Biologically threatening events and severe psychological traumas in early infancy seem to represent a thematic link between the biographical level and the perinatal level of the unconscious.
Grof identifies the biographical level as a distinct stratum of the unconscious that is structurally contiguous with the perinatal level, with early somatic trauma serving as the experiential bridge between the two.
, LSD Psychotherapy: The Healing Potential of Psychedelic Medicine, 1980thesis