After you activate the subconscience of the hyaline brain, scan your surroundings and you should see a sentinel marker with ancient site on it. Go to the ancient site and communicate with the structure and youll get the harmonic brain. The brains are in the sentinel ships that you get from dessonance spikes. Either find a harmonic camp where you can enter the correct runes (scan memory for the correct runes) or you can. De 2023 one of the obtained components from the ship is called a hyaline brain.
Will Contaminated Mycelium Fruit