The Apples in Stereo 1994-1995: Hypnotic Suggestion and Fun Trick Noisemaker
What is Hypnotic Suggestion?
What is Hypnotic Suggestion?
Several conflicts would lead Parfitt to leave the band in early 1994. John Hill, a former bandmate of McIntyre's, would join the band as a rhythm guitarist while Schneider began to grow more comfortable playing lead guitar. It was also at this time that Schneider began to take stronger creative control of the band, shifting its sound from its stronger rock qualities to a spacier pop sound. The band started work on a debut full-length album, but it instead became Hypnotic Suggestion, a second EP. However, after SpinART Records offered to buy the band an 8-track in return for an album, new plans for an LP arose.  In mid-1994, after Hypnotic Suggestion, McIntyre would be the second to leave the band, due to a number of personal distresses as well as stylistic changes that arose with Parfitt's departure. Having great difficulty finding a new permanent bassist, the band would rotate a number of frequent bass contributors, including Jeff Mangum of Neutral Milk Hotel, Kurt Heasley of The Lilys, Kyle Jones, Joel Richardson, and Joel Evans. Jim McIntyre would also occasionally guest on bass. This continued to be the makeup of the band as they toured the country in late 1994, recording the first half of their new album in Glendora, California. In early 1995, the band finished the album, Fun Trick Noisemaker, at Kyle Jones's house (the birthplace of Schneider's Pet Sounds Studio).  Now with a full-length LP to support, the band began touring again. Eric Allen, whom the band had previously auditioned as a guitarist after the departure of Chris Parfitt, joined the band as a much welcomed permanent bassist. Late 1995, Schneider relocated Pet Sounds Studio to Jim McIntyre's house. McIntyre continued to be involved in the recording and engineering of the band's albums until the mid-2000s.  A significantly different band from the original 1992 four-piece, the official name of the band gradually became "The Apples in Stereo", with the "in stereo" usually somewhat under-emphasized, whether in lower-case or in parentheses. Schneider described this in an interview: "It's very clearcut, actually: we're The Apples, the music's in stereo. It's not actually the band name - it's a step back from it, a band name once removed. We're The Apples, in stereo. Kind of like a TV show, 'in stereo!' That always seemed to be a really big deal, that it was in stereo." McIntyre later remarked, "It's cool the name changed cause the Apples and the Apples in Stereo were really two different entities." CANNOTANSWER
The band started work on a debut full-length album, but it instead became Hypnotic Suggestion, a second EP.
The Apples in Stereo, styled as The Apples in stereo, are an American rock band associated with Elephant Six Collective, a group of bands also including Neutral Milk Hotel, The Olivia Tremor Control, Elf Power, Of Montreal, and Circulatory System. The band is largely a product of lead vocalist/guitarist/producer Robert Schneider, who writes the majority of the band's music and lyrics. Currently, The Apples in Stereo also includes longstanding members John Hill (rhythm guitar) and Eric Allen (bass), as well as more recent members John Dufilho (drums), John Ferguson (keyboards), and Ben Phelan (keyboards/guitar/trumpet).

The band's sound draws comparisons to the psychedelic rock of The Beatles and The Beach Boys during the 1960s, as well as to bands such as Electric Light Orchestra and Pavement, and also draws from lo-fi, garage rock, new wave, R&B, bubblegum pop, power pop, punk, electro-pop and experimental music.

The band is also well known for their appearance in a The Powerpuff Girls music video performing the song "Signal in the Sky (Let's Go)". It aired immediately after the show's seventh episode of season 4, "Superfriends", which was based on the song's lyrics. The band has appeared widely in television and film, including performances on The Colbert Report, Late Night with Conan O'Brien and Last Call with Carson Daly, guest hosting on MTV, song placements in numerous television shows, commercials and motion pictures, the performance of the single "Energy" by the contestants on American Idol, and a song recorded for children's show Yo Gabba Gabba.

Band history

1991–1993: The Apples 
In late 1991, Robert Schneider met Jim McIntyre on a commuter bus in Denver, Colorado. Schneider had recently moved to Colorado from Ruston, Louisiana, and often initiated conversations with McIntyre.  When Schneider asked McIntyre what his music interests were, McIntyre named his favorite band: The Beach Boys — a band Schneider was particularly fond of.  Realizing that they shared many musical interests, McIntyre introduced Schneider to Hilarie Sidney.  McIntyre already had a band called Von Hemmling in which McIntyre played bass and Sidney played drums. With Schneider, they discussed the idea of starting a band and perhaps a recording label.  Schneider later met Chris Parfitt, who at the time was also already in a band (which Schneider unsuccessfully auditioned for on bass). Schneider and Parfitt also became friends, however, and toyed with the idea of having a rock band similar to The Velvet Underground or Black Sabbath, with production qualities similar to that of The Beach Boys.

