Active brain-computer interfaces (BCI) are a novel communication/interaction pathway that relies on the performance of imagery tasks, that is, it provides control over computer applications directly from brain activity. The patterns of brain activity associated with these tasks are detected and decoded by the computer as commands for operating an external device. This study focuses on the possibility and practicality of expanding such systems by investigating the mental task of singing imagery. Singing imagery is the simple act of imagining singing a song in your head. Despite its straightforward nature, the potential of singing imagery as an alternative task for active BCIs or for increasing their number of commands has yet to be thoroughly investigated.
The research described in this study occurred in two phases. In the first study, singing imagery is combined with the commonly used imagery tasks in BCI research (the 5 commands most consistently used are: imagined movement of the left hand, right hand, feet, and tongue, as well as a “rest" state). Singing imagery was incorporated amongst these more common tasks and results analyzed, resulting in comparable classification/accuracy to conventional motor imagery tasks. Hence, based on the survey results, singing imagery could be considered as a potentially intuitive alternative mental task. Furthermore, singing imagery may also be a practical approach for increasing the number of commands to six, with accuracies as high as 60.7% achieved.
The second study investigated the potential of using “dual imagery" tasks (i.e., the simultaneous performance of two single tasks, in this case, singing imagery and one of the conventional motor imagery tasks) as additional BCI control tasks. Here, the analyses of the dual tasks and their constituent single tasks (alongside a “rest" state for some) were carried out to verify the possibility of differentiating them. Average accuracies as high as 64.1% and 63% were achieved these scenarios. Next, the dual imagery tasks were combined with conventional single motor imagery tasks to investigate increasing the number of commands to seven or eight. As a result, for the 7- and 8-class scenarios, accuracies as high as 55.4%, and 50.5%, which are well above the corresponding chance levels. Increasing the number of commands a BCI can recognize could significantly impact the user's experience with the device, and help the user avoid a high mental workload, possibly adding to quality of life. Based on the results of this research, singing imagery appears to be a potentially viable solution for improving active BCIs.
Read More: https://research.library.mun.ca/15971/