| Popis: |
Brain Computer Interfaces (BCIs) are the systems that provide a directcommunication channel between human brain and environment. P300 potentials areinvoluntary brain responses which are used to control BCI systems. In order toelicit P300 responses, stimulus presentation must be provided to the users.However, there are not common paradigmsor optimal parameters for all BCI users, or all BCI applications. Using themost convenient method and parameters for each user individually will improvesystem performance. This study proposes a visual stimulus module for P300 based BCIs. Themodule offers to design stimulus interfaces based on three different stimulusinterfaces, including row/column, single character and region based paradigms.The module also provides customization of the stimulus interface by settingoptimal parameters for individuals practically. Furthermore, in this study, wealso explained synchronization between stimulus interface and data acquisitionmodule in detailed. In order to test the stimulus module, stimulus interfacesbased on three visual stimulus paradigms were designed. All the paradigms weretested by three subjects. P300 responses yielded with three paradigms werecompared by using one-way statistical analysis of variance (ANOVA) method.Preliminary results revealed that average amplitude and latency of P300potentials that were elicited by the different paradigms may differ. |