Schneider then spent two weeks in Athens, Georgia recording music and spending time with his childhood friends Will Cullen Hart, Bill Doss and Jeff Mangum. He discussed the idea of starting a record label with them (which soon became The Elephant 6 Recording Company). It was also at this time that the name "The Apples" came about, inspired by the Pink Floyd song "Apples and Oranges".

The earliest incarnation of the band began to form in 1992 upon Schneider's return to Denver, first between Schneider and Parfitt, both of whom played guitar.  The two recruited McIntyre and Sidney during the autumn of that year, practicing material through the winter.  Their first few live shows took place the following January, many of which were with the band Felt Pilotes. From February to April 1993, the band recorded their debut 7" EP, Tidal Wave, and released it in June as the first record ever to bear the Elephant 6 logo.

1994–1995: Hypnotic Suggestion and Fun Trick Noisemaker 
Several conflicts would lead Parfitt to leave the band in early 1994. John Hill, a former bandmate of McIntyre's, would join the band as a rhythm guitarist while Schneider began to grow more comfortable playing lead guitar. It was also at this time that Schneider began to take stronger creative control of the band, shifting its sound from its stronger rock qualities to a spacier pop sound. The band started work on a debut album, but it instead became Hypnotic Suggestion, a second EP. However, after SpinART Records offered to buy the band an 8-track in return for an album, new plans for an LP arose.

In mid-1994, after Hypnotic Suggestion, McIntyre would be the second to leave the band, due to a number of personal distresses as well as stylistic changes that arose with Parfitt's departure. Having great difficulty finding a new permanent bassist, the band would rotate a number of frequent bass contributors, including Jeff Mangum of Neutral Milk Hotel, Kurt Heasley of The Lilys, Kyle Jones, Joel Richardson, and Joel Evans. Jim McIntyre would also occasionally guest on bass.  This continued to be the makeup of the band as they toured the country in late 1994, recording the first half of their new album in Glendora, California.  In early 1995, the band finished the album, Fun Trick Noisemaker, at Kyle Jones's house (the birthplace of Schneider's Pet Sounds Studio).

Now with a LP to support, the band began touring again. Eric Allen, whom the band had previously auditioned as a guitarist after the departure of Chris Parfitt, joined the band as a much welcomed permanent bassist. Late 1995, Schneider relocated Pet Sounds Studio to Jim McIntyre's house. McIntyre continued to be involved in the recording and engineering of the band's albums until the mid-2000s.

A significantly different band from the original 1992 four-piece, the official name of the band gradually became "The Apples in Stereo", with the "in stereo" usually somewhat under-emphasized, whether in lower-case or in parentheses.  Schneider described this in an interview: "It's very clearcut, actually: we're The Apples, the music's in stereo.  It's not actually the band name – it's a step back from it, a band name once removed. We're The Apples, in stereo. Kind of like a TV show, 'in stereo!'  That always seemed to be a really big deal, that it was in stereo." McIntyre later remarked, "It's cool the name changed cause the Apples and the Apples in Stereo were really two different entities."

1996–2005: Tone Soul Evolution to Velocity of Sound
The band continued touring through 1996, playing in Japan for the first time. Several early recording sessions were held at Pet Sounds for the band's second album, Tone Soul Evolution, but the members were dissatisfied with the quality of the recordings. The majority of the album's songs were re-recorded at Studio .45 in Hartford, Connecticut before the album's release. In 1998, Chris McDuffie joined the band, playing various instruments including organs, synthesizers and assorted percussion. He would leave the band before Velocity of Sound was released in 2002.

Several more albums were released by the band through the years, including the psychedelic "concept EP", Her Wallpaper Reverie, The Discovery of a World Inside the Moone and Velocity of Sound; both of the latter of which were progressively aimed at capturing the live sound of the band, which continued to tighten as they continued to perform hundreds of live shows (about 100 a year). In particular, the 2002 album Velocity of Sound rejects most of the psych-pop production sensibilities that would come to be associated with the band, instead featuring stripped-down production and sparse, rock instrumentation.

