Consciousness Lecture 1 PDF

CONSCIOUSNESS PSY1005S Lecture 1: Consciousness & Sleep2024 Joel Saboi Mvula [email protected] Alexa Soule...

CONSCIOUSNESS PSY1005S Lecture 1: Consciousness & Sleep2024 Joel Saboi Mvula [email protected] Alexa Soule [email protected] om  Outline of Lectures 1. Consciousness & Sleep 2. Sleep Disorders 3. Psychoactive Drugs: Definitions & Aetiology 4. Psychoactive Drugs: Dependence Mechanisms 5. Psychoactive Drugs: Specific Drugs  Understandin Understandi The g and ng what can importance defining cause and role of what altered sleep consciousnes states of Learning s is. consciousne biologically. Outcome ss. sLecture 1 The mechanisms of Understanding the circadian rhythms basic systems of and its role in sleep. sleep.  What is consciousness? https://www.ted.com/talks/ michael_s_a_graziano_what_is_consciousness? utm_campaign=tedspread&utm_medium=refe rral&utm_source=tedcomshare  What is Consciousness? Some definitions: Cognitive Neuroscience Useful definition Global Workspace theory consciousness is consciousness is your = spotlight of selective attention generated by a set of awareness of everything action potentials in the around you and inside your communication amongst own head at any time, neurons just sufficient to including your thoughts and produce a specific feelings, which you use to perception, memory or organise your behaviour experience in our awareness  Altered States of Consciousness o Consciousness is a spectrum (i.e., levels) o States of consciousness Waking consciousness Are animals conscious? o Altered states of consciousness Day-dreaming; drugs; meditation; hypnosis Sleep  Sleep in healthy o individuals Circadian rhythms o How much sleep is enough? o Why do we sleep?  Circadian Rhythms Sleep-Wake cycle Sleep is controlled by circadian rhythms Melatonin Cycle Light enters eye SCN Pineal gland Secrete (hypothalamus) melatonin Think about the influence of blue light screens before bedtime  Why do we sleep? We spend a Sleep is found considerable across species amount of our and classes of lives in a state animals of sleep All mammals Aquatic animals such as dolphins and fish Birds Reptiles  Young Highly adults variable in need 7-9 individuals How much hours per Short vs. long night sleepers sleep is enough? Influence d by Amount of lifestyle sleep factors needed decreases with age  Sleep Composition N1 o Active type of (NREM) REM (Rapid Eye sleep Movement) Sleep o Most dreaming o Voluntary muscles are inhibited N2 RE (NREM) M o Deeper NREM (Non-Rapid o More restful Eye Movement) o Free to move Sleep around N3 (NREM)  NREM Stages N1 = light sleep N2 N3 = deep sleep o Brain wave activity slows down o Deeper sleep where temp drops, HR o Slowest & deepest brain waves o Some dreaming (hallucinations) slows, breathing shallow & irregular o Deep sleep = SWS (slow wave sleep) o Brain waves slow down o Hypnic jerks o Body at lowest level of functioning o See sleep spindles on EEG o Theta waves increase (alpha waves o Mostly delta waves falls away) o Mostly theta waves o GH released for children  REM Sleep REM (R) Sleep o Body temp increases o Eyes move rapidly o HR increases o Brain waves mostly beta (usually signal for wakefulness) – but still asleep o Most vivid, detailed, longer, bizarre, emotional dreams  Sleep Stages o Cyclic nature of these stages Called sleep cycle Usually 90min on average to go through N1 -> N2 -> N3 -> N2 -> REM and then repeat (4-5 cycles per night) Waking during the night would usually be after a REM stage o Beginning of night – SWS longer and REM shorter As the night goes, SWS becomes shorter, and more sleep is occupied with REM Sleep in Healthy Individuals EEG or PSG - Used to measure brainwave activity Awake: beta waves Drowsy: alpha waves N1: theta waves increase (replacing alpha waves) N2: Sleep spindles; theta waves N3: delta waves (slow) REM: beta & gamma waves - "paradoxical sleep"  Why do we sleep? Restorati Memory Emotion on consolidation regulation  Functions of Sleep Function of nREM sleep Function of REM sleep o Redistribution of memory traces o Leads to Long-Term Potentiation from hippocampal networks to (LTP) the neocortex i.e., long-lasting strengtehning of synaptic o Weakly potentiated synapses are connections  memory consolidation eliminated o Dreaming o Physical restoration (tissues, Psychological functions: problem-solving, muscles, bones, immune system) emotional processing o Mood regulation (mood o Restoration of brain function disorders can be present when sleep is poor)  Sleep Deprivation SLEEP IS IMPORTANT! Even a few nights of poor sleep can have consequences for physical & cognitive functioning Examples: angina, arthritis, depression, chronic lung disease, impaired cognition  The evidence is overwhelming, it is irrefutable. Sleep is the single most effective thing you can do to reset your brain and body health each and every day Matthew Walker Any questions?