A double blind randomized study was done in Australia about Brahmi. The NIH has the results.

" The results show a significant effect of the Brahmi on a test for the retention of new information. Follow-up tests showed that the rate of learning was unaffected, suggesting that Brahmi decreases the rate of forgetting of newly acquired information. Tasks assessing attention, verbal and visual short-term memory and the retrieval of pre-experimental knowledge were unaffected. Questionnaire measures of everyday memory function and anxiety levels were also unaffected."

What this basically says is that if the subject can learn the new information, the later forgetting of this information is lessened by the use of Brahmi.

It sounds like its value is on long term memory functions but not immediate or short term memory functions. Most with PCS struggle with short term and immediate memory functions.