The 4.8.4 version of brainworkshop for Mac was available to download on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The most popular version among the program users is 4.8. This free Mac application is an intellectual property of Radix. The software lies within Games, more precisely Puzzle. We recommend checking the downloaded files with any free antivirus.
From the developer:
Brain Workshop implements the memory task called dual n-back. The dual n-back task involves remembering a sequence of spoken letters and a sequence of positions of a square at the same time, and identifying when a letter or position matches the one that appeared n trials earlier. Brain Workshop can closely replicate the conditions of the original study.
You may want to check out more Mac applications, such as Web Sudoku Deluxe, Uni Sudoku or Snood Deluxe, which might be similar to brainworkshop.