Charles Cotrena

Executive function impairments in depression and bipolar disorder: association with functional impairment and quality of life

BACKGROUND The neuropsychological correlates of major depressive (MDD) and bipolar disorder (BD), and their association with quality of life (QOL) and functioning, have not been sufficiently studied in the literature. The present study aimed to compare executive functions, attention, processing speed, QOL and disability between patients with BD type I, BD type II, MDD and healthy controls. METHOD 205 participants (n=37 BDI, 81% female; n=35 BDII, 80% female; n=45 MDD, 69% female; n=89C, 46% female) aged between 18 and 67 years were administered an extensive neurocognitive battery consisting of widely used standardized measures such as the Trail Making Test, the Stroop Color-Word Test and a modified version of the Wisconsin Card Sorting Task. Z-scores were compared between groups by ANCOVA. The prevalence of impairments on each measure (Z-score<1.5) was compared between groups using chi-square tests. The associations between cognition, quality of life and functioning were evaluated through correlational analysis. RESULTS Patients with MDD showed poor selective and sustained attention, and exhibited impairments in timed tasks, suggesting low efficiency of executive processing. Patients with BDI displayed more widespread cognitive impairment than the remaining groups, and performed worse than subjects with MDD on measures of sustained attention and inhibitory control. Decision-making ability and attentional control were able to distinguish between patients with BDI and BDII. QOL and disability were most impaired in patients with BDI, and more closely associated with cognitive impairment than in the remaining groups. LIMITATIONS No control of pharmacological variables, clinical or demographic characteristics. CONCLUSIONS Our results provide important information regarding the nature and severity of the cognitive alterations associated with different mood disorders, and may contribute to the diagnosis, rehabilitation and treatment of these conditions.

Estudo de fidedignidade do instrumento neuropsicológico Iowa Gambling Task

OBJECTIVE: This study aimed at evaluating reliability evidence of neuropsychological instrument Iowa Gambling Task (IGT) by the means of the test-retest method. METHOD: The sample was comprised of 50 healthy subjects, 19-75 years of age, with at least five years of formal education. The assessment was done individually, in two meetings with an interval from 1 to 6 months between test and retest. RESULTS: The findings showed a significant moderate positive correlation between test-retest in the overall calculation. In the analysis by segments, a significant moderate positive correlation was found for blocks 4 and 5, whereas there were no significant correlations for blocks 1, 2 and 3. CONCLUSION: These data corroborate recent studies that found moderate correlations between test-retest measures of executive functions, and suggest that the IGT can be used to assess decision making over time if specific analyses are taken into account.

Quality of life, functioning and cognition in bipolar disorder and major depression: A latent profile analysis

This study aimed to identify profiles of functioning and quality of life (QOL) in depression (MDD), bipolar disorder (BD) and healthy adults, as well as the clinical, demographic and cognitive variables associated with each of these profiles. Participants completed the WHODAS 2.0 and WHOQOL-BREF, which were submitted to latent profile analysis. The four cluster solution provided the best fit for our data. Cluster 1 consisted mostly of healthy adults, and had the highest functioning and QOL. Clusters 2 contained older patients with subclinical depressive symptoms and psychiatric comorbidities, whose impairments in QOL and functioning were associated with mood symptoms and several cognitive abilities. Patients with MDD, BDI or BDII with mild to moderate depression, such as those in cluster 3, may benefit more significantly from interventions in cognitive flexibility, inhibition, planning, and sustained attention. Lastly, patients with mood disorders and clinically significant levels of depression, as well as a history of suicide attempts, like those in cluster 4, may benefit from interventions aimed at working memory, inhibitory control, and cognitive flexibility; that is, the three core executive functions. These findings should be further investigated, and used to guide treatments for patients with mood disorders and different patterns of functional impairment.

