Ease of Tapping the Fingers in a Sequence Depends on the Mental Encoding.
Amy Geoffroy, Donald A. Norman · 1982
Abstract : We examined the difficulty of tapping different sequences of five finger taps, one tap per finger, with only the order varying for different sequences. Different sequences have different levels of difficulty, depending upon their structure. The same sequence can be easy or difficult to perform, depending upon how it is encoded. (Author)