Lecture 7 - Sleep and Pathology PDF

Lecture 7 - Sleep and Pathology Overview Sleep Basics Sleep disorders PTSD Depression & Insomnia Sleep Staging An assessment of sleep architecture is an important tool to discover abnormal sleep patterns...

Lecture 7 - Sleep and Pathology Overview Sleep Basics Sleep disorders PTSD Depression & Insomnia Sleep Staging An assessment of sleep architecture is an important tool to discover abnormal sleep patterns How are hypnograms created? Sleep staging Divide recording into non-verlapping 30-s epochs Assign each epoch a sleep stage through visual inspection ** N3 ** ** REM ** N2 Wakefulness Age related changes in sleep patterns Memory Consolidation Relies on a reactivation of newly encoded information Labile information is gradually transformed into long-lasting memory traces It is mediated by an intricate interplay of different sleep rhythms Circadian Rhythms Our body and behaviour follow an inner clock ’Clock genes’ are found in almost every organ or tissue  The strongest pacemaker is the sun Sleep Regulation Similarly, sleep is regulated by rhytmic processes: Circadian rhyth,s regulate our inner sleep clock This process interacts with ‘sleep pressure’ Sleep Disorders Categories A study in 2024 with 2000 adults showed that 90% reported sleep problems 2/3 of them for more than 6 years Sleep problems are becoming a pandemic but are hard to quantify given the different manifestations Non-organic sleep disorders Insomnia Difficulty falling asleep and staying asleep and/ or non-restorative sleep and/ or early morning awakenings for at least 3 months and at least 3 nights per week. The sleep disorder affects the patient’s social/ occupational functioning. It occurs despite adequate opportunity to sleep Disruption of the sleep-wake rhythm a sleep-wake cycle disorder is defined as a lack of synchronisation between the individual  sleep-wake cycle and the desired sleep-wake cycle of the environment. This leads to complaints of insomnia and hypersomnia Sleepwalking or Somnambulsim A state of altered consciousness in which sleep and wakefulness are combined. During an episode, the person leaves the bed, walks around, shows a reduced level of consciousness, reduced reactivity and dexterity. After waking up, there is usually no memory of the sleepwalking. Pavor nocturnus Nocturnal episodes of extreme fear and panic with violent crying, movements and strong autonomic arousal. The affected person sits or stands up with a cry of panic. They often rush to the door as if to escape, but usually without leaving the room. After waking, there is no memory of what happened or it is limited to fragmented images. Nightmares or Anxiety dreams Dream experience full of fear or dread, with a very detailed memory of the dream content. This dream experience is very vivid, with themes such as threats to life, safety or self- esteem. There is often a repetition of the same or similar frightening nightmare themes. During a typical episode there is autonomic stimulation, but no perceptible screaming or body movements. After waking up, the patient quickly becomes lively and orientated. Organic Diseases Chronic kidney or gastro-intestinal disease Chronic pain Epilepsy Heart and lung disease Headaches Stroke Multiple sklerosis Or substances: Alcohol Antibiotics Anti-dementia drugs bloodpressure meds hormone supplements  stimulating substances Hypersomnia Sleep Apnea Symptoms Snoring pauses in breathing headaches not restorative sleep daytime tiredness prevalence 2-4% of population increases to 10-20% with higher age risk factors obesity males Quanitified Treatment There are several treatment options Most common: losing weight and no alcohol Medication Protrusion splint continuous positive airway pressure machine (CPAP) lying sidewise Comorbidity of Sleep Disorders 20-40% of psychiatric patients suffer from slepe problems sleep problems can be risk factors, predictors or symptoms of a mental disorder often sleep problems persist after treatment PTSD Emotional Memory Memories are not just bundles of information They often hold additional properties all of these properties affect how sleep promotes their consolidation one of the most important properties is the emotional valence Emotional memory composed of memory & affective tone Consolidation How do emotions affect memory? Split-night design Neutral and negative text Memory measure: recalling story details Sleep consolidates declarative info but REM sleep is selective for emotional content Emotional Valence 12 hr sleep/ wake design Exposure to emotional