Impaired decision-making after traumatic brain injury: The Iowa Gambling Task

Abstract Summary: The aim of the present study was to use the Iowa Gambling Task (IGT) to investigate differences in decision-making (DM) between patients who sustained TBI and healthy subjects, while controlling for age, education and gender. Methods: A hundred and ten participants, half of whom had severe or mild TBI, completed the IGT. Results: Differences between control participants and patients with TBI were found regarding total net score, block score, number of selections from each deck and classification of performance as impaired or unimpaired. No significant differences in IGT performance were found between patients with and without frontal lesions and between patients with mild and severe TBI. Conclusions: Results indicate poor DM on the IGT in patients with TBI, regardless of lesion location and severity. The instrument proved to be equally sensitive to both frontal and extrafrontal lesions and did not differentiate between patients with mild and severe TBI.

The impact of frontal and cerebellar lesions on decision making: evidence from the Iowa Gambling Task

Although the frontal lobes have traditionally been considered the neural substrates of executive functioning (EF), recent studies have suggested that other structures, such as the cerebellum, may be associated with these abilities. The role of the cerebellum has only been sparsely investigated in connection with decision making (DM), an important component of EF, and the few results obtained on this front have been inconclusive. The current study sought to investigate the role of the cerebellum in DM by comparing the performance of patients with cerebellar strokes, frontal-damaged patients, and a healthy control group on the Iowa Gambling Task (IGT). A total of nine cerebellar-damaged adults participated in the study, as well as nine individuals with frontal strokes and 18 control individuals. Patients were administered a version of the IGT adapted to the population of Southern Brazil. There was a marginal difference in mean IGT net scores between the two clinical groups, although both displayed impaired performance as compared to the control group. Overall, the DM ability of patients with cerebellar damage proved to be more preserved than that of individuals with frontal lobe strokes, but less preserved than that of the control group. These data suggested that, while the frontal lobes may be the most important brain structures for DM, the cerebellum might also play an active role in this cognitive function. Future studies assessing participants with lesions in different cerebellar regions and hemispheres will prove invaluable for the understanding of the neural structures involved in DM, and make significant contributions to the globalist-localizationist debate in DM neuroscience.

The Predictive Impact of Biological and Sociocultural Factors on Executive Processing: The Role of Age, Education, and Frequency of Reading and Writing Habits

Although the impact of education and age on executive functions (EF) has been widely studied, the influence of daily cognitive stimulation on EF has not been sufficiently investigated. Therefore, the aim of the present study was to evaluate whether the age, education, and frequency of reading and writing habits (FRWH) of healthy adults could predict their performance on measures of inhibition and cognitive flexibility. Inhibition speed, inhibitory control, and set shifting were assessed using speed, accuracy, and discrepancy scores on the Trail-Making Test (TMT) and Hayling Test. Demographic characteristics and the FRWH were assessed using specialized questionnaires. Regression analyses showed that age and the FRWH predicted speed and accuracy on the TMT. The FRWH predicted both speed and accuracy on the Hayling Test, for which speed and accuracy scores were also partly explained by age and education, respectively. Surprisingly, only the FRWH was associated with Hayling Test discrepancy scores, considered one of the purest EF measures. This highlights the importance of regular cognitive stimulation over the number of years of formal education on EF tasks. Further studies are required to investigate the role of the FRWH so as to better comprehend its relationship with EF and general cognition.

Verbal and visuospatial executive functions in healthy elderly: The impact of education and frequency of reading and writing

Objective To assess the predictive role of education and frequency of reading and writing habits (FRWH) on the cognitive flexibility, inhibition and planning abilities of healthy elderly individuals. Methods Fifty-seven healthy adults aged between 60 and 75 years with 2 to 23 years of formal education were assessed as to the frequency with which they read and wrote different types of text, as well as their number of years of formal education. Executive functions were evaluated using the Hayling Test and the Modified Wisconsin Card Sorting Test (MWCST). Results Weak to moderate positive correlations were found between education, FRWH and the number of categories completed in the MWCST, while negative correlations were identified between these variables and the number of perseverative and non-perseverative errors on the task. Only the FRWH was significantly correlated with the number of failures to maintain set. Speed and accuracy on the Hayling Test were only correlated with participant education. Both education and FRWH significantly predicted performance on the MWCST, and the combination of these two variables had a greater predictive impact on performance on this task than either of the two variables alone. Variability in scores on the Hayling Test was best accounted for by participant education. Conclusion In this sample of elderly subjects, cognitive flexibility was sufficiently preserved to allow for adequate performance on verbal tasks, but may have benefitted from the additional stimulation provided by regular reading and writing habits and by formal education in the performance of more complex non-verbal tasks.

