Freud's Theory of Consciousness

• Consciousness is an individual's knowledge and awareness encompassing thoughts, sensations, and memories.
• Experience of consciousness refers to an individual's awareness of their mental activities and surroundings.
• Concentration alternates effortlessly between focus, imagination, and distraction.
• William James describes consciousness as a stream or river.
• A sense of identity is provided by an unbroken experience of consciousness.
• Psychological, physiological, social, and cultural factors all contribute to consciousness.
• The lesson aims to explain the physiology of sleep, the different stages of sleep, and also will highlight some disorders of sleep

Freud's Theory of Consciousness

• Human consciousness is divided by Sigmund Freud into three levels: conscious, preconscious, and unconscious.
• Freud's id, ego, and superego align with these levels.
• The conscious level contains things an individual is aware of, including self-knowledge and surroundings.
• The preconscious level holds things that an individual could pay attention to, that also stores easily retrievable memories.
• The preconscious are thoughts not repressed but available for recall.
• The unconscious includes memories, thoughts, and urges outside of conscious awareness.
• Unpleasant or conflicting content resides in the unconscious.
• Behaviour is influenced unconscious elements.

Physiological Influence of Consciousness

• Biological and environmental clocks are also referred to as physiological influences of consciousness.
• It examines sleep and awake cycles.
• The highest mental activities occur between 8-10 am and 8-9 pm.
• Circadian rythms are biological processes that systematically change over a 24 hour period and create fluctuating levels of consciousness.
• Changes in blood pressure, temperature, hormone secretion, and sensitivity to pain are changes that occur during circadian rhythms.

Circadian Rhythm

• Suprachiasmatic nucleus (SCN), a cluster of neurons in the hypothalamus controls sleep-wake cycle.
• SCN acts as an internal controller or pacemaker and guides the timing of the circadian rhythm.
• Sunlight influences the circadian rhythm.
• Decrease in sunlight stimulates melatonin hormone production in the pineal gland, also known as the sleep hormone.
• 1-3 am is when melatonin production is at its highest.
• The pineal gland stops melatonin production before sunrise.
• Sunlight exposure informs the SCN that it's time to wake up through the brain's visual center.
• Sunlight allows for synchronization of SCN operations to a 24-hour schedule.
• With absence of sunlight or changes in time zones, the body follows a 25-hour cycle.
• Disruption of this rhythm leads to disturbances in thinking, concentration, memory, and physical/mental fatigue and is referred to as jet lag.

Understanding Sleep

• Sleep is an active state of unconsciousness where the brain rests and reacts to internal stimuli.
• The exact purpose of sleep has not been fully determined.
• Sleep is important for brain function, and communication between nerve cells.
• The brain and body remain remarkably active during sleep.
• Recent findings suggest that sleep plays a housekeeping role by removing toxins that build up during wakefulness.

Sleep Cycle

• Sleep is divided into two types: REM(Rapid Eye Movement) and NREM (Non-Rapid Eye Movement)
• Sleep begins with conscious preparation.
• Brain produces small, fast waves known as Beta brain waves.
• Body muscles relax, the eyes close, and producing higher and slower brain waves known as Alpha brain waves.
• People may experience Hypnagogic hallucinations, such as hearing their name or feeling like they're falling or floating.
• Feeling like falling as a sensation can lead to a myoclonic jerk or involuntary muscle spasm that can wake up someone.
• REM is also known as "paradoxical sleep"
• rapid eye movement Dreaming Awake occurs during REM
• There is increased autonomic activity during REM
• Procedural memories consolidate during REM
• Slow wage sleep occurs during NREM. (stages 3,4)
• Declarative memories consolidate during NREM

NREM Sleep

• NREM occurs in the first 90 minutes of sleep and is divided in 4 stages.
• During Stage 1, slower Theta Waves replaces alpha waves.
• An individual loses touch with reality or the outside world and all familiar sounds/smells disappear.
• Stage 2 consists of Sleep spindles for a few seconds followed by slower brain activity.
• breathing becomes rhythmical
• Delta waves replace Theta waves after 15-20 minutes of sleep.
• NREM Stage 3 & 4 are slow-wave sleeps.
• There is increased Delta brain activity- 20% in stage 3 and 50% in stage 4.
• Begins from 20-40 minutes after sleep.
• Heart rate, blood pressure, and breathing are at their lowest.
• A person loses complete contact with the environment where sleepwalking can occur.
• Deep relaxation happens during stage 4.
• Once stage 4 is reached, the cycle falls backwards into stage 2.