The band members would also continue to pursue careers in side bands and solo projects, with Schneider producing several albums for Elephant 6 artists. Schneider and drummer Hilarie Sidney were married for a time, with a son Max born in 2000. They have since been divorced.

The band went on a brief hiatus during 2004 as Schneider released the debut album from a new band called Ulysses and Sidney released the debut album from her new band The High Water Marks; both were released on Eenie Meenie Records. In 2005, The Apples in Stereo contributed "Liza Jane" to the Eenie Meenie compilation, Dimension Mix. It was also around this time that news began to circulate among various websites concerning the band's next studio album.

2006–2008: New Magnetic Wonder and evolving lineup

In August 2006, longtime drummer Hilarie Sidney officially announced her departure from the band during the band's closing set at the Athens Popfest music festival in Athens, Georgia. Her replacement, John Dufilho, lead singer and principal songwriter of The Deathray Davies, was announced in October 2006. 2006 touring member Bill Doss of The Olivia Tremor Control also quietly joined the band "officially" as its new keyboardist. John Ferguson of Big Fresh and Ulysses joined the Apples in 2007, also playing keyboards, and wearing a Doctor Who-esque space suit on stage.

In December 2006, Robert Schneider appeared on the popular television show The Colbert Report singing the song "Stephen Stephen" recorded by The Apples in Stereo to glorify the show's host Stephen Colbert, to kick off a guitar solo contest between Colbert and Chris Funk of The Decemberists.

On February 6, 2007, The Apples in Stereo released their sixth studio LP, New Magnetic Wonder. Finishing a ten-year deal with spinART Records, New Magnetic Wonder was the premiere release on Simian Records, a newly formed record label founded by Elijah Wood. This was followed by a long-awaited b-sides and rarities compilation titled Electronic Projects for Musicians, released on April 1.

In 2008, spinART Records went out of business. Rights for all major releases by The Apples in Stereo on the label were subsequently acquired by One Little Indian Records, and have since reverted to the band. In a recent interview, Schneider noted that the band's EPs have yet to have been re-released, but will likely be collected for another compilation. Such a compilation would probably include the re-releases of Look Away + 4, Let's Go! and a number of non-album songs released alongside New Magnetic Wonder.

On August 4, 2008, the band appeared again on The Colbert Report. They performed their song Can You Feel It? to promote the release of the Japanese picture disc.

In early 2008, their song "Same Old Drag" won in The 7th Annual Independent Music Awards for Best Pop/Rock Song. The same year Apples in Stereo were nominated for Independent Music Awards Pop/Rock Album of the Year. The band members also joined the 9th annual Independent Music Awards judging panel to assist independent musicians' careers.

2009–2011: #1 Hits Explosion and Travellers in Space and Time

Yep Roc released #1 Hits Explosion, an Apples in Stereo best-of album, on September 1, 2009.

In late 2008, PepsiCo released an advertisement with their song "Energy" off of their album New Magnetic Wonder.

In early 2009, Robert appeared on ABC News's segment called "amplified" and gave some short performances of songs from New Magnetic Wonder and a song from his project "Robert Bobbert and the bubble machine" and he described the album as sounding like early 1970s R&B as it would sound played by aliens and emanating from an alien spaceship.He also confirmed that the band was recording their new album at Trout Recording in Brooklyn, New York. In interviews in Billboard magazine and other press outlets,

In April 2009, the single "Energy" from New Magnetic Wonder was performed by the contestants on the television show American Idol.

The result was the band's seventh album Travellers in Space and Time, released on April 20, 2010 on Simian Records. Described by Schneider as a "retro-futuristic" concept album intended as a time capsule for listeners of the future, Travellers has drawn comparisons to the style of Electric Light Orchestra. The record is the first Apples in Stereo album without Hilarie Sidney, making Schneider the last founding member remaining in the group, although John Hill joined before "in stereo" was added to the name. The band was invited by Jeff Mangum of Neutral Milk Hotel to perform at the All Tomorrow's Parties festival that he curated in March 2012 in Minehead, England.

Schneider announced in May 2012 that The Apples in Stereo had begun work on a new album, described as being "a very, very different sort of album."

In recent years, Schneider has explored a number of experimental music projects, such as the Teletron mind-controlled synthesizer and Non-Pythagorean scale of his own invention.

