Post-hypnotic amnesia is the inability in hypnotic subjects to recall events that took place while under hypnosis. This can be achieved by giving individuals a suggestion during hypnosis to forget certain material that they have learned, either before or during hypnosis.[1] Individuals who are experiencing post-hypnotic amnesia cannot have their memories recovered once put back under hypnosis; it is therefore not state-dependent. Nevertheless, memories may return when presented with a pre-arranged cue. This makes post-hypnotic amnesia similar to psychogenic amnesia, as it disrupts the retrieval process of memory.[2] It has been suggested that inconsistencies in methodologies used to study post-hypnotic amnesia cause varying results.[3]