Consciousness and sleep Flashcards
What is consciousness?
A state of awareness of self and the environment
What are the 3 states of unconsciousness?
- Coma / death - progresses from clouding, drowsiness
- Deep sleep
- Unconscious mind - Unrepressed memorise and emotions can be recalled
What is clouding?
Stage of drowsiness with memory disturbances and disorientation. Impaired attention, concentration, recognition, comprehension, understanding and judgement
What is drowsiness?
Tendency to drift into sleep without sensory stimulation. Have slow actions, slurred speech, reduced reflexes and muscle tone
What defines a coma?
GCS - Reduced eye opening, motor and verbal responses
What is normal perception?
Ability to distinguish between perceiving with sense organs and imaginary. It is quantifying objectivity to see if true and real.
What is perception reliant on?
The relevance of the situation to emotions and actions. It is involuntary and independent to others’ experiences
What is a sensory distortion?
Distortion of the intensity or quality of perception and its associated feelings
What causes an illusion?
A misinterpreted perception of a sensory experience from how it was in reality.
What types of illusions are there?
Complete = Fill in missing gaps Affect = Misinterpretation due to emotional state Pareidolic = misinterpreting an obscure stimulus as clear and recongnisable
What is a hallucination?
The experience of percieving something that is not present. It is perception in the absence of a stimulus. It is spontaneous and out of the individuals control.
What is a pseudohallucination?
An involuntary sensory experience that is a hallucination but recognised by the individual to not be real.
What is the definition of sleep?
Not just the absence of waking but a regular reversible state of reduced responsiveness to external cues, that is easily reversed by meaningful stimuli.
Characterised by lack of mobility, closed eyes and reduced responses
How can sleep be measured?
EEG, eye movements and muscle tone.
Polysomnography records levels of oxygen, HR, breathing, leg and eye movements and brain waves to diagnose sleep disorders
What are the 5 stages of sleep?
Non-REM: Stage 1-4 (75% of sleep)
REM: (25% of sleep) Characterised by rapid eye movements and paralysis of muscles. Usually 4-6 cycles a night of 90 minutes. Stage of vivid dreaming.
What determines sleep/wake cycles?
Suprachiasmatic nucleus controls sleep- wake cycles through circadian rhythm via neural and endocrine regulators. Uses clock genes and oscillations. Adenosine levels are high during waking.
What mutation causes the loss of the circadian rhythm and what does it result in?
Mutation in Bmal 1 causes immediate loss of circadian rhythm when in constant darkness so light does not cause awaking.
What is narcolepsy?
Sleep-wake dysregulation with reduced REM latency causing sudden entry into sleep during the day due to inability to regulate cycles.
Characteristed by cataplexy (sudden muscle weakness from strong emotions), sleep paralysis and sensory hallucinations
What may cause sleep disruption?
Obstructive sleep apnoea Depression REM sleep behaviour disorder Parasomia Restless leg syndrome PD and MS
What may cause a circadian misalignment?
Shift work
Time zone changes
Irregular sleep wake pattern
What is parasomnia?
Occurs during stage 4 sleep causing sleep walking, abnormal movements, emotions and perceptions, night terrors whilst asleep and unaware of activity. Must prevent injury whilst in this stage
What happens in REM sleep disorder?
There is presence of muscle tone during REM with active complex behaviours. Act out dramatic dreams. Onsets within 90 minutes of falling asleep. Can remember the dream but not the actions.
What is restless leg syndrome?
A strong, irresistible urge to move legs due to an unpleasant feeling / Dysaethesia. Relieved by voluntary motor movement. The more movement is suppressed the more discomfort increases.
What is the treatment for narcolepsy?
Modafil, antidepressants and sodium oxybate
What is apnoea and the two types? How does it present?
Brief interruptions of breathing during sleep of upto 30 in one hour.
Central = control of respiration not initiated
Obstsructive = in airway
Causes arousal from deep sleep as oxygen falls and pCO2 rises.
Presents with hypertension, tiredness, irritability, poor concentration, obestity
What are the treatments options available for OSA?
Hygiene Positioning Weight loss modafil CPAP Surgery
What is insomnia?
Inadequate or poor quality sleep that can include difficulty falling asleep, Waking frequently and difficulty returning, waking early and feeling unrefreshed.
Causes lack of energy and irritability.
Can be transient for <2wks, intermittent for 2-4wks or chronic
What are the RF of insomnia?
Increased age Hyperthyroidism Female Depression/anxiety Chronic disease Substances Shift work Exercise Sleep Iatrogenic
What are the non-pharmacological treatments for insomnia?
Avoid exacerbating factors such as alcohol and caffeine and naps.
Sleep in a dark environment in a regular routine.
Recondition - Bed is only for sleep, get up and do something if not sleeping
Cognitive restructuring (not thinking about lack of sleep)
Relaxation therapy
Sleep restriction to increase drive
What are the pharmacological treatments for insomnia?
Sedatives e.g. Benzodiazepine, temazepam
What is the main worry of Pts with sleep deprivation?
Leads to errors, loss of attention and increased RTA.