2012–present: Death of Bill Doss, hiatus and future
The death of Bill Doss, the band's keyboardist as well as the co-founder of fellow Elephant 6 band The Olivia Tremor Control, was announced on July 31, 2012. The cause of death was an aneurysm. Schneider released a statement saying, "I am heartbroken by the loss of my life-long friend, collaborator and band-mate. My world will never be the same without the wonderful, funny, supremely creative Bill Doss."

The band went into hiatus in the fall of 2012, after Doss' death and Schneider's acceptance into the PhD program in Mathematics at Emory University. In 2013, Phish started covering the Apples in Stereo song "Energy."

In early 2017, Schneider hinted at a new album called The Bicycle Day. He stated on Facebook that "Apples are working on a concept record called The Bicycle Day but it is too deep of a task to finish while I'm in graduate school... it isn't a pop record though ... (Air-Sea Dolphin and my band Spaceflyte with John Ferguson are the new pop projects though)". On August 10, 2017, the Apples played their first show since 2012 as a headlining act at the Athens Popfest music festival in Athens, Georgia with Marshmallow Coast, Antlered Auntlord, and Waxahatchee as prior performers.

In 2018, Schneider received a PhD in mathematics from Emory.

Band members 
Current members                                          
 Robert Schneider - guitar, French horn, lead vocals (1992–present)
 John Hill - guitar, xylophone (1994–present)
 Eric Allen - bass, harmonica (1995–present)
 John Dufilho - drums, harp (2006–present)
 John Ferguson - vocals, keyboards, panflute (2007–present)

Former members
 Hilarie Sidney - drums, vocals (1992-2006)
 Jim McIntyre - bass (1992-1994)
 Chris Parfitt - guitar (1992-1994)
 Chris McDuffie - keyboards (1998-2002)
 Bill Doss - vocals, keyboards, ukulele (2006-2012; died 2012)

Timeline

Selected discography 

 Fun Trick Noisemaker (1995)
 Science Faire (1996)
 Tone Soul Evolution (1997)
 Her Wallpaper Reverie (1999)
 The Discovery of a World Inside the Moone (2000)
 Velocity of Sound (2002)
 New Magnetic Wonder (2007)
 Electronic Projects for Musicians (2008)
 Travellers in Space and Time (2010)

References

External links 
 
 The Apples in Stereo at Elephant6.com
 Tractor Beam Management
 
 Apples in Stereo entry at Trouser Press
 The Apples in Stereo at Live Music Archive
 Interview with the Cornell Daily Sun
 Step Through the Portal

The Elephant 6 Recording Company artists
Musical groups from Denver
Lo-fi music groups
Musical groups established in 1992
Independent Music Awards winners
Indie pop groups from Colorado
Indie rock musical groups from Colorado
Psychedelic pop music groups
American power pop groups
SpinART Records artists
Yep Roc Records artists
Suggestion is the psychological process by which a person guides their own or another person's desired thoughts, feelings, and behaviors by presenting stimuli that may elicit them as reflexes instead of relying on conscious effort.

Nineteenth-century writers on psychology such as William James used the words "suggest" and "suggestion" in the context of a particular idea which was said to suggest another when it brought that other idea to mind. Early scientific studies of hypnosis by Clark Leonard Hull and others extended the meaning of these words in a special and technical sense (Hull, 1933).

The original neuropsychological theory of hypnotic suggestion was based upon the ideomotor reflex response that William B. Carpenter declared, in 1852, was the principle through which James Braid's hypnotic phenomena were produced.

Émile Coué 
Émile Coué (1857–1926) was a significant pioneer in the development of an understanding of the application of therapeutic suggestion; and, according to Cheek and LeCron, most of our current knowledge of suggestion "stems from Coué" (1968, p.60). With the intention of "saturating the cognitive microenvironment of the mind", Coué's therapeutic method approach was based on four non-controversial principles:
(1) suggestion can produce somatic phenomena;
(2) specific suggestions generate specific somatic outcomes;
(3) suggestions are just as efficacious in the treatment of physical or organic conditions as they are for functional or emotional conditions; and
(4) a successful suggestion-based intervention for a physical condition does not indicate that the original complaint was in any way imaginary. 

Coué's laws of suggestion. Ideomotor and ideosensory effect.  (Suggestion and Autosuggestion, Baudouin, C. 1920: 117).
1. The Law of Concentrated Attention

If spontaneous attention is concentrated on an idea, this tends to become realized.

