A proposed comparative study on fine hand posture to capture and quantify unimanual and bimanual dysfunctional behaviour in a virtual environment

M. Edwards

Cognitive Science, Department of Computer Science, University of Melbourne, Carlton, Australia

This paper proposes the need to scrutinize hand dysfunction, a subject that has a substantial body of knowledge. However, the departure lies in the inability to quantify o r apply metrics to hand impairment. The paper proposes to apply virtual world technology in order to diagnose, quantify, enhance and revitalize hand usage that has otherwise been restricted or impaired with subsequent impact on life or later life. Hand dysfunction here covers: impaired function through disease rendering the hand physically abnormal relative to typical behaviour, the inability to construct precision patterns as a consequence of cognitive and/or motor brain dysfunction manifesting as tremor, spastic, Tourette's syndrome, or through bad health, aging, accidental mishap and birth defect. A highly specialized example of the functional use of precision patterns is in clinical-surgical medical practice or engaged in instrument making. The focus is on conduct and completeness of precision prehension patterns that are central to any intricate, delicate, dexterous and precise activity performed in daily life.

The proposed study suggests a departure from a passive un-inclusive instance to one where 3-dimensional quantitative measurement and monitoring occurs through applying virtual world technology (VWT). On a contempoaray basis, that comprises of a top-end workstation, with peripheral hardware, such as glove input device(s) (e.g. Cyberglove™) and a head-mounted device (HMD), that are used to interact/be immersed in a software- g enerated, 3-dimensional virtual environment (VE). It is the property of immersion and context of interaction that will register and define the type of hand dysfunction in a VE. The proposed first stage of testing lends itself to general 3-dimensional spatial-temporal quantitative measurement that observes a prescribed sequence of scenarios addressing both unimanual and bimanual behaviour. The study observes ethical practice in that the subject should not approach or register pain under the sequence of events. Subject(s) with hand dysfunction(s), that is unimanual or bimanual should at least be able to wear a standard glove-input device, with the proviso of not severe physical abnormality. The subject(s) proceed through routine manipulatory scenarios; dynamic and static, that is hand gesture and hand posture. The quality of the hand pattern is captured spatial-temporally in 3 dimensions. The second part of the test may act as a comparative template against the subject(s) database of behaviour with specialized hand function of a surgeon to normal cases. The essences of the study is to be able to quantify, introduce metrics and to define the disparities between a normal able hand, relative to specialized hand function of a variety of factors to hand dysfunction. The article places significance on the fingers (extensors) extremities tips, pads and sides, yet not with the inclusion of nails. The study appraises and captures hand capability and provides for a forum in recuperative or corrective strategies and behaviour of hand use.

The areas where the findings would have an influence is in rehabilitative physiotherapy (provides a new lease of manipulative activity to hand impaired subjects), dexterous robotic manipulators, clinical-surgical medical practice and telepresence in and out of a virtual environment. Another dimension addresses an aging population susceptible to diminished hand activity, as well as introducing a possible technique as a diagnostic tool to monitor onset of dysfunction. The ramifications of the work are widespread.

Poster presented at Measuring Behavior 2000, 3rd International Conference on Methods and Techniques in Behavioral Research, 15-18 August 2000, Nijmegen, The Netherlands

© 2000 Noldus Information Technology b.v.