Medicine and Health Sciences Commons^™

Erroneous Measurement Of Intracranial Pressure Caused By Simultaneous Ventricular Drainage: A Hydrodynamic Model Study, H. Wilkinson, Jorge Yarzebski, E. Wilkinson, Frederick Anderson

Jorge L. Yarzebski

Intracranial pressure (ICP) is often measured from intraventricular catheters, a technique that allows therapeutic drainage of ventricular cerebrospinal fluid (CSF) as an aid in controlling ICP and circumventing obstruction. Drainage of CSF simultaneously with ongoing ICP measurement has been advocated as safe and efficient, and devices are commercially available to permit this practice; however, this concept has been seriously challenged, based on clinical observations. The inaccuracy induced by simultaneous CSF drainage and ICP monitoring is quantitated in this report in a mechanical brain model using a standard ventricular catheter. The following conclusions have been confirmed: 1) rapid CSF drainage induces …

T2 And T3 Sympathetic Ganglia In The Adult Human: A Cadaver And Clinical-Radiographic Study And Its Clinical Application, Jorge Yarzebski, H. Wilkinson

Jorge L. Yarzebski

The technique of percutaneous radiofrequency (RF) upper thoracic sympathectomy mandates an exact knowledge of the anatomical location of the sympathetic ganglia. Because conflicting descriptions are given in anatomy texts, we examined the T2 and T3 sympathetic ganglia in 48 sympathetic chains in adult cadavers to measure the exact location of the ganglia. Measurements were made relative to their distances (a) dorsal to the ventral surface of the vertebral body and (b) rostral or caudal to the midpoint of the vertebral body. Median locations of T2 and T3 ganglia were 17 to 20 mm dorsal to the ventral surface of the …

Predictive Validity Of The Updrs Postural Stability Score And The Functional Reach Test, When Compared With Ecologically Valid Reaching Tasks, M. Jenkins, Andrew Johnson, J. Holmes, F. Stephenson, S. Spaulding

Andrew M. Johnson

Balance problems and falls are a common concern among individuals with Parkinson's disease (PD). Falls frequently occur during daily activities such as reaching into cupboards in the kitchen or bathroom. This study compared the correlation among two standard postural stability tests - the postural stability score on the Unified Parkinson's Disease Rating Scale (UPDRS) and the Functional Reach Test (FRT) - and ecologically valid reaching tasks that correspond to reaching at different cupboard heights among 20 individuals with PD and 20 age-matched controls. Both the FRT and the UPDRS postural stability tests are quick measures that can be performed during …

Dual-Task Interference: The Effects Of Verbal Cognitive Tasks On Upright Postural Stability In Parkinson's Disease, J. Holmes, M. Jenkins, Andrew Johnson, S. Adams, S. Spaulding

Andrew M. Johnson

Although dual-task interference has previously been demonstrated to have a significant effect on postural control among individuals with Parkinson's disease, the impact of speech complexity on postural control has not been demonstrated using quantitative biomechanical measures. The postural stability of twelve participants with idiopathic Parkinson's disease and twelve healthy age-matched controls was evaluated under three conditions: (1) without a secondary task, (2) performing a rote repetition task and (3) generating a monologue. Results suggested a significant effect of cognitive load on biomechanical parameters of postural stability. Although both groups increased their postural excursion, individuals with Parkinson's disease demonstrated significantly reduced …

An Exploration Of The Burden Experienced By Spousal Caregivers Of Individuals With Parkinson's Disease, Kaitlyn Roland, Mary Jenkins, Andrew Johnson

Andrew M. Johnson

Although previous research has attempted to identify the needs of caregivers for individuals with Parkinson's disease (PD), most has focused on the demands associated with the physical needs of the patient, and not on "mental burden." This study used the repertory grid method to capture the full range of caregivers' subjective experience, quantify their perceptions, and to acquire information that might be useful in directing remediation attempts. Within this sample, caregivers reported far greater burden from "mental stress" (e.g., worrying about individual's safety) than from "physical stress" (e.g., lifting individual into bed). Specifically, caregivers were primarily concerned about spousal safety, …

Lifting Without Seeing: The Role Of Vision In Perceiving And Acting Upon The Size‐Weight Illusion, Gavin Buckingham, Melvyn Goodale

Gavin Buckingham

Our expectations of an object’s heaviness not only drive our fingertip forces, but also our perception of heaviness. This effect is highlighted by the classic size-weight illusion (SWI), where different‐sized objects of identical mass feel different weights (Charpentier, 1891) long after any initial errors in the application of fingertip forces have been corrected (Flanagan & Beltzner, 2000).

Here, we examined whether our expectations about the weight of an upcoming lift are sufficient to induce the SWI in a single wooden cube when lifted without visual feedback, by varying the size of the object seen prior to the lift during a …

Laterality, Perception, And Action During The Size-Weight Illusion, Gavin Buckingham, Nathalie Ranger, Melvyn Goodale

Gavin Buckingham

In the classic size-weight illusion (SWI), a small object will feel heavier than an larger object of equal weight (Charpentier, 1891). Individuals continue to perceive this illusory difference in weight long after their gripping and lifting forces have scaled to the actual, identical, mass of the illusion-inducing stimuli (Flanagan & Beltzner, 2000).

The independence of our weight perception and fingertip force application has only been quantified in the right hand of right-handers. The immunity to this perceptual illusion may be affected by manual asymmetries (e.g., Gonzalez, Ganel & Goodale, 2006).

We examined perception of heaviness and fingertip force scaling in …