That sounds like the Integrated Visual and Auditory Continuous Performance Test, except it was 1s and 2s for DD.

It put her to sleep. She dozed off.

Her scores on it (0.04 percentile to 75th percentile) were largely discounted in light of the observations that the neuropsych made during the exam as well as the results of parts of the NEPSY and the various rating scales.

DD and I both thought that the test ought to be banned by the Geneva Convention. It was torture.