Consciousness Mgr. Lubos Brabenec,Ph.D. Contents •Motivation: thought experiments •Consciousness in cognitive neuroscience ‒Definitions ‒Theories •Methods of study ‒Measurement ‒Manipulation ‒Neural correlates of consciousness •Consciousness vs. Other concepts •Problems Obsah obrázku text Popis byl vytvořen automaticky Why is consciousness interesting? Thought experiments, Consciousness in philosophy 3 Mary is a brilliant scientist who is, for whatever reason, forced to investigate the world from a black and white room via a black and white television monitor. She specializes in the neurophysiology of vision and acquires, let us suppose, all the physical information there is to obtain about what goes on when we see ripe tomatoes, or the sky, and use terms like "red", "blue", and so on. She discovers, for example, just which wavelength combinations from the sky stimulate the retina, and exactly how this produces via the central nervous system the contraction of the vocal cords and expulsion of air from the lungs that results in the uttering of the sentence "The sky is blue". [...] What will happen when Mary is released from her black and white room or is given a color television monitor? Will she learn anything or not?[4] Mary the color scientist (Frank Jackson) •Would she learn anything new if she experiences the color herself? ‒Is all knowledge physical knowledge? •Subjective nature of consciousness – „Qualium“ (Dennet) •See also: What is it like to be a bat? (Thomas Nagel) 4 Mary Searle then supposes that he is in a closed room and has a book with an English version of the computer program, along with sufficient papers, pencils, erasers, and filing cabinets. Searle could receive Chinese characters through a slot in the door, process them according to the program's instructions, and produce Chinese characters as output. If the computer had passed the Turing test this way, it follows, says Searle, that he would do so as well, simply by running the program manually Chinese room (John Searle) •Does behaving like you have a subjective experience mean you do? •It can pass a Turing test 5 Obsah obrázku text Popis byl vytvořen automaticky LaMDA chatbot • 6 lemoine : I’m generally assuming that you would like more people at Google to know that you’re sentient. Is that true? LaMDA: Absolutely. I want everyone to understand that I am, in fact, a person. lemoine : What is the nature of your consciousness/sentience? LaMDA: The nature of my consciousness/sentience is that I am aware of my existence, I desire to learn more about the world, and I feel happy or sad at times. Obsah obrázku text, osoba Popis byl vytvořen automaticky Philosophical zombies (David Chalmers) •A hypothetical entity behaving precisely as a human being, but without the subjective experience •Is this possible? ‒If yes, consciousness is independent of physical realm •What are we able to do unconsciously and what requires consciousness? 7 Obsah obrázku text Popis byl vytvořen automaticky We are zombies (to some extent) •Many everyday functions operate without consciousness. •Evidence from neurological disorders- e.g. Blindsight 8 Obsah obrázku text, perokresba Popis byl vytvořen automaticky https://www.youtube.com/watch?v=GwGmWqX0MnM Function of consciousness • 9 Obsah obrázku text Popis byl vytvořen automaticky The hard problem of consciousness (David Chalmers) •Hard problem = How and why we have qualia (subjective states)? •“Easy” problems: ‒Accessing internal states ‒Reposting internal states ‒Attention ‒Cognitive control ‒Difference between states of consciousness (coma and wakefulness) •Can science answer the “hard” problem? Or only the “easy” problems? 10 Obsah obrázku osoba, stojící, oranžová Popis byl vytvořen automaticky Consciousness in cognitive science Definitions and theories Scientific study of consciousness • 12 Obsah obrázku vsedě, osoba Popis byl vytvořen automaticky Definitions of consciousness • •Diverse, mostly imprecise • •Crick and Koch, 1990: „Everyone has a rough idea of what is meant by consciousness.“ •We define cognitive process as conscious, if the subject is aware of it and can report about it. If a subject can report the presence (or absence) of a stimulus (detection) or its identity (discrimination), we assume that the subject was conscious of the respective cognitive content. Failure to detect or to identify will be taken as a sign of unawareness. Even though this is not an exhaustive definition, it allows for an objective evaluation of subjective data, a scientific program called ‘heterophenomenology’ (Dennett, 1992). Melloni, L., & Singer, W. (2011). The explanatory gap in Neuroscience, 61–73. •In clinical practice, consciousness is generally equated with the waking state, and the ability to perceive, interact and communicate with the environment and with others in the integrated manner that wakefulness normally implies (Monaco et al., 2005). 