these areas are involved in the retrieval of long term episodic memories, while others are involved in inhibiting this retrieval. various forms of functional amnesia have been suggested as the outcome of retrieval abortion and thus could be partially modeled using post-hypnotic amnesia (i.e. lower physical risk to the individual). for example, cases of post-hypnotic amnesia show strikingly similar cognitive and neurological characteristics to cases of functional amnesia. previous fmri studies indicate that individuals suffering from functional amnesia show reduced frontal lobe activity that could impair working memory and lexical tasks involving one's native language. the majority of what is understood on the neurological bases of post-hypnotic amnesia stems from an integral study completed by mendelsohn et al. two groups of participants viewed a narrative documentary. after one week participants were hypnotized while placed in an fmri scanner and initiated into a suggestive post-hypnotic amnesia state where they were told to forget the details of the movie until they received a reversal cue. during scanning, participants were tested twice for their memory on either the movie details or context in which the movie was shown. these two test times allowed for the acquisition of brain activity "maps" during and after post-hypnotic amnesia had been lifted. unlike in response to the movie questions, the context questions for both groups revealed several overlapping networks of activity, including visual, sensory and perceptual regions, the cerebellum, the parietal lobes, the superior frontal gyrus, and the inferior frontal gyrus. the post-hypnotic amnesia group showed reduced memory for the contents of the movie but not for context of viewing. these results identify specific circuits within the brain that regulate the suppression of long-term memory retrieval during post-hypnotic suggestion. sociological post-hypnotic amnesia has been induced as a protective measure to help some individuals limit their recall of traumatic experiences. it can be used to limit the magnitude of post-traumatic stress disorder symptoms (vivid memories and dreams), feelings of criminal victimization, the aftermath of natural disasters or the theory of ufo abductions. suggested post-hypnotic amnesia can be induced and left for long periods of time, depending on if the amnesia is significant in reducing specific symptoms or memories, the content of the repressed material or the individual's motivation to recall events. the amount of scientific research on the effectiveness of hypnosis as a treatment for different types of pain (e.g. burns, cancer-related) is extensive. landolt and milling (2011) completed an exhaustive literature search that investigated the efficacy of hypnosis on reducing labor and delivery pain after pregnancy, in comparison to alternative interventions. they found that self-induced hypnosis was consistently more effective than standard medical care, counselling and education classes in relieving pain. however, this review did not include details on the effect of post-hypnotic amnesia on labor and delivery pain. this may be due to ethical barriers of inducing amnesia to individuals who are pregnant as they tend to be classified under "vulnerable" participant criteria. additionally, hypnotic suggestion has been used on specific conversion and psychiatric disorders to limit pain (e.g. limb paralysis, functional pain, auditory hallucinations and paranoid delusions of control). the use of hypnosis and suggestion for individuals with neurological disorders should be investigated more thoroughly to discern whether this potential treatment is of a generalized nature. furthermore, the "experience" of hypnosis has consistently produced more accurate and realistic subjective reports than simply using one's imagination. future research on this matter may lend support to subjects under hypnosis experiencing a greater "virtual reality" than control subjects and thus encourage practical, therapeutic applications in a clinical setting. the influence of hypnosis and amnesia has been present in the media for decades, with more television shows and movies involving the phenomenon than ever before. some examples of these shows and movies include the mentalist, memento, 50 first dates, eternal sunshine of the spotless mind and captain newman, m.d. the impact of post-hypnotic amnesia in the media has been far less successful, a result of the unique nature of the phenomenon, a general lack of knowledge on the subject or the idea that more the well-known and understood topics of hypnosis and amnesia can provide more creative vision and expansion. one unique exception is the band post-hypnotic amnesia, who seemed to understand enough of the phenomenon to dedicate it as their musical identity. hypnosis in popular culture has more detailed listings of hypnosis in written works, film, television and online media. breaching to induce post-hypnotic amnesia, subjects are told that they will not be able to remember anything that has happened during their hypnosis until the hypnotist later gives a cue saying that they can remember. there are various breaching procedures when it comes to post-hypnotic amnesia. one breaching procedure, initially done by kenneth s. bowers, involved tricking participants into believing that the hypnosis experiment they were involved in had ended before the cue said to release their amnesia had been given. subjects who were hypnotized were told that the experiment had media-recognition testing, also known as the experiential analysis technique has also been used to breach post-hypnotic amnesia. when given a video replay of a hypnosis session, subjects using the experiential analysis technique are asked to stop the video of their hypnosis session whenever they want to comment on their experiences. the video replay is typically shown before the amnesia during hypnosis is lifted, which, according to the experiential analysis technique, should cause the most inflexible and rigid hypnotic demands to breach. criticisms three criticisms are commonly made about post-hypnotic amnesia. the first observes that those individuals who may have poorer memory retrieval in general will show higher incidences of post-hypnotic amnesia. psychologist a.g. hammer found that those who were poor at word associations in two successive tests were likely to be more amnesic in hypnosis experiments. the second recognizes that methodologies have been inconsistent across research, thus limiting the generalizability of findings. studies are often small and non-randomized, further limiting results. finally, theories used in post-hypnotic amnesia have also been open to criticisms. dissociation theory is criticized for its vague and inconsistent definition. its ambiguousness has caused some to use the term when another mechanisms could be found to be the cause. the idea that hypnotic suggestion can be used to make individuals consent to acts that they would not normally have in a non-hypnotic state has been a criticism of suggested post-hypnotic amnesia for many years. a manipulative hypnotist may be able to convince a hypnotized person (e.g. a woman) that she is "unable to resist unwanted sexual suggestions" from the hypnotist. this idea poses the possibility of using hypnosis and suggested post-hypnotic amnesia for coercion, such that the woman may be induced into a state that limits her future recall of any negative experiences had at the hand of the hypnotist. however, most individuals cannot be forced to behave in a way that is against their will (this varies according to the suggestibility of the individual). the use of hypnosis in the military (see under "military applications") has also been very controversial due to the idea that some soldiers may commit acts induced by hypnotic suggestion. however, many of the perceived "dangers" of hypnosis and post-hypnotic amnesia result from a lack of public education on the matter. for example, an interesting study conducted in 1964 involved the use of post-hypnotic amnesia to protect patients from the aftermath of "alien abductions". following suggested post-hypnotic amnesia to a couple that had apparently experienced abduction by extraterrestrials, results indicate that the recalled memories may have actually been unconsciously influenced by the nightmares of one of the subjects, leading to more controversy on the matter of abductions and the reliability of suggested post-hypnotic amnesia procedures