Categoría: Papers con abstracts

Object and spatial visual working memory are impaired in schizophrenic patients. It is not clear if the impairments reside in each memory subsystem alone or also in the central executive component that coordinates these processes. In order to elucidate which memory component is impaired, we developed a paradigm with single spatial and object working memory tasks and dual ones with two different delays (5 and 30 s). Fifteen schizophrenic patients and 14 control subjects performed these tests. Schizophrenic patients had a poorer performance compared to normal controls in all tasks and in all time delays. Both schizophrenics and controls performed significantly worse in the object task than in the spatial task. The performance was even worse in the dual task compared to the singles ones in schizophrenic patients but not in controls. These data suggest that visuospatial performance deficits in schizophrenia are due to both visuospatial memory subsystems impairments and central executive ones. The pattern of deficits observed points to a codification or evocation deficit and not to a maintenance one.

OBJECTIVE: To investigate the association between focal stroke lesions of the putamen and either attention-deficit/hyperactivity disorder or traits of the disorder (ADHD/Traits). METHOD: Twenty-five children with focal stroke lesions were studied with standardized psychiatric assessments and anatomic brain magnetic resonance imaging. The pattern of lesion overlap in subjects with ADHD/Traits was determined. RESULTS: Fifteen of 25 subjects had ADHD/Traits. The densest area of overlapping lesions (n = 7) in subjects with ADHD/Traits included the posterior ventral putamen. The median lesion volume was 9.7 cm3, and the distribution was highly skewed. Lesion volume was not associated with ADHD/Traits. Therefore the following analyses focused on the 13 subjects with lesions < 10 cm3: ADHD/Traits were exhibited in 6/7 subjects with putamen lesionsversus 2/6 with no putamen lesions (Fisherexacttestp= .1). Half (4/8) of the subjects with ADHD/Traits had overlapping lesions encompassing the posterior ventral putamen. None of the 5 subjects without ADHD/Traits had lesions in this empirically derived region of interest (Fisher exact test p = .1). CONCLUSIONS: Lesions within the dopamine-rich ventral putamen, which is part of the ventral or limbic striatum, tended to increase the risk of ADHD/Traits. ADHD/Traits may therefore be a disinhibition syndrome associated with dysfunction in this cortical-striato-thalamocortical loop.

OBJECTIVE: Early detection and treatment of Bipolar Disorder (BD) determine a significant relief in the considerable burden this disease implies. In order to adequately plan the strategies to guarantee access to treatment, it is useful to consider data which reflect the everyday vicissitudes the people affected by this pathology have to deal with. People on treatment for BD in centres in Argentina and Chile were surveyed, collecting data on their access to diagnosis and treatment. The centre surveyed in Chile, unlike those in Argentina, operates as a specialized unit. METHODOLOGY: An anonymous assisted survey was carried out; a random sample of people assisted in the participating centres with a diagnosis of BD type I or II, and stabilized for a period no shorter than 12 months, was assessed. RESULTS: 100 people were surveyed in Argentina and 69 in Chile (70% women, age 45.2 +/- 14.7, average schooling 12 years). Seventy one percent began symptoms at adult age (28,43 +/- 13 years), 14% during childhood. Age at first consultation was: 30 +/- 12.5; 85% reported having suffered psychotic symptoms, 46.4% suicide attempts, 71% hospitalisations for BD. Sixty-nine percent reported diagnostic delays longer than a year (median 8 years), 75% reported having received other diagnosis prior to their BD diagnosis (62% unipolar depression, 41% schizophrenia). Forty-one percent reported being unemployed. Delays and diagnostic errors were associated to a significant increase in the functional impact reported. CONCLUSION: Approximately 7 out of 10 people report difficulties in the access to a BD diagnosis. These difficulties magnify the already important impact of the disease.

OBJECTIVES: To determine the rate, types, and correlates of psychiatric disorder (PD) following stroke and orthopedic disorders in children and adolescents. METHOD: Children aged 5 to 19 were assessed. The study used a cross-sectional design that compared 29 stroke subjects with 29 congenital clubfoot or scoliosis subjects. Assessments of psychiatric status; cognitive, adaptive, academic, and family functioning; family psychiatric history; neuroimaging; and neurological status were conducted. The main outcome measure was a current PD not present before the stroke or orthopedic disorder. RESULTS: Poststroke PD occurred significantly more often than postorthopedic diagnosis PD (17/29 [59%] versus 4/29 [14%], p < or =.001). Subjects with ongoing poststroke PD had significantly more impaired intellectual and adaptive functioning, higher intensity family psychiatric history scores, and tended toward higher neurological severity index scores, but they were not different regarding lesion volume or family functioning compared with stroke subjects without PD. Regression analyses showed that neurological severity and family psychiatric history independently contributed significantly to predicting PD. CONCLUSIONS: The data suggest that there are significant biopsychosocial correlates of PD in children with focal neurological lesions. These include a relatively abnormal neurological exam, lower IQ, and increased family psychopathology.

