Haptic devices have been studied as useful tools for motor learning. In use of the devices, proprioceptors are used for movement perception. Therefore, it is important for designing the devices to characterize proprioceptor performance. This study focuses on the scheme to perceive velocity differences from beforeacceleration velocity for various accelerations. We measured the velocity JNDs (Just Noticeable Differences) in one-way elbow flexion movements to examine the following two hypotheses. (1) "Local scheme"; the magnitude of the present acceleration, which can be regarded as a local velocity difference, plays a crucial role. (2) "Global scheme"; the global velocity difference, which is defined as the difference between the present accelerating-velocity and the before-acceleration velocity, does so. For each of the schemes, the following characteristics are expected. (1) If acceleration magnitude affects the perception, humans cannot notice the velocity differences in acceleration conditions less than a threshold. It results in a tendency that velocity JNDs in small acceleration conditions would be much larger than those in large acceleration conditions. (2) If acceleration does not, but if the global velocity does, the velocity JNDs stay unchanged even though acceleration varies because humans perceive the velocity differences, just referring two different absolute velocities.