Categoría: Papers con abstracts

El trastorno obsesivo-compulsivo es un trastorno psiquiátrico que en un 87% de los casos se vuelve crónico. Se caracteriza por una serie de síntomas que pueden ser agrupados en obsesiones y compulsiones, que pueden llegar a ser altamente invalidantes y afectar el estilo de vida de quienes lo padecen. Es importante entender los mecanismos neurológicos del trastorno obsesivo-compulsivo para poder abordar de manera más eficaz los tratamientos. Este trabajo plantea al modelo frontoestriado como aquel que provee mayor evidencia y explica de manera más acabada los fenómenos neuropsicológicos del TOC, con las áreas cerebrales que se encuentran implicadas en él córtex cingulado anterior, los ganglios basales, y la corteza órbito-frontal. Luego, se vinculan estos resultados con aquellos hallazgos de estudios de potenciales evocados relacionados a eventos (especialmente ERN, N200 y P300) con el fin de explicar más íntegramente lascaracterísticas del trastorno. Las funciones cognitivas que se pueden vincular con loshallazgos de neuroimágenes y ERPs son relativas al procesamiento de la información,decodificación, planificación, atención voluntaria, control inhibitorio, y funcionesejecutivas en general.

Employment is an indicator of socioeconomic status. Unemployment is a worldwide social challenge, especially in emerging countries, accounting for a proportion of the overall higher mortality rates found in these nations. We assessed the relationship between employment status and in-hospital mortality among acute ischemic stroke patients participating in the Argentinean National Stroke Registry (ReNACer), a prospective, country-wide, hospital-based stroke registry aimed at improving quality of stroke care in Argentina. We compared demographic and socioeconomic characteristics, risk factors, acute treatment, and stroke severity between employed and unemployed patients with acute ischemic stroke participating in ReNACer. We developed a multiple logistic regression model to identify predictors of in-hospital mortality. Among the 726 patients with acute ischemic stroke included in the study, 39.5% were unemployed. In-hospital mortality was higher in the patients who were unemployed at the time of the stroke compared with those who were employed (12.0% vs 5.0%; P = .003). On multivariate analysis, being unemployed (odds ratio [OR], 3.58; 95% confidence interval [CI], 1.36-7.37; P = .005), stroke severity (OR, 3.54; 95% CI 1.11-10.40; P = .018), and infarct size >15 mm (OR, 2.80; 95% CI, 1.18-6.60; P = .019) were associated with in-hospital mortality after adjusting for relevant covariates. Social factors may influence poor outcomes after stroke. In the present study, unemployment was associated with a higher risk of adjusted in-hospital mortality. Strategies targeting individuals at high risk of cardiovascular diseases and poorer outcomes should be implemented to reduce stroke impact.

Human communication in a natural context implies the dynamic coordination of contextual clues, paralinguistic information and literal as well as figurative language use. In the present study we constructed a paradigm with four types of video clips: literal and metaphorical expressions accompanied by congruent and incongruent gesture actions. Participants were instructed to classify the gesture accompanying the expression as congruent or incongruent by pressing two different keys while electrophysiological activity was being recorded. We compared behavioral measures and event related potential (ERP) differences triggered by the gesture stroke onset. Accuracy data showed that incongruent metaphorical expressions were more difficult to classify. Reaction times were modulated by incongruent gestures, by metaphorical expressions and by a gesture-expression interaction. No behavioral differences were found between the literal and metaphorical expressions when the gesture was congruent. N400-like and LPC-like (late positive complex) components from metaphorical expressions produced greater negativity. The N400-like modulation of metaphorical expressions showed a greater difference between congruent and incongruent categories over the left anterior region, compared with the literal expressions. More importantly, the literal congruent as well as the metaphorical congruent categories did not show any difference. Accuracy, reaction times and ERPs provide convergent support for a greater contextual sensitivity of the metaphorical expressions.

Increase in use of atypical antipsychotics has been paralleled by an increase in the incidence of intentional and nonintentional overdose. Pediatric cases are uncommon, but may be severe. We describe a case of a child presenting with severe extrapiramidal symptoms, initially interpreted as seizures, caused by a nonintentional intoxication with risperidone, and review management options and the literature.

Neuroleptics having dopamine receptor-blocking properties are frequently responsible for the development of movement disorders. This has been known for many years as these adverse events were identified soon after the introduction of these drugs for the treatment of psychiatric disorders. Parkinsonism, acute dystonic reactions, akathisia, and tardive dyskinesias are the different clinical presentations of these disorders. Tardive dyskinesia is the most problematic among them as it may persist even after discontinuation of the offending drug, and become an irreversible phenomenon. The term «tardive dyskinesia » encompasses a variety of clinical phenomena including stereotypic behaviors, dystonia, myoclonus, and tics. Stereotypies and orobuccolingual dyskinesias are the most frequently observed tardive disorders, particularly in the elderly population exposed to neuroleptics, while dystonic phenomena are more prevalent in younger individuals. The development of these disorders is dependent on the potency of the drug, duration of exposure, and a number of predisposing factors, including age, gender, and presence of organic brain disease. The pathophysiology is rather complex and involves changes in the dopamine synapse both at the pre- and postsynaptic level, as well as plastic changes involving transcription factors and activation of different molecular cascades downstream of the dopamine receptor. The introduction of more novel pharmacological agents, like the so-called atypical neuroleptics, has significantly reduced the incidence of these disorders; however, the prescribing physician has to be aware that a lower risk is not synonymous with absence of risk.