2. The Law of Auxiliary Emotion, also called the Law of dominant effect When a suggestion is supported by emotion it will become stronger than every other suggestion, given at the same moment.

3. The Law of Reversed Effort

 If conscious will is in conflict with fantasy, the fantasy will win.

4. The Law of Subconscious Teleology

When the goal has been traced out the unconscious will find out how to reach it.

“When the end has been suggested the subconscious finds means for its realisation.”

To be realized an idea must be unconsciously processed and accepted. The mechanism is the same as in motivation.

Hypnosis

Trance and suggestion
Modern scientific study of hypnosis, which follows the pattern of Hull's work, separates two essential factors: "trance" and suggestion. The state of mind induced by "trance" is said to come about via the process of a hypnotic induction—essentially instructing and suggesting to the subject that they will enter a hypnotic state. Once a subject enters hypnosis, the hypnotist gives suggestions that can produce sought effects. Commonly used suggestions on measures of "suggestibility" or "susceptibility" (or for those with a different theoretical orientation, "hypnotic talent") include suggestions that one's arm is getting lighter and floating up in the air, or that a fly is buzzing around one's head. The "classic" response to an accepted suggestion that one's arm is beginning to float in the air is that the subject perceives the intended effect as happening involuntarily.

Scientific hypnotism
Consistent with the views of Pierre Janet—who noted (1920, pp.284–285) that the critical feature is not the making of a 'suggestion', but, instead, is the taking of the 'suggestion'—Weitzenhoffer (2000, passim), argued that scientific hypnotism centres on the delivery of "suggestions" to hypnotized subjects; and, according to Yeates (2016b, p.35), these suggestions are delivered with the intention of eliciting:
(1) the further stimulation of partially active mental states and/or physiological processes;
(2) the awakening of dormant mental states and/or physiological processes;
(3) the activation of latent mental states and/or physiological processes;
(4) alterations in existing perceptions, thoughts, feelings, and/or behaviours; and/or
(5) entirely new perceptions, thoughts, feelings, and/or behaviours.

Temporal dimensions
Furthermore, according to Yeates (2016b, pp.35–36), 'suggestions' have four temporal dimensions: 
(1) pre-hypnotic suggestions, delivered prior to the formal induction;
(2) suggestions for within-hypnotic influence, to elicit specific within-session outcomes;
(3) suggestions for post-hypnotic influence, to elicit specific post-session outcomes:
(i) immediate influence ("and, on leaving here today, you'll…");
(ii) shorter-term influence ("and, each time you're…");
(iii) longer-term influence ("and, as time passes, you'll increasingly…"); or
(iv) specific-moment influence (Bernheim's suggestions à longue échéance, 'suggestions to be realised after a long interval'), which are (i) intended "to produce a particular effect at a designated later hour", (ii) have "no influence before the appointed hour", (iii) nor "after it had expired" (Barrows, 1896, pp.22–23), or
(4) post-hypnotic suggestions, delivered to dehypnotised-but-not-yet-completely-reoriented subjects.

Waking suggestion
Suggestions, however, can also have an effect in the absence of a hypnosis. These so-called "waking suggestions" are given in precisely the same way as "hypnotic suggestions" (i.e., suggestions given within hypnosis) and can produce strong changes in perceptual experience. Experiments on suggestion, in the absence of hypnosis, were conducted by early researchers such as Hull (1933). More recently, researchers such as Nicholas Spanos and Irving Kirsch have conducted experiments investigating such non-hypnotic-suggestibility and found a strong correlation between people's responses to suggestion both in- and outside hypnosis.

Other forms
In addition to the kinds of suggestion typically delivered by researchers interested in hypnosis there are other forms of suggestibility, though not all are considered interrelated. These include: primary and secondary suggestibility (older terms for non-hypnotic and hypnotic suggestibility respectively), hypnotic suggestibility (i.e., the response to suggestion measured within hypnosis), and interrogative suggestibility (yielding to interrogative questions, and shifting responses when interrogative pressure is applied: see Gudjonsson suggestibility scale. Metaphors and imagery can also be used to deliver suggestion.

