Semantic memory holds the knowledge of the words' Alpha ZXT meanings and significance while episodic memory holds  context in the past. Frontal function in long-term memory encoding involves the recovery of moments from past experiences that were forgotten. According to early studies, memory encoding showed evidence for the engagement of left frontal cortex on the retrieval of memories. http://www.healthsupreviews.com/is-alpha-zxt-scam-or-legit/