|To master all the brain quadrants you will need to play Take-A-Test mode over and over again. Depending on what mini-games you get by answering questions either correctly or incorrectly each brain quadrant will either increase or decrease respectively. The four brain quadrants are Calculus Noggin(Green), Archivous Oblongata(Yellow), Twitchim Lobe(Blue) and Sequential Quartex(Pink). You can view your performance for each quarter by going into ‘Test Results’ in the single player menu.|
This achievement can be obtained on any difficulty but the higher difficulty you play on then the bigger the chart increases or decreases, so there can be quite a lot at stake when playing on Enclevered difficulty. To avoid your performance chart decreasing, I would suggest playing on Medium difficulty, the puzzles are still fairly simple but your performance chart will increase by a significantly larger amount than it would on Easy difficulty.
The achievement will finally unlock when each quarter of the brain has reached the top of the ‘Test Results’ chart. The line will not be completely at the top of the graph, it will be very close to the top, but not touching it.