Consciousness

"Global" consciousness and brain states "Consciousness is "modulated rather than generated by the senses" Llinas et al., 1998

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Split brain patients and "split consciousness" Chicken foot to left hemi: Points to chicken Winter scene to right hemi: Points to shovel Better performance than unitary Confabulates: "The shovel is used To clean the chicken coop"

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These 40 Hz osc are generated by thalamocortical loops Damage to this loop can cause lethargy and coma Low frequency events and sleep Relationship to stimulus binding?

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SLIDE 14 Anesthesia and brain state -*Anesthetics drastically affect brain state, and produce sleep-like states* -*Anesthetics affect different areas of brain in different ways* -One notable site of decreased activity is thalamus (may relate to cortical inactivation) -Changes in global network connectivity

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Language and consciousness What is consciousness for? Why did it evolve?is language necessary for full self-consciousness? -the importance of social cognition and deception for the evolution of consciousness

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Are these "microconsciousnesses" really conscious? E..g. for fast-moving stimuli, V5 can activate sooner than V1 (due to a direct projection from pulvinar?), implying the ability to form a conscious percept of motion in isolation (from V1). Problems: Major problem: all human subjects are conscious (although animal correlates use anesthetized How are microconsciousness integrated into a unified whole?

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Searle, JR (2000) "Consciousness" Ann. Rev. Neurosci. 23: 557 Resistance to the problem 1. Not an ________ question for neuroscience 2. ________ 3. Problem in ________ the problem

appropriate premature defining

Binocular rivalry and gestalt switching: Constant stimuli with _______ ______ percepts Rivalry: present _______ stimuli to each eye: only _____ is perceived

differing conscious different one

What is consciousness? Opinions and definitions vary 3. ______ ______ mental states about other mental states (i.e. a pain is not a conscious state, but worrying about a pain is) 4. _______ (perceptual consciousness)

second order awareness

What is consciousness? Opinions and definitions vary 2. States of _____ ________ (sense of self as agent)

self consciousness

Pathways for visual information to cortex Retina->_______ ______->pulvinar (thalamus)->______ _____

superior colliculus extrastriate cortex

"Microconsciousness": the building block model "Consciousness is not a _____ faculty, but...it consists of many micro-consciousnesses." "Activity at each stage of node of a processing-perceptual system has a conscious _______. Binding cellular activity at different nodes is therefore _____ a process preceding or even facilitating conscious experience, but rather bringing different conscious experiences together." (Bartels & Zeki, 1998)

unitary correlate not

What are the 3 Essential features of consciousness? 1. _______ (all states have their own "feel") 2. ________ 3. _____ (single point of view)

Qualitativeness Subjectivity Unity

What is consciousness? Opinions and definitions vary 1. " Consciousness consists of inner, qualitative, subjective states and processes of sentience or awareness." (Searle, 2000) Is this a good definition?

inner subjective awareness no

Feature Binding and synchrony A bound stimulus can exhibit ______ ______ in the gamma band than a ____-______

more synchrony non bound

Blindsight Patients with damage to ______ ______ ______ perceive stimuli without _______ awareness of them. -behavior -______ ______ (color, motion, etc) -emotion

primary visual cortex conscious stimulus detection