The effect of two types of virtual reality on voluntary center of pressure displacement.

Voluntary movements result in internal perturbations of balance and equilibrium. One variable regulated during movement is the position of the center of pressure (COP). Sensory information from the visual, vestibular and somatosensory systems is used in establishing relevant frames of reference for postural control.

Hypothalamic-opticochiasmatic gliomas mimicking craniopharyngiomas.

The differential diagnosis of suprasellar masses in the pediatric age group includes craniopharyngiomas and hypothalamic-opticochiasmatic gliomas (HOCGs). These tumors frequently display unique features on computed tomography and magnetic resonance imaging. We review two cases of pediatric suprasellar HOCGs with preoperative imaging characteristics resembling those of craniopharyngioma.

Primitive neuroectodermal tumor arising in long-standing cerebellar atrophy.

Primitive neuroectodermal tumors (PNETs) account for one fifth of childhood brain tumors. Although little is known of the pathobiology of this tumor type, there are associations with both genetic syndromes and exposures to specific environmental agents. Progressive cerebellar atrophy predating the presentation of a primary brain tumor, in the absence of a genetic syndrome, has not been reported with PNETs.

Enhanced myogenic tone in cerebral arteries from a rabbit model of subarachnoid hemorrhage.

Cerebral artery vasospasm is a major cause of death and disability in patients experiencing subarachnoid hemorrhage (SAH). Currently, little is known regarding the impact of SAH on small diameter (100-200 microm) cerebral arteries, which play an important role in the autoregulation of cerebral blood flow. With the use of a rabbit SAH model and in vitro video microscopy, cerebral artery diameter was measured in response to elevations in intravascular pressure.

An autosomal genomic screen for autism. Collaborative linkage study of autism.

Autism is a severe neurodevelopmental disorder defined by social and communication deficits and ritualistic-repetitive behaviors that are detectable in early childhood. The etiology of idiopathic autism is strongly genetic, and oligogenic transmission is likely. The first stage of a two-stage genomic screen for autism was carried out by the Collaborative Linkage Study of Autism on individuals affected with autism from 75 families ascertained through an affected sib-pair.

Finding specific genes that cause autism: a combination of approaches will be needed to maximize power.

Although autism is clearly inherited, it may be challenging to find the genes involved: The mechanism of inheritance is unknown, families with an autistic child are usually small, parent-child pairs are rare, and a fairly large number of genes may be involved, some or all of which may have a small effect on the phenotype. We discuss several strategies for finding genes, all of which may be used in combination to find the relevant genes.

The Pittsburgh study of normal sleep in young adults: focus on the relationship between waking and sleeping EEG spectral patterns.

The effects of age and gender on spectral characteristics of the waking EEG were investigated in a large sample of young adult men and women. In addition, relationships between spectral characteristics of the waking and sleeping EEG within an individual were explored. The sample included 28 females and 33 males in two age groups: 20-29 years (n = 32), and 30-40 years (n = 29).