Thursday 22 November 2012

Stream of Consciousness - Update

I have updated my 'Stream of Consciousness' page with some new Thematic Apperception Test results. Basically, I have found a selection of TAT images (ones which seem to be the most commonly used, judging by my research on this subject) and I post them on my page and record my automatic, stream of consciousness response to each. I will stare at the image and then write my 'story' for about 10 minutes, without thinking about what I am writing or editing it in any way - I just let it pour out onto the screen (or paper) and take whatever organic form emerges naturally. The content of the written response 'story' apparently determines your character and psychological profile. I am unable to grade my own responses as of yet, but hopefully will find a way of analysing my output.

Please click on the page tab at the top of the screen or the links in this page to visit my TAT results.

Déjà vu & dream precognition

I constantly have dreams of a ‘Dream Town’ – which are recorded in this Blog. As previously explained, this ‘town’ feels familiar, homely – as if it is a real-life memory of a place I have visited before. However, the town I dream of does not seem to relate to any actual location I have lived in, or can remember visiting. One dream revealed the town name to possibly be Sudbury/Sudsbury – the name of two actual places in England, although I have been to neither and internet research revealed neither location corresponds to my dream experience. In other dreams, a recurrent theme is me attending a university or college in this ‘dream town’ – although the campus is nothing like either university I have actually attended. I really enjoy dreaming of this town, although I am left confused by the strength of my consistent, recurrent memories of somewhere I can’t actually recall or identify in my waking life. My fascination with this element of my dream experience led me to research the phenomena of déjà vu and precognitive dreaming. 

Psychologist Edward B. Tichener in A Textbook of Psychology (1928) explains déjà vu as an experience in which a person has a brief glimpse of an object or situation prior to the brain having completed a ‘construction’ of a full conscious perception of the experience. This ‘partial perception’ results in a false sense of familiarity – thus, an anomaly of memory (false impression of actual recall), as opposed to an act of ‘precognition’ or ‘prophesy’. The experience of déjà vu means that the sense of ‘recollection’ at the time is particularly compelling, but the circumstances of ‘previous experience’ (the event upon which the ‘memory’ is based) are perceived as uncertain or impossible to have actually occurred. The subject may exhibit a strong recollection of having the somewhat unsettling experience of déjà vu itself, but absolutely no recollection of the specifics of the events ‘remembered’, which results in an ‘overlap’ between the neurological systems responsible for short-term memory and long-term memory. This results in memories of recent events being erroneously perceived as having occurred in the past. One theory explaining this phenomenon suggests that events are stored in the memory before the conscious part of the brain is able to receive the information and correctly process it. Criticism of this theory points out that the brain is unable store information without a prior sensory input. Another theory suggests that the brain may process sensory input as a ‘memory-in-progress’ and that during the event itself, a person believes it to be a past memory. In a survey, Brown (2004) concluded that approximately two-thirds of the population has experienced déjà vu. 

Other theories of déjà vu also assert that this phenomenon is the result of a flaw in the functioning of the short-term/long-term memory stores. The basic idea is that there are portions of the brain that are specialised for the past, the present and the future. In general, the frontal lobes are concerned with the future; the temporal lobes are concerned with the past; and the underlying, intermediate portions (the limbic system) are concerned with the present. When these elements of the brain are functioning normally, in normal states of consciousness, the feeling that ‘something is going to happen’ will only come up when we are thinking about the future - worrying about it, anticipating it or making plans for it. The sense of the past will only come up when our memories have been triggered in some way. The structure that controls our consciousness when we are 'in the present are is the amygdale, which assigns an emotional 'tone' to our perceptions. The amygdala also recognises and processes the expressions on people's faces. Certain phrases or words evoke feelings of imminent danger and require appropriate responses, and the amygdala is specialised to provide them. For example, one mental function it participates in - the maintenance of the sense of self - is repeated 40 times per second. Each instance of the ‘self’ is able to manifest a new emotional response, but only if circumstances have changed - every 25 milliseconds. In fact, the duration of the 'present' in neurological terms is so brief that we don't experience it so much as remember it.

Short term-memory deals in periods of a few minutes and is mostly based in the hippocampus. We know this because problems with the hippocampus often lead to severe short-term memory problems. It helps us to stay oriented in time and function effectively – for example, hold a conversation, remember what we have just done or where we have been etc. 

Then there is long-term memory, which is 'seated' in the surface of the brain, along the bottom of the temporal lobes. The area has been called the parahippocampal cortex, and it is very closely connected to the hippocampus. Ordinarily, there is a fairly seamless integration of the past, present and the future. In simple terms, we experience something in the present, compare it to similar experiences in the past, and then decide how we will respond. The time frame can be very brief - even a few seconds. Once in a while, though, there can be too much communication between short-term and long-term memories. When this happens, then the present can feel like the past. If perceptions from the present are shunted through the parts of the brain that process memories from the past, those perceptions will feel like they are memories, and the person will feel that they are re-living a moment stored in long-term memory – i.e. déjà vu.

Early researchers tried to establish a link between déjà vu and serious psychopathology such as schizophrenia, anxiety, and dissociative identity disorder, but failed to find any diagnostic value. There does not seem to be a special association between déjà vu and psychiatric conditions. The strongest pathological association of déjà vu is with temporal lobe epilepsy - this correlation leading some researchers to speculate that the experience of déjà vu is possibly a neurological anomaly related to improper electrical discharge in the brain. As most people suffer a mild (i.e. non-pathological) epileptic episode regularly (i.e. a hypnagogic - the sudden ‘jolt’ that frequently, but not always, occurs just prior to falling asleep), it is conjectured that a similar (mild) neurological aberration occurs in the experience of déjà vu, resulting in an erroneous sensation of memory. Scientists have even looked into genetics when considering déjà vu. Now they may never find a gene for déjà vu, but one particular gene and its inheritance patterns do intrigue scientists. The gene's name is LGII. It lies on chromosome 10. Certain forms of the gene are associated with a mild form of epilepsy. Though by no means a certainty, déjà vu occurs often enough during seizures that researchers have reason to suspect a link. Certain drugs increase the chances of déjà vu occurring in the user – for example, some pharmaceutical drugs (when taken together) have also been implicated in the cause of déjà vu. Taiminen & Jääskeläinen (2001) reported the case of an otherwise healthy male who started experiencing intense and recurrent sensations of déjà vu upon taking the drugs amantadine and phenylpropanolamine together (to relieve flu symptoms). Due to the dopaminergic action of the drugs and previous findings from electrode stimulation of the brain (i.e. Bancaud et al 1994) Taiminen & Jääskeläinen speculate that déjà vu occurs as a result of hyperdopaminergic action in the mesial temporal areas of the brain. The similarity between a déjà vu eliciting stimulus and an existing (but different) memory trace may lead to the sensation of déjà vu. Thus, encountering something which evokes the implicit associations of an experience or sensation that cannot be remembered, may lead to déjà vu. In an effort to experimentally reproduce the sensation, Banister & Zangwill (1941) used hypnosis to give participants posthypnotic amnesia for material they had already seen. When this was later re-encountered, the restricted activation caused thereafter by the posthypnotic amnesia resulted in 3 of the 10 participants reporting what the authors termed ‘paramnesias’. 