See also 

Affirmations
Attitude
Autosuggestion
Autogenic training
Crowd manipulation
Hypnosis
Hypnotic susceptibility
Nancy School
Neuro-linguistic programming
Posthypnotic amnesia
Psychosomatic medicine
The Salpêtrière School of Hypnosis
Self-hypnosis
Subconscious
Suggestibility

Footnotes

References
 Barrows, C.M., "Suggestion Without Hypnotism: An Account of Experiments in Preventing or Suppressing Pain", Proceedings of the Society for Psychical Research, vol.12, No.30, (1896), pp.21–44.
  V. M. Bekhterev "Suggestion and its Role in Social Life" with a Preface by José Manuel Jara Italian edition, Psichiatria e Territorio, 2013.
 Cheek, D.B., & LeCron, L.M., Clinical Hypnotherapy, Grune & Stratton (New York), 1968.
 Janet, P., "Lecture XIII: The Hysterical Stigmata—Suggestibility", pp.270–292 in P. Janet, The Major Symptoms of Hysteria: Fifteen Lectures Given in the Medical School of Harvard University, Second Edition with New Matter, Macmillan Company, (New York), 1920.
 
 Weitzenhoffer, A.M., The Practice of Hypnotism (Second Edition), John Wiley & Sons (New York), 2000.
 Yeates, L.B., James Braid: Surgeon, Gentleman Scientist, and Hypnotist, Ph.D. Dissertation, School of History and Philosophy of Science, Faculty of Arts & Social Sciences, University of New South Wales, January 2013.
 Yeates, Lindsay B. (2016a), "Émile Coué and his Method (I): The Chemist of Thought and Human Action", Australian Journal of Clinical Hypnotherapy & Hypnosis, Volume 38, No.1, (Autumn 2016), pp.3–27.
 Yeates, Lindsay B. (2016b), "Émile Coué and his Method (II): Hypnotism, Suggestion, Ego-Strengthening, and Autosuggestion", Australian Journal of Clinical Hypnotherapy & Hypnosis, Volume 38, No.1, (Autumn 2016), pp.28–54.
 Yeates, Lindsay B. (2016c), "Émile Coué and his Method (III): Every Day in Every Way", Australian Journal of Clinical Hypnotherapy & Hypnosis, Volume 38, No.1, (Autumn 2016), pp.55–79.

External links

 , Chautauqua Institution
 The Power of Suggestion: What We Expect Influences Our Behavior, for Better or Worse
 Exploring the science behind hypnosis

Hypnosis
Sentences by type 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. Individuals who are experiencing post-hypnotic amnesia cannot have their memories recovered once put back under hypnosis and 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. It has been suggested that inconsistencies in methodologies used to study post-hypnotic amnesia cause varying results.

History
Post-hypnotic amnesia was first discovered by Marquis de Puységur in 1784. When working with his subject Victor, Puységur noticed that when Victor would come out of hypnosis he would have amnesia for everything that had happened during the session. Recognizing the importance of this power, Puységur soon began treating those who were ill with induced amnesia. When French physician Ambroise-Auguste Liébeault published a book on hypnotism in 1866 he proposed that post-hypnotic amnesia was a "symptom" and a varying degree of hypnotism.
Similarly, 19th century French neurologist Jean Martin Charcot focused solely on post-hypnotic amnesia. Charcot introduced three states of hypnosis:  fatigue, catalepsy, and somnambulism, or sleepwalking; it was within this last state that Charcot believed individuals could be communicated to and could respond to suggestions. Charcot showed that if an individual (through post-hypnotic suggestion) self-suggested that they had a psychological trauma, those who were neurologically susceptible would display symptoms of psychological trauma. It was hypothesized that this was due to the dissociation of the ideas from the rest of the individual's consciousness. However, dissociation theory was put aside for Freud's psychoanalytic theory and the rise of behaviourism until Ernest Hilgard renewed its study in the 1970s.

Some of the earliest experimental studies on post-hypnotic amnesia were done by Clark Hull (1933). Hull's work showed that there was dissociation between explicit memory and implicit memory through studies on proactive interference and retroactive interference, pair associations and complex mental addition.

In the mid-1960s, Evan and Thorn produced studies on source amnesia. In one study hypnotized individuals were taught answers to obscure facts and when brought out of their hypnotized states, one third of the individuals were able to produce the correct answers. Nevertheless, these same individuals had no conscious memory of where they learned this material.

Categories
Spontaneous and suggested post-hypnotic amnesia can occur or be induced in an individual.

