Anticipatory and Compensatory Postural Adjustments of Lumbar Muscles in Sandbag-catching Test with Size-weight Illusion
Xie Lin
Feng Jinsheng
Wang Jian
Abstract：Objective To investigate the effects of erroneous task-related prediction on postural control strategies,the anticipatory and compensatory postural adjustments (APAs and CPAs) of the lumbar postural muscles were detected through the repeated sandbag-catching tests with the size-weight illusion.Methods Eighteen male subjects were asked to catch two sizes of falling sandbags with a tray held in their hands without knowing that the sandbags were of the same weight.The surface electromyograms (sEMGs) of the lumbar muscles were recorded synchronously,and the activated times and integrals of EMG activities(IEMGs) during the APA and CPA phases were calculated.Results At first,the lumbar muscles were activated earlier and performed stronger APAs when the sandbag was larger.However,after repeated catching,the lumbar muscle reactions rapidly showed no significant difference between the large and small sizes of sandbags,while the subjects' oral reports revealed the size-weight illusion.Conclusion Perceptual prediction based on visual information influences the APAs and CPAs of lumbar muscles in the novel sandbag-catching task.But when the task-related perceptual prediction is erroneous,CNS can rapidly adjust the strategies to orchestrate an optimal postural control based on the actual perturbation.
Keywords：anticipatory postural adjustmentscompensatory postural adjustmentssize-weight illusionsposture control
Publication Date：2019-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：6( 1-6 )