REM Sleep

• Brain becomes more active, generating smaller and faster brain waves
• Visual and motor neurons are active during REM.
• Dreaming occurs during the REM phase.
• Brain activity is kept active although voluntary muscle activity is inhibited.
• Eye movement increases, heart rate, blood pressure and respiration fluctuates up and down during REM
• First episode of REM sleep happens after 90 minutes.
• REM becomes longer and NREM becomes shorter as the night progresses.

Biological Needs for Sleep

• Without sleep, people experience disruptions in mood, mental abilities, slower reaction time and slower perceptual skills.
• Sleep promotes/allows physiological processes to restore/rejuvenate body/mind according to restoration theory.
• NREM allows secretion of hormones such as growth hormones and testosterone.
• REM is essential for infants and young children due to promoting brain development.
• Sleep is needed for memory consolidation, immune system optimization, reduction of oxidative stress, and regulation of hormones
• A healthy sleep optimizes cognitive function, cardiovascular system, immune response, and metabolism (possibly can promote in weight loss)
• Factors that affect sleep quality include medications, travel, alcohol and caffeine, screen time, and physical activity.
• Common sleep problems include insomnia, hypersomnia, sleep apnea, restless leg syndrome, narcolepsy, stress- and anxiety-induced sleep disturbances, and teeth grinding

Sleep Disorders

• Sleep disorders are defined as disturbances in normal sleep patterns that disrupt daytime function leading to subjective distress.
• Sleep disorders include insomnia, disorders of NREM and REM

Insomnia

• Characterized by difficulties falling or staying asleep
• It is common in the adult population
• Stressful life events, pressure, or relationship problems can cause it.
• Treatments include behavioral/psychological techniques and educating sufferers on sleep hygiene.
• Medication may affect normal sleep cycle leading to dependence and addiction.

Disorders of NREM

• sleepwalking (somnambulism):
• occurs in the 3rd/4th stage of NREM
• sitting up, getting out of bed, moving slowly, poorly coordinating automatic movements with a blank look.
• an individual can move without difficulty or hurting self
• The person may not be aware of the surroundings.
• They may dress/undress, eat, or go to the bathroom inappropriately.
• There is no recollection of the movement when awake.
• Night terrors: These are sleep terrors that are common in children
• Characterized by more intense fear than experienced during a nightmare
• A person is characterized by increased physiological arousal such as intense fear, restlessness, sweating, rapid heart rate that takes a few minutes to calm down
• There is no recollection the next morning.

Disorders of REM

• Sleep Apnea: A sleeper that repeatedly stop breathing during sleep due to a built up of carbon dioxide.
• Breathing may stop for at least 10 seconds.
• 300 episodes of sleep apnea can occur in just one night.
• An individual may not remember waking up because of it.
• The sleeper report experiencing tiredness or drowsiness.
• Sleep Apnea is common in older men.
  • Therapies for sleep apnea: positive airway pressure (PAP) devices and oral appliances.
  • Surgery is recommended when non-invasive devices fail.
• Lifestyle changes like doctor-prescribed therapy.
• Narcolepsy: A daytime sleep disorder.
• Symptoms: excessive daytime sleepiness, brief lapses into sleep throughout the day
• The sleeper experience hallucinatory-like REM sleep and sleep paralysis
• The disorder runs in families and begins in adolescence, which is chronic
• Treatment: Scheduled daytime sleeping and using stimulants.

Revision Questions

• William James described consciousness as a "stream of consciousness"
• According to Freud an individual's preconscious thoughts can be easily accessed.
• To transition from wakelfulness to sleep is the primary function of Stage 1 NREM sleep
• Of the following sleep disorders sleep apnea is characterized by recurring episodes of sleep apnea.
• Alpha and Theta waves replaces brain waves during Stage 1 NREM.

True or False

• Consciousness refers to the state of awareness of one's surrounding and thoughts - True
• Unconscious level contains thoughts and memories which can be easily accessed - False
• REM is characterized by slow brainwaves and lack of dreaming - False
• Sleep apnea is characterized by recurring episodes of insomnia - False
• Stage 3 of NREM is also known as slow-wave sleep -True

Subjective Questions

• Driving home in 30 minutes with no memory - Altered state of consciousness
• Trouble of breathing- Sleep Apnea
• person in coma- unconscious
• Vivid Dream with similar brain waves like wakelfulness- REM Sleep
• Feeling tired and groggy after waking up- NREM Sleep