# The Effect of Isomorphic Pitch Layouts on the Transfer of Musical Learning +
## 1 Introduction  
Music instrument learning is a domain commonly associated with numerous social, emotional and cognitive benefits. These include increased self-esteem [1; 2], increased sense of social identity [3; 4], and the provision of a medium for self-expression [5]. Cognitive benefits include improved fluid intelligence [6] increased IQ [7], slowed cognitive decline [8] and increased executive functioning in older adults [9]. In an age where computers are so prevalent and technological advances are constant, it seems desirable for musical instruments also to advance so as to increase accessibility to the many benefits of music learning. Indeed, a number of new music interfaces, such as the Thummer [10], AXiS-49 [11], LinnStument [12], and Lightpad Block [13] have been developed over the last decade. So far, however, none of these have achieved widespread or \"mainstream\" acceptance. This may be due to a lack of clear and agreed upon guidelines as to what the important features of successful musical instruments(traditional or digital) are [14]. [PERSON] and colleagues [10] suggested that desirable features to control on musical instruments include pitch, dynamics, articulation, attack/release, and vibrato. \"Touchability\", that is, the ability to make a physical connection with an interface, is another desirable trait of musical interfaces, relating primarily to the user's ability to control the quality of an instrument's sound. However, before aspects of sound quality can be accurately manipulated, deciphering and memorising the placement of pitches is a crucial first step in learning how to play any given instrument (traditional or digital). [PERSON] and [PERSON] [15] argued that _learnability_ and _playability_ are important features of instrument design in terms of their influences on how fast a new motor control program is devised by the learner. Learnability, in this instance, refers to how easy it is to understand and acquire the skills required to play an instrument, that is, to understand and remember the patterns of musical pitches contained within a certain layout. Playability refers to how easy it is to execute the physical motions involved in playing an instrument. These two aspects are related to the first two of three stages of motor learning described by [PERSON] and [PERSON] [16]. In the _cognitive phase_, patterns are appraised and potential motor techniques are tested to determine which solution is optimal. In the _fixation stage_, the optimal motor solution identified in the previous phase is practised and eventually mastered. When the _autonomous stage_ is reached, less conscious attention is required for the performer to execute the motor skill. This study focuses on the cognitive phase of motor skill development--a phase that is, according to the above characterisation, foundational. Two features of pitch layouts that have been empirically tested so far for their effects on learnability and playability are _major second adjacency_ (whether pitches a major second apart are next to each other or not) and _shear_ (whether the pitch axis is vertical or slanted) [15]. The results showed that the accuracy of musicians' performances on a series of tasks was higher on layouts with adjacent major seconds than on layouts with non-adjacent major seconds. The results also hinted at an overall positive effect of a vertical pitch axis on accuracy (in an isomorphic layout, the pitch axis is the direction in which pitches ascend [17; 18]--see Figures 5 and 7 for examples). However, this latter effect was inconsistent across the different tasks within the study. Furthermore, only _isomorphic_ pitch layouts were assessed. An isomorphic pitch layout is one in which each given spatial relationship between two note-playing \"triggers\" (e.g., keys, buttons, or fretted strings) always produces the same musical interval. A non-isomorphic layout is one where a given spatial relationship between two pitch triggers can produce differing musical pitch intervals.