Shoulder Kinematics and Spatial Pattern of Trapezius Electromyographic Activity in Real and Virtual Environments

The main objective was to quantify the effects of five different slopes on trunk and shoulder kinematics as well as shoulder kinetic and muscular demands during manual wheelchair (MWC) propulsion on a motorized treadmill. Eighteen participants with spinal cord injury propelled their MWC at a self-selected constant speed on a motorized treadmill set at different slopes (0°, 2.7°, 3.6°, 4.8°, and 7.1°). Trunk and upper limb movements were recorded with a motion analysis system. Net shoulder joint moments were computed with the forces applied to the handrims measured with an instrumented wheel. To quantify muscular demand, the electromyographic activity (EMG) of the pectoralis major (clavicular and sternal portions) and deltoid (anterior and posterior fibers) was recorded during the experimental tasks and normalized against maximum EMG values obtained during static contractions. Overall, forward trunk flexion and shoulder flexion increased as the slope became steeper, whereas shoulder flexion, adduction, and internal rotation moments along with the muscular demand also increased as the slope became steeper. The results confirm that forward trunk flexion and shoulder flexion movement amplitudes, along with shoulder mechanical and muscular demands, generally increase when the slope of the treadmill increases despite some similarities between the 2.7° to 3.6° and 3.6° to 4.8° slope increments.

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The sense of presence in virtual environments:

Zeitschrift für Medienpsychologie ◽

10.1026//1617-6383.15.2.69 ◽

2003 ◽

Vol 15 (2) ◽

pp. 69-71 ◽

Cited By ~ 84

Author(s):

Thomas W. Schubert

Keyword(s):

Virtual Environments ◽

Coding Theory ◽

Model Building ◽

Self Report ◽

Survey Study ◽

Spatial Presence ◽

Component Structure ◽

Sense Of Presence ◽

Being There ◽

Measure Sense

Abstract. The sense of presence is the feeling of being there in a virtual environment. A three-component self report scale to measure sense of presence is described, the components being sense of spatial presence, involvement, and realness. This three-component structure was developed in a survey study with players of 3D games (N = 246) and replicated in a second survey study (N = 296); studies using the scale for measuring the effects of interaction on presence provide evidence for validity. The findings are explained by the Potential Action Coding Theory of presence, which assumes that presence develops from mental model building and suppression of the real environment.

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Dreamlike and Playful Virtual Environments to Inspire Children’s Divergent Thinking

Journal of Media Psychology Theories Methods and Applications ◽

10.1027/1864-1105/a000279 ◽

2020 ◽

pp. 1-11

Author(s):

Jérôme Guegan ◽

Claire Brechet ◽

Julien Nelson

Keyword(s):

Virtual Environments ◽

Divergent Thinking ◽

Idea Generation ◽

Combined Processes ◽

Office Environment ◽

School Aged Children

Abstract. Computers have long been seen as possible tools to foster creativity in children. In this respect, virtual environments present an interesting potential to support idea generation but also to steer it in relevant directions. A total of 96 school-aged children completed a standard divergent thinking task while being exposed to one of three virtual environments: a replica of the headmistress’s office, a replica of their schoolyard, and a dreamlike environment. Results showed that participants produced more original ideas in the dreamlike and playful environments than in the headmistress’s office environment. Additionally, the contents of the environment influenced the selective exploration of idea categories. We discuss these results in terms of two combined processes: explicit references to sources of inspiration in the environment, and the implicit priming of specific idea categories.

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