as reference regions. Both plasma input binding potentials of these reference regions (BP(PLASMA)) and corresponding reference region input binding potentials of a target region (BP(SRTM)) were evaluated. Simulations were performed to assess cluster analysis performance at 5% to 15% coefficient of variation noise levels. Reasonable correlations for BP(PLASMA) (R(2)=0.52 to 0.94) and BP(SRTM) (R(2)=0.59 to 0.76) were observed between results using anatomic regions and cluster analysis. For cerebellum white matter, cerebrum white matter, and total cerebrum a considerable number of unrealistic BP(SRTM) values were observed. Cluster analysis did not extract a valid reference region in 10% of the scans. Simulations showed that potentially cluster analysis suffers from negative bias in BP(PLASMA). Most anatomic regions outperformed cluster analysis in terms of absence of both scan rejection and bias. Total cerebellum is the optimal reference region in this patient category.
Asunto(s)
Enfermedad de Alzheimer/diagnóstico por imagen , Antineoplásicos , Trastornos del Conocimiento/diagnóstico por imagen , Isoquinolinas , Adulto , Anciano , Algoritmos , Antineoplásicos/farmacocinética , Volumen Sanguíneo/fisiología , Análisis por Conglomerados , Simulación por Computador , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Isoquinolinas/farmacocinética , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Modelos Neurológicos , Tomografía de Emisión de PositronesRESUMEN
Activated microglia can be visualised using (R)-[(11)C]PK11195 (1-[2-chlorophenyl]-N-methyl-N-[1-methyl-propyl]-3-isoquinoline carboxamide) and positron emission tomography (PET). In previous studies, various methods have been used to quantify (R)-[(11)C]PK11195 binding. The purpose of this study was to determine which parametric method would be best suited for quantifying (R)-[(11)C]PK11195 binding at the voxel level. Dynamic (R)-[(11)C]PK11195 scans with arterial blood sampling were performed in 20 healthy and 9 Alzheimer's disease subjects. Parametric images of both volume of distribution (V(d)) and binding potential (BP) were obtained using Logan graphical analysis with plasma input. In addition, BP images were generated using two versions of the basis function implementation of the simplified reference tissue model, two versions of Ichise linearisations, and Logan graphical analysis with reference tissue input. Results of the parametric methods were compared with results of full compartmental analysis using nonlinear regression. Simulations were performed to assess accuracy and precision of each method. It was concluded that Logan graphical analysis with arterial input function is an accurate method for generating parametric images of V(d). Basis function methods, one of the Ichise linearisations and Logan graphical analysis with reference tissue input provided reasonably accurate and precise estimates of BP. In pathological conditions with reduced flow rates or large variations in blood volume, the basis function method is preferred because it produces less bias and is more precise.
Asunto(s)
Encéfalo/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Isoquinolinas/farmacocinética , Microglía/diagnóstico por imagen , Radiofármacos/farmacocinética , Adulto , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Encéfalo/irrigación sanguínea , Radioisótopos de Carbono/farmacocinética , Estudios de Evaluación como Asunto , Humanos , Tomografía de Emisión de Positrones , Sensibilidad y Especificidad , Distribución TisularRESUMEN
BACKGROUND: The apolipoprotein E (ApoE) e4 polymorphism is linked to increased mortality rates, Alzheimer's disease, and cardiovascular disease in older people, but previous studies have largely failed to detect an effect on self-reported mobility disability. We hypothesized that poor performance on mobility-related tests may provide a better measure of effects, and we aimed to estimate the extent to which the ApoE e4 allele increases risks of poor performance on measured mobility and self-reported mobility disability compared to e3/3, in a medium-sized population cohort. METHODS: Data were from 1262 people at baseline older than 65 years from the Longitudinal Aging Study Amsterdam (LASA), followed up for 6 years. Age- and sex-adjusted logistic regression models were used to explore associations. RESULTS: At baseline, those individuals with an e4 allele had an odds ratio of 2.26 (95% confidence interval, 1.31-3.90) for poor performance on gait speed testing (<0.4 m/s) and 1.94 (95% confidence interval, 1.19-3.16) for five chair stands (> or =20 s), compared to those with e3/3 status. At follow-up, associations between e4 status and incident poor performance on the chair stand test was significant. Associations with self-reported inability or need for help walking for 5 minutes or for climbing 15 steps were nonsignificant throughout. CONCLUSIONS: The ApoE e4 polymorphism is associated with a substantial excess of mobility limitation. The impact is detectable by performance testing, but not by self-reports. Poor results on mobility performance tests may provide a phenotype of ageing.
Asunto(s)
Apolipoproteínas E/genética , Movimiento/fisiología , Anciano , Anciano de 80 o más Años , Alelos , Apolipoproteína E4 , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Análisis de Regresión , AutorrevelaciónRESUMEN
A broad memory test battery (reflecting explicit and implicit memory functioning) was administered to a heterogeneous sample of initially nondemented, community-dwelling elderly subjects. To examine the profile of preclinical dementia, subjects were tested twice: At baseline, all subjects were nondemented according to Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994) criteria; 2 years later, a subgroup had developed dementia. Performance of the preclinically demented subjects was best characterized, relative to that of cognitively impaired subjects who did not develop dementia 2 years later, by an inability to benefit at recall from semantic relations and by absent repetition priming effects. The authors conclude that in addition to testing episodic memory functioning, it is important to be aware of semantic and implicit memory deficits in the early assessment of dementia.
Asunto(s)
Trastornos del Conocimiento/diagnóstico , Demencia/diagnóstico , Memoria/clasificación , Memoria/fisiología , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Trastornos del Conocimiento/complicaciones , Demencia/complicaciones , Demografía , Análisis Discriminante , Femenino , Humanos , Estudios Longitudinales , Masculino , Escala del Estado Mental/estadística & datos numéricos , Pruebas Neuropsicológicas/estadística & datos numéricos , Valor Predictivo de las PruebasRESUMEN
BACKGROUND: If specific symptom profiles of depressive disorders in the elderly are related to a specific etiology, this could have implications for everyday clinical practice. We hypothesized that a "motivational" profile, with symptoms such as psychomotor change, loss of interest and loss of energy, could clinically separate patients with predominantly vascular or degenerative risk indicators from patients with inflammatory risk indicators. METHODS: A total of 4051 subjects participated in a study on mental health problems in community-dwelling elderly. Information on psychiatric symptoms, demographic and medical status, previous history and family history was obtained. We distinguished three subgroups according to predominant somatic risk-indicators; vascular, degenerative and inflammatory groups. RESULTS: Motivational symptoms were associated with vascular or degenerative risk-indicators for depression; psychomotor change with both indicators; loss of energy with vascular, though also with the inflammatory indicator, and thinking/concentration disturbance with the degenerative indicator. The so-called mood symptoms of depression, especially thoughts of death, were more strongly related with the inflammatory risk-indicator. Melancholic symptoms like appetite and sleep disturbances were more strongly associated with the inflammatory risk-indicator. LIMITATIONS: Etiological classification was not confirmed by additional investigations such as laboratory findings or MRI brain scans. CONCLUSION: This study showed that in patients with a late-life depression specific symptoms of the depressive disorder may reflect the predominant underlying pathogenic mechanism.
Asunto(s)
Encéfalo/irrigación sanguínea , Encéfalo/patología , Trastornos Cerebrovasculares/epidemiología , Trastorno Depresivo Mayor/epidemiología , Estado de Salud , Inflamación/epidemiología , Edad de Inicio , Anciano , Anciano de 80 o más Años , Circulación Cerebrovascular/fisiología , Trastornos Cerebrovasculares/fisiopatología , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/epidemiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Motivación , Pruebas Neuropsicológicas , Estudios Prospectivos , Trastornos Psicomotores/epidemiología , Trastornos Psicomotores/fisiopatología , Factores de RiesgoRESUMEN
In this functional MRI (fMRI) study, we investigated ageing effects on motor skill learning. We applied an adapted version of the serial reaction time (SRT) task to extensive groups of young (N=26) and elderly (N=40) subjects. Since indications have been provided for age-related shrinkage of brain regions assumed to be critical to motor skill learning, we tested the hypothesis that age effects on implicit sequence learning are larger on a neurofunctional level than on a behavioural level. The SRT task consisted of two identical scan sessions, in which subjects had to manually trail an asterisk appearing serially in one of four spatial positions by means of button-pressing. Reliable response time reductions were already found in the first session for both the young and the elderly groups, when comparing a fixed sequence condition to a random sequence, but the learning effect was greater for the young subjects. In the second session, though, both groups showed a similar degree of learning. This indicates that implicit sequence learning is still intact in elderly adults, but that the rate of learning is somewhat slower. Reliable learning-related changes in brain activity were also observed. A similar network of brain regions was recruited by both groups during the fixed compared to the random sequence, involving several regions that have been previously associated with implicit sequence learning, including bilateral parietal, and frontal regions, the supplementary motor area (SMA), cerebellum and the basal ganglia. The direct group comparison did not reveal any differences in brain activity. In addition, we did not observe any significant differences in activity when comparing the different sessions either, neither for the young nor for the elderly subjects. Hence, we did not find indications for an age-related functional reorganisation of neural networks involved in motor sequence learning. In view of earlier reports of pronounced ageing effects on the performance on declarative memory tasks, our finding of age-related sparing of processes that sustain motor skill learning, provides further support for the proposition of different memory systems relying on different brain substrates.