Spontaneous
For most of the 19th century, investigators reported that post-hypnotic amnesia only occurred spontaneously as scientific knowledge regarding this form of amnesia was minimal. Spontaneous post-hypnotic amnesia represents a slight memory impairment that results as a consequence of being put under hypnosis or being tested. This form of amnesia can also be experienced across susceptibility groups, but to a much lesser extent and magnitude to suggested post-hypnotic amnesia.

Spontaneous amnesia has also been difficult to determine as research bias has been found to influence in many cases. In one study participants were put into two groups; one was to receive amnesic instructions and half were not given the instructions. The next day the groups were reversed. Results showed that there was little spontaneous amnesia across all participants, leading to doubts towards the actual occurrence of amnesia. It was later found that those more susceptible to hypnosis were more susceptible to suggested post-hypnotic amnesia and not spontaneous amnesia. These results suggest that spontaneous amnesia is less common than suggested amnesia and that when high results of spontaneous amnesia are recorded, some incidences may be false.

Suggested
Suggested post-hypnotic amnesia involves the suggestion to hypnotized persons that following hypnosis they will be unable to accurately recall specific material (e.g. stimuli or events learned while under hypnosis) until they receive a reversibility cue. This type of post-hypnotic amnesia is the most commonly used within research surrounding post-hypnotic amnesia due to its controlled nature.

Suggested amnesia has been found to result in a more significant memory loss than spontaneous amnesia, regardless of the order of induction. On average, more individuals experience suggested amnesia and there appears to be a moderate effect across individuals of all levels of hypnotic susceptibility. Suggested post-hypnotic amnesia also involves a "temporary, retrieval-based dissociation between episodic and semantic memory". However, it is more common for highly hypnotizable individuals to remember less information than low hypnotizable individuals or controls while under suggested post-hypnotic amnesia.

Post-hypnotic amnesia is reversible, a characteristic that distinguishes it from other forms of amnesia that arise primarily from traumatic brain injury. Whereas the retrieval of memories under retrograde amnesia is a slow and labour-intensive process, the reversal of hypnotically-induced amnesia can occur with a simple suggestion or reversal cue (e.g., "when I clap my hands, you will remember everything").

Types

Recall amnesia
Post-hypnotic recall amnesia refers to an individual's inability to recall, when in a normal conscious state, the events that occurred during hypnosis.  Evidence for this type of post-hypnotic amnesia is seen in a typical research model testing where nonsense syllables, that were paired during hypnosis, are unable to be recalled post hypnotically when a suggestion for amnesia was given during hypnosis.  Recall amnesia for word associations tend to be very high when done by post-hypnotic individuals, with some studies showing one hundred percent total recall amnesia. This amnesia can also be measured by asking individuals, after their hypnosis has been terminated, to describe what they have been doing since they first laid down on the couch for their hypnosis session.  When using this method for experimental testing, the hypnosis session will typically involve several tests or activities that the subject will engage in.  Recall amnesia can then be measured by the amount of accurate tasks and activities the subject is able to remember.

Recognition amnesia
Recognition amnesia equates to an impairment of an individual's recognition memory brought on by amnesia. As event-related potentials have been found to be sensitive to familiar stimuli in the absence of recognition impairments it has been suggested that individuals who report amnesia after hypnosis might not be experiencing post-amnesia recognition impairments. Instead, they may not be accurately describing their experience and confuse having amnesia for a lack of attention during encoding of tested stimuli.

Source amnesia
Post-hypnotic source amnesia refers to the ability of individuals to correctly recall information learned during hypnosis without the recollection of where the information was acquired. In a typical study examining this type of amnesia, individuals are administered a hypnotic induction procedure which is immediately followed by a series of questions concerning unfamiliar facts, for example "what year was Freud born in?".  Subjects who are unable to correctly answer these questions are informed of the correct answers.  These individuals are then administered a suggestion to be amnesic for everything that occurred during the period of which they are hypnotized.  After the hypnotic session, those who exhibit post-hypnotic source amnesia, when asked the same unfamiliar questions again, will respond with the correct answers but will not be able to state where they learned the answer, or, more commonly, rationalize an incorrect source of their answer.

