TY - CONF
T1 - Investigating the size weight illusion in upper limb amputees
AU - Day, Sarah
AU - Buckingham, Gavin
N1 - Proceedings ISBN: 9781551311760
PY - 2014/8/22
Y1 - 2014/8/22
N2 - Introduction:The size weight illusion occurs when a person underestimates the weight of a larger object in relation to asmaller object of the same mass. This is well documentedin normal populations but there has only been one studylooking into its presence in populations with limb loss. Thisproject aims to expand on the work by Wallace comparingthe performance of a larger sample of upper limb amputeeswith able-bodied persons to investigate whether the sizeweight illusion exists in amputees and whether it is of thesame magnitude as in the normal population. There are several potential benefits to this study. Currently what causes the size weight illusion is unknown although there are several theories. Testing with active prosthetic users allow the researchers to eliminate certain variables such as sensory feedback as current prostheses used do not provide sensory feedback from the fingers to the user. The findingsfrom this study also provide a greater understanding of whatinformation individuals with a prosthetic limb use to judgethe weight of objects, which may have consequences for theenvironmental ergonomics of this population.Methodology:During our investigation we compared a group of upperlimb amputees using prosthetic devices to a group of peoplewith normal upper limb function. Approval for the study wasgranted by the University of Strathclyde Ethical Committee.Participants were tested one at a time in separate testingsessions. Participants were asked to lift objects of varying size and weight and ask them to rate them as a number, witha larger number indicating a larger weight. This number wasthen used to determine if the participants were experiencingthe size weight illusion. The order in which the objects wereoffered to the participants was random and different for eachparticipant. The data was analysed using T-tests and ANOVA with the SPSS software package.Results:The data collection phase is due to be completed on 31/3/14. To date we have collected data on 5 amputee and 5 control subjects.Conclusion:Preliminary analysis of the data shows that the amputeegroup did experience the size weight illusion. This supportsthe previous findings by Wallace. Interestingly, the magnitudeof the illusion and sensitivity to weight appear to be differentaccording to the subject groups, although this will be confirmed upon completion of the data collection
AB - Introduction:The size weight illusion occurs when a person underestimates the weight of a larger object in relation to asmaller object of the same mass. This is well documentedin normal populations but there has only been one studylooking into its presence in populations with limb loss. Thisproject aims to expand on the work by Wallace comparingthe performance of a larger sample of upper limb amputeeswith able-bodied persons to investigate whether the sizeweight illusion exists in amputees and whether it is of thesame magnitude as in the normal population. There are several potential benefits to this study. Currently what causes the size weight illusion is unknown although there are several theories. Testing with active prosthetic users allow the researchers to eliminate certain variables such as sensory feedback as current prostheses used do not provide sensory feedback from the fingers to the user. The findingsfrom this study also provide a greater understanding of whatinformation individuals with a prosthetic limb use to judgethe weight of objects, which may have consequences for theenvironmental ergonomics of this population.Methodology:During our investigation we compared a group of upperlimb amputees using prosthetic devices to a group of peoplewith normal upper limb function. Approval for the study wasgranted by the University of Strathclyde Ethical Committee.Participants were tested one at a time in separate testingsessions. Participants were asked to lift objects of varying size and weight and ask them to rate them as a number, witha larger number indicating a larger weight. This number wasthen used to determine if the participants were experiencingthe size weight illusion. The order in which the objects wereoffered to the participants was random and different for eachparticipant. The data was analysed using T-tests and ANOVA with the SPSS software package.Results:The data collection phase is due to be completed on 31/3/14. To date we have collected data on 5 amputee and 5 control subjects.Conclusion:Preliminary analysis of the data shows that the amputeegroup did experience the size weight illusion. This supportsthe previous findings by Wallace. Interestingly, the magnitudeof the illusion and sensitivity to weight appear to be differentaccording to the subject groups, although this will be confirmed upon completion of the data collection
KW - size weight illusion
KW - upper limb amputees
KW - prosthetic devices
UR - http://www.unb.ca/conferences/mec/
UR - http://www.unb.ca/conferences/mec/_resources/docs/mec14_proceedings.pdf
M3 - Abstract
SP - 63
T2 - MEC 14: Myoelectric Controls Symposium
Y2 - 19 August 2014 through 22 August 2014
ER -