Factors associated with poor functional outcome in bipolar disorder: sociodemographic, clinical, and neurocognitive variables.

OBJECTIVE: The current investigation aimed at studying the sociodemographic, clinical, and neuropsychological variables related to functional outcome in a sample of euthymic patients with bipolar disorder(BD) presenting moderate-severe levels of functional impairment. METHODS: Two-hundred and thirty-nine participants with BD disorders and with Functioning Assessment Short Test(FAST) scores equal or above 18 were administered a clinical and diagnostic interview, and the administration of mood measure scales and a comprehensive neuropsychological battery. Analyses involved preliminary Pearson bivariate correlations to identify sociodemographic and clinical variables associated with the FAST total score. Regarding neuropsychological variables, a principal component analysis (PCA) was performed to group the variables in orthogonal factors. Finally, a hierarchical multiple regression was run. RESULTS: The best fitting model for the variables associated with functioning was a linear combination of gender, age, estimated IQ, Hamilton Depression Rating Scale (HAM-D), number of previous manic episodes, Factor 1 and Factor 2 extracted from the PCA. The model, including all these previous variables, explained up to 29.4% of the observed variance. CONCLUSIONS: Male gender, older age, lower premorbid IQ, subdepressive symptoms, higher number of manic episodes, and lower performance in verbal memory, working memory, verbal fluency, and processing speed were associated with lower functioning in patients with BD.

Manual motor speed dysfunction as a neurocognitive endophenotype in euthymic bipolar disorder patients and their healthy relatives. Evidence from a 5-year follow-up study.

BACKGROUND: Few studies have examined Manual Motor Speed (MMS) in bipolar disorder (BD). The aim of this longitudinal, family study was to explore whether dysfunctional MMS represents a neurocognitive endophenotype of BD. METHODS: A sample of 291 subjects, including 131 BD patients, 77 healthy first-degree relatives (BD-Rel), and 83 genetically-unrelated healthy controls (HC), was assessed with the Finger-Tapping Test (FTT) on three occasions over a 5-year period. Dependence of FTT on participants´ age was removed by means of a lineal model of HC samples, while correcting simultaneously the time and learning effect. Differences between groups were evaluated with an ANOVA test. RESULTS: The patients' performance was significantly worse than that of HC over time (p≤0.006), and these deficits remained when non-euthymic BD patients (n=9) were excluded from analysis. Some significant differences between BD patients and BD-Rel (p≤0.037) and between BD-Rel and HC (p≤0.033) were found, but they tended to disappear as time progressed (p≥0.057). Performance of the BD-Rel group was intermediate to that of BD and HC. Most sociodemographic and clinical variables did not affect these results in patients. (p≥0.1). However, treatment with carbamazepine and benzodiazepines may exert a iatrogenic effect on MMS performance (p≤0.006). LIMITATIONS: Only right-handed subjects were included in this study. Substantial attrition over time was detected. CONCLUSIONS: There were significant differences between the patients´ MMS performance and that of healthy relatives and controls, regardless of most clinical and sociodemographic variables. Dysfunctional MMS could be considered an endophenotype of BD. Further studies are needed to rule out possible iatrogenic effects of some psychopharmacological treatments.

High cognitive reserve in bipolar disorders as a moderator of neurocognitive impairment.

