Neural activation patterns during working memory tasks and OSA disease severity: preliminary findings.

Study Objectives: Obstructive sleep apnea (OSA) is associated with cognitive impairments in working memory (WM). Neuronal activation during WM tasks can be indirectly assessed by blood oxygen level-dependent functional magnetic resonance imaging (BOLD-fMRI). The purpose of this study was to describe BOLD-fMRI responses during 2 separate working memory tasks and a finger tapping task in men with OSA.

Reduced neural habituation in the amygdala and social impairments in autism spectrum disorders.

Objective: Amygdala dysfunction has been proposed as a critical component in social impairment in autism spectrum disorders. This study was designed to investigate whether abnormal habituation characterizes amygdala dysfunction in autism spectrum disorders and whether the rate of amygdala habituation is related to social impairment.

Method: Using functional MRI, the authors measured change over time in activation of the amygdala and fusiform gyrus to neutral facial stimuli in adults with autism spectrum disorders and healthy comparison adults.

Abnormal functional connectivity in autism spectrum disorders during face processing.

Abnormalities in the interactions between functionally linked brain regions have been suggested to be associated with the clinical impairments observed in autism spectrum disorders (ASD). We investigated functional connectivity within the limbic system during face identification; a primary component of social cognition, in 19 high-functioning adults with ASD and 21 age-and IQ-matched control adults. Activation during identification of previously viewed faces and houses using a one-back paradigm was compared.

A twin study of cognitive function in chronic fatigue syndrome: the effects of sudden illness onset.

Variable reports of neuropsychological deficits in individuals with chronic fatigue syndrome (CFS) may, in part, be attributable to methodological limitations. In this study, these limitations were addressed by controlling for genetic and environmental influences and by assessing the effects of comorbid depression and mode of illness onset. Specifically, the researchers conducted a co-twin control study of 22 pairs of monozygotic twins, in which 1 twin met strict criteria for CFS and the co-twin was healthy.

Increased amygdala activation to neutral faces is associated with better face memory performance.

Recent evidence suggests that the role of the amygdala may extend beyond threat detection to include processing socially relevant stimuli in general. Thus, we investigated perception and memory for neutral faces; a stimulus-type that lacks emotional valence yet contains relevant social information. Participants viewed neutral faces or houses when undergoing functional MRI.

Trail making test errors and executive function in schizophrenia and depression.

The Trail Making Test (TMT) frequently is used as a measure of executive cognitive function. However, traditional use of test completion time as the primary outcome score does not give the more detailed information on cognitive processes that analysis of test-taking errors may provide. The present study compared TMT performance of three groups: patients with schizophrenia, patients with major depression, and healthy control participants (n = 30 for each group).

Cerebral and cerebellar motor activation abnormalities in a subject with Joubert syndrome: functional magnetic resonance imaging (MRI) study.

Joubert syndrome is an autosomal recessive disorder characterized by hypotonia, ataxia, developmental delay, and a distinctive hindbrain malformation involving the cerebellum and brain stem, visualized radiographically on magnetic resonance imaging (MRI) as the "molar tooth sign." In postmortem brains from subjects with Joubert syndrome, there is an apparent absence of decussation of both corticospinal and superior cerebellar tracts, although the functional significance has not been elucidated. We sought to explore the cerebral and cerebellar activation pattern elicited by finger tapping in an adolescent with Joubert syndrome and in a normal control subject using functional MRI.

Cognitive processing in monozygotic twins discordant for chronic fatigue syndrome.

Twenty-one pairs of monozygotic twins discordant for chronic fatigue syndrome (CFS) and 21 matched healthy control (HC) subjects were assessed with 5 untimed tests and 5 timed tests from the computer-based NeuroCognitive Assessment Battery (R. K. Mahurin, 1993).

Age and features of movement influence motor overflow.

Objectives: To measure the magnitude and prevalence of motor overflow to the arm at rest during attempted unilateral arm movements.

Design: Cross-sectional assessment.

Setting: Motor physiology laboratory.

Single-photon emission computerized tomography and neurocognitive function in patients with chronic fatigue syndrome.

Objective: The purposes of this study were to compare functional imaging under control and experimental conditions among patients with chronic fatigue syndrome (CFS) and healthy persons and to examine perceived and objective performance on a test of attention and working memory previously found to be difficult for persons with CFS.

Methods: Single-photon emission computerized tomography scans were completed on 15 subjects with CFS and 15 healthy persons twice: at rest and when performing the Paced Auditory Serial Addition Test (PASAT).

Results: No group differences were found for performance on the PASAT despite CFS subjects' perceptions of exerting more mental effort to perform the task than healthy subjects.

The functional neuroanatomy of the placebo effect.

Objective: Administration of placebo can result in a clinical response indistinguishable from that seen with active antidepressant treatment. Functional brain correlates of this phenomenon have not been fully characterized.

Method: Changes in brain glucose metabolism were measured by using positron emission tomography in hospitalized men with unipolar depression who were administered placebo as part of an inpatient imaging study of fluoxetine.

Does cognitive function improve with quetiapine in comparison to haloperidol?

Recent evidence suggests that schizophrenia patients taking atypical antipsychotic medications may perform better on some tests of cognitive function than those treated with older antipsychotics. The current study compared the effects of quetiapine and haloperidol on measures of executive function, memory and attention. Subjects were 58 stable outpatients with schizophrenia (DSM III-R) who received a battery of cognitive tests as part of a randomized, double-blind, multi-site clinical efficacy study conducted by AstraZeneca Pharmaceuticals.