Parasomnias
Péter Simor, PhD.
Budapest University of
Technology and Economics,
Department of Cognitive Sciences
Outline
• Models of sleep regulation
• Macrostructure and microstructure
• Relevance of sleep disorders
• Parasomnias
• Night terror
• Sleepwalking
• RBD
• Narcolepsy
• Nightmare Disorder
Two-process model of sleep regulation
Process S: Sleep regulation under
homeostatic control
Process C: Circadian regulation determined
by genetic and environmental (eg. Light,
social timers) influences
• Sleep deprivation has a detrimental impact
on executive functions localized underlain
by prefrontal structures
• SWA (slow wave activity) during sleep in
frontal areas correlates with improved
cognitive performance after sleep
• Use-dependent increase in frontal slow
wave activity
Finelli et al
2000
Marzano
et al.&2009
Achermann
Borbély, 2003
The S – process does not regulate Sleep
per se. It regulates Slow Wave Activity
Dijk et al 1990
• Suprachiasmatic
nucleus
• master circadian pacemaker
• control of the timing of sleepwake cycles
• integrating external
information with internal bodily
„needs”
Pace-Schott and Hobson, 2002
Wulff et al, 2010
Flip-Flop
Model of sleep
regulation
(Saper et al.
2005)
Coexistence of sleep-like and wake-like
oscillations
Nobili 2011
The imbalance of sleep-like and wake-like
oscillations during sleep
• Dissociated states
• Arousal parasomnias (confusional arousals,
sleep terrors, sleep walking)
• NREM parasomnias
• REM parasomnias
Arousals during NREM and REM sleep
Transient states during sleep
Cyclic Alternating Pattern (Parma Sleep group)
CAP A types
A1 (delta 0.25-4 Hz)
A3 (alpha, 8-12 Hz)
• Sleep promotion
• preparation for awakening
• related to improved executive
functions
• „semi-opened state”
• learning, plasticity
• impaired post-sleep
executive functions
Hypnolab (R. Ferri)
CAP A2 (mixture between A1 and A3)
Delta activity
Alpha activity
Hypnolab (R. Ferri)
Relevance
• Co-morbidity
• Medication
Arousal parasomnias
• Confusional arousal
– Abrupt awakening, large amount of movements, thrashings,
inconsolable crying
– Confused state after awakening: amnesia, disorientation in time
and space
– Onset: mostly SWS, sometimes NREM2
– Very common in children, rare in adults
– NREM parasomnia
– Coexistence of NREM and WAKE states
• EEG: large amplitude slow waves with superimposed wake-like
activity
Fronto-parietal associative cortices: sleep-like activity
Motor Cortex and Cyngular Gyrus: Wake-like activity
Night terror (Pavor nocturnus)
• Abrupt arousal from SWS
• Starts with automatic movements
• Later: more coordinated movements: sitting, standing up, sometimes
running, jumping out of bed
• Emotional aspect: Intense fear, shouting
• Sympathetic activity: Heart Rate, Sweating,hyperventillation
• Cognitive aspects: amnesia, disorientation
• Memory for previous events: rare, sometimes one, simple, frightening
dream image: eg. Misfortune, dreamer as victim, aggression, apprehension
• Dreamlike mentation in night terrors was associated to daytime sleepiness
Sleepwalking
• Some common misconceptions:
• „Lunatics”, related to some traumatic event, crying and shouting if
awakened
• Onset in SWS sleep
• First uncoordinated movements, mumbling, but later more
coordinated, goal-oriented behavior (eating, walking, aggressive or
sexual behavior)
• EEG: cortex-(hyper)synchronization; motor cortex:
desynchronization
Sleep walking epsiode with SPECT
• Activation in thalamocingulate pathways
• Deactivation in thalamocortical, arousal-related areas
Dreams during
sleepwalking are
related to the
enacted behaviors
• Sleepwalking vs. quiet SWS: activation in
vermis and posterior cingulate cortex:
•residual cognitive functions:
navigation, goal-oriented behavior,
motor programs, stereotyped
behavior
• Sleepwalking vs. normal controls:
deactivation in frontoparietal areas:
• confusion, amnesia.