Memory-based explanations may lead to the development of a number of non-invasive experimental methods by which a long sought-after analogue of déjà vu can be reliably produced that would allow it to be tested under well-controlled experimental conditions. Cleary (2008) suggests that déjà vu may be a form of familiarity-based recognition (recognition that is based on a feeling of familiarity with a situation) and that laboratory methods of probing familiarity-based recognition hold promise for probing déjà vu in empirical research. A recent study that used virtual reality technology to study reported deja vu experiences supported this idea. This virtual reality investigation suggested that similarity between a new scene's spatial layout and the layout of a previously experienced scene in memory (but which fails to be recalled) may contribute to the deja vu experience. When the previously experienced scene fails to come to mind in response to viewing the new scene, that previously experienced scene in memory can still exert an effect – i.e. a feeling of familiarity with the new scene that is subjectively experienced as a feeling of déjà vu, or of having been there before despite knowing otherwise. Another possible explanation for the phenomenon of déjà vu is the occurrence of ‘cyptomnesia’ - which is where information learned is forgotten but nevertheless stored in the brain and similar occurrences invoke the contained knowledge, leading to a feeling of familiarity because of the situation, event or emotional/vocal content. Some experts suggest that memory is a process of reconstruction, rather than a recall of fixed, established events. This reconstruction comes from stored components, involving elaborations, distortions and omissions. Each successive recall of an event is merely a recall of the last reconstruction. The proposed sense of recognition (déjà vu) involves achieving a good ‘match’ between the present experience and our stored data. This reconstruction however, may now differ so much from the original event that we ‘know’ we have never experienced it before, even though it seems similar. Some parapsychologists have advocated other interpretations of déjà vu. Fisher (1984), Ian Stevenson (1987) and other researchers have written that some cases of déjá vu might be explained on the basis of reincarnation. Anthony Peake (2012) has written that déjà vu experiences occur as people are living their lives not for the first time but at least the second.

The phrase ‘jamais vu’ is derived from the French, meaning ‘never seen before’. It is used to describe something highly familiar to the subject, which is not recognised, and is perceived as being experienced for the very first time, despite the subject rationally knowing that they have been in the same situation before. The subject momentarily fails to recognise something they already know. Jamais vu is sometimes associated with certain types of aphasia, amnesia, and epilepsy. Theoretically, as seen below, a jamais vu feeling in a sufferer of a delirious disorder or intoxication could result in a delirious explanation of it, such as in the Capgras delusion, in which the patient takes a person known by him or her for a false double or impostor. If the impostor is himself, the clinical setting would be the same as the one described as depersonalisation, hence jamais vus of oneself or of the very ‘reality of reality’, are termed depersonalisation (or surreality) feelings. Presque vu is similar, yet distinct from the phenomenon which is commonly referred to as ‘tip of the tongue’ syndrome (where a word or memory is just beyond the reach of the subject trying to remember and has to be ‘mined’ for). Presque vu translates as ‘almost seen’ and is an experience described as a sensation of being on the brink of an epiphany. Déjà entendu means ‘already heard’; whereas reja vu is the feeling that something has happened or is imminent. 

Déjà vu in dreams is often written about in conjunction with ‘precognition’, but the two are very distinct concepts. In parapsychology, ‘precognition’ translates from the Latin prae (before) and cognito (acquiring thought) – and is also referred to as ‘future sight’ or ‘second sight’ – an extrasensory perception (ESP) by which the subject perceives knowledge or insight which cannot be obtained from present sensory, environmental or natural sources. A ‘premonition’ and ‘presentiment’ are types of knowledge/information about future events which is perceived as an emotional response. The existence of these types of ESP is controversial and has not been empirically proven and indeed, concepts such as precognition violate the laws of physics which state that an effect cannot occur before its cause.  Many of the "psychic experiences" that are volunteered to parapsychologists by the general population involve apparent precognition. In one review of an American case collection, submitted to Duke University's Parapsychology Laboratory by Stokes (1997), 75% of 1777 dream-based experiences were of an ostensibly precognitive type, as were 60% of 1513 wakeful experiences. A similar pattern was identified by Drewe (2002) for a separate collection of 157 cases experienced by children - here, the largest category of experiences was again of precognitive dreams (52%), followed by precognitive intuitions (52%). A German case collection by Sanwald (1959) produced a similar figure: 52% of 1,000 cases were of the apparently precognitive type and a British study by Green (1960) of 300 volunteered cases showed 34% to be apparently precognitive. In another survey more than half of the respondents (50.4%) reported having precognitive dreams; nearly one-fourth (44.7%) reported having multiple precognitive dream experiences; and many (30.9%) are aware they are having a precognitive dream as they dream it and know that such dreams are precognitive because they are more vivid or real; they ‘feel different’ or are experienced as ‘short, precise and vivid’.

Precognition is believed to be a form of future vision – seeing into the future before it happens (either by waking visions, déjà vu or dreams, the latter being the most common type of precognitive experience). JW Dunne, a British aeronautical engineer, recorded each of his dreams as they occurred to him, identifying any correspondences between his future experiences and his recorded dreams. In 1927, he reported his findings, together with a theory, in An Experiment with Time. He concluded that at least 10% of his dreams appeared to represent some future event, pertaining to some relatively trivial incident in his own life, or some major news events appearing in the press a day or so after the dream. Dunne concluded that precognitive dreams are common occurrences - many people have them without realising it, largely because they do not recall the details of the dream. Also reported in the book was an experiment Dunne conducted with several other people who studiously recorded their dreams and sought to associate them with subsequent experiences. Dunne felt these confirmed his theory, but a 1933 independent experiment by Besterman failed to replicate his findings. With ‘free-response’ methods, experiments have been conducted by Krippner et al (1972) in precognitive dreaming at the sleep laboratory of the Maimonides Medical Center in precognitive Ganzfeld (a form of sensory deprivation situation) hallucinations and visions. While such experiments have produced some suggestive evidence for precognition, they have been somewhat limited to studies of selected participants, and have involved procedures that can be too expensive for other researchers to replicate, or too complex to theoretically interpret. Most experiments involve a ‘forced-choice’ procedure - the first such ongoing and organised research program on precognition was instituted by JB Rhine in the 1930s at Duke University's Parapsychology Laboratory. Another class of experiments has tested for precognition by unconscious signs. These have involved physiological responses, such as of skin conductance and electroencephalographic activity, or indirect psychological measures, such as ratings of preference for one or another target alternative. In these experiments, participants are not asked about their experiences, and do not need to be informed that they are participating in an experiment on ESP. Dick Bierman & Dean Radin (1997, 1999) have reported positive evidence of precognition in experiments of these kinds.

Various psychological processes have been used to explain the phenomenon of precognition:
  1. Selection/memory bias – subjects remember ‘successes’ and forget ‘failures’
  2. Unconscious perception – subjects unconsciously infer (from information that they have unconsciously learned) that a specific event is likely to occur in certain circumstances. As with cryptomnesia, when the event occurs, the former knowledge appears to have been acquired without the aid of recognised channels of information
  3. Self-fulfilling prophesy/unconscious enactment – the subject brings to pass ‘precognized’ events without conscious awareness of their own agency
In one experiment by Alcock (1981), subjects were asked to write down their dreams in a diary, preventing the selective memory effect (by which the dreams are retrospectively ‘fitted’ onto subsequent real-life events) and the dreams no longer seemed accurate about the future. Another experiment by Madey (1993) gave subjects a fake diary of a student with apparently precognitive dreams. This diary described events from the person's life, as well as some predictive dreams and some non-predictive dreams. When subjects were asked to recall the dreams they had read, they remembered more of the successful predictions than unsuccessful ones.

Precognition can be conceived as an extraordinary process of clairvoyance, involving no direct perception of the future. If, as is offered by the philosophy of determinism, all future events are determined by present conditions, then it can be suggested that it is clairvoyance of all the relevant present conditions that permits one to know their future outcomes. Alternatively, if somebody in the present is aware of what will happen in the future, then it can be suggested that it is telepathy of that information that grants oneself a like knowledge of the future. ‘Seeing into the future’ can also be conceived as not a direct perception of a future event, but only a perception of one's own future experience of that event - Rhine called ‘precognitive sensory perception’. Support to this suggestion is given by the meta-analysis which includes the study of a subset of experiments in which details were provided about the feedback of target information given to subjects in the future. The study shows that when no feedback was given, the significance of the results fell to chance-expectation. This does suggest that the contacts were being made with the subject's future experience of receiving the target information, and not with the targets themselves. The construct of psychokinesis permits another paradigm with which to consider precognition. It can be suggested that precognition involves the ‘influence’ of present conditions so that they conform with what is precognized. Alternatively, a retro-causal process can be proffered as an explanation, raising the idea that, at a future time, the ostensibly present conditions are influenced backward in time. As for theories of precognition itself, parapsychologists have offered several phenomenological theories that – like most psychological theories themselves – do not presume to provide a physical explanation of how precognition occurs, but only seek to describe the processes which are occuring. There are two classes of such theories, which are not exclusive to each other. The first is subliminal awareness, discussed separately and distinctly, by Dunne (1927) and Saltmarsh (1938). This supposes that awareness is fundamentally trans-temporal, acquiring information beyond the ‘specious present’ of information that is typically available for immediate awareness.  While we are only ever consciously aware of some limited temporal range of information, these theories assert that, unconsciously, a much wider temporal range of information is sampled and used for the benefit of the organism or subject. The second class of theory is influenced by Gerald Feinberg's concept of a tachyon (particles that travel faster than light). Some parapsychologists such as Martin Ruderfer (1974) theorised that tachyons can travel backwards in time and may be able to explain cases of precognition. The British physicist and mathematician Adrian Dobbs (1965) proposed a theory in which precognition occurs due to ‘positrons’ - hypothetical particles similar to tachyons that travel backward in time which may contact an observer's brain to produce a precognitive experience. The major problem with the tachyon theory of precognition is that tachyons have never been observed to exist; they remain theoretical constructs.

Psi-mediated instrumental response theory, offered by then psychologist Rex Stanford (1974) proposes that humans unconsciously and automatically scan their environment for motivationally relevant information, including - as the subliminal awareness models suggest - information that will only occur in the future of each conscious observer. This information will be used, by those who are so disposed, to place the person in a goal-relevant position with respect to its environment. This creates the experience of precognition, should some of this information have been represented in conscious imagery or other representational forms. One class of parapsychological theory – for example Schmidt (1984) and Walker (1984, 1987) makes reference to the measurement problem in quantum mechanics, particularly as it implicates the constructive role of human observation. Precognition, in the context of these theories, is generally conceived in the manner of retroactive psychokinesis, but without recourse to any notion of the transmission of psychophysical energy. According to some observational theories, it is at the point of observation of a future event that the event is, in fact, determined, and, under certain conditions of motivation, randomness and feedback, this future observation can inform the present observer. Another class of theories is based on the block universe model, in which future events already exist in spacetime, according to the special theory of relativity. The theories explain precognition as the retrieval of memories from the brain in the future, which could occur in a similar way to that in which ordinary memories are retrieved from the brain in the past – Marshall (1960) and Taylor (2007) for example. 

The theory proposed by Taylor is based on the work of David Bohm (1982) - the theory of the implicate order, which suggests that if similar structures are created at different places and different times, the structures resonate with a tendency to become more closely similar to one another. Taylor applies the principles to the neuronal spatiotemporal patterns that are activated in the brain, to show how an information transfer could be produced. For example, a precognition would occur when the pattern activated at the time of the future experience of an event resonates with any similar pattern that is spontaneously activated in the present. This might enable the present activation to be sustained until it produces the conscious awareness of an event similar to the one that will be experienced in the future.

Louisa Rhine at the Parapsychology Laboratory at Duke University compiled the best-known and largest body of dream evidence. Rhine (1969) collected over 7000 accounts of ESP experiences - the majority of these accounts were dream related and were seemingly precognitive in nature. The material for this work was collected by advertisements in various well-known popular media.

Ryback (1988) a psychologist in Atlanta, used a questionnaire survey approach to investigate precognitive dreaming in college students. His survey of over 433 participants showed that 290 or 66.9 percent reported some form of paranormal dream. He rejected many of these claims and reached a conclusion that 8.8 percent of the population was having actual precognitive dreams.

An early inquiry into this phenomenon was done by Aristotle in his On Divination in Sleep. His criticism of these claims appeals to the fact that ‘the sender of such dreams should be God" and "the fact that those to whom he sends them are not the best and wisest, but merely commonplace persons". Thus: "Most [so-called prophetic] dreams are, however, to be classed as mere coincidences..." Here, "coincidence" being defined by Aristotle as that which does not take "place according to a universal or general rule" and referring to things which are not of themselves by necessity causally connected. His example being taking a walk during an eclipse - neither the walk nor the eclipse being apparently causally connected and so only by ‘coincidence’ do they occur simultaneously. Other researchers in this area are more guarded in their reports on the value or use of dreams. In his book The Interpretation of Dreams (1900), Freud argued that the foundation of all dream content is the fulfillment of wishes, conscious or not and devoid of psychic content.  On the other hand, Freud's view of precognition evolved. According to Jung, Freud's ‘materialistic prejudice’ and ‘shallow positivism’ lead him to reject the entire complex of questions relating to precognition and the occult as ‘nonsensical’. But, according to Jung, years later, Freud both "recognized the seriousness of parapsychology and acknowledged the factuality of 'occult' phenomena". Dreams which appear to be precognitive may in fact be the result of the ‘Law of Large Numbers’. Robert Todd Carroll, author of The Skeptic's Dictionary explains it this way: "Say the odds are a million to one that when a person has a dream of an airplane crash, there is an airplane crash the next day. With 6 billion people having an average of 250 dream themes each per night, there should be about 1.5 million people a day who have dreams that seem clairvoyant."

The most extensive studies on precognition in dreams were carried out by the research group at the Maimonides Hospital, New York (Krippner et al, 1989). In these studies a ‘sender' attempted to send images to a ‘receiver' who slept in another room and whose sleep was recorded with standard EEG leads. When the sleeper entered REM he was awakened and reported whatever he was dreaming. Independent judges blind to the purpose and procedures of the experiment then took the dreams and judged if they contained any of the images sent by the sender. The experiments were monitored by independent observers and professional magicians to make sure that there was no possible leakage occurring between the experimenters, the sender or receiver. Subsequent analyses of hit rates yielded highly significant results. Dream images very frequently contained images sent by the sender. Further studies in other labs involved the dreamer attempting to dream about a target that would be randomly selected once he awoke. Once again hit rates were far beyond chance levels. Despite these exciting results some labs have failed to replicate the highly significant hit rates while other Labs have replicated the basic findings. Differences in replication may be due to many factors. Psi may not exist at all. Or it may be that you are much more likely to get significant hit rates if you use participants with high Psi abilities like the high stimulus seekers in the work of Bem (2011).

Wednesday 21 November 2012

Dream Bites #3

One disputed fact about dreaming (because it is currently empirically unprovable) is that we can only ever dream of what we know and have experienced. Dreams of unfamiliar strangers who play out roles are not creations of the imagination, but the real faces of the hundreds of thousands of actual people we have seen in our lifetime, whether we remember them or not. Our brains are therefore loaded with an endless supply of dream characters and other imagery (or other forms of sensory experience – such as sounds, touch, smell etc) which we collect over the course of our lives. Sometimes, our dreaming mind may use several different faces/sensory memories to create a composite image/symbol – for example, combining aspects or characteristics of more than one person/thing to form something entirely new and unique. But it’s still dream content based on things known and experienced by the dreamer. 

Dream Bites #2

In the 1950s, a ‘popular’ idea emerging from dream research stated that everyone dreams in black and white, but remember in colour – mentally painting the picture in waking memory. In 1951 Calvin Hall proposed that only 29% of dreams occurred in ‘technicolour’ whilst Tapia et al (1958) believed the percentage of colourful dreams to be considerably lower – approximately 9%. However, more recent research suggests that humans are able to dream in both colour and black and white (approximately 12% of persons with normal sight report their dreams occur in black and white, with only 4.4% of dreams being reported as black and white by under 25-year-olds), although the vast majority of people report dreaming in colour. Research from the American Psychological Association suggests that elderly persons dream in black and white because they grew up in the era of black and white television or because their dreams – reflecting their contemporary waking experiences and concerns – are less emotionally charged or stimulating than those of their younger counterparts. When moments of unexpected heightened emotion return, it may be that dreams reflecting these moods are once again experienced in vivid colour. 

Why do we forget our dreams?



Dream research indicates that many people may dream 4 -6 times per night (Scientific American (2011) states we dream on average, 5 times per night, working out to approximately 1, 852 dreams per year) – some people remember all their dreams, whilst others recall none at all and believe they ‘don’t dream’. Dream worker, Jeremy Taylor of the Marin Institute of Projective Dream Work suggests that because dreams are often complex, unusual and distinctly different from our real-life experiences they may be difficult to comprehend and express in thought and language. They may also be multi-layered and conceptually abstract – a state Taylor describes as being “not yet speech-ripe”. Dream recall may also be affected by disinterest in the dreaming process (it is common to find dream recall improves simply by taking an interest in dreaming or actively encouraging yourself – using various methods described in this Blog – to remember dreams upon waking); alcohol or drug consumption; stress or exhaustion; moon phases and biorhythms; traumatic events; or inability/unwillingness to wake up at the time of dreaming. 

Content-based Theories
Other ‘content-based’ theories of dreaming have attempted to explain ‘sleep amnesia’ – for example Salience Theory, which states that we may forget dreams simply because they are meaningless and have no application in waking life. L Strumpell, a theorist working in Freud’s day, posited that dreams are forgotten because dream content is not organised in a comprehendible manner. In Ellman & Antrobus, The Mind in Sleep: Psychology and Psychophysiology (1991), the authors suggest that dream kinesthesia may be responsible for forgetting dreams – when we wake, our physical movements cause us to ’lose’ the dream. Another possibility is that our memories are formed through repetition and finding connections to other parts of our lives. So when dreams are especially unique or too undefined to be relatable, it’s harder to tie them to real-life events and remember them. 

Interference Theory
As with all aspects of dreaming, there is no definitive scientific explanation as to why some dreams are forgotten. One study published in Journal of Clinical Psychology (2006), conducted by the Southern Illinois University at Carbondale tested Freud’s theory of repression against Interference Theory (dream kinesthesia falls under this theoretical approach to dreaming) and found preference for the latter explanation, although it is impossible to isolate a single factor responsible for sleep amnesia. In 2009, Scientific American published a study by Christof Koch entitled ‘A ‘Complex’ Study of Consciousness’ which explored that happens to the mind during sleep. Koch pointed out the incongruity between the brain’s high levels of activity during REM sleep and our inability to recall dreams upon waking, plus the fact that nerve operation does not differ much during this stage as from periods of ‘quiet wakefulness’. He suggests that the brain waves which occur during REM sleep may be the cause of sleep amnesia, preventing us from remembering dream content. Natalie Angler, a scientific journalist for the New York Times states that 75% of dreams recalled in dream laboratories and dream journaling, recall negative dream content – supporting theories which suggest that our dreams are a way of working though troubling thoughts or emotions. According to current science, clarity of dreams depends on neurochemical conditions in the brain.  Dreams are forgotten due to deficiencies in the hormone norepinephrine in the cerebral cortex, and more generally, due to the fact that dreams are not highly conscious activities in the brain and thus are not consolidated as a memory.

Earnest Hartmann, professor at the Psychiatry department of Tufts University School of Medicine and director of the Sleep Disorders Center at Newton-Wellesley Hospital, states that forgetting dreams is usually attributed to neurochemical conditions of the brain during REM sleep – the most compelling evidence being an absence of the hormone norepinephrine in the cerebral cortex – an area of the brain with functions in language, memory, consciousness and thought. A 2002 study published in the American Journal of Psychiatry supports the theory that a presence of noreprinephrine in humans enhances memory, although its role in learning and recall is unclear. However, a lack of norepinephrine does not fully explain why we forget dreams so easily. Recent research suggests that dreaming exists on a continuum of mental activity and functioning – focused concentration is on one end of this spectrum, whilst dreaming and mind-wandering is at the other. Dreaming – whether ‘day dreaming’ or during REM sleep – is a less consciously directed form of thought and therefore it is not easy to remember – because we are good at forgetting non-essential, non-relevant details and tend to remember things of emotional significance. Mulling over important thoughts activates our dorsolateral prefrontal cortex (DLPFC), a brain region that facilitates memory. Although most dreams vanish, certain ones tend to remain. These dreams were so beautiful/anxiety-provoking or bizarre, they captured our attention and increased activity in our DLPFC. Thus, the more impressive your dream or thought, the more likely you are to remember it.

It may be that dreams are not encoded into our memory, because they are unrehearsed, unpredictable – and simply because we fail to pay attention to them. When we are awake and want to remember something, we make a conscious effort to remember it – to subscribe it to memory so it can be effectively recalled and acted upon at an appropriate time. It is well known – and documented on this Blog – that the best way to recall your dreams is to make a conscious decision to remember them and give yourself a ‘reason’ to recall – i.e. for the purposes of recording or interpreting them. Studies of dream recall – using subjects who rarely recall a dream (less than one per month) and those who routinely recall the majority of their dreams (several per night) found that the biggest difference between the groups was the motivation to pay attention to, and recall, dreams. The people who best recalled their dreams were people who had decided that their dreams were worth remembering. 

Memory Consolidation Theory
Memory Consolidation Theory states that blocking REM sleep impairs the ability to perform procedural tasks - tasks that involve the learning of a skill through a sequence of steps that involve making predictions. For example, rats trying to find their way around a complex maze to get a reward remember much better how to do the task if they have had REM sleep. Without REM sleep, the knowledge becomes damaged. So REM sleep would seem to facilitate this type of learning. It has also been shown that, in complex learning, memory is improved if we have both slow-wave sleep and REM sleep, otherwise the knowledge doesn't seem to survive quite so well. So, clearly, there is some connection between memory and REM sleep. But is there evidence that the REM state and dreaming exist fundamentally to carry out memory consolidation? The first piece of evidence that goes against this possibility is that taking MAOIs, the antidepressants that suppress REM sleep, does not lead to memory impairment. So, although there is some evidence that certain types of learning do seem to be improved by REM sleep, most dreaming cannot be about retaining new learning experiences, according to Griffin and Tyrell (2006).

The second fact that goes strongly against the memory consolidation hypothesis is that many people fail to remember their dreams! It is very rare to vividly remember all dreams, unless you've trained yourself to do so, despite the fact that we dream for about two hours a night. Dream researcher Allan Hobson, an expert trained to recall his dreams, has himself pointed out the fact that, when he looked at the number of dreams he had recorded against the number he had forgotten, it was something like 0.0002%. So it seems hard to see how we could be dreaming to make our memories permanent if we forget the material we are processing as soon as we open our eyes (yet, as certain types of memory do seem to be facilitated by REM sleep, any state-of-the-art theory of dreaming must be able to account for it).

Activation Synthesis Theory
Hobson and McCarley proposed the Activation Synthesis Theory.  Laboratory studies of brain waves show that, just before we go into REM sleep and during it, powerful electrical signals pass through the brain like a wave. On electroencephalogram recordings (EEGs), they appear as sudden spikes. The signals arise from the pons (P) in the brainstem, from the neurons that move the eyes, and then travel up via a part of the midbrain called the geniculate body (G) to the occipital (O) cortex in the higher brain - so are known as PGO spikes (they also constitute what is termed our orientation response, which, when we are awake, is what directs our attention to any sudden change in the environment, such as a sound or movement). Hobson and McCarley's theory was that these PGO spikes were sending a random ‘barrage’ of stimulation through the brain every so often, activating the whole cortex as a result; the higher brain had to try and make some sense of this random barrage, and dreams were the result. Dreams, therefore, were an epiphenomenon: they had no intrinsic meaning. They were just the brain's efforts to synthesise some sense from random signals. Evidence has accumulated over the last 30 years to disprove this theory. The first piece of evidence that disproved it emerged once PET scanning of the brain was developed. According to Hobson and McCarley's original theory, a barrage of random stimulation coming up periodically from the brainstem was synthesised by the prefrontal cortex into dreams, but scans of the brain in the REM state showed that the cortex was very selectively activated. The emotional brain (the limbic system) and the visual brain were highly activated but the prefrontal cortex was excluded from this stimulation (the very part supposed to be doing the synthesising). Indeed, Hobson himself, over the last few years, has been so drastically redrafting the theory that it is just a pale shadow of its original presentation.  Even he now agrees with the evidence that (instead of global forebrain activation being responsible for dream synthesis) it is the emotional ‘brain’ which is responsible for dream plot formation. This evidence on its own disproves the theory. However, there is more. Research accumulated over the last 40 years (and universally accepted by dream researchers) shows that dreams are coherent and that they typically relate to previous waking experiences and memories. There also tends to be continuity in the type of dream content over time and this could not be so if there were a random stimulus. Hobson and McCarley also theorised that REM sleep serves to 'rest' the cells in the brainstem which produce serotonin and noradrenalin, because in REM sleep these particular neurotransmitters are not used by the brain. Their idea was that these neuronal pathways were being rested so that we would wake up the next day, refreshed by REM sleep. Consequently, then, the more REM sleep people had, the more refreshed they should be. But researchers looking at the sleep patterns of depressed patients found that they had massive amounts of REM sleep in proportion to slow-wave sleep and yet, far from waking up refreshed, they were waking up exhausted! How did Hobson account for this? He just said: "It is a paradox". 

Yet another problem with this theory, which Hobson now admits, is that it can't explain why certain dreams have positive emotions and some have negative emotions. But the final nail in the coffin for the Activation Synthesis Theory's is the finding that deep brainstem lesions do not generally stop dreaming, whereas certain lesions in the cortex do, despite the existence of brainstem-initiated REM sleep.

Freudian Theory
Freud’s theory asserts that we forget our dreams due to repression or self-preservation. As, under Freudian theory, dreams are a form of subconscious wish-fulfillment, we forget certain dreams as a result of our minds ‘blocking’ material – wishes, desires and fears – that we are unable or emotionally ill-equipped to handle. The dream content may be too traumatic to remember. There has recently been strong evidence to show that REM involves the ‘expectation dopamine pathway’. Professor Mark Solms, Chair in Neuropsychology at the University of Cape Town in South Africa, has been pre-eminent in synthesising this research, showing that when people go into the REM state, the motivation circuit in the brain - the expectation pathway - is activated. As Freud talked about motivation and emotion, this lends some support to Freudian theories of dream analysis. But what it leaves out of the picture is that, when you activate the expectation pathway, you are activating consciousness, not necessarily some subconscious conflict. So it is also possible to argue that is no real evidence there in support of Freud. Secondly, Freud's theory has real difficulties explaining why people so often have anxiety or aggression dreams. Freud said dreams were for fulfilling wishes - but who would want nightmares? Who would want to get beaten up or sexually assaulted in their dreams? Freud claimed that we dream to protect sleep, to prevent us being awakened by threatening, subconscious wishes. However, the REM state, in which most dreams occur, is a regularly occurring biological programme in humans and other mammals, and not something which arises to protect sleep. To recap, expectation pathways activate conscious, not subconscious, experience. There is no evidence at all that dreams are sexually motivated and Freud can't plausibly explain why we would wish for anxiety dreams. The REM state occurs in all mammals, so it is not just a human activity, protecting sleep, as Freud suggested. According to Griffin and Tyrell (2006) of the Human Givens Institute, a cat is unlikely to be dreaming about its Oedipus complex, so the attempt to revive Freud's theory seems to be based more on wishful thinking than on realistic considerations of its defects. So, according to the research of Griffin and Tyrell, Freud's theory just doesn’t explain in any coherent fashion the fact that dreams involve far more than wishes and that only a minority of them can actually be characterised as wishes; further his claim that all dreams are sexually motivated is no longer given any credence. I would argue that Freud’s theory is based on the notion that dream content undergoes symbolic transformation  and consists of both manifest and latent content – hence the need for ‘dream work’ to unlock the symbolic meaning of the dream material which may not appear comprehensible or relevant to real-life on the surface. Aggression, sex or anxiety-provoking dream symbolism may be interpreted in a way which unveils subconscious desires and drives. Griffin and Tyrell neglect to mention that subconscious wishes and desires may well cause anxiety or involve forms of violence or taboo sexuality – indeed, under Freudian theory, this is all the more likely – the very function of dreaming, according to The Interpretation of Dreams (1900) was to work through unacceptable or harmful thoughts, wishes and desires which the waking mind was emotionally unable to process or indulge. They also fail to note that humans experience far more complex emotions and thought processes than other mammals – something which may be reflected in dream content and function. 

Parasitical Connections Theory
Crick and Mitchison's Parasitical Connections Theory suggests that we dream to forget. Their idea came from studying work done on computer programmes that simulated neural intelligence. An overload of incoming information could trigger ‘parasitical connections’ between unrelated bits of information that interfered with memory, and an unlearning system had to be developed to knock these out of the computer systems. Crick and Mitchison postulated that a complex associational network, such as the cortex, might become overloaded in the same way, and that the PGO spikes were an unlearning mechanism, in the form of random 'bangs' coming up from the brainstem every so often, to knock out these fairly weak parasitical neural links. As, at that time, most dreams were thought to be bizarre in content, this was taken as evidence for the existence of these parasitical connections. Crick and Mitchison theorised that, if we didn't have dreaming, we would go on making more and more bizarre connections, which would imply that, if we block REM sleep, our memories should become more addled. If this theory is correct, then depressed people on antidepressants that block REM sleep (monoamine oxidase inhibitors - MAOIs) should suffer memory impairment they don't. If anything, depressed people on MAOIs report memory improvement rather than increased confusion in memory recall.Yet another problem with the theory is that, over the last decade or so, there have been significant technical advances in the recording of what actually happens during dreaming. The overwhelming majority of dreams are, in fact, quite routine, everyday experiences; it is the tiny percentage of dreams that we recall that seem bizarre: dreams recorded in the sleep laboratory, when sleepers are woken as soon as they go into REM sleep, are mostly not bizarre at all. As a result of this discovery, Crick revised his theory to suggest that it might still, at least, explain those few dreams that do have a bizarre component to them. In other words, his theory has been so drastically modified that very little of it remains at all. Finally, since Crick and Mitchison formulated this theory, not a shred of evidence has arisen to show that the human brain makes parasitical connections - that is something known only to occur with computer networks.

Expectation Fulfillment Theory
Evolutionary theory argues that animal brains – including humans – have evolved in ways which best help predict effective survival instincts and behaviours. The evolution of the cortex in mammals led to an increase in the processing capacity of the brain – instead of acting solely on instinctual impulses, the animal is able to weigh up the benefits and risks of a particular activity. In more technical terms, it enabled the ancient dopamine prediction circuits of the limbic system to be subjected to a higher order risk analysis, based on the additional computing power provided by the evolved cortex. However, that left another problem to be solved - the limbic system communicates with the cortex via behavioural impulses (emotions). If these are not acted upon (for instance, because the strategy is deemed too risky or because the cortex has set other priorities or motives — such as deciding, in certain circumstances, that it is more important to protect young than to chase a possible food source) they don't go away. In the case of humans, this state of unfulfilled expectation can also occur when we think about something in the future or the past that causes emotional arousal in the present, but which can't - by its very nature - be acted upon. These uncompleted emotional impulses or ‘expectations’ stay switched on, taking up processing capacity in the expectation system. So far, two distinct strategies have evolved for dealing with this biological conundrum. Firstly – found in the spiny anteater - is the development of a much bigger cortex to store all these expectations whilst retaining sufficient spare computing power for making new, ongoing risk assessments. This may also be the strategy evolved by dolphins, which have an exceptionally large cortex. The muscle paralysis that accompanies REM sleep places dolphins at risk of drowning, so they can have hardly any REM sleep. The second and much more efficient method is dreaming. Whilst dreaming, we act out the unrealised expectations from waking by pattern matching them to analogous sensory patterns — images and events stored in memory — as it is through pattern matching that the REM system works. An expectation is an imagined scenario, using images from memory. This accords with Freud’s theory of dreams as wish-fulfillment. In dreaming, we are asking memory to provide a scenario that matches a scenario that is already a part of memory — the event that aroused the expectation. So the matching scenario has to be the best fit that memory can provide. Think of it this way — if you left hand and ask your brain for a best-fit pattern match, it can't use your left hand because that is the one you want a match for — so it must use your right hand, as the best-fit pattern match for your left. This does not happen in waking because we pattern match our expectations to whatever stimulates them in the environment, not to a memory. If you want an ice cream, the expectation is fulfilled when you are actually eating it. The dream, then, by fulfilling the expectation, completes the circuit and switches off the arousal. But that is not the end of the matter, for we have now converted an unrealised expectation into a factual memory of completing it. Ordinarily, the hippocampus (the conscious memory store) archives our memories of recent events and quickly deconstructs those memories, sending them to various parts of the cortex — the parts concerned with vision, hearing, touch etc — for storage, in order to facilitate efficient pattern matching. But, if the dream is allowed to be stored as a real memory, it will corrupt the memory store and greatly diminish our ability reliably to predict the outcome of similar experiences in the future. This is avoided by preventing the hippocampus from sending the dream information to the cortex for long-term storage (see Busáki (1995), ‘The hippocampo-neurocortical dialogue’, Cerebral Cortex 6, pp. 81—92). As explained earlier, PET scans and other types of research have shown that, during the dreaming process, the prefrontal cortex is closed down. So it is no accident that the prefrontal cortex is switched off during dreaming; or that the hippocampus doesn't de-construct information and send it all around the brain - because what the hippocampus is doing in dreaming is getting rid of expectations that didn't pan out while we were awake. It is getting them out of the way and making them inaccessible, in effect, so as to allow us to build up a proper, intelligence prediction and expectation system and an accurate storage of knowledge (this also explains the evidence for memory consolidation — if you take away all the false expectations, the memories that are consolidated are more accurate). The Expectation Fulfillment Theory can therefore explain why dreams are about stimulating or provocative events, particularly about emotionally arousing expectations and why dreams may be consistent over time, in addition to the developmental aspects of dreaming. It can explain the other tests conducted and published by Bill Domhoff, but more than that, it explains the cutting-edge evidence that the brain is ever malleable, by explaining how it can be so malleable. It was Abraham Maslow who introduced the idea that, until basic needs are met, people can't engage with questions of meaning and spirituality - what he calls self-actualisation. Another contributor was William Glasser, who put forward the idea that fulfilment of people's needs for control, power, achievement and intimacy depends on their ability to behave responsibly and conscientiously - he argued vehemently that mental illness springs from these needs not being met.

The purpose of the brain is to predict, so that we can get our needs met. We need to have a system that can continually adapt itself, and the Expectation Fulfilment Theory shows how the brain does that by cancelling out the expectations that didn't work. It enables us to have a contemporary register of what really does get needs met in our lives, so that we can more accurately predict what we need to do in the future (but we can only work with the experiences we have had - if, as a child, a woman experienced both abuse and love from her father, she may continually seek a relationship with abusive men, until eventually she can learn that love exists separately from abuse, for example). It may well be questioned then, whether by recalling our dreams, as sometimes happens, we are simply ‘undoing’ the dream work. The answer is no - because the arousal is switched off once the expectation is acted out. When we are awake, the cortex is switched on, enabling us to compare dream content to what is really happening around us and, thus, to distinguish between dream and reality. Occasionally the cortex is alerted by some incongruity in the dream experience - such as flying - and we become aware that we are dreaming (lucid dreaming) But, according to some dream theorists, this risks undoing the dream work of deactivating the experiences — because we now know we are experiencing a fantasy (in more primitive mammals, if an altering of the cortex were to happen, it is less likely their brains could make the distinction between dream and reality; the fantasy would be treated as real and would therefore corrupt the memory stores). 

Scientists have long known that memories are formed in the brain's hippocampus, but are stored elsewhere - most likely in the neocortex, the outer layer of the brain. Transferring memories from one part of the brain to the other requires changing the strength of the connections between neurons and is thought to depend on the precise timing of the firing of brain cells.

"We know that if neuron A in the hippocampus fires consistently right before neuron B in the neocortex, and if there is a connection from A to B, then that connection will be strengthened… And so we wanted to understand the timing relationships between neurons in the hippocampus and the prefrontal cortex, which is the front portion of the neocortex” explains Casimir Wierzynski, a Caltech graduate student in computation and neural systems and co-author of the study “State-dependent spike timing relationships between hippocampal and prefrontal circuits during sleep” (2009) Neuron. The research team - led by Athanassios Siapas, a Bren Scholar in the Caltech Division of Biology and an associate professor of computation and neural systems - used high-tech recording and computational techniques to listen in on the firing of neurons in the brains of rats. These techniques helped them pinpoint a number of neuron pairs that had precisely the kind of synchronous relationship they were looking for - one in which a hippocampal neuron's firing was followed within milliseconds by the firing of a neuron in the prefrontal cortex. "This is exactly the kind of relationship that would be needed for the hippocampus to effect changes in the neocortex - such as the consolidation, or laying down, of memories" states Wierzynski.

Once these spike-timing relationships between the hippocampal and prefrontal cortex neurons had been established, the team used their high-tech eavesdropping techniques to hear what goes on in the brains of sleeping rats - since sleep, as Siapas points out, has long been thought to be the optimal time for the memory consolidation. As it turns out, those thoughts were right - but only part of the time.The team did indeed hear ‘bursts’ of neuronal chatter during sleep - but only during a phase of sleep known as slow-wave sleep (SWS), the deep, dreamless periods of sleep. "It turns out that during slow-wave sleep there are these episodes where a lot of the cells in the hippocampus will all fire very close to the same time" says Wierzynski. In response, some cells in the prefrontal cortex will fire in near unison as well, just milliseconds later. "What's interesting is that the bulk of the precise spike timing happens during these bursts, and not outside of these bursts," he adds.

On the other hand, during rapid-eye-movement (REM) sleep, the previously chatty neuron pairs seemed to talk right past each other, firing at the same rates as before but no longer in concert. “It was surprising" says Wierzynski, "to find that the timing relationship almost completely went away during REM sleep."
Since REM sleep is the phase during which dreaming occurs, the scientists speculate that this absence of memory-consolidating chatter may eventually help to explain why dreams can be so difficult to remember. As intriguing as that idea may be, the researchers caution that these findings only raise possibilities, providing avenues for further research in the field. Siapas asserts "now that we've shown this link, we have a framework we can use to study these questions further. This is just a step toward our goal of some day fully understanding the relationship between memory and sleep."

Writing in Behavioural and Brain Sciences, in a special issue devoted to the most widely promoted dream theories, Professor Domhoff of the University of California, recognised as one of the leading researchers in this field, commented on the evidence presented, concluding "if the methodologically most sound descriptive empirical findings (i.e. the findings that are most solidly established to explain dreaming) were to be used as a starting point for future dream theorising, the picture would look like this: 

  1. Dreaming is a cognitive achievement that develops throughout childhood 
  2. There is a forebrain network for dream generation that is most often triggered by brainstem activation (the PGO spikes)
  3. Much of dream content is coherent, consistent over time and continuous with past or present emotional concerns"

So any theory of dreaming would have to account for those three most solidly established findings (also perhaps including the need to explain memory consolidation as well, if a theory were to explain the full picture).

Domhoff's final conclusion is that "none of the papers reviewed in this commentary puts forward a theory that encompasses all three of these well-grounded conclusions. This suggests the need for a new neurocognitive theory of dreaming”. In other words, according to Domhoff, theories that have dominated the field over the last 30 years do not explain why we dream, and there is need for a completely new one.
Griffin and Tyrell argue that the Expectation Fulfillment Theory is an adequate explanation for this phenomenon of dreaming, as it is rooted firmly in biological science, yet also recognises the rich, subjective experience of dreaming in the individual. It states that all arousals of the autonomic nervous system - the generation of an emotion, however slight - form half of a process. The second half of the process involves the brain ‘fulfilling’ the expectation (an emotion is the same as an expectation) through an action of some kind. If that doesn't happen in reality during the daytime, it happens metaphorically in a dream at night, thus completing the arousal - de-arousal process. Recurrent dream themes tend to reflect unfulfilled expectations and daily concerns, which may not be those acknowledged by the wakeful individual as being the most significant ‘concerns’. The theory also explains Domhoff’s developmental theory – dreams are consistent and coherent (representing metaphorical symbols of expectation fulfillment) and become more complex over time (as we mature we develop more complex modes of introspection and abstract thought). It also apparently explains the relationship of REM function in foetuses with that adulthood – the pattern-matching templates are programmed whilst in the womb and throughout early life – the same pattern-matching process which is used in dreams to deactivate emotional arousal. The theory is also consistent with Domhoff’s notion of a ‘forebrain network for dream generation’ which is triggered by brainstem activation and the idea that dream is consistent and relates to waking experiences and concerns. For example, persons suffering from depression may have too much REM sleep due to an increase in introspection and waking anxieties and concerns. This causes so much arousal which needs to be de-aroused/discharged during sleep that individuals often awake exhausted, rather than refreshed, due to lack of deep, dreamless delta-wave sleep. A second piece of evidence arises from an analysis of Freud and Jung's specimen dreams, which they had offered as the best convincing evidence for their respective theories. The analysis revealed that the dreams were perfect metaphorical manifestations of what was worrying them the day before - according to detailed written data they had themselves provided, and this was structurally extremely tight-fitting data. Freud's dream of Irma's injection (which I have written about elsewhere in this Blog) and the expectations/desires he had the previous day; the sequencing of the dream; the characters involved; and what they actually did in the dream provided an exact mirror image of the biggest event he had on his mind before he went to bed that night – the medical condition of a female patient and fear of accusations of negligence. There is no ambiguity there and it was likewise for Jung's dream, which I shall write about in the near future.

REM sleep has three functions: to switch off expectation and reduce the stress of managing increasing numbers of expectations which may have no relevant to the current situation; it creates space storage capacity in the cortex; and it preserves the integrity of our emotional templates.

The brain has ‘adaptive intelligence’ – starting off with basic instincts which can be modified as a result of experience, enabling the brain to continually refine its learning processes. In the Expectation Fulfillment Theory, patterns are ‘programmed’ into the brain when in REM states – during gestation or early childhood, which humans seek to complete in the environment after birth.  All learning is thought to be a form of pattern-refinement. The first evidence for this came from research findings that the honeybee has a neural transmitter called octopamine, which is similar to dopamine (the human motivation neuro-chemical). One single cell, using this neuro-chemical, motivates the bee to go out every morning to search for nectar (instinctive behaviour) and then that cell keeps a record of where the nectar is found. The next time the bee goes out, it predicts (on the basis of that record) where it will find nectar today. So, if the bee got nectar from a blue flower yesterday, it will pattern-match and go to a blue flower today, predicting and expecting that it will find nectar there again. If it doesn't get nectar from the blue flower today, it immediately revises its memory store. So the memory store will now show that blue is not such a good predictor of nectar after all. Clearly, then, the bee has an instinct plus a capability for learning; it takes an instinctive pattern, builds on current information and modifies it. That is also what was postulated by computer scientists trying to model how the brain works. Their computer program succeeded in modelling complex bee foraging behaviour, and other kinds of more complex behaviours, using this simple idea that you start with an instinctive core that can be modified through feedback from previous efforts. It is a far more efficient system for acquiring knowledge than the one suggested in the module theory - if we had masses of modules in the brain, all occupying their own areas, the brain should be pretty well fixed, and that is exactly what the evolutionary psychologists thought was so. Their idea was that those multiple modules had evolved over the two million years that we were Stone Age hunter-gatherers and that (as all of our knowledge would go back to those times) we are maladapted for the world we live in today — a very fatalistic view of human nature. But the new information allows us to be more optimistic about human capacity. Behaviour has been shown to be so very much more malleable than anyone had ever suspected.

The second source of evidence in support of the theory comes from neurological research – brain scans which show mental activity during the learning process. For example, when people are born blind, the brain cells that would have been used to generate sight learn to read Braille instead and thus, neurons are incredibly adaptive and able to take on new tasks. 

Another example, is research which shows that the hippocampal area in taxi drivers' brains grows new cells and expands when they do 'the knowledge' - the huge number of street maps they must plot out, learn and keep in their memory.

The Expectation Fulfillment Theory also explains the fundamental question of why we forget our dreams. In mammals, the ancient dopamine prediction circuits of the limbic system evolved, becoming subject to a higher order risk/benefit analysis, based on greater computing power of the developed cortex. However, the limbic system communicates with the cortex via behavioural impulses (emotions) and if these are not acted upon – because they are deemed too risky, or because there is another more pressing motive – they do not vanish, at least not in humans. This ‘unfulfilled expectation’ can also occur when we think about something (past of future) which cannot be acted upon in the present. As aforementioned, these unexhausted expectations remain, taking up capacity in the ‘expectation system’. A dream recreates a scenario which matches one which is already stored in the memory – i.e. the event which aroused the expectation – and therefore the dream content (from memory) is the best-fit the brain can provide, and completes the ‘circuit’ by switching off the arousal. We have now converted an unrealised expectation into a factual memory of fulfilling it. Ordinarily, the hippocampus (the conscious memory store) holds our memories of recent events and quickly deconstructs those memories, sending them to various parts of the cortex - the parts concerned with vision, hearing, touch, etc - for storage. It does this to facilitate efficient pattern matching - but, if the dream is allowed to be stored as a real memory, it will corrupt the memory store and greatly diminish our ability reliably to predict the outcome of similar experiences in the future. This is avoided by preventing the hippocampus from sending the dream information to the cortex for long-term storage. PET scans and other types of research have shown that in dreaming, the prefrontal cortex is purposefully switched off. 

Therefore, it is no accident that the hippocampus doesn't deconstruct information and send it all around the brain, because what the hippocampus is doing in dreaming, is getting rid of expectations that didn't pan out while we were awake. It is getting them out of the way, making them inaccessible in effect, so as to allow us to build up a proper, intelligence prediction and expectation system and an accurate storage of knowledge. This also explains the evidence for memory consolidation - if you take away all the false expectations, the memories that are consolidated are more accurate. The Expectation Fulfillment Theory can therefore explain why dreams are about emotionally arousing events, particularly about emotionally arousing expectations; and why dreams are consistent over time. It explains the developmental aspects of dreaming; and the other tests put down by Domhoff. But, more than that, it explains the cutting-edge evidence that the brain is ever malleable, by explaining how it can be so malleable. 

Griffin and Tyrell explain why it is necessary to forget dreams by furthering the model and suggesting the 3-E approach: the Elimination of Emotional Expectation Theory. Elimination of emotional expectation lowers emotional arousal and frees up spare capacity in the cortex. ‘Dream amnesia’ eliminates failed expectations, thus updating the expectation memory stores which functions as an internal survival guide. They propose that this is the function of dreaming in the REM state. With regard to remembered dreams – this does not inhibit the function of dreaming within this model – as arousal is deactivated once the expectation is fulfilled and eliminated by pattern-matching within the dream content. The expectation has been acted out. When we are awake, the cortex is switched back on and we are able to compare dream content to our real-life environment and thus distinguish memories of dreams and reality.