The paradox of quetiapine in obsessive-compulsive disorder

Schizophrenia and obsessive-compulsive disorder (OCD) have historical, clinical, and epidemiological links. The clinical use of atypical neuroleptics (ie, dual serotonin-dopamine antagonists) to treat both conditions sheds a new light on them. We report the first two cases of obsessive-compulsive symptoms (OCS) induced by quetiapine in schizophrenia patients. A case of successful augmentation by quetiapine in refractory OCD is also presented. A review of the literature on OCS induced by atypical neuroleptics follows. This paradoxically induced OCD symptomology in schizophrenia patients administered atypical neuroleptics is discussed from new pathophysiological and clinical perspectives. The discussion emphasizes the prognostic implications of OCS in schizophrenia and available therapies for this comorbidity.     

APP23 mice as a model of Alzheimer's disease: an example of a transgenic approach to modeling a CNS disorder

Animal models are considered essential in research ensuing elucidation of human disease processes and subsequently, testing of potential therapeutic strategies. This is especially true for neurodegenerative disorders, in which the first steps in pathogenesis are often not accessible in human patients. Alzheimer's disease is vastly becoming a major medical and socioeconomic problem in our aging society. Valid animal models for this uniquely human condition should exhibit histopathological, biochemical, cognitive, and behavioral alterations observed in Alzheimer's disease patients. Major progress has been made since the understanding of the genetic basis of Alzheimer's disease and the development and improvement of transgenic mouse models. All present Alzheimer's disease models developed are partial but nevertheless essential in further unraveling the nature and spatial and temporal development of the complex molecular pathology underlying this condition. One of the more recent transgenic attempts to model Alzheimer's disease is the APP23 transgenic mouse. This article describes the development and assessment of this human amyloid precursor protein overexpression model. We summarize histopathological and biochemical, cognitive and behavioral observations made in heterozygous APP23 mice, thereby emphasizing the model's contribution to clarification of neurodegenerative disease mechanisms. In addition, the first therapeutic interventions in the APP23 model are included.     

The Role of Temperament in the Etiology of Child Psychopathology

A substantial proportion of children and adolescents come to suffer from psychological disorders. This article focuses on the temperament factors that are involved in the pathogenesis of child psychopathology. It is argued that besides the reactive temperament factor of emotionality/neuroticism, the regulative process of effortful control also plays an important role in the etiology and maintenance of internalizing and externalizing problems in youths. More specifically, vulnerability to child psychopathology is determined by a temperament that is characterized by high levels of emotionality/neuroticism and low levels of effortful control. Models are hypothesized in which reactive and regulative temperament factors either have interactive or additive effects on the development of psychological disorders in children, and conceptualized in terms of a developmental psychopathology perspective. Directions for future research and clinical implications of this temperamental view on psychopathology are discussed.     

Psychosocial adaptation in relatives of critically injured patients admitted to an intensive care unit

The aim of this study is to analyze how the length of time a patient spends in an Intensive Care Unit (ICU) affects close relatives, with regard to specific clinical variables of personality, family relationships and fear of death. The study group consisted of 57 relatives of seriously ill patients admitted to the ICU of "Virgen del Rocío" Rehabilitation and Trauma Hospital (Seville, Spain). The instruments applied were: a psychosocial questionnaire, clinical analysis questionnaire, family environment scale and fear of death scale. The relatives of patients admitted to ICU obtained higher scores in hypochondria, suicidal depression, agitation, anxious depression, guilt-resentment, paranoia, psychasthenia, psychological maladjustment and self-expression, and less in fear of their own death, as when compared to interviews with the same relatives 4 years later. The length of time a patient spent in the ICU influenced relatives in some clinical variables of personality, family relationships and fear of death     

AIDS and social exclusion: personality features or adaptive behaviors?

The purpose of this survey is to detect common personality features in people infected with AIDS who have a case history of drug addiction and who live in a situation of social exclusion. The sample comprised 105 male participants from the Autonomous Community of Andalusia, divided into 4 groups: (a) 30 men with AIDS, having an intravenous drug addiction case history and who live in a condition of social exclusion; (b) 30 men with IVDA case history, also living in a situation of social exclusion; (c) 15 men in a social exclusion condition; and (d) 30 men in a condition of social adaptation. The evaluation instruments were an author-designed semi-structured interview and the Multiaxial Clinical Inventory (MCMI-II; Millon, 1987). Although some differences were found, the results indicate that there is no specific personality profile in the "social exclusion" population. People in a condition of social exclusion (AIDS, drug addicts, and poor people) may obtain similar scores in the variables studied, but there is no clear specific personality profile in the excluded population, although there may be certain situations in which the segregated groups present similar behaviors. Furthermore, these behaviors do not always correspond to personality features but are adaptive responses to a harsh and complex reality.     

Simulation of the filtering role of habituation to stimuli

In the context of a medium-term study designed to integrate the simulation of different types and processes of learning-such as classical, operant, and some cognitive types--one must start with other more elementary ones that are facilitators of the more complex types and processes. Of special interest is habituation, owing to the filtering out of irrelevant stimuli, which means that the simulated agent does not have to respond to them. This paper presents two difference functions constructed to computationally simulate the characteristics that define habituation. The behavior of these functions is described, as are differences arising from stimulus intensity and interstimulus intervals. Results are compared with existing empirical data.     

One-year-olds comprehend the communicative intentions behind gestures in a hiding game

This study explored infants' ability to infer communicative intent as expressed in non-linguistic gestures. Sixty children aged 14, 18 and 24 months participated. In the context of a hiding game, an adult indicated for the child the location of a hidden toy by giving a communicative cue: either pointing or ostensive gazing toward the container containing the toy. To succeed in this task children had to do more than just follow the point or gaze to the target container. They also had to infer that the adult's behaviour was relevant to the situation at hand - she wanted to inform them that the toy was inside the container toward which she gestured. Children at all three ages successfully used both types of cues. We conclude that infants as young as 14 months of age can, in some situations, interpret an adult behaviour as a relevant communicative act done for them.     

Tracking multiple targets with multifocal attention

Attention allows us to monitor objects or regions of visual space and select information from them for report or storage. Classical theories of attention assumed a single focus of selection but many everyday activities, such as video games, navigating busy intersections, or watching over children at a swimming pool, require attention to multiple regions of interest. Laboratory tracking tasks have indeed demonstrated the ability to track four or more targets simultaneously. Although the mechanisms by which attention maintains contact with several targets are not yet established, recent studies have identified several characteristics of the tracking process, including properties defining a 'trackable' target, the maximum number of targets that can be tracked, and the hemifield independence of the tracking process. This research also has implications for computer vision, where there is a growing demand for multiple-object tracking.