Basetti et al, 2000
Sleep paralysis
• REM parasomnia
• inablility to move
• Anxiety, fear
• Hallucinations
• Dream-like experiences mixed
With environmental awareness
• Incubus
• Felt presence
• Out of body experiences
Terzaghi et al. 2000
Very commom condition in narcolepsy
• sudden REM sleep onset
•sleep paralysis
• hypnagogic hallucinations
• cataplectic attacks
• more phasic REM sleep (muscle
movements, eye movements)
• more superficial sleep (stage 1)
• more intense dreaming
Narcolepsy
• Prevalence 0.02-0.03 %
• Deficiency in hipocretin (orexin)
• Cholinergic hipersensitivity (cholinerg agents in
narcoleptic result in sleep, in healthy subjects they
induce alertness)
• can be triggered by emotional stimuli
• VIDEO
Rem Behavior Disorder
•
•
•
•
Degeneration of cells inducing motor atonia during REM sleep
„Enacted dreams”
Prevalence: 0.5 %
Neurodegenerative disorder
– Parkison, Lewy Body dementia, multiple system atrophy (alpha
synucleopathies)
– VIDEO
Nightmare disorder
• Intense, disturbing mental experiences that often awaken the
dreamer (from REM or late night NREM sleep)
• Weekly basis
• Detailed, vivid recall of the emotionally negative dream
experience
• Alertness is full immediately on awakening, with little confusion
or disorientation
• The dream experience causes clinically significant distress or
impairment in social, occupational, or other important domains
DSM-IV-TR, 2000; ICSD-II, 2005
Prevalence
• Epidemiology (2-6%)
• Adults vs Children (4 % vs. 30%)
• Nightmares across the lifespan
Nielsen & Zadra (2010)
PTSD vs. Idiopathic Nightmares
Nightmare topics:
• Falling
• Being chased
• Paralyzed
• Threatening sorroundings
• Death of close persons
• Being attacked physically
• Unable to complete a task
• Accident
• Threatening animals
• Natural disasters
Schredl (2010)
Secondary symptom or Core Sleep Disorder?
•
Psychiatric perspective

Co-morbidity with
mental complaints







PTSD
BPD
Depression
Anxiety
Schizotipy
Dissociation
Suicide
Tendencies
• Sleep Medicine Perspective
 Co-morbidity is not
evident if we examine
mental complaints
among a group of
nightmare sufferers
instead of the other
way around
 Mediating factors
 Nightmare distress
 Personality
Spoormaker et al. (2006, 2008)
Personality
 Day-dreaming, imagination, creativity
 Neuroticism, emotional vulnerability
 Opennes to experience
 Difficulty in separating the content of different mental
states
(past-present, reality-fantasy, self and the other, etc.)
 Increased dream recall
 More complex, bizarre,
intense dreams
 Nightmares
 Lucid dreams
Independence of nightmares from mental
complaints
• PTSD: nightmares persist after the remission of waking
symptoms (Montgomery et al, 2005)
• Dream Logs: occurence of nightmares is not related to daily
variations of anxiety symptoms (Wood et al, 1990)
• Genetic studies: The high genetic heritability of nightmares
is independent of the heritability of anxiety symptoms
(Coolidge et al, 2010)
Altered sleep and nightmare frequency
• Nightmares are associated with poor subjective sleep quality (Li
et al, 2011; Schredl, 2003)
• Higher rate of nightmares in sleep disordered (insomnia, REM
behavior disorder, Narcolepsy) patients
• Nightmares are related to the subjective severity of sleep
problems (Krakow 2006)
• Few studies investigating objctive sleep
parameters (small sample size, without
controlling the confounding factors)
17 NM and 23 CO subjects spent 2 consecutive nights
in the sleep laboratory. The sleep architecture based on the
undisturbed full-night recording of the second night was
examined.
We controlled for the effects of
STAI-T and BDI (depression) scores
on our dependent variables
Fragmented sleep in nightmare disorder
p = 0.002
p = 0.007
p = 0.018
p = 0.027
0.48
pp==0.005
STAI,
BDI-H
Imbalance of sleep promoting and
arousing influences during sleep?
Simor, Horváth et al (2012) Eur Arch Psych Clin Neurosci
Imbalance of sleep promoting and arousing
influences
Simor et al. (2013) SLEEP
Relative spectral power analyses (19 NM, 21 CO)
NREM, REM periods
Cz electrode
7.75-9 Hz
10-14.5 Hz
Simor et al, (2013) Biol Psychol
Correlations between NREM low alpha and REM
high alpha
NIGHTMARE SUBJECTS
CONTROL SUBJECTS
R = 0.22
R = 0.78
P < 0.0001
P = 0.33
Correlation between nightmare severity and posterior
EEG (O1,O2,Pz,P3,P4) activity in REM sleep in the
nightmare group
9-13.5 Hz
frequency
frequency
REM high alpha power peaked at posterior
locations
Wake-like EEG feature?
Back to psychology and to the land of speculations
• Arousals, wake-like oscillations – perceptually vivid, intense, real-like
imagery, increased dream recall
• Thin boundaries – absorption in dream images, fusion of dream and
reality
• Negative emotionality and inefficient emotional regulation –
activation of fear-related memories, environmental threats
• Alert non-restorative sleep
Thank You For Your Attention
This research was realized in the frames of TÁMOP 4.2.4. A/1-11-1-2012-0001
„National Excellence Program – Elaborating and operating an inland student and
researcher personal support system”. The project was subsidized by the European
Union and co-financed by the European Social Fund.