BACKGROUND: Cognitive reserve (CR) reflects the capacity of the brain to endure neuropathology, minimize clinical manifestations and successfully complete cognitive tasks. The present study aims to determine whether high CR may constitute a moderator of cognitive functioning in bipolar disorder (BD). METHODS: 102 patients with BD and 32 healthy controls were enrolled. All patients met DSM-IV criteria for I or II BD and were euthymic (YMRS≤6 and HDRS≤8) during a 6-month period. All participants were tested with a comprehensive neuropsychological battery, and a Cerebral Reserve Score (CRS) was estimated. Subjects with a CRS below the group median were classified as having low CR, whereas participants with a CRS above the median value were considered to have high CR. RESULTS: Participants with BD with high CR displayed a better performance in measures of attention (digits forward: F=4.554, p=0.039); phonemic and semantic verbal fluency (FAS: F=9.328, p=0.004; and Animal Naming: F=8.532, p=0.006); and verbal memory (short cued recall of California Verbal Learning Test: F=4.236, p=0.046), after multivariable adjustment for potential confounders, including number of admissions and prior psychotic symptoms. LIMITATIONS: The cross-sectional design of the study does not allow the establishment of causal inferences. Additionally, the small size of the sample may have limited some results. CONCLUSIONS: High cognitive reserve may therefore be a valuable construct to explore for predicting neurocognitive performance in patients with BD regarding premorbid status.

Functional remediation in bipolar disorder: 1-year follow-up of neurocognitive and functional outcome.

BACKGROUND: Few randomised clinical trials have examined the efficacy of an intervention aimed at improving psychosocial functioning in bipolar disorder. AIMS: To examine changes in psychosocial functioning in a group that has been enrolled in a functional remediation programme 1 year after baseline. METHOD: This was a multicentre, randomised, rater-masked clinical trial comparing three patient groups: functional remediation, psychoeducation and treatment as usual over 1-year follow-up. The primary outcome was change in psychosocial functioning measured by means of the Functioning Assessment Short Test (FAST). Group×time effects for overall psychosocial functioning were examined using repeated-measures ANOVA (trial registration NCT01370668). RESULTS: There was a significant group×time interaction for overall psychosocial functioning, favouring patients in the functional remediation group (F = 3.071, d.f. = 2, P = 0.049). CONCLUSIONS: Improvement in psychosocial functioning is maintained after 1-year follow-up in patients with bipolar disorder receiving functional remediation.

Effects of functional remediation on neurocognitively impaired bipolar patients: enhancement of verbal memory.

BACKGROUND: Functional remediation is a novel intervention with demonstrated efficacy at improving functional outcome in euthymic bipolar patients. However, in a previous trial no significant changes in neurocognitive measures were detected. The objective of the present analysis was to test the efficacy of this therapy in the enhancement of neuropsychological functions in a subgroup of neurocognitively impaired bipolar patients. METHOD: A total of 188 out of 239 DSM-IV euthymic bipolar patients performing below two standard deviations from the mean of normative data in any neurocognitive test were included in this subanalysis. Repeated-measures analyses of variance were conducted to assess the impact of the treatment arms [functional remediation, psychoeducation, or treatment as usual (TAU)] on participants' neurocognitive and functional outcomes in the subgroup of neurocognitively impaired patients. RESULTS: Patients receiving functional remediation (n = 56) showed an improvement on delayed free recall when compared with the TAU (n = 63) and psychoeducation (n = 69) groups as shown by the group × time interaction at 6-month follow-up [F 2,158 = 3.37, degrees of freedom (df) = 2, p = 0.037]. However, Tukey post-hoc analyses revealed that functional remediation was only superior when compared with TAU (p = 0.04), but not with psychoeducation (p = 0.10). Finally, the patients in the functional remediation group also benefited from the treatment in terms of functional outcome (F 2,158 = 4.26, df = 2, p = 0.016). CONCLUSIONS: Functional remediation is effective at improving verbal memory and psychosocial functioning in a sample of neurocognitively impaired bipolar patients at 6-month follow-up. Neurocognitive enhancement may be one of the active ingredients of this novel intervention, and, specifically, verbal memory appears to be the most sensitive function that improves with functional remediation.

Trajectories of symptom dimensions in short-term response to antipsychotic treatment in patients with a first episode of non-affective psychosis.