One important challenge in neuropsychiatry is how to diagnose depression in patients with acute brain lesions, since there may be an overlap between symptoms of depression and signs associated with the neurologic disease. The best approach is to assess the presence of depressive symptoms using semi-structured or structured psychiatric interviews such as the Present State Exam, the Structured Clinical Interview for DSM-IV, or the Schedules for Clinical Assessment in Neuropsychiatry. The diagnosis of a depressive syndrome should be made using standardized diagnostic criteria for mood disorders due to neurological disease such as in the DSM-IV or the ICD-10. Depression rating scales, such as the Hamilton Depression Scale and the Center for Epidemiologic Scales for Depression may be used to rate the severity of depression and monitor the progression of antidepressant treatment. Most studies in acute and chronic neurologic disorders demonstrated the specificity of both autonomic and psychological symptoms for the syndrome of depression. The present review article examines important considerations before a diagnosis of depression in neurologic disease, discusses a variety of psychiatric instruments that are used to examine the presence and severity of depression in neurologic disease, examines relevant phenomenological issues, and proposes different diagnostic strategies.

Recent work has suggested an association between the orbitofrontal cortex in humans and practical decision making. The aim of this study was to investigate the profile of cognitive deficits, with particular emphasis on decision-making processes, following damage to different sectors of the human prefrontal cortex. Patients with discrete orbitofrontal (OBF) lesions, dorsolateral (DL) lesions, dorsomedial (DM) lesions and large frontal lesions (Large) were compared with matched controls on three different decision-making tasks: the Iowa Gambling Task and two recently developed tasks that attempt to fractionate some of the cognitive components of the Iowa task. A comprehensive battery including the assessment of recognition memory, working memory, planning ability and attentional set-shifting was also administered. Whilst combined frontal patients were impaired on several of the tasks employed, distinct profiles emerged for each patient group. In contrast to previous data, patients with focal OBF lesions performed at control levels on the three decision-making tasks (and the executive tasks), but showed some evidence of prolonged deliberation. DL patients showed pronounced impairment on working memory, planning, attentional shifting and the Iowa Gambling Task. DM patients were impaired at the Iowa Gambling Task and also at planning. The Large group displayed diffuse impairment, but were the only group to exhibit risky decision making. Methodological differences from previous studies of OBF patient groups are discussed, with particular attention to lesion laterality, lesion size and psychiatric presentation. Ventral and dorsal aspects of prefrontal cortex must interact in the maintenance of rational and ‘non-risky’ decision making.

The cognitive effects of active and sham repetitive transcranial magnetic stimulation (rTMS) were examined in 19 middle-aged and elderly patients with refractory depression. Patients received either active (n = 9) or sham (n = 10) rTMS targeted at the anterior portion of the left middle frontal gyrus. Patients in the active rTMS group improved significantly on a test of cognitive flexibility and conceptual tracking (Trail Making Test-B).

The epidemiological projections show that the problems of Mental Health were the main health challenge during the last decade. This situation is particularly worring in our region. The poor operative data in relation to the care of the mental disorders prevent the elaboration of plans on the basis of secure data. METHODOLOGY: Records of externation were analized during the period between 1994-1998 in the men Psychiatric Internation Unity in the Psychopatology Service of the Hospital Piñero in Buenos Aires, which is part of the public health service of the city. RESULTS: an average time of internation of 42.8 days was reported (SD 40,3), which was higher than the 11 days reported in institutions of the private health services. An increasing proportional diagnosis of Bipolar Disorder was reported (chi square corresponding to tendencies P<0.01, lineality P<0.001) and a significative decline in the number of diagnosis of Schizophrenia (chi square corresponding to tendencies P<0.05; lineality P<0.05). In this way, the ratio of the diagnosis of Schizophrenia and Bipolar Disorder changed from 7:1 in 1994 to 1,7:1 in 1998.

The modern concept of cycloid psychoses is primarily based upon the clinical delineation of their phenotypes according to Leonhard. By settling the dilemma of Kraepelinean «atypical psychoses «, their description may be considered one of the major achievements of clinical psychiatry in the last century. In particular, this had been facilitated by the work of Wernicke and Kleist. Albeit not yet generally recognized, cycloid psychoses have already stimulated great efforts of research yielding remarkable results. In this article, we elucidate the concept of cycloid psychoses and present recent findings pertaining to their putative biological foundations. Finally, future perspectives for the field of biological psychiatry are proposed fostering the heuristics of Leonhard’s nosology.

Lesions to prefrontal cortex (PFC) in humans can severely disrupt everyday decision-making, with concomitant effects on social and occupational functioning. Forty-six patients with unilateral lesions to prefrontal cortex and 21 healthy control subjects were administered three neuropsychological measures of decision-making: the Iowa Gambling Task, the Cambridge Gamble Task, and the Risk Task. Magnetic resonance imaging (MRI) scans were acquired from 40 patients, with region of interest (ROI) mapping of prefrontal subregions. The frontal patients showed only limited damage in medial and orbital prefrontal cortex, but greater damage in lateral prefrontal regions of interest. Patients with right frontal lesions preferred the risky decks on the Iowa Gambling Task, and differed significantly from left frontal and control subjects. Within the right frontal group, the preference for the risky decks was correlated with the total lesion volume and the volume of damage outside of the ventromedial prefrontal region. Right and left frontal groups did not differ significantly on the Cambridge Gamble Task or the Risk Task, and performance was not associated with lesion volume. The results indicate a laterality effect on the Iowa Gambling Task, and the contribution of prefrontal regions outside the ventromedial region to task performance. The Cambridge Gamble Task and Risk Task were less sensitive to the effects of unilateral frontal lobe lesions, and may be more selectively associated with ventral prefrontal damage.