images in fMRI scanner Sleep reduced amygdala activation valence ratings for most intense ratings Emotional regualation REM sleep consolidates emotional memories and reduces the affective blanket over time only a memory of an emotional memory remains Sleep and PTSD Healthy/ restorative sleep promotes resilience against trauma Disturbed sleep before/ after a trauma increases risk to develop PTSD Symptoms: Nightmares  Insomnia hypagogic & hypnopompic hallucinations frequent awakenings reduced deep sleep increased REM density and fragmentation Behavioural PTSD therapy & Sleep Imagery rescripting is a psychotherapuetic approach to modify aversive memories by integrating of novel and adaptive information via imagination Reduces arousal and changes the meaning of emotional experiences Imagery Rescripting & Sleep Sleep amplifies change in physiological distress Change in heart-rate linked to sleep spindles Intrusive Thoughts Maladaptive processing of emotional memories during sleep is one side of a coin Another harmful symptom of PTSD are recurrent intrusive thoughts ruminating about traumatic experiences cna in turn affect sleep Mechanism Impaired memory supression Memory supression Memory suppression can be very beneficial Weakens memory traces  Prevents future intrusions Renders negative memories less aversive PFC is central for memory suppression and sensitive to sleep loss Sleep deprivation experiment Sleep vs sleep deprivation Affect-evaluation: rating of many scenes Think/ no think task face-scene pairs Retrieval: faces with green or red frame More intrusions after sleep deprivation memory suppression after sleep depotentiates negative memories Brain activation during suppression after sleep deprivation is lowered in PFC increased in HC Depression Depressive disorder involves a depressed mood or loss of interest for long periods with severe dificulties in all aspects of live Prevalence: 3-5% of population and more common in females than men Symptoms: poor concentration excessive guilt or low self-worth disrupted sleep thoughts about dying/ suicide tiredness or low-energy Depression is accompanied by a variety of sleep alterations REM and depression REM sleep alterations were long thought to a biomarker for depression However, findings were confounded by age and sex, also other mental disorders display REM alterations But people with depression are more vulnerable to early REM onset upon cholinergic stimulation Circadian Disruption Circadian rhythms appear to be phase-advanced 6-hour advanced sleep schedule delays REM onset, shortens 1st REM episode & reduces depressive symptoms long-term Full-night sleep deprivation acts anti-depressive by counteracting a deficient S-process Insomnia 10% of population suffers from insomnia Insomnia increases with age and is more prevalent in women Health risks: heart attacks high BP Obesity substance addiction anxiety or suicidal tendency Insomnia & depression Bi-directional relationship between depression & insomnia almost all depressed patients suffer from insomia insomnia increases risks for depression Insomnia is not only a symptom of psychopathology, but a comorbidity Treatment of insomnia is essential Insomnia Treatment Most common treatment: CBT for insomnia Restructuring of thoughts, feelings and behaviours to counter insomnia Efficacy in insomnia patients Clinically significant results remained after one year CBT-I in other psychopathologies CBT-I in patients with PTSD Large effects on sleep latency, awakenings and sleep efficiency Small to medium effect on PTSD and depression symptoms CBT-I in depression Large effects on insomnia Reduction of depressive symptoms found as well Treatment of sleep-related symptoms could be mediator for reduction of depressive symptoms CBT-I in detail addressed three main pillars underlying insomnia Hyperarousal Sleep-imparing cognition Dysfunctional sleep habits Hyperarousal Physical and mental relaxation techniques are part of clinical guidlines  Breathing techniques meditation guided imagery Medium to large effects on problems of falling asleep & maintaining sleep Sleep-impairing cognition Uncover thoughts and concerns leading to fear, anger and tension Mitigate worries about consequences and dangers of sleep problems Manipulate thoughts with distraction techniques Dysfunctional sleep habits Stimulus control bed & bedroom are associated with sleep instead of a battle for sleep Sleep hygiene: Establish conditions and routines that affect sleep positively Stimulus control In essence, stiulus control is a simple equation #PS495