Asunto(s)
Envejecimiento/fisiología , Mapeo Encefálico , Corteza Cerebral/fisiología , Aprendizaje/fisiología , Destreza Motora/fisiología , Red Nerviosa/fisiología , Adulto , Anciano , Ganglios Basales/fisiología , Potenciales Evocados , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tiempo de Reacción/fisiologíaRESUMEN
Age-related impairments in episodic memory have been related to a deficiency in semantic processing, based on the finding that elderly adults typically benefit less than young adults from deep, semantic as opposed to shallow, nonsemantic processing of study items. In the present study, we tested the hypothesis that elderly adults are not able to perform certain cognitive operations under deep processing conditions. We further hypothesised that this inability does not involve regions commonly associated with lexical/semantic retrieval processes, but rather involves a dysfunction of the medial temporal lobe (MTL) memory system. To this end, we used functional MRI on rather extensive groups of young and elderly adults to compare brain activity patterns obtained during a deep (living/nonliving) and a shallow (uppercase/lowercase) classification task. Common activity in relation to semantic classification was observed in regions that have been previously related to semantic retrieval, including mainly left-lateralised activity in the inferior prefrontal, middle temporal, and middle frontal/anterior cingulate gyrus. Although the young adults showed more activity in some of these areas, the finding of mainly overlapping activation patterns during semantic classification supports the idea that lexical/semantic retrieval processes are still intact in elderly adults. This received further support by the finding that both groups showed similar behavioural performances as well on the deep and shallow classification tasks. Importantly, though, the young revealed significantly more activity than the elderly adults in the left anterior hippocampus during deep relative to shallow classification. This finding is in line with the idea that age-related impairments in episodic encoding are, at least partly, due to an under-recruitment of the medial temporal lobe memory system.
Asunto(s)
Envejecimiento/fisiología , Mapeo Encefálico , Procesos Mentales/fisiología , Reconocimiento de Normas Patrones Automatizadas , Lóbulo Temporal/fisiología , Adulto , Anciano , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Aprendizaje Verbal/fisiologíaRESUMEN
Insulin-like growth factor I (IGF-I) deficiency may be involved in cognitive deficits seen with aging, and in neurodegenerative diseases such as Alzheimer's disease. The objective of this study was to investigate whether IGF-I is associated with cognitive performance and 3-year cognitive decline in 1318 subjects, aged 65-88 years. Cross-sectionally, IGF-I was directly related to information processing speed, memory, fluid intelligence, and Mini-Mental State Examination (MMSE) score, but these associations did not remain significant after adjustment for age and other factors. Analysis in quintiles of IGF-I revealed a threshold effect of low IGF-I on information processing speed, with lower speed in subjects in the lowest quintile of IGF-I (<9.4 nmol/l)(1) versus those in the other four quintiles (fully adjusted B=-0.89; 95% CI, -1.72 to -0.05). This threshold of low IGF-I was also observed for 3-year decline in information processing speed (adjusted RR=1.78; 95% CI, 1.19-2.68). In summary, this study suggests that IGF-I levels below 9.4 nmol/l are negatively associated with both the level and decline of information processing speed.
Asunto(s)
Trastornos del Conocimiento/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Trastornos del Conocimiento/psicología , Intervalos de Confianza , Estudios Transversales , Femenino , Estudios de Seguimiento , Humanos , Factor I del Crecimiento Similar a la Insulina/deficiencia , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
It is not clear which specific cognitive function is strongest related to falls. To investigate this, not only "general cognitive functioning," but also "nonverbal and abstract reasoning," "information processing speed," and "immediate memory" were related to falls. Furthermore, relevant effect modifiers, confounders, and mediators were identified. This study was performed within the Longitudinal Aging Study Amsterdam (LASA), a multidisciplinary, prospective cohort study. In this study (n = 1437), an interaction between "immediate memory" and age was found. In persons aged 75 years and over, "immediate memory," as measured by the 15 Words Test, showed to be an independent risk factor for falls. Part of this relationship was explained by the mediating effects of activity, mobility, and grip strength. The association between the other cognitive functions and falls was only statistically significant in univariate analysis. We conclude that "immediate memory" is an independent risk factor for recurrent falls in persons aged 75 years and older.