BACKGROUND: Trajectory patterns of positive, disorganized and negative dimension symptoms during antipsychotic treatment in drug-naive patients with first-episode psychosis have yet to be examined by using naturalistic data. METHOD: This pragmatic clinical trial randomized 161 drug-naive patients with a first episode of psychosis to olanzapine, risperidone or haloperidol. Patients were assessed with the Scale for the Assessment of Negative Symptoms (SANS) and Positive Symptoms (SAPS) at baseline and at the end of weeks 1, 2, 3, 4 and 6 of antipsychotic treatment. Censored normal models of response trajectories were developed with three dimensions of the SAPS-SANS scores (positive, disorganized and negative) in order to identify the different response trajectories. Diagnosis, cannabis use, duration of untreated psychosis (DUP), smoking and antipsychotic class were examined as possible predictive variables. RESULTS: Patients were classified in five groups according to the positive dimension, three groups according to the disorganized dimension and five groups according to the negative dimension. Longer DUPs and cannabis use were associated with higher scores and poorer responses in the positive dimension. Cannabis use was associated with higher scores and poorer responses in the disorganized dimension. Only schizophrenia diagnosis was associated with higher scores and poorer responses in the negative dimension. CONCLUSIONS: Our results illustrate the heterogeneity of short-term response to antipsychotics in patients with a first episode of psychosis and highlight markedly different patterns of response in the positive, disorganized and negative dimensions. DUP, cannabis use and diagnosis appeared to have a prognostic value in predicting treatment response with different implications for each dimension.

The impact of repeated manic episodes and executive dysfunction on work adjustment in bipolar disorder.

The aim of this study was to study the clinical and neurocognitive variables that best explain poor work adjustment in a sample of bipolar I euthymic patients. Eighty-five euthymic patients at the Hospital Clinic of Barcelona were assessed for this study by means of a comprehensive neuropsychological battery and a work-focused interview to determine work adjustment. Clinical and sociodemographic variables were also collected. Direct logistic regression was performed to assess the impact of demographic, clinical and neuropsychological variables on the likelihood of presenting poor work adjustment. The model that best fitted contained five variables (Hamilton Depression Rating scores, number of manic episodes, number of perseverative errors in the Wisconsin Card Sorting Test (WCST), number of depressive episodes and Trail Making Test-part B). However, only two out of these variables made a unique statistically significant contribution to the model, which were number of manic episodes (OR 1.401; CI 1.05-1.86; p = 0.021) and number of perseverative errors in the WCST (OR 1.062; CI 1.00-1.12; p = 0.044). The model explained up to 36 % of the variance in work adjustment. This study highlights the role of manic relapses and neurocognitive impairment, specifically the role of executive function, in work adjustment.

The clinical implications of cognitive impairment and allostatic load in bipolar disorder.

BACKGROUND: Allostatic load (AL) relates to the neural and bodily "wear and tear" that emerge in the context of chronic stress. This paper aims to provide clinicians with a comprehensive overview of the role of AL in patophysiology of bipolar disorder (BD) and its practical implications. METHODS: PubMed searches were conducted on English-language articles published from 1970 to June 2011 using the search terms allostatic load, oxidative stress, staging, and bipolar disorder cross-referenced with cognitive impairment, comorbidity, mediators, prevention. RESULTS: Progressive neural and physical dysfunction consequent to mood episodes in BD can be construed as a cumulative state of AL. The concept of AL can help to reconcile cognitive impairment and increased rates of clinical comorbidities that occur over the course of cumulative BD episodes. CONCLUSIONS: Data on transduction of psychosocial stress into the neurobiology of mood episodes converges to the concept of AL. Mood episodes prevention would not only alleviate emotional suffering, but also arrest the cycle of AL, cognitive decline, physical morbidities and, eventually, related mortality. These objectives can be achieved by focusing on effective prophylaxis from the first stages of the disorder, providing mood-stabilizing agents and standardized psychoeducation and, potentially, addressing cognitive deficits by the means of specific medication and neuropsychological interventions.

Neurocognitive impairment across the bipolar spectrum.

