Non-Attachment is the key to the end of suffering, The nature of the MInd is Luminosity.
When you manage to let go of the wandering/wondering thought process and thinking in words, see the impermanence and n on-self nature of all your experiential information received through your 5 khandas, then maybe you might see a flash of light, a holographic vision, or other apparitions.. don't follow them, they are just states of your own mind projection. If you lay an interest in them you will lose the letting go experience and advance no further. Continue in non attached concentraion and you will unveil the great shining golden Void and enter into Nirvana