 This study proposes a brain-computer interface, BCI, based version of the symbol-digit modalities test, BCIS-DMT, which can be used to measure cognition in individuals with severe motor impairments. The BCIS-DMT uses steady-state visual evoked potentials, steps, to identify and decode the user's responses. The study found that the BCIS-DMT had high accuracy when compared to the standard SDMT, indicating that it may be useful for measuring cognitive function in individuals with severe motor impairments. This article was authored by Xiao Jiangchen, Nan Hu, and Xirong Gao.