Bipolar disorder is a severe mental illness that affects nearly 4.4% of the general population when bipolar spectrum disorders are taken into account. Neurocognitive impairment is thought to be a core deficit of this illness since it is present during euthymia. In fact, 40-60% of euthymic patients present with neurocognitive disturbances. Not only the clinical factors but also disturbances in neurocognition can influence the functional outcome of BD patients. Hence, further research is needed in order to clarify the relationship between these variables. Despite the growing body of evidence that has emerged during the last decade, no unique neurocognitive profile has been proposed yet for either BD subtype. The majority of the studies recluted heterogeneous samples (including both bipolar I and II) or focused on BD-I patients only. The aim of this review is to give an overall picture of the main neurocognitive disturbances found in the bipolar spectrum and particularly in BD-II, where the findings are more ambiguous. An extensive review of all the literature has been done regarding this subtype (from 1980 until July 2009). Data available until now suggest that deficits are present across the bipolar spectrum (BD-I and BD-II), but they seem slightly more severe in BD-I. The extent to which either subtype share-or not-some similarities is still unknown. More studies are required but it would also be interesting to reach a consensus in the neuropsychological assessment of BD to facilitate comparisons between the different studies.

Neurocognitive impairment and psychosocial functioning in bipolar II disorder.

OBJECTIVE: There is a growing body of evidence on neurocognitive impairment in euthymic bipolar patients, but this issue has been studied mostly in bipolar I disorder, data on bipolar II (BD-II) are scant and discrepant. The two aims of this study were to ascertain whether strictly defined euthymic BD-II patients would present neurocognitive disturbances and to evaluate their impact on functional outcome. METHOD: Forty-three BD-II patients and 42 demographically and educationally matched healthy subjects were assessed with a comprehensive neuropsychological test battery and with the Social and Occupational Functioning Assessment Scale (SOFAS). The euthymia criteria were reduced (Hamilton Rating Scale for Depression score ≤6 and a Young Mania Rating Scale score ≤6) to minimize the influence of subdepressive symptomatology on cognition and functioning. RESULTS: BD-II patients showed a significantly lower performance on several measures of attention, learning and verbal memory, and executive function compared with healthy controls. The presence of subthreshold depressive symptomatology and one measure related to executive function (Trail Making Test, part B) was the variables that best predicted psychosocial functioning measured with the SOFAS. CONCLUSION: This report provides further evidence that euthymic BD-II patients present cognitive impairment which may impact psychosocial functioning.

Global and regional cortical thinning in first-episode psychosis patients: relationships with clinical and cognitive features.

BACKGROUND: The thickness of the cortical mantle is a sensitive measure for identifying alterations in cortical structure. We aimed to explore whether first episode schizophrenia patients already show a significant cortical thinning and whether cortical thickness anomalies may significantly influence clinical and cognitive features. METHOD: We investigated regional changes in cortical thickness in a large and heterogeneous sample of schizophrenia spectrum patients (n=142) at their first break of the illness and healthy controls (n=83). Magnetic resonance imaging brain scans (1.5 T) were obtained and images were analyzed by using brains2. The contribution of sociodemographic, cognitive and clinical characterictics was investigated. RESULTS: Patients showed a significant total cortical thinning (F=17.55, d=-0.62, p<0.001) and there was a diffuse pattern of reduced thickness (encompassing frontal, temporal and parietal cortices) (all p's<0.001, d's>0.53). No significant group×gender interactions were observed (all p's>0.15). There were no significant associations between the clinical and pre-morbid variables and cortical thickness measurements (all r's<0.12). A weak significant negative correlation between attention and total (r=-0.24, p=0.021) and parietal cortical thickness (r=-0.27, p=0.009) was found in patients (thicker cortex was associated with lower attention). Our data revealed a similar pattern of cortical thickness changes related to age in patients and controls. CONCLUSIONS: Cortical thinning is independent of gender, age, age of onset and duration of the illness and does not seem to significantly influence clinical and functional symptomatology. These findings support a primary neurodevelopment disorder affecting the normal cerebral cortex development in schizophrenia.

