It is known that because of the breaking, sparks of Kedusha fell into BYA. But there, in BYA, they cannot be corrected, and hence must be elevated to Atzilut. And by doing good deeds and Mitzvot with the aim to bring contentment to one’s Maker and not to oneself, these sparks rise to Atzilut. Then they are integrated in the Masach of the Upper One, at the Rosh of the degree, where the Masach remains in its eternity. And at that time there is a Zivug (spiritual coupling) on the Masach by the Hitkalelut (mixture/integration) of the sparks, and the Upper Light spreads through all the worlds according to the measure of the sparks that they have raised.
This is similar to the Hizdakchut (purification) of the Partzufim of Akudim. We learned that during its Hizdakchut, when the Light departs because of it, the Masach of the Guf ascends along with the Reshimot to Peh de Rosh. The reason is that when the lower one stops receiving, it is considered that it has been purified of its Aviut (will to receive). Hence, the Masach can rise back to Peh de Rosh, as its whole decline into the degree of Guf was because the Light expanded from Above downward, into the vessels of reception.
Also, the Rosh is always discerned as being from below upward, meaning in resistance to the expansion. And when the Guf stops receiving the Lights from Above downward because of the absence of the Masach that had been purified by the Bitush (beating) of the internal and the external, it is considered that the Masach de Guf has been purified of its Aviut, and ascended to the Rosh with the Reshimot.
Additionally, when one engages in Torah and Mitzvot in order to bestow and not to receive, through it, the sparks rise to the Masach in the Rosh,in the world of Atzilut (and they rise degree-by-degree until they arrive at the Rosh de Atzilut). And when they are integrated in that Masach, and the level of Light appears according to the size of the Masach, more Light is added in all the worlds. And man, too, who caused that betterment Above, receives illumination by having improved Above, in the worlds.