On the relation of PAG neurons to laryngeal and respiratory muscles during vocalization in the monkey

Despite evidence from previous unit recording, microstimulation, lesioning and anatomical studies, the functions of the midbrain periaqueductal gray (PAG) remain unclear. We attempted to clarify the function of the PAG by recording activity of PAG units along with laryngeal and respiratory electromyograms (EMG) during vocalization in awake monkeys. PAG units were classified with respect to vocalization on the basis of their discharge patterns as 'early burst', 'late burst', 'tonic-increase' and 'tonic-off', with the vast majority being of the early- and late-burst type. Early-burst cells were correlated most frequently with inspiratory muscles of the respiratory system and laryngeal abductor muscles. Late-burst cells were most clearly correlated with laryngeal adductor and expiratory respiratory muscles. Data from spike-triggered averaging and parametric correlations indicate that most cells are related to single muscles, but a significant number were related to functionally related groups of two or more muscles. The results suggest that the PAG determines qualitative aspects of vocalization by the multisynaptic action its cells have on laryngeal and respiratory motoneurons.     

Craniofacial development in children with unilateral clefts of the lip, alveolus, and palate treated according to four different regimes. II. Mandibular and vertical development.

Lateral skull radiographs of 85 patients with unilateral clefts of the lip, alveolus and palate treated according to four different regimes were compared longitudinally, at three different ages, regarding mandibular and vertical facial development. It was found that there were no lasting differences in mandibular morphology resulting from regimes including primary or early secondary bone grafting. The non grafted group, however, showed increased mandibular length and anterior height. The jaw angle was increased and there was a more favourable sagittal jaw relationship. Regimes that included primary bone grafting were associated with reduced upper anterior facial height, which resulted in less harmonious facial proportions compared with treatment regimes including early secondary bone grafting done during the mixed dentition, or no bone grafting at all. Vertical development was greatest where bone grafting was excluded.     

Objectively measuring physical ability in elderly persons: the Physical Capacity Evaluation.

The Physical Capacity Evaluation, a performance measure of functional capabilities comprised of 13 tasks simulating those used in activities of daily living, was tested on 289 community-dwelling elderly people and compared against a widely used self-report measure of function, the Health Assessment Questionnaire. Factor analysis identified one dominant component in each instrument. Internal consistency reliability (Cronbach's alpha) was .90 for both instruments. Global disability (Health Assessment Questionnaire) and function (Physical Capacity Evaluation) scores were correlated -.74. One-week retest reliabilities on 58 subjects were .94 for the Physical Capacity Evaluation and .95 for the Health Assessment Questionnaire. The Physical Capacity Evaluation is a valid and reliable measure of physical performance for use with elderly people.