Functional impairment in bipolar II disorder: is it as disabling as bipolar I?

INTRODUCTION: It is well established that patients with bipolar disorder experience functional impairment even in remission. Nevertheless, bipolar II disorder remains understudied because most investigations to date include only bipolar I patients or just a small sample of bipolar II patients, without explicitly comparing both subtypes of disorder. The main objective of the current report is to evaluate overall and multiple domains of functioning, specifically in bipolar II disorder compared to patients with bipolar I disorder and healthy subjects. METHODS: 233 subjects from 3 groups were compared: bipolar I patients (n=106), bipolar II patients (n=66) and healthy controls (n=61). Bipolar patients meeting criteria of remission were recruited at the Hospital Clinic of Barcelona and at different study sites in Argentina. All participants were assessed with 17-item Hamilton Depression Rating Scale (HAM-D), Young Mania Rating Scale (YMRS) and the Functioning Assessment Short Test (FAST). Clinical and sociodemographic data were also recorded. RESULTS: Both subgroups of patients, bipolar I and bipolar II, showed lower overall functioning (p<0.001) and in each domain of the FAST scale (all, p<0.001) when compared to the healthy control group. Tukey post hoc test revealed that bipolar II patients scored worse in the cognitive domain compared to bipolar I patients. However, after controlling for potential confounding variables, this difference disappeared and only older age (p<0.005) and HAM-D scores (p<0.001) remained significant. CONCLUSIONS: Our results suggest that bipolar II patients are as disabled as bipolar I patients. This may be explained, in part, because bipolar II patients experience greater lifetime residual depressive symptoms than the bipolar I subgroup, which may have particular impact on cognitive domains of functioning.

Motor speed predicts stability of cognitive deficitsin both schizophrenic and bipolar I patients at oneyearfollow-up

Background: We examined whether motor speed assessed by the fingertapping test predicts generalized and specific stable deficits because of a common pathogenicprocess in bipolar and schizophrenic patients.Methods: One hundred and two patients underwent a battery of neuropsychologicaltests. Patients with a score of less than one standard deviation from their siblings’ samplein two assessments with an interval of one year were defined as suffering from stabledeficits because of a common pathogenic process. In addition to univariate analyses, factoranalyses, ordinal logistic regression, and multiple linear regressions were used. A generalscore was also calculated. Results: No differences were found between schizophrenic and bipolar patients in thedeficits of verbal fluency, shift reasoning ability and executive attention. Schizophrenicpatients had greater persistent cognitive deficit because of a common pathogenic factor inthe verbal memory dimension than bipolar patients. Motor speed predicted the specificdeficits of verbal fluency, shift reasoning, executive attention and the general deficit ofboth bipolar I and schizophrenic patients. Bipolar patients suffered a lesser specific deficitin the verbal memory dimension than schizophrenic patients did, this domain not beingpredicted by motor speed. Motor speed predicted the generalized deficit and the specificdimensions in which schizophrenic and bipolar patients showed no differences.Conclusions: These results suggest the presence of general and specific stable cognitivedeficits because of a common pathogenic factor related to psychomotor slowness. Motorspeed seems to be suitable endophenocognitype for schizophrenia and bipolar disorder (AU)

Functioning and disability in bipolar disorder: an extensive review.

BACKGROUND: Bipolar disorder has generally been regarded as having a better functional outcome than schizophrenia. However, studies have suggested low functioning in bipolar patients even when they are in clinical remission. Our aim was to determine the degree of functioning and disability in bipolar patients. Secondly, we reviewed factors potentially associated with the low functioning of bipolar patients. METHOD: The authors conducted an extensive Medline and Pubmed search of the published literature from 1980 up to December 2007, using a variety of search terms to find relevant articles. Bibliographies of retrieved papers were further analysed for publications of interest. Articles that reported clinically significant findings on functioning and disability, and research reports were reviewed in detail. RESULTS: From these articles, we determined that bipolar disorder is associated with significant impairment in work, family and social life, beyond the acute phases of the illness. The aspects that appear to increase the risk of low functioning and disability in bipolar patients are mainly subsyndromal symptoms and neurocognitive impairment, among others. CONCLUSIONS: Suitable pharmacological and psychological interventions may improve the level of functioning and reduce the disability in bipolar patients. Potential targets to be considered for intervention should be residual symptoms, comorbid conditions and neurocognitive deficits. Further research is required to better identify the factors that best predict functioning in bipolar patients.