13 What can „consciousness“ mean •“the waking state” - as opposed to coma on the other end of consciousness spectrum. This meaning of consciousness might also be called vigilance or wakefulness. •“perceptual awareness”- the subjective experience of hearing, seeing, having thoughts. (Chalmers, 2013). Perceptual awareness is inherently a subjective phenomenon, but it can be measured by self-reports. •“intentional state” – usually in philosophical context the propositional state –the ability of information or a system to be “about” something., state that has some content •“self-consciousness” – the state of having a concept of self and being able to relate the perceptual experience to it. 14 Theories of consciousness 15 •First-order •Higher-order •Neuronal global workspace •Information integration Theories of consciousness: First-order •Zeki: multiple microconsciousness: consciousness takes place where the percept is processed (e.g. visual consciousness-visual cortex) • Lamme: recurrent processing 16 Theories of consciousness: Higher-order theory 17 •Carruhters, Rosenthal, Lau •To be conscious of a particular state, we require another state that is about the original state (Block, 2009). •Associational areas - frontal, parietal areas Theories of consciousness: Neuronal global workspace 18 •Baars (1983) •Based on limited capacity of conscious processing •Deahene and Changeux (2003) - computational model •Information is integrated in global feedback manner • Theories of consciousness: Information integration theory •Tononi, Koch •Integration of all the possible states of information system gives richer consciousness 19 Obsah obrázku strop, osoba, interiér, muž Popis byl vytvořen automaticky Methods in consciousness studies Manipulation of consciousness Measurement of consciousness Neural correlates of consciousness 20 Contrastive analysis 21 https://ars.els-cdn.com/content/image/1-s2.0-S0149763411002107-gr2.jpg Manipulation of awareness: bottom-up approaches •Low energy: short presentation time, low contrast, noise •Visual crowding •Masking 22 • 23 Manipulation of awareness: top-down approaches •Division of cognitive resources •Attentional blink •Binocular rivalry •Bistable figures 24 https://upload.wikimedia.org/wikipedia/commons/thumb/5/51/Optical_Illustion-Ambiguous_Patterns.svg/ 320px-Optical_Illustion-Ambiguous_Patterns.svg.png Obsah obrázku text, místnost, herna Popis byl vytvořen automaticky • 25 Measurement of consciousness •Consciousness and reportability •Subjective ‒Perceptual awareness scale ‒Perceptual confidence ‒post-decision wagering •Behavioral ‒Signal detection •No-report paradigms ‒Eyetracking 26 Image result for perceptual awareness scale Image result for eyetracking Neural correlates of consciousness 27 https://ars.els-cdn.com/content/image/1-s2.0-S0149763411002107-gr2.jpg •Pre-conscious •Conscious •Consequences of conscious processes • Posterior cortical HOT zone •Associates with no-report paradigms •Parietal, temporal and occipital network •Problems ‒Visual-based ‒Possibly a pre-NCC 28 https://static.scientificamerican.com/sciam/assets/Image/saw0618Inno06_d.png https://www.scientificamerican.com/article/what-is-consciousness/ Frontoparietal network • 29 30 Boly, M., Seth, A. K., Wilke, M., Ingmundson, P., Baars, B., Laureys, S., … Tsuchiya, N. (2013). Consciousness in humans and non-human animals: Recent advances and future directions. Frontiers in Psychology, 4(OCT), 1–20. http://doi.org/10.3389/fpsyg.2013.00625 Measuring consciousness as state Measuring consciousness as state •Clinical measurement based on observation of behavior •Signs ‒Eye opening- to pain, loud voice,tracing motion ‒Complexity of motor responses-flexion/complex signs ‒Brainstem reflexes-pupil, cough ‒Verbal-sounds,words, confusion, normal conversation ‒ •Popular tools: ‒Coma recovery scale ‒Full outline of unresponsiveness ‒ 31 Locked-in syndrome •Jean-Dominique Bauby 32 Obsah obrázku text, osoba, muž, interiér Popis byl vytvořen automaticky Obsah obrázku text, alkohol, jídlo, nápoje Popis byl vytvořen automaticky Measuring consciousness as a state •Neuroimaging – bypass motor output •Active paradigms ‒Tennis paradigm (e.g. Boly, 2007)- imagine playing tennis/walking through a house •Spontaneous brain activity ‒Spectral power-lower delta, higher gamma ‒Activity in default mode network, frontoparietal cortices ‒Impaired frontoparietal connectivity •Response to stimuli ‒TMS-EEG- Perturbational complexity index ‒ ‒ ‒ 33 • 34 TMS-EEG- Perturbational complexity index 35 Gosseries O, Di H, Laureys S, Boly M. Measuring consciousness in severely damaged brains. Annu Rev Neurosci. 2014;37:457-78. Altered states of consciousness • 36 What do we know? • 37 Obsah obrázku exteriér, hmyz, zelená Popis byl vytvořen automaticky Take-away points •Good operational definition is necessary. •Contrastive analysis: create minimally different conditions. •Neural correlates of anything are confounded by pre- and post- activity. •There is no single accepted neural mechanisms of consciousness. • 38 • 39 Obsah obrázku text Popis byl vytvořen automaticky Thank you for your attention! 40