47 research outputs found
Rapid Acquisition of the Stimulus Response Relationship using Visual Evoked Potentials
No full textThe flash visual evoked potential (FVEP) is an electrical potential recorded with electroencephalogram (EEG) at the occipital cortex. Current FVEP assessment may be elaborated with the acquisition of stimulus response (SR) relation of the visual system. A drawback of this adjustment is the time required for data acquisition. This study aimed to develop an optimal (rapid) stimulus paradigm for assessing the SR relationship using FVEP.SR relationships were obtained using two different protocols in eight healthy participants; one considered 100 stimuli for 10 different intensity levels (standard technique), the other considered 1000 stimuli of varying intensity levels within a fixed intensity range (novel technique). Hypothetically the novel technique produces a similar SR relationship but requiring reduced number of stimuli. However, the present study did not find a significant intensity dependency on the FVEP. Consequently, no mathematical model for the SR relation was fit to the data, and exploration of the novel technique was excluded. Instead, the present study investigated the minimal number of stimuli required to acquire a representative FVEP component. Secondly, the potential change of FVEP components during the experiment was investigated. This study demonstrates that it is possible to acquire a reliable FVEP component with on average 54 stimuli (gross mean (39) + 1 SD (14)), independent of stimulus intensity. Additionally, this study demonstrated that the FVEP components change significantly (p<0.05) for most stimulus intensities when 1000 or more flashes are used; amplitudes increased with time for low intensity stimulation, while amplitudes reduced with time for high intensity stimulation. Although the present study did not find an intensity dependency of the FVEP component, it demonstrated that stimulation time is an important parameter when acquiring SR relationships using FVEP. The stimulation time certainly influenced the SR relationship calculated in the present study. Further studies can and should reduce the number of stimuli to produce a representative SR relationship using FVEP.Biomedical Engineerin
From disturbing behavior to disorder
Get PDFIn veel Westerse landen is het aantal diagnosen van mentale ziekten van kinderen en jongeren in de afgelopen decennia sterk toegenomen. Een ruimere definitie van ziektecategorieën is een verklaring hiervoor. Dit duidt op een versterkte medicalisering van storend gedrag, wat inhoudt dat steeds meer problemen gelden als ‘ziekte’ die om een medische behandeling vraagt. Vanaf de jaren tachtig zou sprake zijn van een proces van biomedicalisering, waarbij men primair kijkt naar de hersenen (nature) als oorzaak van gedragsproblemen, met medicatie als voorkeursbehandeling. De overtuiging dat problemen worden veroorzaakt door de omgeving (nurture), die ook de oplossing kan bieden, is hierdoor in belang afgenomen. Dit proefschrift schetst de verschuivingen in de ideeën van Nederlandse kinderpsychiaters, kinderpsychologen en orthopedagogen over de aard, oorzaken en beste behandeling van gedragsproblemen van kinderen en jongeren in de periode 1950-1990. De verhouding tussen nature en nurture in hun teksten over de meest besproken problemen staat daarin centraal. Het onderzoek toont dat autisme, druk en ongeconcentreerd gedrag en bedplassen al omstreeks 1950 gemedicaliseerde stoornissen waren. Voor agressie en angst gebeurde dat pas na 1980 met de introductie van labels uit het Amerikaanse Diagnostic and Statistical Manual of Mental Disorders. Deze studie laat voor autisme, bedplassen, agressie en angst een verschuiving zien van nurture naar nature in de ideeën over oorzaken en behandeling. Voor autisme gebeurde dit mede onder invloed van de oudervereniging. De mate en het tempo waarin deze verandering zich voltrok, verschillen per gedragsprobleem. Nature en nurture blijken vaak samen te gaan.In recent decades in the West, the number of diagnoses of mental illness in children and adolescents has increased considerably. A possible explanation is that disease categories have widened, indicating an increasing medicalization of problem behavior, for which a medical solution is required. Since the 1980s, moreover, a process of biomedicalization manifests itself in which the cause of behavioral problems is more often found in the brain (nature) and psychopharmaceuticals are preferred as remedy. At the same time, the idea that problems are caused by the environment (nurture) has lost importance. This PhD focuses on the changes in the expert discourse of Dutch child psychiatrists, child psychologists and special- needs educationalists on the nature, causes and treatment of behavioral problems of children and adolescents from the 1950s up to 1990. Special attention is paid to the balance between nature and nurture in the debate on the most frequently discussed problems.The research shows that autism, hyperactivity and concentration problems and bedwetting were medicalized as early as 1950. With the adoption of the medical classifications of the Diagnostic and Statistical Manual of Mental Disorders in the 1980s, professionals started to also conceive of anxiety and aggression as mental disorders. As regards autism, bedwetting, aggression and anxiety, we see a shift from nurture to nature in the etiology and preferred therapy. The degree to which and the rate at which these changes occurred differs between the problems discussed. Nature and nurture turn out to not mutually exclude each other
From defence mechanism to insufficient bladder control:Dutch experts on enuresis nocturna in an age of developing child sciences (1950-1990)
Get PDFThis article discusses the conceptualisation of enuresis nocturna by Dutch experts between c.1950 and 1990, years in which across the West new child sciences rapidly developed. Today, bedwetting is conceived as a mental illness caused by a mixture of nature- and nurture-bound factors. Have organic and environmental causes always figured as twins, even in the post-war decades of predominant environmentalism in psychological theory and clinical practice? Or is only the more recent biological turn in psychiatry responsible for a revaluation of organicism in expert discourses on the aetiology and treatment of childhood mental illnesses such as enuresis nocturna? Using Ian Hacking’s dynamic nominalism as interpretive framework, the article shows that, in the Dutch case, environmental factors continued to be referred to after the biologising of children’s mental problems, alongside an increasingly important role for brain-related, physiological and genetic causes of enuresis nocturna
Between nature and nurture: The diagnosing and treatment of childhood behavioral problems in a Dutch child-psychiatric clinic (1952-1961)
No full textThe conceptualization of enuresis nocturna in three intellectual spaces, the Netherlands 1950-1990
No full text“An oedipal conflict on an epileptic basis”:the diagnosing and treatment of behavioural problems in a Dutch child psychiatric clinic (1952–1962)
Get PDFThis article discusses the diagnosing and treatment of behavioural problems in a pioneering Dutch child psychiatric clinic in the 1950s. This was headed by Theo Hart de Ruyter, the first Dutch professor of child psychiatry and a psychoanalyst. It is generally assumed that during postwar years child psychiatry was primarily influenced by Freudianism with its focus on a nurture-related aetiology of children’s behavioural problems. This assumption has, however, not been tested for the clinical practice. Did nature-bound explanations – referring to a child’s neurological constitution, hereditary predisposition or brain dysfunction – disappear from the consulting room and was treatment with psychotropic drugs anathema to Freudians, in the way it has been suggested? We compare Hart de Ruyter’s theoretical work with the contemporary expert discourse and with the way he and his team diagnosed and treated children, using clinical records. It turns out that both theory and practice and both aetiology and treatment mixed up nature and nurture. The use of an electro-encephalogram to rule out organic causes and of medication to speed up improvement of a child’s behaviour does, however, not undo the predominant adherence of the clinic’s staff to updated versions of Freudianism. It also demonstrates the semi-improvisational nature of early academic child psychiatry
The conceptualization of enuresis nocturna in three intellectual spaces, the Netherlands 1950-1990
No full textBetween nature and nurture:The diagnosing and treatment of childhood behavioral problems in a Dutch child-psychiatric clinic (1952-1961)
No full textThe conceptualization of enuresis nocturna in three intellectual spaces, the Netherlands 1950-1990
No full text
