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Claire Young

Publications and source records attributed to Claire Young.

4 recordsLinked to original sources
PubMed2004

The effects of ageing on stereopsis. A VEP study.

Differences in brain activation between young (n = 11, ages 21-35) and elderly (n = 8, ages 70-84) healthy participants were studied using visual evoked potentials (VEPs) to different kinds of computer generated random-dot patterns. The main stimulus of interest was a 2 x 2 array of rectangles whose rectangles moved to and fro in depth. Control conditions were similar 2 x 2 arrays, one with side-to-side lateral motion (LM) of the rectangles, and one a stationary baseline condition. The third non-stereo stimulus was an expanding field of small dots in radial motion (RM). Significant stereo related activation was found in both age groups. The stereo VEPs showed a longer latency of depth reversal triggered VEP peaks compared to control LM VEPs. The amplitudes of LM VEPs were larger than the baseline VEPs. Age-related differences were found not only in stereo but also in the other conditions. Thus the latency of early VEP peaks was shorter and their amplitude higher in the elderly for LM and baseline conditions, and the younger participants showed significantly higher activation in the later VEP peaks of all conditions. Our main finding is no evidence for age related stereo specific effects in brain activation, but instead more general and subtle changes that affect widely different visual stimulus conditions.

Adult↗
PubMed2004

Hallucinations in schizophrenia, sensory impairment, and brain disease: a unifying model.

Based on recent insight into the thalamocortical system and its role in perception and conscious experience, a unified pathophysiological framework for hallucinations in neurological and psychiatric conditions is proposed, which integrates previously unrelated neurobiological and psychological findings. Gamma-frequency rhythms of discharge activity from thalamic and cortical neurons are facilitated by cholinergic arousal and resonate in networks of thalamocortical circuits, thereby transiently forming assemblies of coherent gamma oscillations under constraints of afferent sensory input and prefrontal attentional mechanisms. If perception is based on synchronisation of intrinsic gamma activity in the thalamocortical system, then sensory input to specific thalamic nuclei may merely play a constraining role. Hallucinations can be regarded as underconstrained perceptions that arise when the impact of sensory input on activation of thalamocortical circuits and synchronisation of thalamocortical gamma activity is reduced. In conditions that are accompanied by hallucinations, factors such as cortical hyperexcitability, cortical attentional mechanisms, hyperarousal, increased noise in specific thalamic nuclei, and random sensory input to specific thalamic nuclei may, to a varying degree, contribute to underconstrained activation of thalamocortical circuits. The reticular thalamic nucleus plays an important role in suppressing random activity of relay cells in specific thalamic nuclei, and its dysfunction may be implicated in the biological vulnerability to hallucinations in schizophrenia. Combined with general activation during cholinergic arousal, this leads to excessive disinhibition in specific thalamic nuclei, which may allow cortical attentional mechanisms to recruit thalamic relay cells into resonant assemblies of gamma oscillations, regardless of their actual sensory input, thereby producing an underconstrained perceptual experience.

Arousal↗
PubMed2004

Transforming nursing practice: clinical systems and the nursing unit of the future.

The healthcare industry has historically focused information system expenditures on financial systems. Finally, enabling the practice of clinicians through information systems is beginning to be viewed as a strategic initiative for hospitals and health systems. Vendor applications are now better able to support clinician workflow. Infrastructure is better able to support mobile devices, which bring information to the bedside. Implementation of nursing applications provides a unique opportunity to redesign inefficient and redundant documentation, thereby enabling greater efficiency. Healthcare organizations can jump-start nursing automation by setting a finite and clear tactical plan for initiatives to be rolled out within a year in a single location. The single location enables the organization to experience how well the initiatives integrate to support optimal delivery of care. This article explores nursing information technology initiatives planned to be deployed at a 1,000-bed teaching facility through the use of a Nursing Unit of the Future.

Hospitals, Teaching↗