Concordance between the Wada test and neuroimaging lateralization: Influence of imaging modality (fMRI and MEG) and patient experience.

The Wada test remains the traditional test for lateralizing language and memory function prior to epilepsy surgery. Functional imaging, particularly functional MRI (fMRI), has made progress in the language domain, but less so in the memory domain. Magnetoencephalography (MEG) has received less research attention, but shows promise, particularly for language lateralization. We recruited a consecutive sample of 19 patients with epilepsy who had completed presurgical work-up, including the Wada test, and compared fMRI (memory) and MEG (language and memory) with Wada test results. The main research question was the concordance between Wada and these two imaging techniques as preepilepsy surgery investigations. We were also interested in the acceptability of the three techniques to patients. Concordance rates (N=16) were nonsignificant (Cohen's Kappa) between fMRI and Wada test (memory) and between MEG and Wada test (memory and language). The Wada test was a well-established protocol used at several epilepsy surgery centers in the UK. Patients generally found the Wada test an odd, but not aversive procedure. Sixteen (84%) patients who were scanned reported some level of obtundation in MEG. We present these discordant findings in support of the position that functional imaging and the Wada test are distinctive procedures, with little in the way of overlapping mechanisms, and that patient's experience should be taken into account when procedures are selected and offered to them.

Monte Carlo configuration interaction with perturbation corrections for dissociation energies of first row diatomic molecules: C2, N2, O2, CO, and NO.

Dissociation energies for the diatomic molecules C2, N2, O2, CO, and NO are estimated using the Monte Carlo configuration interaction (MCCI) and augmented by a second order perturbation theory correction. The calculations are performed using the correlation consistent polarized valence "triple zeta" atomic orbital basis and resulting dissociation energies are compared to coupled cluster calculations including up to triple excitations (CCSDT) and Full Configuration Interaction Quantum Monte Carlo (FCIQMC) estimates. It is found that the MCCI method readily describes the correct behavior for dissociation for the diatomics even when capturing only a relatively small fraction (∼80%) of the correlation energy. At this level only a small number of configurations, typically O(10(3)) from a FCI space of dimension O(10(14)), are required to describe dissociation. Including the perturbation correction to the MCCI estimates, the difference in dissociation energies with respect to CCSDT ranges between 1.2 and 3.1 kcal/mol, and the difference when comparing to FCIQMC estimates narrows to between 0.5 and 1.9 kcal/mol. Discussions on MCCI's ability to recover static and dynamic correlations and on the form of correlations in the electronic configuration space are presented.

Self-management and well-being in adolescents with diabetes mellitus: do illness representations play a regulatory role?

This investigation examined the applicability of the self-regulatory model to adolescents with type 1 diabetes. Relationships among illness beliefs, diabetes self-management behaviors, psychological well-being, and blood glucose control were explored in 30 adolescents attending outpatient clinics in the United Kingdom. Correlation and regression analyses indicated that illness beliefs were not related to self-management behaviors, but both were important contributors to psychological well-being.

Primary sleep disorders can cause long-term sleep disturbance in patients with autoimmune mediated limbic encephalitis.

OBJECTIVES: Antibody mediated limbic encephalitis causes a sub acute encephalopathy with an amnestic syndrome, seizures and often an affective prodrome. Sleep disturbance including abnormal dream sleep and insomnia are described in a percentage of long-term survivors but there are very few detailed assessments of sleep disturbance in patients beyond the acute phase of illness. The objectives of this study were to understand the causes of sleep disturbance in the long-term survivors of antibody mediated limbic encephalitis. PATIENTS AND METHODS: We screened twelve patients under long-term follow up with sleep questionnaires and went on to perform detailed sleep studies (polysomnography) in those who reported sleep disturbance. RESULTS: Two were found to have persistent, severe central and obstructive sleep apnoea and two others to have restless legs and periodic limb movements of sleep. CONCLUSIONS: This highlights the need to investigate sleep disturbance in this group of patients. Effective treatments may be available to improve quality of life and daytime function.

Distinct critical cerebellar subregions for components of verbal working memory.

A role for the cerebellum in cognition has been proposed based on studies suggesting a profile of cognitive deficits due to cerebellar stroke. Such studies are limited in the determination of the detailed organisation of cerebellar subregions that are critical for different aspects of cognition. In this study we examined the correlation between cognitive performance and cerebellar integrity in a specific degeneration of the cerebellar cortex: Spinocerebellar Ataxia type 6 (SCA6). The results demonstrate a critical relationship between verbal working memory and grey matter density in superior (bilateral lobules VI and crus I of lobule VII) and inferior (bilateral lobules VIIIa and VIIIb, and right lobule IX) parts of the cerebellum. We demonstrate that distinct cerebellar regions subserve different components of the prevalent psychological model for verbal working memory based on a phonological loop. The work confirms the involvement of the cerebellum in verbal working memory and defines specific subsystems for this within the cerebellum.

The contribution of the cerebellum to cognition in Spinocerebellar Ataxia Type 6.

This study sought evidence for a specific cerebellar contribution to cognition by characterising the cognitive phenotype of Spinocerebellar Ataxia Type 6 (SCA-6); an autosomal dominant genetic disease which causes a highly specific late-onset cerebellar degeneration. A comprehensive neuropsychological assessment was administered to 27 patients with genetically confirmed SCA-6. General intellectual ability, memory and executive function were examined using internationally standardised tests (Wechsler Adult Intelligence Scale-III, Wechsler Memory Scale-III, Delis and Kaplan Executive Function System, Brixton Spatial Anticipation test). The patient group showed no evidence of intellectual or memory decline. However, tests of executive function involving skills of cognitive flexibility, inhibition of response and verbal reasoning and abstraction demonstrated significant impairment at the group level with large effect sizes. The results demonstrate an executive deficit due to SCA-6 that can be conceptualised as parallel to the motor difficulties suffered by these patients: the data support a role for the cerebellum in the regulation and coordination of cognitive, as well as motor processes that is relevant to individual performance.