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Dreams Dr Magda Osman Room 2.25 Office hours Mondays.

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1 Dreams Dr Magda Osman Room 2.25 Office hours Mondays

2 What is the function of dreams? A. Help with emotional regulation B. Play out our unconscious desires C. Reveal important aspects of our personality D. Predict the future (i.e. premonitions) E. Basic biological products of our brain working during sleep F. None of the above

3 Do dreams only occur during REM? A. Yes B. No C. Don’t know

4 Learning outcomes  Understand the complexities around the association between REM and dream states  Have an understanding of the different theoretical positions regarding the function of dreams  Have an understanding of the different methodological approaches to studying dreams (e.g. literature, diaries, self-reports, fmri)

5 What is a dream?  Sleep mentation Mental and emotional processes that occur during sleep, including thoughts, imagery, and problem- solving. Dream Properties  Mental Imagery  Temporal progression of events  Narrative coherence

6 Dream Phenomenology I  Hypnagogic State (Mavromatis, 1983) Implies different levels of consciousness – transitional states from wakefulness to sleep, sleep to wakefulness Characterized by stasis Multi-sensory  vivid imagery, auditory, visual hallucinations  NREM Sleep 10-40% report dreams when woken up static images or isolated thoughts  REM Sleep 70-80% report dreams when woken during this stage of sleep Under this state the images usually form a narrative

7 Dream Phenomenology I  Originally Dement and Kleitman (1957) first to report dream recall rates of about 80% after awakenings from REM sleep and only 7% from awakenings from NREM sleep  However, Mental activity occurs through all stages of sleep (Foulkes & Schmidt, 1983) There is no relationship between eye movements during REM and the visual imagery in dreaming.  This was demonstrated in studies showing that congenitally blind subjects also show REM, and that they also show dissociations – they have visual imagery dreams but unaccompanied by REM. (Koulack, 1972)  However some suggest that there is a relationship (Leclair- Visonneau et al, 2010)

8 How do we study dreams?

9 Methods of studying dreams  All measures are indirect Free recall EEG Disruption to sleep patterns i.e. study the effects of anti- psychotic drugs that disrupt NREM and measure the effects on cognitive functioning  Sources of data Literature – look to stories of reported dreams Survey Laboratory experiment in Sleep Laboratories Patient reports of dreams/disruption to dreaming

10 Methodology: Dream surveys  Dream surveys Hall & Van de Castle (1966)  Dreams (5 dreams per person, yielding two samples of 500 dreams each) from 100 men and 100 women (college students) were recorded.  The results from that study make up "The Norms" which are used to taxonomize the content of dreams to date.

11 Hall & Van de Castle (1966) Content Analysis

12 Methodology: Patient studies  Calvin Hall (1966) conduced a systematic study of dream reports of schizophrenic patients. In general there were differences in the content of the dreams when compared to non-clinical populations.  Fewer people in the dreams of schizophrenics, and lack of friendliness and ambition (striving for success, avoiding failure)

13 Methodology: Patient studies  Many problems with free recall studies conducted in patient and non-patient studies Highly selected circumstances (i.e. may not recall accurately the dream content) Recall rarely taken just after the dream has occurred, usually the reports are provided days later. Recall may not be free recall, some times prompts are provided which my distort the reports  (particularly in patient studies)

14 General Characteristics of REM Dreams I  Visual imagery All dreams reported include visual imagery  Most were reported to be in colour  Congenitally blind (from birth or early childhood blindness) do have dreams with visual imagery – at least recent studies suggest that they are able to draw and describe the content of their dreams which reveal details comparable to sighted participants (Bertolo et al, 2003)  Most dreams include some form of verbal details  Lucid dreams often occur during REM – but can also occur during NREM

