The Relationship Between IQ, Memory, Executive Function, and Processing Speed in Recent-Onset Psychosis: 1-Year Stability and Clinical Outcome

Studies commonly report poor performance in psychotic patients compared with controls on tasks testing a range of cognitive functions, but, because current IQ is often not matched between these groups, it is difficult to determine whether this represents a generalized deficit or specific abnormalities. Fifty-three first-episode psychosis patients and 53 healthy controls, one-to-one matched for sex, age, and full-scale current IQ, were compared on Wechsler Adult Intelligence Scale (WAIS) subtests representing indices of perceptual organization, verbal comprehension, processing speed, and working memory as well as other tests of executive function and episodic memory. The groups showed an equivalent pattern of performance on all WAIS subtests except digit symbol processing speed, on which the patients were significantly worse. Patients were also worse on measures where performance correlated with digit symbol score, namely working and verbal memory tasks. Standardized residual scores for each subtest were calculated for each patient using the difference between their actual subtest score and a predicted subtest score based on their full-scale IQ and the performance of controls. Scaled scores and residual scores were examined for relationships with clinical measures. Digit symbol–scaled score was significantly correlated with concurrent negative syndrome score at baseline, and digit symbol residual score significantly predicted residual negative symptoms at 1-year follow-up. In summary, our comparison of patients and controls precisely matched for IQ revealed that processing speed was attenuated in recent-onset schizophrenia, contributed significantly to working and episodic memory deficits, and was a prognostic factor for poor outcome at 1 year

Psychomotor slowing and planning deficits in schizophrenia

Contains fulltext : 64392.pdf (publisher's version ) (Open Access)RU Radboud Universiteit Nijmegen, 01 juli 2004Promotor : Hulstijn, W.164 p

Planningsstoornissen bij schizofrenie. Nieuwe grafische onderzoeksmethoden

Contains fulltext : 62291.pdf (publisher's version ) (Open Access)Veel patiënten met schizofrenie vertonen gedrag dat veroorzaakt wordt door een gebrekkige planning van alledaagse handelingen. De aard van deze stoornis kan onderzocht worden met cognitief-neuropsychologische onderzoeksmethoden, waarin eenvoudige figuren gekopieerd moeten worden waarbij gelijktijdig digitale bewegingsregistratie plaatsvindt. Recente voorbeelden van dit onderzoek worden beschreven. Daaruit komt naar voren dat patiënten met schizofrenie een gebrekkige 'impliciete' planning vertonen. De gebruikte grafische onderzoeksmethoden vormen dus een interessante aanvulling op bestaande tests voor expliciete planning

Is the planning of action more impaired in schizophrenic patients than in depressed patients? The effects of conflicting graphic production rules

Item does not contain fulltextThe present study examined the question whether the (im)possibility of applying graphic productions rules would influence the speed of copying simply patterns in schizophrenic and depressed patients. It was hypothesized that because of a lack of planning schizophrenic patients would show fewer differences between copying 'non-conflicting' patterns (in which rules can be applied) and 'conflicting' patterns (in which rules have to be violated) when compared to depressed patients and controls. The results generally confirmed these predictions, in that differences between non-conflicting and conflicting patterns were only found in depressed patients and controls. This opens a new way for the study of planning deficits in schizophrenia.305 p

Movement planning deficits in schizophrenia: Failure to inhibite automatic response tendencies

Contains fulltext : 56398.pdf (publisher's version ) (Closed access)Abstract Introduction. Explicit planning deficits have been reported frequently in patients with schizophrenia. This study addressed the question whether these patients would already encounter difficulties in a more “implicit” process of planning an optimal sequence of movements in simple actions. Methods . Twenty patients with schizophrenia and 20 controls participated in the study. The motor tasks consisted of copying simple line drawings in which the planning of a movement sequence was taxed along various dimensions. In the first task the number of line elements varied between one and two, and the two-line figures differed with respect to the ease with which the so-called graphic production rules could be applied. In the second task the spatial position of the drawing varied between an easy centre position and a somewhat more difficult corner location. In the third task, subjects were asked to start copying either at a preferred or at a less preferred starting point. Results. The results showed that the patients did not encounter planning difficulties while copying the one- or two-segment patterns. However, the variations in the spatial conditions and starting point did affect the patients' performance more than that of the controls. Whereas the patients with higher negative symptom scores tended to be slower when they were forced to start drawing at a particular point, the patients predominantly exhibiting features of disorganisation proved to be faster in this condition. Conclusions. The findings suggest a fairly intact initiation of simple movement sequences in patients with schizophrenia, but difficulties in inhibiting automatic response tendencies. It is concluded that this inhibition failure may play an important role in the planning difficulties these patients experience.18 p

Planningsstoornissen bij schizofrenie. Nieuwe grafische onderzoeksmethoden

Veel patiënten met schizofrenie vertonen gedrag dat veroorzaakt wordt door een gebrekkige planning van alledaagse handelingen. De aard van deze stoornis kan onderzocht worden met cognitief-neuropsychologische onderzoeksmethoden, waarin eenvoudige figuren gekopieerd moeten worden waarbij gelijktijdig digitale bewegingsregistratie plaatsvindt. Recente voorbeelden van dit onderzoek worden beschreven. Daaruit komt naar voren dat patiënten met schizofrenie een gebrekkige 'impliciete' planning vertonen. De gebruikte grafische onderzoeksmethoden vormen dus een interessante aanvulling op bestaande tests voor expliciete planning

Studying planning in patients with schizophrenia by means of simple figure-copying tasks

Item does not contain fulltext1 p

Basal cortisol and DHEA levels in women with borderline personality disorder

Previous research suggests that in borderline personality disorder (BPD) normal stress regulation, with a main role for cortisol, is disturbed. However, most studies were confounded by their lack of attention to co-morbidity. Relevant patient characteristics such as depression, childhood abuse, posttraumatic stress disorder (PTSD) and copying styles were not systematically examined. Moreover, none of the studies incorporated dehydroepiandrosterone (DHEA), a hormone that can antagonize the effects of cortisol. Hence, the present pilot study investigates the basic levels of cortisol and DHEA and the ratio (CDR) between the two hormones in BPD patients. Twenty-two women with BPD and 22 healthy female controls provided two diurnal (8 a.m./8 p.m.) salivary samples. Overall cortisol levels were not significantly increased in the patient group as a whole but only in those patients diagnosed with co-morbid PTSD and a history of childhood abuse. The patients’ cortisol secretions decreased relatively less steep during the day than it did in the controls. Surprisingly, morning DHEA levels were significantly higher in the patients than in the controls. Moreover, the CDR showed a significantly larger and less favourable increase in the BPD group during the day. In the patients lower levels of DHEA in the evening proved significantly related to a stronger tendency to avoid active problem solving and a lowered inclination to seek social support. The current findings underline the relevance of cortisol and DHEA assessments and the need for further scrutiny of their interplay to foster our understanding of the biological basis of stress regulation in BPD