Models and theoretical explanations

Dissociation
Dissociation, a theory originally applied by Pierre Janet, implies the view of the conscious self as being totally suspended. Dissociation, when referring to post-hypnotic amnesia, can be applied when the whole period in which an individual is hypnotized is looked at as an episode that is separated from the rest of that individual's experiences by boundaries of amnesia and suggestion.  The failure to recall memory when in a normal, conscious state provides evidence to suggest that some kind of functional barrier is holding the information retained during hypnosis back from conscious recall.  However, how sufficient the dissociative barrier in a hypnotic patient's mind is seems to be not all that effective, thus diminishing the credibility of the dissociation theory.  This is easily seen in several studies where engaging in a secondary hypnotic session or the suggestion of the hypnotist or therapist to retrieve and recall information and events from the hypnotic session, readily and accurately initiate the retrieval that, according to dissociation, should be blocked from retrieval.

Disrupted retrieval
This theory proposes that when it comes to post-hypnotic amnesia, individuals are unable to recall efficiently and accurately the events that took place while they were hypnotized because there is a greater degree of overall disruption in the retrieval of their hypnosis events. This temporary disruption in retrieval is typically due to the induced amnesic suggestion that a hypnotists or therapist will usually give during the session.  Studies have been able to demonstrate this theory showing that hypnotizable subjects tend to recall events, if they even can, in a random, unassociated fashion, whereas subjects who did not receive a hypnotic suggestion for amnesia are able to recall in an orderly sequenced manner, starting with the original event of hypnosis and then recalling succeeding events in the correct order as they occurred.  Results support this theory by indicting that effective retrieval cues, such as the temporal sequence of events, may not be being used successfully while under hypnosis compared to when they are used by individuals in a normal, waking state.  As a result, a disruption in memory recollection which is characteristic of post-hypnotic amnesia appears.

Verbal inhibition model
This theory on post-hypnotic amnesia argues that individuals who have been hypnotized actually do have the ability to remember material from their hypnosis sessions. However, these individuals simply inhibit their verbal report of that information. It is believed that the material learned while under hypnosis is activated and retrieved into working memory where it is then processed and checked to see if it is material that can or should be remembered or if it is material that is forbidden and should therefore be forgotten.  If the material is deemed forbidden, this theory suggests that the material is denied verbal output and sometimes even admission into an individual's conscious awareness.

Effects and impact

Cognitive
Many theorists believe that explicit and implicit memory are separate memory systems in the brain. However, much research on explicit and implicit memory in post-hypnotic amnesia has shown that if they are separate areas, they interact often and in a variety of ways. Attention, selection, and accessibility of information are processes thought to be involved in the phenomenon of posthypnotic amnesia, and when tested, post-hypnotic amnesia has shown to cause dissociation between both implicit and explicit expressions of memory. In observing dissociation in post-hypnotic amnesia there are three aspects that differentiate it from other forms of amnesia. Firstly, items are deeply processed during encoding. Secondly, individuals are semantically primed – this relies on deep encoding and preserved cue retrieval. Thirdly, the impairment of the explicit memory is only temporary; implicit memories can be restored to explicit when given the reversible prearranged cue. Research has found that the memory of individuals who are very highly susceptible to hypnotism is more influenced by implicit effects (word-stem completions, word associations and lexical decision tasks) than explicit effects (recognition tasks) Those posthypnotic subjects who have no explicit memory of cues learned under hypnosis have been found to generate many of these explicit cues in free association tests.

A post-hypnotic suggestion to forget can also successfully cause a deficit in autobiographical memory. Results from Barnier's study associating post-hypnotic amnesia and autobiographical supported previous findings regarding a dissociation between explicit and implicit memory, as well as impaired explicit recall – traits common to Psychogenic amnesia. After the suggested instructions to elicit post-hypnotic amnesia were administered, those participants that were highly susceptible to hypnosis showed more impaired recall of the autobiographical episode targeted by the suggestion, with both groups providing substantial information for the more recent autobiographical episode. Additionally, information from the "forgotten" episode (demonstrating implicit memory) influenced overall performance on the category-generation and social judgement tasks aimed at testing each participant's explicit memory.

Biological
post-hypnotic amnesia is characterized as a "retrieval deficit", whereas other types of amnesia suffer from a "storage" deficit (e.g. Anterograde amnesia). post-hypnotic amnesia has been correlated with reduced cortical activity in the occipital and temporal cortex, while showing an increase in activation in the prefrontal cortex. It has been suggested that some of 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

See also
Amnesia
False memory syndrome
Hypnosis in popular culture
Hypnotherapy
Psychogenic amnesia
Recovered memory therapy
Retrograde amnesia

References

Hypnosis
Amnesia