Variations in Anterior-Posterior CoP Patterns in Elderly Adults Between Psychophysically Detected and Non-Detected Short Horizontal Perturbations

Using an ultra-low-vibration sliding linear investigative platform for assessing lower limb stability (SLIP-FALLS), postural responses were evaluated while subjects stood on a platform that was given a short anterior perturbation presented in one of 2 sequential test intervals for a set of 30 trials. An adaptive 2-alternative-forced-choice protocol required the subject to detect platform movement. Anterior-posterior centers-of-pressure (AP CoP) were compared among the detected and non-detected trials for the healthy elderly adults (HEA) and diabetic peripheral neuropathy (DPN) elderly adults. Results indicate that there is a significant difference between the CoP patterns for a detected and non-detected trial. Also, the range of sway is found to be higher in the case of DPN elderly adults when compared to HEA. However, the AP CoP pattern for detected trials in both HEA and DPN were the same