Chromosome 8p as a potential hub for developmental neuropsychiatric disorders: implications for schizophrenia, autism and cancer.

Defects in genetic and developmental processes are thought to contribute susceptibility to autism and schizophrenia. Presumably, owing to etiological complexity identifying susceptibility genes and abnormalities in the development has been difficult. However, the importance of genes within chromosomal 8p region for neuropsychiatric disorders and cancer is well established. There are 484 annotated genes located on 8p; many are most likely oncogenes and tumor-suppressor genes. Molecular genetics and developmental studies have identified 21 genes in this region (ADRA1A, ARHGEF10, CHRNA2, CHRNA6, CHRNB3, DKK4, DPYSL2, EGR3, FGF17, FGF20, FGFR1, FZD3, LDL, NAT2, NEF3, NRG1, PCM1, PLAT, PPP3CC, SFRP1 and VMAT1/SLC18A1) that are most likely to contribute to neuropsychiatric disorders (schizophrenia, autism, bipolar disorder and depression), neurodegenerative disorders (Parkinson's and Alzheimer's disease) and cancer. Furthermore, at least seven nonprotein-coding RNAs (microRNAs) are located at 8p. Structural variants on 8p, such as copy number variants, microdeletions or microduplications, might also contribute to autism, schizophrenia and other human diseases including cancer. In this review, we consider the current state of evidence from cytogenetic, linkage, association, gene expression and endophenotyping studies for the role of these 8p genes in neuropsychiatric disease. We also describe how a mutation in an 8p gene (Fgf17) results in a mouse with deficits in specific components of social behavior and a reduction in its dorsomedial prefrontal cortex. We finish by discussing the biological connections of 8p with respect to neuropsychiatric disorders and cancer, despite the shortcomings of this evidence.

Cognitive impairment in schizoaffective disorder: a comparison with non-psychotic bipolar and healthy subjects.

OBJECTIVE: Only a few studies have examined specifically the neuropsychological performance of schizoaffective patients. METHOD: The sample consisted of 34 euthymic DSM-IV schizoaffective patients, who were compared with 41 euthymic bipolar patients without history of psychotic symptoms and 35 healthy controls. Euthymia was defined by a score of 6 or less at the Young Mania Rating Scale and a score of 8 or less at the Hamilton Depression Rating Scale for at least 6 months. Patients were compared with several clinical, occupational, and neuropsychological variables such as executive function, attention, verbal and visual memory and the two groups were contrasted with 35 healthy controls on cognitive performance. The three groups were compared using mancova after checking the potential role of several co-variables. RESULTS: Schizoaffective patients showed greater impairment than controls and bipolar patients, in several domains, including verbal memory, executive function, and attentional measures. Bipolar patients without history of psychosis performed similar to the controls except for verbal fluency. CONCLUSION: Schizoaffective disorder carries more neurocognitive impairment than non-psychotic bipolar disorder and more occupational difficulties.

Functional outcome in bipolar disorder: the role of clinical and cognitive factors.

