Date of Award


Degree Type




First Advisor

Slifkin, Andrew

Subject Headings

Human mechanics, Motor ability, Motor imagery, Human motor control, Imagery


Research has shown similarities between actual movement durations (AMD) and imagined movement durations (IMD). These similarities are believed to reflect the extent to which an action is represented by an internal model or emulator in the brain. Differences in AMD and IMD could be due to the employment of online feedback processes during actual movement in addition to emulated feedback as suggested by emulation theory. The current study was framed by these basic components of emulation theory. Methodology similar to a study by Papaxanthis, Schieppati, Gentili, and Pozzo (2002) was used to examine AMD and IMD of the arm under different conditions of added load and practice with the hypothesis that AMD and IMD would diverge with practice. The current study replicated the previous findings of a nonsignificant difference between AMD and IMD. As opposed to divergence, the results reveal an independent decrease in AMD and lack of change in IMD over 10 blocks of trials. The results suggest that the lack of change in IMD reflects a process that protects previous learning from catastrophic interference (McCloskey and Cohen, 1989). Other analyses revealed that the variability of IMD was larger than that of AMD but also revealed that the variability of both decreased with practice. It is suggested that both practice and feedback play a role in improving the consistency of a movement's timing. Significant correlations between AMD and IMD were also found. The results are consistent with the basic components of the emulation model

Included in

Psychology Commons