Patients with behavioral variant frontotemporal dementia (bvFTD) exhibit a set of behavioral disturbances that have been strongly associated with involvement of the prefrontal cortex (PFC). Many such disturbances have been linked to impaired moral behavior, especially in regard to «personal » or «emotionally driven » moral dilemmatic judgment, which has been demonstrated to also depend on the integrity of the PFC. In this study, we administered a personal moral dilemma (the footbridge dilemma) and social cognition measures to patients with early bvFTD, who were also assessed with an extensive neuropsychological battery, including moral knowledge, cognitive and emotional empathy, and affective decision-making. BvFTD patients who would push a man off a footbridge (knowing this would kill him) to save the life of five workers who would have been otherwise killed by the train showed significantly lower scores on affective Theory of Mind (ToM) relative to those bvFTD patients who responded negatively. No significant differences were found on other sociodemographic, neuropsychological or social cognition variables. This study reveals that altered dilemmatic judgment may be related to impaired affective ToM, which has important clinical and theoretical implications.

Background. A «dysexecutive » group of patients with Alzheimer disease (AD) has been previously identified, and these patients have been found to present higher frequency of psychiatric symptoms and more pronounced functional impact. This study aimed at evaluating the frequency of neuropsychiatric symptoms in patients with early AD who present with impaired executive functioning. Methods. Thirty patients with early AD diagnosis were divided into a spared (SEF) and an impaired (IEF) executive functioning group according to their performance scores on neuropsychological tests. Their closest relatives or caregivers completed the Cambridge behavioral inventory (CBI), which assesses behavioral symptoms grouped into 13 categories. Results. A significant difference was exclusively found between SEF and IEF in terms of the frequency of stereotypies and repetitive motor behavior (U = 60.5, P = .024). Conclusions. The presence of stereotypies could be associated with a dysexecutive profile in AD patients. These results shed light on the role of frontal circuitry in the expression of motor symptoms in AD and prompt for further research that will contribute to the differential diagnosis both of different subtypes of AD and other types of dementia.

Posterior cortical atrophy (PCA) is a rare early-onset dementing syndrome presenting with visuo-perceptual deficits. Clinicopathologically, it is most commonly considered a form of Alzheimer’s disease. We present the case of a 64-year-old male patient with posterior cortical atrophy who took part in a cognitive rehabilitation programme that included psychoeducation, compensatory strategies, and cognitive exercises. After the cognitive rehabilitation programme, subtle differences were found in visuoperceptual tasks and in the patient’s subjective perception of difficulties. Cognitive rehabilitation may temporarily improve functioning in patients with posterior cortical atrophy.

Background. A «dysexecutive » group of patients with Alzheimer disease (AD) has been previously identified, and these patients have been found to present higher frequency of psychiatric symptoms and more pronounced functional impact. This study aimed at evaluating the frequency of neuropsychiatric symptoms in patients with early AD who present with impaired executive functioning. Methods. Thirty patients with early AD diagnosis were divided into a spared (SEF) and an impaired (IEF) executive functioning group according to their performance scores on neuropsychological tests. Their closest relatives or caregivers completed the Cambridge behavioral inventory (CBI), which assesses behavioral symptoms grouped into 13 categories. Results. A significant difference was exclusively found between SEF and IEF in terms of the frequency of stereotypies and repetitive motor behavior (U = 60.5, P = .024). Conclusions. The presence of stereotypies could be associated with a dysexecutive profile in AD patients. These results shed light on the role of frontal circuitry in the expression of motor symptoms in AD and prompt for further research that will contribute to the differential diagnosis both of different subtypes of AD and other types of dementia.

Se denomina «Deterioro Cognitivo Leve” a un estado transicional entre los cambios cognitivos del envejecimiento normal y un estadio temprano de la demencia. En la actualidad, el constructo deterioro cognitivo leve (DCL) se reconoce como una condición patológica, no como un proceso normal asociado a la edad, y se utiliza específicamente para referirse a un grupo de individuos que presentan cierto grado de déficit cognitivo cuya severidad resulta insuficiente para cumplir criterios de demencia ya que no presentan un compromiso esencial en las actividades de la vida diaria (1). Originalmente el MCI refería a un déficit de memoria en el contexto de funciones no-amnésicas preservadas (DCL amnésico) pero actualmente el término incluye déficits en otras funciones cognitivas más allá de la memoria. El DCL amnésico es posiblemente un estado precursor de la enfermedad de Alzheimer. Los datos neuropatológicos confirman esta transición del DCL amnésico a enfermedad de Alzheimer.