Self-reported inhibition predicts history of suicide attempts in bipolar disorder and major depression

BACKGROUND Studies have reliably identified an association between suicide attempts and executive functions such as decision making (DM) and inhibitory control (IC) in patients with mood disorders. As such, the present study aimed to investigate the association between inhibition, DM, impulsivity and the history of suicide attempts in individuals with bipolar (BD) or major depressive disorder (MDD), identifying which assessment instruments may be most strongly associated with suicide in clinical samples. METHODS The sample included 80 control subjects and two groups of patients with BD and MDD, matched by age and education (26 with a history of suicide attempts [MD+], and 26 with no such history [MD-]). Participants completed behavioral and self-report measures of DM and IC, which were compared between groups using ANCOVA, followed by logistic regression for patients with mood disorders only, and the presence or absence of a history of suicide as the outcome. RESULTS Cognitive performance did not differ between groups. The MD+ group showed significantly higher motor and attentional impulsivity on the BIS-11 than the MD- and control groups. A regression analysis containing these scores showed that motor impulsivity was the only significant predictor of a history of suicide (OR = 1.14; 95%CI 1.00-1.30). CONCLUSIONS Self-reported motor impulsivity was a significant predictor of suicide. These findings underscore the importance of self-report measures in neuropsychological assessment, and their contributions to the management and prognosis of patients with mood disorders. Lastly, they point to the role of impulsivity as a target for interventions and public policy on suicide prevention.

Adaptation and validation of the Melbourne Decision Making Questionnaire to Brazilian Portuguese

INTRODUCTION Decision making (DM) is among the most important abilities for everyday functioning. However, the most widely used measures of DM come from behavioral paradigms, whose ecological validity and standalone use has been criticized in the literature. Though these issues could be addressed by the use of DM questionnaires as a complementary assessment method, no such instruments have been validated for use in Brazilian Portuguese. Therefore, the aim of this study was to conduct the translation and validation of the Melbourne Decision Making Questionnaire (MDMQ) for use in a Brazilian population. METHODS The adaptation of the MDMQ involved the following steps: translation, back-translation, expert review and pilot study. These steps were followed by factor analysis and internal consistency measurements, which led to the exclusion of 4 items from the scale. The 18-item version of the MDMQ was then administered to a validation sample consisting of healthy adults, as well as patients with bipolar disorder (BD) and major depressive disorder (MDD). RESULTS The instrument displayed good internal consistency, with the hypervigilance subscale showing the lowest, though still acceptable, Cronbachs alpha value. Its factor structure was comparable to that of the original MDMQ according to confirmatory factor analysis. Nevertheless, the MDMQ was sensitive to both depression severity and the presence of MDD and BD, both of which are known to have an impact on DM ability. CONCLUSION The version of the MDMQ produced in the present study may be an important addition to neuropsychological assessment batteries with a focus on DM and related abilities.

The predictive role of daily cognitive stimulation on executive functions in bipolar disorder

This study aimed to estimate the predictive role of clinical and demographic variables on the three core executive functions (EF) - working memory (WM), inhibitory control (IC) and cognitive flexibility (CF) - in bipolar disorder (BD). The sample consisted of 38 patients with BD type I, 39 with BD type II, and 106 control participants with no mood disorders. Subjects completed the Hayling Test, Trail Making Test, Digit Span Backwards, Sentence Word Span Test, and Stroop Color-Word Test. Composite scores for WM, IC and CF were calculated, and their correlations with clinical and demographic variables were analyzed. Stepwise hierarchical regression models including all significant correlates, gender, and diagnosis, revealed that the frequency of reading and writing habits (FRWH), IQ and diagnosis predicted 38.1% of the variance in IC. Diagnosis and IQ predicted 24.9% of the variance in WM scores. CF was predicted by the FRWH only, which accounted for 7.6% of the variance in this construct. These results suggest that daily cognitive stimulation through reading and writing make a significant positive contribution to executive functioning in BD, even in the absence of continued education. These and other forms of routine cognitive stimulation should be further emphasized in intervention programs for BD.