caa a22 4500 445351756 CHVBK 20180317142846.0 cr unu---uuuuu 170323e20110501xx s 000 0 eng 10.1007/s00221-011-2655-6 doi (NATIONALLICENCE)springer-10.1007/s00221-011-2655-6 Continuous visual field motion impacts the postural responses of older and younger women during and after support surface tilt [Elektronische Daten] [Jill Slaboda, Richard Lauer, Emily Keshner] The effect of continuous visual flow on the ability to regain and maintain postural orientation was examined. Fourteen young (20-39years old) and 14 older women (60-79years old) stood quietly during 3° (30°/s) dorsiflexion tilt of the support surface combined with 30° and 45°/s upward or downward pitch rotations of the visual field. The support surface was held tilted for 30s and then returned to neutral over a 30-s period while the visual field continued to rotate. Segmental displacement and bilateral tibialis anterior and gastrocnemius muscle EMG responses were recorded. Continuous wavelet transforms were calculated for each muscle EMG response. An instantaneous mean frequency curve (IMNF) of muscle activity, center of mass (COM), center of pressure (COP), and angular excursion at the hip and ankle were used in a functional principal component analysis (fPCA). Functional component weights were calculated and compared with mixed model repeated measures ANOVAs. The fPCA revealed greatest mathematical differences in COM and COP responses between groups or conditions during the period that the platform transitioned from the sustained tilt to a return to neutral position. Muscle EMG responses differed most in the period following support surface tilt indicating that muscle activity increased to support stabilization against the visual flow. Older women exhibited significantly larger COM and COP responses in the direction of visual field motion and less muscle modulation when the platform returned to neutral than younger women. Results on a Rod and Frame test indicated that older women were significantly more visually dependent than the younger women. We concluded that a stiffer body combined with heightened visual sensitivity in older women critically interferes with their ability to counteract posturally destabilizing environments. Springer-Verlag, 2011 Posture nationallicence Aging nationallicence Wavelet transform nationallicence Visual sensitivity nationallicence Functional principal component analysis nationallicence Slaboda Jill Department of Physical Therapy, College of Health Professions and Social Work, Temple University, 19140, Philadelphia, PA, USA aut Lauer Richard Department of Physical Therapy, College of Health Professions and Social Work, Temple University, 19140, Philadelphia, PA, USA aut Keshner Emily Department of Physical Therapy, College of Health Professions and Social Work, Temple University, 19140, Philadelphia, PA, USA aut Experimental Brain Research Springer-Verlag 211/1(2011-05-01), 87-96 0014-4819 211:1<87 2011 211 221 https://doi.org/10.1007/s00221-011-2655-6 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00221-011-2655-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Slaboda Jill Department of Physical Therapy, College of Health Professions and Social Work, Temple University, 19140, Philadelphia, PA, USA aut NATIONALLICENCE 700 1- Lauer Richard Department of Physical Therapy, College of Health Professions and Social Work, Temple University, 19140, Philadelphia, PA, USA aut NATIONALLICENCE 700 1- Keshner Emily Department of Physical Therapy, College of Health Professions and Social Work, Temple University, 19140, Philadelphia, PA, USA aut NATIONALLICENCE 773 0- Experimental Brain Research Springer-Verlag 211/1(2011-05-01), 87-96 0014-4819 211:1<87 2011 211 221 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer