Exam 3 (Lectures Q-X)

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body doubles

- "autoscopic" illusions involve seeing a copy of oneself, or someone posing as oneself - this can be seen with schizophrenia, epilepsy, and migraines - McDonald Critchley describes the experiences of Carl Linnaeus - in 1844, AL Wigan described an extreme case with tragic results

communal minds

- Anita Wooley examined question of how social interaction contributes to task effectiveness - about 2500 people were screened for their ability to do spatial imagery and their skill at registering what would distinguish object properties - the top scoring individuals of each category were then paired and asked to perform a task that required doing both, e.g., navigating a maze and spotting when one encountered the same object more than once - initial testing required that they work in silence - pairs where the good navigator was tasked with navigation and good detail spotter was tasked with spotting details did best - pairs where good navigator was tasked with spotting details and good detail spotter was talked with navigating did worst - but if the pairs were allowed to talk, the latter condition did just as well as the former - what happened is that in the process of talking, they switched roles - EG: some philosophers are discussing the concept that modern minds are communal and are more of a product of the culture than of biology

study on current EEG

- DeVries et al. (2020) - the investigators are sufficiently confident to use an extremely complex task that asks for how activity of the frontal lobes can provide executive control of visual working memory - the findings involve delta/theta oscillations provided by the frontal lobes entraining (controlling) the alpha oscillations of the occipital lobe to prevent intervening stimulus events from disrupting the memory that is needed for making a correct choice - experimental details not important - point is that computational tools make it possible to extract EEG signals that tell us something about how the brain areas are contributing to the mental operations being performed in a complex task

zombie syndrome

- Graham became extremely depressed after his second divorce and tried to end it all by stepping into a bath with a plugged in hairdryer - his attempt failed and he woke up "dead" - doctors and family were unable to convince him that he was alive - he could breathe, walk, speak, but he insisted he was dead - his condition was described by Jules Cotard in 1882, and is known as Cotard's syndrome (sometimes as the walking corpse disorder) - those afflicted think that portions of their bodies have died, been removed, or simply ceased to exist - sometimes it is specific mental faculties that are thought to be missing, e.g., they have become half-wits - Cotard reported on Medmoiselle X, who insisted that she had no name - she said that she used to be called Catherine but didn't want to further discuss how she lost her name - she said that she had no age and never had any parents - when asked about headaches or stomach aches, or other pain, she said "no head, no stomach, no body" - Graham had no interest in food and would likely have starved if the family had not insisted that he eat - he would sit in his mobile home, staring at the wall for hours on end - when he did go out, he would often visit a local graveyard; he said that it just seemed like where he belonged; if family members could not find him, that's where they'd look first - a middle aged woman, screaming and incoherent, was rushed to Karolinska University Hospital in Stockholm - the case files showed a history of kidney failure and she had recently been treated for shingles with an injection of acyclovir - put on dialysis to remove any toxins - an hour later she was able to communicate and asserted that she was dead - after two hours, she wasn't quite sure whether or not she was dead - after four hours of dialysis she told the staff that she wasn't dead anymore, but her left arm wasn't hers - next day all delusions had disappeared - Swedish researchers have found similar cases and now suspect that a combo of kidney failure along with exposure to acyclovir can produce Cotard's syndrome

belladonna alkaloids

- Oliver Sacks tells of his experiences taking drugs during the 60s when he was doing a neuro residency at UCLA, living in a small house in Topanga Canyon - one morning he took a dose of artane, which is a synthetic belladonna alkaloid - for an hour or more, he thought it had not produced any effects, then heard a knock on the door - friends had come for a visit, so he invited them in for breakfast - they talked as he prepared breakfast, them in the living room with him in the kitchen - when he called them to breakfast, he got no response; the living room was empty - he ate all of their food but then heard the roar of a helicopter that was landing near the house - went out to greet his parents from England - but on opening the front door, the lot was empty

neural oscillation

- Singer, 2018 - reviews the many ways that neurons manifest oscillation and the functional benefits of this mechanism - neurons can have intrinsic oscillation, which can provide a "clocking mechanism" for timing motor activity - oscillation can serve as a filter for registering specific frequencies, an example being to register dominant frequency components of speech - separate neuron populations can be synchronized by entrainment of their oscillations, sometimes described as resonance - specific frequencies of oscillation may be involved in learning - for ex, hippocampal theta rhythm appears to enhance long-term potentiation - alpha rhythm may enhance plasticity of cortical circuits - singer's review includes specifics on how individual neurons can interact to provide oscillation circuits

ownership and robots

- Yale researcher Xuan Tan and colleagues are programming their robots to be socially aware, and in particular, to learn the concept of object ownership - the robot learns both from direct instruction and from its own interactive learning - it was instructed not to touch objects that were owned by Tan - a number of colored blocks were put on a table and Tan played only with the red blocks - then the robot was instructed to throw away everything on the table, but when it reached for a red block, Tan stopped it, saying "that's mine" - the robot then cleared the table of all non-red blocks - later, an assistant directed the robot to throw away a red block, and it replied: "I am forbidden to throw it away if it is owned by Tan"

what provides for mind?

- a classic answer is that god has provided humans with unique mental skills, including perception, memory, thought, and consciousness - Greek scholars advanced a number of alternative ideas, but they did not provide much real insight - the major advance came from Descartes, who argued that many of the mental skills of humans and other animals could be based on mechanistic principles

mentalism

- acceptance of paranormal phenomena springs generally from the belief that the mind is not bound by natural law, i.e., is not constrained by physics, chemistry, or physiology - if it is not, it is not unreasonable to think that one mind may know the mind of others (telepathy) or move objects (telekinesis) or know the future (clairvoyance) - those claiming supernatural mental powers have influenced decisions if emperors and kings, as well as providing entertainment even for those who are non-believers - Claude Alexander Conlin claimed to be telepathic, performing under the stage name "The Man Who Knows" - audience members would give him sealed questions, which he answered from the stage; his method for being able to do so was never discovered; he was the highest paid mentalist in the world at the height of his career, earning millions of dollars during his lifetime

computed tomography (CT)

- basic idea is to register how much the tissue blocks the passage of a very narrow x-ray beam - one has the x ray source on one side of the person and the x-ray detector on the other - the first gen device would pass the xray source and detector laterally, collecting data on the density at successive locations along the path - then the process would be repeated at various angles, building up an overall image of the densities within the object - subsequent models improve efficiency by spreading the beam and providing a larger number of detectors

bearings in brain imaging

- brain imaging studies may provide cross-sections in which the brain has been "sliced" in three different planes - some reports will show the brain using coronal images, but most use horizontals - sagittal images are much less common, but the investigators will sometimes provide one that divides the two hemispheres just to show which horizontal slices are being provided

addiction

- complex topic - there is heavy involvement of the reward system that provides exhilaration when we achieve a goal, receive praise, or have a joyful experience - dopamine system appears to be involved, and a deep brain nucleus called the accumbens plays a key role - Kathy, a British citizen and mother of two, was diagnosed with Parkinson's disease at the age of 44 - she was prescribed a dopamine enhancing medication to help treat the disorder - she soon began to experience strange side effects - at first, she compulsively bought lottery tickets - then she began to play poker on the internet even though she did not understand the rules - she shopped impulsively, purchasing items that she didn't need - previously modest in outlook, she developed a strong and uncontrollable libido - bought latex and leather clothing and arranged to meet strangers for sex - she lurched from exhilaration to remorse about this compulsion - her marriage failed - when she finally figured out the cause of the changes, the drug dose was lowered, and the unwanted behaviors disappeared - it is now known that 10-15% of patients taking dopamine enhancing medications will experience changes in emotional/motivational states

Koch on qualia (2018)

- disagrees with some modern philosophers (Daniel Dennett) who argue that it is an illusion/epiphenomenon - but if the conscious experience is not an epiphenomenon, what is its nature? - David Chalmers sees it as a separate state of nature, like gravity or electromagnetic energy - EG: this is related to the views of what I call "quantum mystics"

magnetic resonance imaging

- equipment again similar to CT and PET scanners - but the donut that one lies within is a superconducting magnet that generates a very intense magnetic field - magnetic field does not harm biological tissue - various molecules, e.g., water, manifest a tiny amount of magnetism - the intense magnetic field causes these molecules to line up - a narrow plane of radio waves is moved across the object disrupting alignment in that plane - the water molecules absorb the radio waves, disrupting the alignment - once the band passes the molecules emit a radio signal as they re-align to the global magnetic field, picked up by antennae that surround the chamber, and the time this takes reflects the density of the medium in which the molecules reside - one can cross compute the signals that are generated to derive a 2D image of tissue density at various planes - various kinds of trauma, disease, or pathogen can affect the density of brain tissue, so MRI has proven to be exceptionally valuable for providing effective diagnosis of all manner of cognitive impairment

coma study: Peran et al (2020)

- evaluated 43 coma patients on admission to the hospital and at three months using fMRI and structural MRI brain imaging - analysis focused on the medial prefrontal cortex, the posteromedial cortex, and the cingulum based on proposals that these brain structures are central to the "global neural workspace" and may provide the neural basis for conscious awareness - the cingulum is a fiber tract that connects medial prefrontal cortex to posteromedial cortex - this article finds that degree of damage to this linkage predicts the prospects for recovery from coma irrespective of the brain trauma that produced the damage - dehaene's global neural workspace in image

coma study: Zheng et al (2020)

- examined whether high definition transcortical direct current stimulation (HD-tDCS) administered several times over a two week period would modify the brain activity of patients who were partially or totally comatose - location of it is illustrated in the image - HD-tDCS is provided through a small cluster of electrodes - they administered the stimulation to 15 patients with unresponsive wakefulness syndrome and 20 with minimally conscious states - the treatment was found to be effective in increasing brain activity in the latter group, but not the former - mainly modifying EEG activity in the beta and gamma frequency ranges - in the frequency heat maps the dark red indicates the greatest activity - one can see that the unresponsive comatose patients mainly have activity in the alpha frequency range, reflecting a minimally active cortex - those minimally conscious has more high frequency activity

Koch, C. (2004) The Quest for Consciousness

- front of the brain is mainly designed for action, with the rear being mainly for perception - activity may bounce back and forth - there are many unconscious neural operations, especially in the spinal cord and cerebellum - circuits in the cerebellum are mostly parallel, pass through fine tuning of motor commands, with none of the reverberatory cross linked interaction that one sees in cortex - critical neuronal interactions involve "coalitions" - basically what Hebb described as "cell assemblies" - attention is a conscious operation that brings specific coalitions into a dominant state - they argued that high frequency EEG, e.g., 30 Hz and above provides a special marker for conscious activity - they especially emphasize synchrony of firing as a basis for creating coordination among brain regions - so their concept of how to achieve a "unified" conscious experience is to get the various modules synchronized - the circuits mediating the high frequency EEG are providing that synchronization --> synchronized oscillations that couple neural activities

drugs 2

- if free will is generated by something other than biological mechanisms, why would drugs modify it? - we can envision how drugs can modify the balance of neuronal activity, but why would a non physical mind be affected? - if the mind is subject to chemical pressures, is it not part of the physical world? - if the mind is part of the physical world, on what basis would it be exempt from the physical laws? - what is the evidence that the mind is exempt from physical laws? - EG: I don't think that qualia should be viewed as an illusion; that term simply refers to the mental model that one has built from sensory input; the mental state is provided by neuronal activity that the stimulus has generated - but the concept of free will proposes that some mental states are not based on neuronal activity - it says that there are choices that are not determined by the interaction of neurons - if one believes that all mental states are based on neuronal activity, then one must conclude that the sense of having free will is an illusion

Poldrack (2018) study on use of blood response to measure brain activity

- in 1877, Michele Bertino was standing next to a bell tower in a small village when a brick dropped 40 ft and hit him in the head - he recovered from the blow but was left with a hole in his skull - Prof Angelo Mosso decided to monitor the size of the pulses from his heartbeat that pressed on the scalp covering the hole - he recorded an increase in the amplitude of the pulsations when Bertino heard ringing of the local church bell, for he normally would say his Hail Mary prayer on hearing the bell - these findings were replicated by Field & Inman (2014) who showed that the weight of the head increases from the increased blood flow when a person is provided with an audio/visual stimulus

synchrony of neuron populations

- intracranial subdural electrodes provided EEG signals in epileptic patients to monitor interaction of cortical areas in the temporal lobe as patients retrieved memories - the activity in "multisensory association cortex" (yellow) was synchronized with activity in medial temporal cortex (blue area) when memories (word pairs) were being retrieved - there was no coupling of activity on incorrect trials or when the memories were first being learned

quantum mystics etc.

- most physicists acknowledge that trying to extend the superposition concept (and observation as a causal factor) to the larger world of real objects is not reasonable; but there are some who are - these theorists, often physicists, deny a number of classic concepts that define the nature of reality, and propose that consciousness can determine that reality - Amit Goswami - quantum mystics claim that time, distance, and causation are moot issues, and human observation transcends all such limits - quantum brains: Roger Penrose and Stuart Hameroff; returning (perhaps only a little) to reality, some physicists are proposing that the brain may use quantum mechanisms for computing and/pr storing info; claim that microtubules provide for quantum computing - quantum brain project: Matthew Fisher; although most efforts to implement quantum computing require using ultrasound and ultrapure atomic conditions, Fisher believes that quantum memory storage may be provided in the wet and warm cellular soup; he argues that the nuclear spin of certain molecules is linked in superposition to form the "qubits" required for quantum computing - Murray Gell-Mann: "quantum flapdoodle" - EG: the quest for quantum mechanisms is a pipe dream; the cellular soup will not provide for superposition or any other exotic quantum phenomena; so let's assume that mind is being provided by normal physical and chemical mechanisms

neurotransmitters

- most psychoactive drugs have some relation to brain chemicals, especially those that are involved in the transmission of info and control of emotions - so one should at least hear of two major categories of neurochemical activity and see some examples - NTs are released at synapses and provide for transmission of info or influence from a neuron to a target (usually another neuron) - ACh - NE - DA - 5-HT - GABA - glutamine - it is generally believed that most of the psychoactive drugs mimic or otherwise influence synaptic transmission - the net effect can be from action at many different brain sites, sometimes producing opposite effects at a different sites

bionics

- neural prosthetics and brain manipulation - cochlear implants - visual prosthesis - electromechanical skin sensors - prosthetic skin cues - olfactory prosthesis - neuronal prosthesis

further development of event related potentials

- one can average across many epochs of EEG, each epoch being triggered by a specific event (most often presentation of a stim) - and making use of computer processing of many recording sites, one can provide "heat maps" of which location on the upper cortex is providing a particular signal component - one can also show how the source moves from one location to another over time

cocaine and amphetamines

- one can have hallucinations with use of cocaine or amphetamines, which stimulate the reward system that is mediated by dopamine transmission - mescaline, peyote, psilocybin, and LSD are thought to influence the serotonin transmitter system - morning glory seeds have a hallucinogenic agent that acts like LSD

magnetoencephalography (MEG)

- the aligned apical dendrites of cortical cels can generate enough combined current flow to produce a weak magnetic signal - the location of the signal can be registered similarly to an fMRI - like EEG, the response is on the same time scale as neuronal processing of info, i.e., within 10s of milliseconds - but unlike EEG, there is better info about which brain region was activated - Marzetti & associates argue that MEG is especially useful to documenting the synchronized activity of neuron populations by registering the phase coupling of their oscillations - as an ex, they show synchronized activity of the frontal eye fields (for voluntary control of eye scans) with activity of vision processing at the junction of occipital and parietal lobe - these sites also manifest linkage of oscillation across the range of frequencies - this kind of measure should provide a means to test some of the assertions made by Singer on the role of neuronal oscillations

positron emission tomography (PET)

- the equipment doesn't look much different from a CT scanner, but it is functionally much different - a cyclotron is used to generate a fast-decaying radioactive tracer, which can be attached to a molecule that will "tag" diseased brain tissue - so the molecule becomes concentrated at the location of the disease, e.g., cancer - one can also tag metabolic factors that are not disease related - the radioactive tracers decay, each producing a positron and an electron that travel in opposite directions - the housing that surrounds the head detects these particles and one can calculate the source location of each pair - it is therefore possible to determine where the tracer has greatest density, which can indicate the location of diseased tissue - PET scans have proven to be especially useful for evaluation of disease states that have metabolic markers - ex: alzheimer's - EG: pseudocolor has become increasingly prevalent in brain imaging; differentials of brightness can convey an equivalent amount of info about the state of the tissue, but color is much more dramatic

mescaline

- the first published account on mescaline effects was in the British Medical Journal in 1896 - description of hallucinations inside - Henri Micheau (French poet)

cochlear implants

- the frequency components of the sound vibrate the basilar membrane the most at specific locations along its length - electrode array in the cochlea stimulates different locations along the basilar membrane depending on the frequencies provided by the sound - normally they would stimulate hair cells, which relay the frequency components to adjacent neurons - if the hair cells are killed by toxins, fever, high intensity sound, or other factors, the neurons can still be activated with electrical stimulation - the cochlear implant inserts a ribbon that places electrodes along the length of the basilar membrane - a microphone captures the sound, a microcomputer extracts the frequency components, and each frequency stimulates a specific location along the length of the basilar membrane are stimulated to activate local auditory neurons

dealing with ignorance (robots)

- the little delivery bots have received thousands of instructions on how to deal with city traffic - it comes to the cross walk, has a walk signal, and sees no cars coming from either direction - but now something happens that is not within the instruction set: the scream of a siren fills the air - the bot has been trained to look for what humans are doing and follow their lead

haunted minds

- the role of anguish and guilt for generating hallucinations and delusions is a cornerstone of literature - Hamlet's murdered father appears to tell him how he was murdered and must be avenged - when Macbeth is plotting the murder of King Duncan, he sees a dagger in midair - later he hallucinates Banquo's ghost while his mother sees the king's blood on her hands, which no amount of washing will erase - grief can be a source of hallucinations - during the 1800s, doctors became increasingly aware that all manner of physiological and psychological trauma as well as brain damage could produce anomalous mental states - rather than seeing this as the work of demons, they began to attribute the symptoms to impairment of brain mechanisms

qualia

- the subjective experience of sensory info, e.g., perceiving "redness" from light of a certain wavelength - can't accurately describe or measure - ex: mary's room (knowledge of an experience vs the experience itself) - philosophers have long debated whether qualia represent a special state other than complex neuronal activities - Dennett says that qualia do not and cannot exist as special states and are essentially illusions - EG: epiphenomena - some argue that qualia are epiphemonena - this is an event or state that has no causal relationship to what brought it about - a computer can process billions of bits of info, do stat analysis, store info, etc.

diffusion tensor imaging

- this method also uses the MRI machine but with far higher magnetic field strength - rather than measure blood flow and use, it measures the ability to move water within nerve pathways, and therefore maps the fiber tracts - this can be done selectively, and then color-coded to specify differential connectivity of the brain - this has proven to be especially useful for clarifying the functional interactions among brain areas

personality and mood: genetic factors

- thomson describes amazing similarities in the lives of Jim Lewis and Jim Springer, identical twins that were separated at birth and reunited 39 years later - EG: generally, personality factors are about 50% heritable - things they had in common: tension headaches, nail biting, work in law enforcement, enjoy woodworking, smoke salem cigarettes, drive same model car, holiday at the same FL beach, each married women named Linda, each re married women named Betty, sons named James Alan Lewis and James Alan Springer, each call the family dog by the same name, Toy

EG: the human mind has great facility for modifying what component of a scene is pertinent to the current need

- what info is useful? - ex from machine vision project: - the neural network was shown 500,000 random images, with the critical content of each being identified - one of them was the image of a bowl with mushrooms - the network was then shown the image of the bowl with other things in it and was asked what it is; it declared it was a bowl of mushrooms (none of us would've made that mistake) - why did the neural network fail to make that identification? - hypothesis 1: it had not previously been presented with a bowl of light brown cookies/cakes; EG: doubtful that any of us had seen this confection either, but we knew that the contents were not mushrooms - hypothesis 2: the neural network was not able to separate out image elements in a way that provided labeling of each component of the image; EG: that's part of it, the neural network connectivity is registering not only the mushrooms but also the bowl and even background components that are completely irrelevant; they are part of which image it chose as being most relevant to the current match being requested; human vision can see global features as well as local ones and can record them separately; so the initial training for labeling the image would have specified that one was attaching the mushroom label to the contents (not the bowl or any other image element); and it would see each component as distinct from the collection - hypothesis 3: the neural network has not been provided with a "don't know" option; EG: true, a common mistake in programming recognition algorithms is to require a best match, which ensures some number mistaken identifications; a more realistic and human option would be to have a higher demand for a more certain match; being able to determine that one doesn't know the answer can trigger mechanisms that compel a search for more info - hypothesis 4: the neural network does not have any biological imperaitve; EG: indeed, human behavior is generally motivated; there are needs to be met, goals to be achieved; on being present with a new circumstance, one can rightly ask whether it contains anything relevant to those needs and goals; one will try to determine what is the most critical info; the neural network was provided with none of these tools; it manifests "artificial ignorance" rather than artificial intelligence

transmagnetic stimulation

- when placed over V1, it generates phosphenes, e.g., flashes of light - V4 is known to be involved in the perception of color, and damage to this area can leave a person with normal vision but without any color - TMS stimulation of this area produces color visualizations - V5 (MT) is known to be involved in perception of motion - individual neurons in this area discriminate direction of motion of moving dots with the same sensitivity as human judgments - TMS stim of V5 produces the perception of visual motion

quantum mechanics

- while we now acknowledge that we cannot predict all potential interactions of complex systems, that is is near impossible to unravel cause and effect for many of the interactions, these systems are still intrinsically operating on the basis of physical laws - they are "deterministic" - but at the beginning of the 20th century brought a major challenge to this concept, with the development of "quantum mechanics" - key concept: heisenberg's uncertainty principle - one can't simultaneously know the exact momentum of a particle and also its position - measuring one with precision eliminates the possibility of measuring the other with precision (thus denying classical determinism) - this might seem no more critical than the finding that most physical systems are chaotic; but the departure went farther than mere ability to specify the variables - another argument against determinism: dual nature of particles/waves providing ambiguous states - various phenomena in quantum mechaics are based on wave properties of matter and energy - some conditions may provide a quantum of energy with particle-like behavior, allowing one to measure the location of the particle - other conditions provide for wave-like behavior, wherein the energy is spread out through space - which property one can measure depends on what observation method is used - Einstein and Schrodinger thought deterministic principles would eventually be discovered - but many physicists took the position that the true state of nature is simply unknowable - that quantum phenomena could be random - Copenhagen convention's "role of observation" - if the outcome can vary from trial to trial one must specify it as a probability; one cannot say what will be the outcome on a given trial, only what are the odds of getting a given outcome - but at a convention in Copenhagen, some of the quantum physicists adopted the view that prior to observation, all the alternative possible states were simultaneously present, which they described as "superposition" - further, they asserted that the alternatives "collapsed" to a single state when the measurement was taken - as strange as it sounds, they were claiming that the observation itself was a critical causal event

conscious meter

- Christof Koch, working with Giulio Tononi, has described a method for eliciting brain activity that may provide a useful diagnostic tool - one uses TMS to "zap" the brain - if widespread EEG activation can be elicited, described as "zip" -- there may be some potential for eventual conscious recovery - early clinical testing suggests it may prove to be a useful diagnostic tool - Demertzi et al (2019) developed diagnostic criteria completely on the basis of the complexity of the EEG activity itself, building essentially on Dehaene's concepts that stimuli have a very local influence if they are not consciously perceived, and consciousness is reflected in the widespread activation of brain sites

memory

- George Koltanowski took up chess at age 14, and was Bulgaria's chess champion three years later; he set a world record in 1937, playing 34 simultaneous games blindfolded, winning 24 and with the remaining 10 matches a draw - Alex Mullen was a med student who read a book about how to train your memory; two years later he won first place in the 2015 World Memory Championship; this contest provides a number of memory challenges, but the finale requires that you memorize the order of a deck of cards, precisely, in the shortest time possible (did so in 21.5 seconds) - Thomson claims that individuals who demonstrate this kind of skill do not have exceptional memories, per se, but are implementing the method that is described in Sherlock Holmes novels as the "mind palace" - related concept is to make bizarre associations, e.g. improbable juxtapositions of odd items or events with the thing to be remembered; one card memorizer gave the example that if a set of three cards happens to be the 4 of hearts, 9 of hearts, and 8 of clubs, he would immediately visualize Sherlock Holmes playing a guitar and eating a burger - there are, however, individuals who have an amazing ability to remember events in their life, day by day, without using this kind of "mind palace" technique - in 2001, Jill Price sent an email to the psychologist James McGaugh, claiming to have exceptional recall of each day in her life - once these findings were published, McGaugh was flooded with claims of exceptional memory; his team tested them all and was able to locate five other individuals with this talent; other memory abilities were relatively normal; what he did note was an excessive tendency to ruminate the events of each day and repeatedly recall events of previous days; it seemed somewhat like OCD, and he suggested that it might be a specific form of that mental condition - brain scans found small differences in 9 regions, including enlargement of the caudate and putamen, structures that have been implicated in OCD - in image: putamen (purple), caudate (orange), showing connection to the amygdala

the subconscious

- Koch talks about "zombie" activities of the brain - these mediating semi-automatic behaviors such as driving while thinking of your plans for the day or a musician playing a well-practiced sonata - but with respect to the subconscious, Dehaene does far more than most theorists to distinguish conscious from subconscious processing - Kokch recaps some work on providing electrophysiological markers for conscious state that may help determine if a brain damaged and non responsive patient is still conscious - he cites earlier work with Tononi wherein they proposed a concept called integrated info theory - posits that it is the interconnectedness of all the sensory events that provides for subjective experience - the more complex the confluence of stimuli being synthesized, the richer the experience - he says that any stimulation of the brain that is running on a computer cannot provide sentience, any more than a model of physical events in a black hole can create the gravitational forces that the black hole generates; depth of experience based on simultaneous confluence of sensory events, stimulation not being the actual experience, two diff concepts

synesthesia

- Rubin Diaz Caviedez sees a person's aura - red = he likes them - green = disliked - variety of factors affects the color, including the tone of their voice of personality - can be ephemeral elements (translucence, shimmering, sparkling) - Rubin's synesthesia is not just for his perception of people; he sees all manner of objects as having colors - synesthesia is most commonly seen with attribution of colors to letters and numbers - but sounds can have associated colors, or vice versa, and words can evoke specific flavors - has a heritable component and is commonly assumed to involve miswiring of the brain, i.e., the sensory systems that are normally kept separate have been anatomically linked - but this doesn't explain why hallucinogenic drugs can produce synesthesia, or that it can be suppressed by antidepressants - further, training trials can generate synesthesia, and it can reverse quickly once the training is discontinued - one odd aspect of Rubin's condition is that he is "colorblind", has poor discrimination of red vs green - as a small child, he once painted a pictur eof a horse and colored it green; the teacher took this as an indication that he was creative, with great potential to be a creative artist - Ramachandran (UCSD) had a student who was colorblind and also generated color synesthesia; he called the ones that he created "martian colors" - thomson makes reference to the fact that the cortex (V4) interprets color signals and implies that this area might be manufacturing the colors (image) - color wheel: non spectral purples - EG: your brain manufactures your perception of purple colors; no single wavelength of light in the spectrum will produce the perception of purple; spectrum ranges from red-violet, and a single wavelength within the spectrum can produce the perception of the colors around most of the color wheel; but one must have a mixture of two wavelengths, e.g., red plus blue, to produce a purple color like magenta; so your brain is manufacturing a color that does not exist in the spectrum

subliminal perception

- dehaene, 2014 - cites a widely reported 1957 study where the words "Drink Coca Cola" was briefly flashed on a screen in the middle of a movie, and soft drink sales went up - this excited the advertising community and the use of "subliminal cues" were studied and discussed for many years after - the supposed study never took place but was a joke perpetrated by James Vicary - up until 1990 or so, it was assumed that all conscious activity was cortical and any nonconscious perception or behavior was mediated by subcortical mechanisms - dehaene provides subliminal priming in a reaction time task and demonstrates that an unseen prime word will speed response to subsequent presentation of the word - his point is that the subliminal cue is processed by the language system even though it was not consciously perceived - dehaene claims that subconscious mechanisms process all possible meanings of a word, producing cross-context priming - he suggests that the subconscious system calculates all prior probabilities, meaning that it modifies the weights of alternative cognitive associations - dehaene provides evidence for subcortical mechanisms of emotional response to subliminal cues - he examined electrical responses from deep electrodes implanted into the amygdala of patients - emotionally charged words produced activation, whereas neutral words did not - dehaene has another interesting way of testing what will elicit cortical activation that signals conscious awareness in humans - a sequence of sounds is provided: beep beep beep or beep beep boop - the signatures of alerting are not generated if the last sound matches those that came before, but he does get cortical arousal if the last sound differs (monkeys show activation) - one can get activation also if the sequence normally contains the boop as the last sound, but instead one hears a beep - dehaene describes the activation of consciousness as "ignition" - the fMRI shows where there is activation with conscious ignition - he provided further work using high resolution event related potentials (from EEG) to show the timing of the activation - the brain is being viewed from above, and the dark regions of each image shows major brain activity - the upper row of brain maps shows that only the occipital lobe is activated if the word is not seen - but there is widespread "ignition" of activity if it is consciously perceived (lower array of brain maps) - Crick and Koch claim that one sees especially high frequencies of EEG in cortical areas that are doing conscious processing of info - dehaene finds support for this where masking was used to preclude perception of a target face - face targets elicited gamma frequencies, i.e., those at or above 30 Hz, far more with display conditions that allow the face to be consciously perceived - EG: he and others like to use the word "synchrony", implying millisecond level timing, for which there is minimal support - dehaene proposes that the wide spread activation of brain regions is conveyed by large pyramidal cells that provide long axons - he suggests that the smaller cells in a given region have a "sensory" function - EG: the general concept isn't unreasonable, but it may not be optimal to describe the role of the smaller cells as being "sensory" - all manner of local processing is being accomplished, and in some regions this activity will be for programming of motor sequences or other non-sensory functions

drugs

- in the late 1800s, a number of addictive drugs were being commercially promoted for treatment of various sources of pain, or just to lift one's energy level - and physicians became interested in describing abnormalities of perception, memory, and cognition that some of these drugs produced - mind altering drugs from distant lands became available in europe, and many young artists and writers experimented with drugs - some provided detailed descriptions of their experiences

neuropeptides

- special class of neurotransmitters that are especially able to provide targeted action - the peptide is a string of amino acid molecules that can function like a key that will only bind with a specifically designed receptor - these are especially known for their role in perceptions of pleasure and pain - these may also be released by the pituitary gland to act at distant targets in the body - oxytocin - endorphins (of which enkephalins are a subclass)

narcolepsy and nightmares

- term coined by Jean Baptise Edouard Gelineau in the late 1870s - generally includes both hallucinations and paralysis - these patients may have dozens or even hundreds a day - the hallucinations appear to be much the same as for the hypnagogic state - extreme emotion can trigger them, including laughter - nightmares commonly will involve an extreme sense of dread, and the sense of pressure on the chest that makes it hard to breathe - the dream imagery will commonly be a source of fear as well - "The Nightmare" by Henry Fuseli in 1781

brain imaging

- the biggest technical change came in the last quarter of the 20th century, this being development of brain imaging methods - x rays had been used for many decades to show damage to the skull - it could vaguely register major changes in density of the brain that could come from stroke or tumor - but computed tomography provided far better definition of soft-tissue damage, making it possible to see which brain regions were affected

electromechanical skin sensors

- the development of tactile sensors in artificial skin is critical in robotics, where feedback is needed to allow a gentle grip, or sense differentials of pressure on the feet for dealing with uneven landscape

metaphors for consciousness

- theater stage - spotlight

diffusion tensor tractography

- used by Jang & Kwon (2020) - an MRI method that allows one to follow fiber tracks, to evaluate patients who were unconscious due to traumatic brain damage - these patients had greater disruption of connections from the ascending reticular activation system than did patients who remained conscious after traumatic brain damage - so after being ignored or dismissed for the last half century, it appears that the original hypothesis of Moruzzi & Magoun may be credible - but gaining support for the concept required major advances in brain imaging methods

classic EEG (end of 20th century)

- was thought that EEG would provide a window into the mind - recordings were taken from 6-12 electrodes, each providing an erratic undulating trace like one of those shown - investigators and clinicians thought the attributes of a given trace would reflect the mental state of the person - when combined with task requirements, the hope was that one could infer how neurons were providing for specific skills

EEG recording methods improved near the end of the 20th century

- EEG began with just a few recording locations, and there was substantial uncertainty about what location was generating the signal - computers made it possible to process the signals being generated by a large number of leads, which improved the ability to say what part of the brain was generating the electrical activity

Uri Geller (mentalism)

- Israeli-British illusionist, magician, and self proclaimed psychic, known especially for his demonstrations of spoon bending, describing hidden drawings, and making watches stop or run faster - he claimed that his paranormal abilities were given to him by aliens; under hypnosis he claimed that he'd been sent to earth by ETs in a spaceship from 53,000 lightyears away - several prominent magicians discussed his spoon bending trick as something that could be accomplished by sleight of hand and other methods of misdirection - the Nobel laureate Richard Feynman, who was an amateur magician, said that he was unable to bend a spoon for him and his son; watchmakers said that he made stopped watches run again by moving them around - in 1992, Geller was asked t investigate the kidnapping of Hungarian model Helga Farkas - he predicted that she would be found in good health, but she was never found and is believed to have been murdered - in march 2019 he wrote a letter to British PM Theresa May, stating that he would telepathically prevent her from leading Britain out of the EU

marijuana

- Jacques Joseph Moreau (Paris, 1840, when the use of hashish in Paris was very fashionable) - hashish (cannabis resin extracted from hemp plants) was introduced to Europe from Algeria in the mid 1800s, and by 1890 they were toying with mescaline and peyote - William James