15 General Characteristics of REM Dreams II  Patient studies Several studies report that depressed individuals recall fewer or less detailed dreams than healthy controls (e.g., Barrett & Loeffler, 1992) In bipolar disorder a shift to depression is also associated with a decrease in overall number of dreams reported (e.g., Beauchemin & Hays, 1995) During depressed states the content of dreams reflects mood – with increased negative content as compared to non-depressed participants, and during manic states the content of dreams is of bizarre and improbable themes (Barrett & Loeffler, 1992) These studies suggest that dreams may be mood dependent

16 What do lucid dreams imply regarding the brain/mind problem? A. That our mind can control our brain B. That consciousness is separate from the brain C. That there are multiple levels of consciousness D. Don’t know

17 General Characteristics of REM Dreams III  Memory research suggest: dream sources as well as content, appear similar in REM and NREM mentation (Cavallero, Foulkes & Hollifield, 1990) the same cognitive systems produce mental activity irrespective of REM sleep stage, (first proposed by Foulkes & Schmidt, 1983) daydreaming and sleep onset dreaming are similar for content of imagery/stories. Cognitive processes involved in the creation of original narrative sequences are similar in sleep and waking. Cicogna, Cavallero & Bosinelli (1991) Ultimately, since stage REM is neither necessary nor sufficient for dreaming, one must exercise caution in interpreting studies where the two are assumed to be synonymous. (Palagini & Rosenlicht, 2011)

18 General Characteristics of REM Dreams IV  Dream Content Most dreams do not have bizarre content (1 in 8 report bizarre fantastical dreams) Most dreams are credible Emotionality is not common in dreams  Dreams with emotional content were usually unpleasant emotions Are bad dreams the same as nightmares?

19 Disturbing dreams (DDs) I Epideminological (public health research) studies show that 85% of adults report experiencing 1 nightmare within a year, and 2-6% report weekly experiences of nightmares. Propose that Bad dreams and nightmares are generated by the same processes, -  People differ in their effectiveness in regulating negative affect – affective load E.g. DDs are commonly associated with Post traumatic stress disorder, exposures to trauma (Mellman, et al, 1995; Woodward et al, 2000)  Following a major earthquake in the San Fran area 1989, nightmare reports were twice as high after the experience (Wood et al, 1992)

20 Disturbing dreams (DDs) II Levin & Nielsen (2009) claim that the function of dreaming is fear- extinction – and that DDs indicate a failure to regulate emotions properly. Dreaming is a multi-level process  At a neural level – dreaming reflects a cohesive and interconnected network of limbic and forebrain structures underlying emotional expression and representation  At a cognitive level – dream production serves to transform fear memories generated over the days/weeks/months into dreams and nightmare imagery DDs  DDs occur because of daily emotional pressures that place a high load on emotional regulation  DDs occur because of disposition to experience highly negative emotional reactivity to events.

21 Theories of dreaming  Historical theories Ancient Greek, Egyptian theories, Medieval Theories  Psychodynamic theory (Freud) 1900 The interpretation of dreams  Physiological theory (Hobson & McCarley) 1977 Activation-synthesis theory  Cognitive theory (Foulkes) 1985 Dreamining: A cognitive psychological analysis

22 Ancient Greek & Egyptian theories  The close relationship between sleep, dreaming and emotional experience is seen widely in Greek mythology According to their theology, Oneiros, the god of dreams, helped Hypnos, the god of sleep, to reduce human suffering through sleep and dreams. The content of dreams played a significant role in explaining and rationalizing external events, not just as prophecies (Plato).  Egyptians believed that dreams were divine in origin, that is, they were generated by the gods, and were prophetic. They were a way of communicating to humans their needs.

23 Medieval theories  The start of scientific study of dreams Girolamo Cardano (1501–76) during the renaissance conducted dream interpretations – connecting dreams with emotion, and generated one of the first taxonomies of dreams (four types – corresponding to the four Hippocratic humors – blood, black bile, yellow bile and phlegm) Cardano believed that each of the humors would correspond to a different dream through “vapours,” which then would create the dream. For example, people with black bile usually dreamt of “…. darkness, earthquakes, lightning and thunder, jails, mourning…” Importantly the link is made between physiological and mental processes – and that a functional relationship between is established.

