Week 5, Part II Consciousness PDF

Week 5, Part II Consciousness  Outline What is consciousness? Two major theories of consciousness Altered states of consciousness and cognition  Outline What is consciousness? Two major theories of consciousness Altered states of consciousnes...

Week 5, Part II Consciousness  Outline What is consciousness? Two major theories of consciousness Altered states of consciousness and cognition  Outline What is consciousness? Two major theories of consciousness Altered states of consciousness and cognition Two primary approaches to defining and studying consciousness: “Easy” version of consciousness -> Easy problem of consciousness “Hard” version of consciousness -> Hard problem of consciousness  Defining + Studying Consciousness Easy problem of consciousness: How is brain activity related to conscious experiences? Scientifically testable! Awareness: Experience of sensations and perceptions6 Example: Simulate neural activity to reconstruct sound of a song 6Gazzaniga et al., 2009  Defining + Studying Consciousness Hard problem of consciousness: Understand subjective conscious experiences Harder to test scientifically Qualia: ‘what it’s like’ component to consciousness Example: Is your subjective experience of a song the same as mine? Same or different experience?  Defining + Studying Consciousness How are attention, awareness, and consciousness related? Tripartite model (Dehaene et al. 2006): 3 stages of awareness result from stimulus and processing strength Interplay of exogenous and endogenous factors  Defining + Studying Consciousness States in tripartite model 1) Subliminal processing: Minimal sensory processing, no awareness 2) Preconscious processing: Sensory processing, no awareness 3) Conscious processing: Sensory processing, awareness  Outline What is consciousness? Two major theories of consciousness Altered states of consciousness and cognition  Theories of consciousness Global Neuronal Workspace (GNW): Widespread processing of information underpins conscious experiences Neural level -> experience level Unconscious things involve local sensory-motor processing Riding a bike Tying your shoes Conscious things involve widespread processing Integrate cognitive networks  Theories of consciousness Integrated Information Theory (IIT): Consciousness comes out of a complex system Experience level -> neural level Explain which types of systems have consciousness, and how much of it they have Complexity required: Feedback loops modify information, leading to consciousness Specific brain regions < architecture Case of the cerebellum as evidence for IIT  Outline What is consciousness? Two major theories of consciousness Altering consciousness affects cognition  Trance reflects shifts in direction of cognition Hove et al. (2016) Trance state = “narrowed awareness of surroundings” Experienced shamans -> brain scanner (fMRI) Rhythmic drumming to induce trance state Scan brain Question: Which brain networks are active during the trance state?  Trance reflects shifts in direction of cognition Hove et al. (2016) 1) More activity in default mode network, which is involved in inward-directed cognition Inward > outward attention  Trance reflects shifts in direction of cognition Hove et al. (2016) 2) Decreased connection between auditory processing regions Perceptual decoupling reflects less intrusion of stimuli into conscious awareness Stimulus gating  LSD affects language category representation Family et al. (2016) Background: When concepts come from similar categories, they tend to interfere with each other Interference No interference  LSD affects language category representation Family et al. (2016) Compared placebo control condition and an LSD condition Name items from similar/different categories Name each item Record verbal Question: Does LSD affect responses interference from similar language categories?  LSD affects language category representation Family et al. (2016) Lexical substitution: Call a hat “mittens” LSD group: More lexical substitutions between the similar categories Interpretation: LSD expands language category representations  Brief Recap Define consciousness: Easy and Hard Problems Two theories of consciousness Describe how alterations to consciousness can affect cognition