My mother died and when I am alone I see her before me, as if she is with me, and she informs me of incidents that take place afterwards. Given the fact that the spirit ascends to its Creator (Allaah), how do you explain what is happening? What are the actions that I may benefit my parents with?

All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and messenger.

Undoubtedly, after death a person enters the life of the grave that starts with death and goes until the Hour of Judgment. This life is totally separate from this worldly life, as Allaah Says (what means): {And behind them is a (Barzakh) barrier until the Day they are resurrected.}[Quran 23:100] Thus, it is impossible to return to the worldly life.

As for the returning of a soul to this worldly life to address someone, then there is no evidence proving this in the Quran or the Sunnah. What you are experiencing may be from the devil companion who used to accompany your mother. On the authority of Ibn Mas‘ood the Prophet, sallallaahu ‘alayhi wa sallam, said that everyone has a companion from the Jinn, even he, sallallaahu ‘alayhi wa sallam, but Allaah helped him convert this Jinni companion to Islam, so he only orders the Prophet, sallallaahu ‘alayhi wa sallam, to do good.  [Ahmad and Muslim]

As for your duty towards your dead parents, stay dutiful to them by supplicating Allaah to forgive them, being kind to their friends, and maintaining their kinship ties.

Allaah Knows best.