24 Freud’s proposals I  Freud was not only a psychiatrist, he was a historian and strongly influenced by the history of idea – particularly ancient mythology  “Dreams are the royal road to the unconscious” A dream is the expression of the goals of biological drives The drive activates the brain and the interaction of drive and psychological controls creates the dream  What does this imply in terms of dualism?  Are mental substances influencing physical substances?

25 Freud’s proposals II  According to Freud’s point of view, dream activity reflects man’s emotive side. Day residues consists of events of the day that become part of the dream (manifest content – is the explicit story of the dream, the latent content is the dream process that converts the underlying themes into symbolism)  Dreams were forms of “wish-fulfillment” – attempts by the unconscious to resolve a conflict of some sort, whether recent or from the recesses of the past.  He hypothesized a framework of the mind/brain that took neurobiological functions into account and connected them to psychological functions  Through Freud, the study of dream phenomena revived the ancient practice of dream interpretation and established its place in the forefront of human psychological study.

26 Contemporaries Challenges’ to Freud’s view  Maury (1861) studied over 3000 different dreams and proposed that external, rather than internal (Freud) stimuli were the catalyst of all dreams  Goblot (1886) also claimed that “we dream while we are awakening,” and that the dreams we report on awakening may be developed during the waking process.  They questioned whether dreams were truly recollections of mental processes occurring during sleep, or were manufactured during the awakening process. (this is an early version of Levin & Nielsen (2009) theory.

27 Physiological Theory  Activation-synthesis theory  Dreaming is fundamentally physiological and not psychologically driven but the brain is periodically activated, while sensory input and motor output are blocked Activation of reticular formation  Reticular activating system in the cerebral cortex regulates sleep-wake transitions (mentation) and arousal Biological rhythm of sleep-wake cycles produces activity in reticular formation, which activates various brain centres Synthesis by cortex activity  Primary sources of dreams are stimuli generated within the brain

28 Activation of reticular formation  Activations of cortex, inhibitions of motor neurons, REM, Vestibular activation, autonomic activation  Synthesis Flying experiences – vestibular activation produces disoriented spatial sense – which is rationalized as flying Chase dreams – motor cortex activation generates commands to legs, but inhibition of motor neurons means that there is no kinesthetic feedback Visual imagery – activation of the visual cortex

29 Interpretation of dreams from Physiological theory  Goal is to relate dream content to activation of different parts of the brain  Methods used to record physiological behaviors are correlated to verbal reports of dreams – and their content  This theory is limited and fails to account for the high level of coherence in the narrative of dreams as well as the association between day time emotional experiences and dream content independent of the activation of certain brain regions.  Also, built on studies assuming an association between REM and dreaming, which many later studies since have shown is not a causal association, but correlational

30 Cognitive Theory I  Foulke (1985) proposed Dreams are a form of thinking - So we should examine the representational formation of dreams (since revised by Cicogna & Bosinelli, 2001) The dream process is triggered by a widespread activation of the mnemonic contents stored in the memory systems. Three main cognitive processes involved in the generation of dreams:  1. mnemonic activation,  2. planning,  3. re-organization of representations gained during waking life

31 Cognitive Theory I 1. Process 1: The mnemonic activation is planned by a process that selects which memories should be processed and how. 2. Process 2: The planner selects the activated material and organizes it into a dreamlike narrative complete with meaning, thus elaborating a sort of first draft of the dream. 3. Process 3: These early levels of dream generation are unconscious; what people experience as a dream, however, is the result of a conscious elaboration that phenomenally represents the experience that can be partly remembered upon waking. Crucially, this theory is the first to propose an account of the generation of mental activity during sleep independent of the underlying physiological condition.

32 Pick which theory sounds most plausible to you A. Freud’s psychodynamic theory B. Activation- synthesis theory C. Foulke’s Cognitive theory

33 Question Describe and discuss what dream research (theory and evidence) tells us about unconscious processes


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