All human beings can and do mental telepathy with the spiritual world, whether they know they are doing so or not.
Mental telepathy is simply the ability to intellectually hear or to intellectually choose to connect our mind of our intellect of our Soul with another soul or souls in the non-material spiritual world. When we choose to do this with The Divine/God or anyone fully united with Him such as our "guardian angel" or a saint recognized by the Catholic Church, it is known by the term "prayer". The term "Contemplative Prayer" is the term used to mean choosing to listen to The Divine/God or someone fully united with Him speak to us.
If and when a thought suddenly occurs or "pops" into our conscious-awareness and we truly did not choose to think with our free will, this occurs because we are hearing someone speak to us from the spiritual world, either The Divine/God or someone (an angel or deceased human being) united with Him, or we are hearing an evil spirit (demon) who is completely separated from The Divine/God. This is what modern psychology and psychiatry wrongly label as "auditory hallucinations".