Influence of continual biofeedback on jaw pursuit-tracking in healthy adults and in adults with apraxia plus aphasia.

Apraxia of speech (AOS) is a disorder of motor programming resulting from damage to premotor or anterior insula cortex. The authors used a pursuit visuomotor tracking task to test whether such a disorder interferes with development of motor programs or with modification of existing programs via integration of feedback. Healthy older adults (n = 15) and adults with AOS plus aphasia and nonverbal apraxia (n = 8) performed a jaw movement task with (a) continuous visual feedback of a target movement pattern and their jaw movement and (b) no feedback. Healthy speakers were more accurate and less variable with feedback, suggesting accurate development of a program and feedback integration. Apraxic individuals' performance accuracy and response to feedback suggested that the neurological damage impairs both development of new programs and efficient integration of feedback.

Age-related changes in motor control during articulator visuomotor tracking.

The present study provides normative data on changes in visuomotor control of the oral-facial system across the lifespan. Control of the lower lip, jaw, and larynx (i.e., fundamental frequency) was examined using a nonspeech visuomotor tracking (VMT) task, where subjects move the articulator of interest to track a moving target on an oscilloscope screen. This task examines articulator motor control during movements that are similar to speech but that do not impose linguistic units or the demands of coordinating multiple structures. Accuracy and within- and between-subject variability in tracking performance were measured by cross correlation, gain ratio, phase shift, and target-tracker amplitude difference. Cross-correlation analyses indicated that performance of children (aged 8;2 to 17;0 [years;months]) and older adults (aged 45;1 to 84;3) is poorer than that of younger adults (aged 17;1 to 45;0). Accuracy of movement amplitude tended to increase during development and decline with aging, whereas age did not appear to influence accuracy of temporal parameters in lip and jaw tracking. In contrast, age tended to influence individual variability in temporal but not amplitude parameters. Differences were noted between articulators. The data complement previous studies that considered accuracy and variability of articulator movement during speech. The VMT method and the data provided may be applied to assessment of impairments in the motor speech system and to differential diagnosis of motor speech versus linguistically based disorders.

Evaluating a superabsorbent hydropolymer dressing for exuding venous leg ulcers.

A new hydropolymer dressing was compared with an alginate dressing in a multicentre, prospective, controlled, randomised, stratified, open label trial of 113 patients with exuding venous leg ulcers. The study aimed to evaluate the performance of the dressings in terms of their ability to handle exudate, patient and user acceptability and cost-effectiveness. Patients were stratified according to volume of wound exudate (moderate/heavy) and randomised to the hydropolymer dressing or the alginate plus a secondary dressing. A statistically significant difference between treatment groups was observed in mean wear time, with a longer wear time observed in the hydropolymer group (3.91 days) compared with the alginate group (3.09 days, p = 0.001). In terms of patient and user acceptability, all 10 overall evaluations made by both patient and investigator were markedly in favour of the hydropolymer dressing (p < 0.001 to p = 0.020). The use of the hydropolymer dressing for patients with moderate to heavily exuding venous leg ulcers has statistically significant advantages over the alginate dressing in terms of wear time and investigator and patient acceptability. It is anticipated that this reduction in dressing frequency will translate into a cost-effective wound treatment.

The Tielle family of dressings: overview of the product range.

The Tielle family (Johnson & Johnson Medical) is a range of dressings that come in a variety of shapes and sizes, designed to fit the different types and locations of wounds that occur in practice. There are three types--Tielle, Tielle Lite and Tielle Plus--and the choice of dressing should be based on the degree of exudate that the wound is producing. This product focus aims to give an overview of the range and provides research-based evidence for application in clinical practice.

Comparison of the musculoskeletal structure of the orbits of the migrating and non-migrating eyes in the winter flounder (Pseudopleuronectes americanus).

The winter flounder, Pseudopleuronectes americanus, undergoes a metamorphosis that involves the migration of one eye across the top of the head to a position adjacent to the non-migrating eye on the right lateral side. The metamorphosis involves changes in the nervous and musculoskeletal components of the orbits. The major difference between the two eyes is that the orbit of the left eye is composed completely of bone, whereas that of the right is partially bounded by jaw muscles. The orbital bones of the left eye cause the path of the extraocular muscles and optic nerve to be deflected and twisted before insertion, causing the left lateral and medial rectus muscles to be significantly shorter than the same muscles of the right eye. These orbital asymmetries are necessary to accommodate the final position of the eyes in an extraorbital position on the right side, which is a specialized adaptation allowing the flounder to lead both a benthic and pelagic existence.