Structural brain correlates of IQ changes in bipolar disorder

Background. There is increasing evidence that cognitive deficits are present in bipolar disorder (BP), but their neural correlates have not been fully explored. The aim of this study is to correlate structural brain abnormalities with cognitive performance in BP and to explore differences between clinical subtypes. Method. Thirty-six BP patients (13 men, 23 women) with a mean age of 39 years (range 21–63 years) underwent neuropsychological testing and imaging. Twenty-five patients had bipolar disorder I (BP I) and 11 had bipolar disorder II (BP II). Patients with co-morbid psychiatric diagnosis, drug and alcohol abuse or systemic illness were excluded. Correlations between cognitive perform…

Changing associations between cognitive impairment and imaging in multiple sclerosis as the disease progresses.

The authors explored cross-sectional associations between MRI parameters (lesion metrics, brain volumes, magnetization transfer ratio histograms, and metabolite concentrations) and cognition in 61 patients who experienced clinically-isolated syndromes (CIS) 7 years earlier. IQ decline and poorer overall cognition were associated with T2 white-matter lesions, and slow information-processing with both T2 lesions and gray-matter atrophy. In a previous study of the same cohort, gray-matter atrophy measured shortly after CIS failed to predict development of cognitive impairment years later. Our findings suggest that gray-matter pathology, reflected by atrophy measurements, becomes increasingly i…

Bipolar I and Bipolar II Disorder: Cognition and Emotion Processing

Background. Cognitive impairment may be part of the endophenotype of bipolar disorder (BP), but little is known about patterns and severity of impairment in BP subgroups and their relation to depression. The same applies to deficits in emotion processing known to be present in BP.Method. To explore the relationship between depression and impairment in cognition and emotion processing and the differences between BP subgroups, we assessed 36 (25 BP I and 11 BP II) patients using a cognitive battery and a facial emotion recognition task.Results. BP patients were impaired compared to published norms on memory, naming and executive measures (Binomial Single Proportion tests, p<0·05). Cognitiv…

Grey matter damage and overall cognitive impairment in primary progressive multiple sclerosis

Objectives: To identify associations between cognitive impairment and imaging measures in a cross-sectional study of patients with primary progressive multiple sclerosis (PPMS). Methods: Neuropsychological tests were administered to 27 patients with PPMS and 31 controls. Patients underwent brain conventional magnetic resonance imaging (MRI) sequences, volumetric scans and magnetization transfer (MT) imaging; MT ratio (MTR) parameters, grey matter (GM) and normal-appearing white matter (NAWM) volumes, and WM T2 lesion load (T2LL) were obtained. In patients, multiple linear regression models identified the imaging measure associated with the abnormal cognitive tests independently from the ot…

Characteristics of frontal and temporal cortex in relation to cognitive dysfunction in Bipolar Disorders

Cognitive impairment in relapsing-remitting multiple sclerosis can be predicted by imaging performed several years earlier.

Cognitive deficits in multiple sclerosis (MS) are common and correlate with contemporary MRI brain abnormalities, particularly atrophy, but the ability of imaging early in the disease to predict later cognitive impairment remains to be determined. Thirty relapsing—remitting MS patients recruited within three years of the onset of the disease, and in whom MRI had been performed at baseline and a year later, were assessed neuropsychologically five years later. Imaging parameters accounting for significant variance in cognitive performance were identified using multiple regressions, once confounding variables were controlled. Patients performed significantly worse than expected on tests of at…

Early imaging predicts later cognitive impairment in primary progressive multiple sclerosis

Background: Cognitive impairment in primary progressive multiple sclerosis (PPMS) is common and correlates modestly with contemporary lesion burden and brain volume. Using a cohort/case control methodology, we explore the ability of MRI abnormalities, including those in the normal-appearing brain tissue, to predict future cognitive dysfunction in PPMS. Methods: Thirty-one patients recruited into a longitudinal study within 5 years of onset of PPMS were assessed neuropsychologically on average 5.5 years later along with 31 matched healthy controls. MRI data obtained at entry into the study (lesion metrics, brain volumes, magnetization transfer ratio histogram metrics, and magnetic resonance …

IQ and the fronto-temporal cortex in bipolar disorder.

AbstractCognitive changes are documented in bipolar disorder (BP). Cortical volume loss, especially in prefrontal regions, has also been reported, but associations between cognition and cortical abnormalities have not been fully documented. This study explores associations between cognitive performance and cortical parameters (area, thickness and volume) of the fronto-temporal cortex in 36 BP patients (25 BPI and 11 BPII). T1-weighted volumetric MRI images were obtained using a 1.5 Tesla scanner. Cortical parameters were measured using surface-based morphometry and their associations with estimated premorbid, current IQ, visual memory, and executive function explored. Premorbid IQ was assoc…