Emotional processing subtypes in bipolar disorder: A cluster analysis.

BACKGROUND: Evidence regarding the performance of Bipolar Disorder patients (BD) on Emotional Processing (EP) is conflicting, suggesting that heterogeneity within this population may exist. It is not completely understood if this impacts on clinical presentation and functional outcomes. METHODS: A total of 212 BD patients were recruited. Patients underwent MATRICS Consensus Cognitive Battery as well as a clinical evaluation to detect premorbid traits, comorbidities and clinical features. Performance on each basic emotion on the Emotional Recognition Task (ERT) and Reading the Mind in the Eyes Test were entered into hierarchical cluster analyses in order to determine the number of clusters and to assign subjects to specific clusters. We then compared subgroups on clinical factors and real-world community functioning. RESULTS: No differences between BD patients as a group and controls were found in EP performance. Two clusters of BD patients were found, one with "intact" performance (71.2%) that performed as healthy controls (HC) and other with "impaired" performance (28.8%) performing worse than HC and schizophrenic patients on basic emotion recognition. Patients in the "impaired group" presented higher rates of childhood trauma, schizotypal traits, lower premorbid IQ and education, poor psychosocial functioning and cognitive performance. LIMITATIONS: Cross-sectional data which limits our ability to infer directionality of our findings. CONCLUSION: These results suggest the presence of two subgroups regarding EP performance with unique clinical and neurodevelopmental profiles associated. Next steps will include using these data to identify a homogeneous group of patients to target these disabling symptoms with treatment.

Selective aging of the human cerebral cortex observed in vivo: differential vulnerability of the prefrontal gray matter.

In a prospective cross-sectional study, we used computerized volumetry of magnetic resonance images to examine the patterns of brain aging in 148 healthy volunteers. The most substantial age-related decline was found in the volume of the prefrontal gray matter. Smaller age-related differences were observed in the volume of the fusiform, inferior temporal and superior parietal cortices. The effects of age on the hippocampal formation, the postcentral gyrus, prefrontal white matter and superior parietal white matter were even weaker. No significant age-related differences were observed in the parahippocampal and anterior cingulate gyri, inferior parietal lobule, pericalcarine gray matter, the precentral gray and white matter, postcentral white matter and inferior parietal white matter. The volume of the total brain volume and the hippocampal formation was larger in men than in women even after adjustment for height. Inferior temporal cortex showed steeper aging trend in men. Small but consistent rightward asymmetry was found in the whole cerebral hemispheres, superior parietal, fusiform and orbito-frontal cortices, postcentral and prefrontal white matter. The left side was larger than the right in the dorsolateral prefrontal, parahippocampal, inferior parietal and pericalcarine cortices, and in the parietal white matter. However, there were no significant differences in age trends between the hemispheres.

Selective neuroanatomic abnormalities in Down's syndrome and their cognitive correlates: evidence from MRI morphometry.

We examined the pattern of neuroanatomic abnormalities in adults with Down's syndrome (DS) and the cognitive correlates of these abnormalities. Specifically, we compared this pattern with what would be predicted by the hypotheses attributing DS pathology to either premature aging or Alzheimer's disease. We measured a number of brain regions on MRIs of 25 subjects: 13 persons with the DS phenotype and 12 age- and sex-matched healthy volunteers. Study participants had no history of cardiovascular disease, diabetes, thyroid dysfunction, or seizure disorder. After statistical adjustment for differences in body size, we found that, in comparison with controls, DS subjects had substantially smaller cerebral and cerebellar hemispheres, ventral pons, mammillary bodies, and hippocampal formations. In the cerebellar vermis of DS subjects, we observed smaller lobules VI to VIII without appreciable differences in other regions. In addition, we noted trends for shrinkage of the dorsolateral prefrontal cortex, anterior cingulate gyrus, inferior temporal and parietal cortices, parietal white matter, and pericalcarine cortex in DS subjects compared with normal controls. The parahippocampal gyrus was larger in DS subjects. We found no significant group differences in the volumes of the prefrontal white matter, the orbitofrontal cortex, the pre- and postcentral gyri, or the basal ganglia. We conclude that the pattern of selective cerebral damage in DS does not clearly fit the predictions of the premature aging or Alzheimer's disease hypotheses. To examine the relationship between brain abnormalities and cognitive deficits observed in DS, we correlated the size of brain regions that were significantly reduced in DS with performance on tests of intelligence and language. The correlation analysis suggested age-related decline in the DS subjects in general intelligence and basic linguistic skills. General intelligence and mastery of linguistic concepts correlated negatively with the volume of the parahippocampal gyrus. There was no relationship between total brain size and the cognitive variables.