INTRODUCTION: Few studies have examined the clinical, neuropsychological and pharmacological factors involved in the functional outcome of bipolar disorder despite the gap between clinical and functional recovery. METHODS: A sample of 77 euthymic bipolar patients were included in the study. Using an a priori definition of low versus good functional outcome, based on the psychosocial items of the Global Assessment of Functioning (GAF, DSM-IV), and taking also into account their occupational adaptation, the patients were divided into two groups: good or low occupational functioning. Patients with high (n = 46) and low (n = 31) functioning were compared on several clinical, neuropsychological and pharmacological variables and the two patient groups were contrasted with healthy controls (n = 35) on cognitive performance. RESULTS: High- and low-functioning groups did not differ with respect to clinical variables. However, bipolar patients in general showed poorer cognitive performance than healthy controls. This was most evident in low-functioning patients and in particular on verbal memory and executive function measures. CONCLUSIONS: Low-functioning patients were cognitively more impaired than highly functioning patients on verbal recall and executive functions. The variable that best predicted psychosocial functioning in bipolar patients was verbal memory.

Variations in genes regulating neuronal migration predict reduced prefrontal cognition in schizophrenia and bipolar subjects from mediterranean Spain: a preliminary study.

Both neural development and prefrontal cortex function are known to be abnormal in schizophrenia and bipolar disorder. In order to test the hypothesis that these features may be related with genes that regulate neuronal migration, we analyzed two genomic regions: the lissencephaly critical region (chromosome 17p) encompassing the LIS1 gene and which is involved in human lissencephaly; and the genes related to the platelet-activating-factor, functionally related to LIS1, in 52 schizophrenic patients, 36 bipolar I patients and 65 normal control subjects. In addition, all patients and the 25 control subjects completed a neuropsychological battery. Thirteen (14.8%) patients showed genetic variations in either two markers related with lissencephaly or in the platelet-activating-factor receptor gene. These patients performed significantly worse in the Wisconsin Card Sorting Test-Perseverative Errors in comparison with patients with no lissencephaly critical region/platelet-activating-factor receptor variations. The presence of lissencephaly critical region/platelet-activating-factor receptor variations was parametrically related to perseverative errors, and this accounted for 17% of the variance (P = 0.0001). Finally, logistic regression showed that poor Wisconsin Card Sorting Test-Perseverative Errors performance was the only predictor of belonging to the positive lissencephaly critical region/platelet-activating-factor receptor group. These preliminary findings suggest that the variations in genes involved in neuronal migration predict the severity of the prefrontal cognitive deficits in both disorders.

Recall and recognition confabulation in psychotic and bipolar disorders: evidence for two different types without unitary mechanisms.

Several forms of confabulation have been identified recently in schizophrenic patients, but it has not yet been investigated whether these forms are specific to schizophrenia. Furthermore, the origin of confabulation is unclear. The present study investigated recall and recognition confabulation and their relations with symptomatology, cognitive domains (abstraction and flexibility, verbal fluency, verbal memory, motor activity, and visual-motor processing/attention), computed tomographic (CT) measures (ventricular, cerebral, and Sylvian fissure size), and auditory event-related potentials (amplitudes and latencies of peak components in oddball paradigms) in 33 schizophrenic patients, 35 bipolar I patients, eight schizoaffective patients, and seven patients with other psychotic disorders. We found that neither type of confabulation was specific of any diagnostic group. Recall confabulation was mainly predicted by the predominance of positive symptoms, while recognition confabulation was predicted by a delay in P300 latency and the doses of antipsychotics used. Our results suggest two different mechanisms for both types of confabulation based on interference with the adequate retrieval of information and slowness in early stimulus detection.

Preferencia motora y esquizofrenia (II) / Motor preferency and schizophrenia (II)

Este artículo corresponde a la segunda parte de una revisión de la literatura sobre preferencia manual y esquizofrenia. A pesar de la falta de datos definitivos, el mayor número de trabajos apuntan a que en la esquizofrenia existe una alteración del patrón normal de preferencia manual, con un incremento de los zurdos o nodiestros. Se describen las asociaciones entre preferencia manual y las distintas variables clínicas de la esquizofrenia. Al final, se discuten las implicaciones de estos estudios en la etiología biológica de la esquizofrenia. En cualquier caso, parece evidente la importancia de conocer esta variable en los pacientes esquizofrénicos, dentro del contexto de la práctica clínica y de la investigación básica (AU)