empathy

- Joel Salinas has synesthesia (letters are colored and his image of people includes colored letters that reflect his assessment of their personality) - but this isn't what is unusual: he also feels the sensations that others are experiencing, e.g., a touch on the arm, the pain of a sprained ankle - he registers what emotions they are experiencing; can see a facial expression (even one producing micro movements) and immediately senses what they are feeling - this condition is called "mirror-touch synesthesia" and the dominant hypothesis is that it is produced by hyperactive "mirror neurons" - the first report about these neurons was by Giacomo Rizzolatti in 1992 - recording from pre motor cortex of macaques, they found cells that fire either when the monkey grasped a peanut and when it saw another monkey grasp the peanut - as one would expect, subsequent work has suggested a more complex interaction with neurons in the parietal and temporal lobes, yielding what might be called a "mirror-neuron system" - Sarah Jayne Blakemore scanned the brain of a woman who had mirror-touch synesthesia and claimed that this system was more active than normal - EG: be aware that these inferences are controversial, with a number of investigators arguing that the mirror-neuron system does not exist in humans; it is not clear whether they are also denying the existence of a mirror-touch syndrome

LSD

- LSD25 was synthesized by a Swiss chemist, Albert Hofmann, in 1938 - major distortions of perception are color enhancement, size changes, modified depth effects, enhanced or created 3D, e.g., seeing flat pictures in 3D

lycanthropy

- Matar, who lives in Abu Dhabi, transforms into a tiger - that is his self image when he has been off his meds and suffers a schizophrenic episode - he feels the hair on his body stand up, claws growing from his hands, and has an urge to attack those who are nearby - he often sees them as lions about to attack him, and he needs to attack first in self defense - he sees himself in the mirror as a tiger, often with a lion behind biting his neck

emergent properties

- Newsome argues for consciousness as an "emergent property" of complex systems - for instance, the chemistry of hydrogen and oxygen does not provide any insight into the properties of a water molecule - and the chemistry of a water molecule does not provide insight into what are the various forms of water - vapor, liquid, frozen - and there are countless variations in how each form manifests itself as part of the environment -- cloud formations, rivers and oceans, glaciers and Colorado powder - the development of even a single celled organism could not be predicted based on knowing the constituent parts - the assemblage provides unique and unexpected attributes - Newsome's point is that any very complex system has manifestations that are far from predictable - an interconnected system as complex as the brain cannot be understood using classic cause and effect concepts - each of the myriad possible interactions can seem a total mystery

free will?

- Newsome thinks everything is predetermined - perhaps some not quite remembered memory of having suffered a mild bout of food poisoning after eating at Seafood Heaven has tipped the scales for the decision - if choice is illusory, can anyone be held responsible for their action? - our legal system is predicated on the concept of responsibility for one's actions

the 60s

- Peter Max - the Haight Ashbury District in San Fran came to symbolize the movement - but the mood swept across cultural centers in much of the western world - Timothy Leary, clinical psychologist at Harvard, conducted studies on the effects of LSD under the Harvard Psilocybin Project when it was still legal - he was later fired for questions about the legitimacy and ethics of the research, including taking the drugs himself and pressuring the students to do so - Carlos Castaneda wrote a series of books describing the psychedelic effects of peyote and other drugs that were used by shamans in Mezzo-American cultures - many other artists and writers in this period were advocating the use of mind altering drugs

olfactory prosthesis

- Prof Richard Costanzo at Virginia Commonwealth is working on an olfactory stimulator similar in concept to a cochlear implant - olfactory neurons have substantial ability to regenerate, but anosmia can develop in some cases - the anatomy of the olfactory bulb is near optimal for delivering electrical stimuli - there is a mitral neuron dedicated to registering each elemental odor and they can be stimulated with an array of electrodes (like a micro sized hairbrush) - one registers elemental odor combinations with electronic sensors and then delivers the pattern that was detected to a set of electrodes; different electrodes depending on the mixture - there are about 350-400 molecular odor receptors in humans, each activating only one of the mitral cells in the bulb - a complex odor will stimulate several of these mitral cells - an electrode array can generate a unique pattern as well - EG: this illustration (image) is not fully accurate but is close enough

Nina Kulagina (mentalism)

- Russian woman who claimed to have psychic powers, especially psychokinesis - after WWII silent films of her abilities were made by Soviet authorities in which she moved objects on a table without touching them - soviet scientists, including two Nobel laureates, vouched for the validity of the effects - these included having her separate broken eggs that were underwater, moving apart the yoke and white of the eggs, while they monitored her brain waves - to determine whether her brain waves were producing the results, she demonstrated the ability to remove a marked matchstick from a pule of matches, all under a glass dome, while she herself was within a metal cage - in a Leningrad lab in 1970, the scientists Sergevev monitored as she used her mental energy to modify the beating of a frog's heart that was floating in a beaker - she apparently made it beat faster, then slower, and then with extreme focus of thought, stopped it from beating - skeptics objected about the potential use of mirrors, fine threads, magnets, and other devices - not with standing the critics, there was never any firm evidence of deception

is belief in psychic powers a psychiatric condition?

- Scimeca and associates (2015) evaluated 31 individuals who reported common experience of extrasensory perceptions (telepathy, clairvoyance, or precognition) compared with 31 individuals who had not - they assessed self reported trauma history using the Childhood Trauma questionnaire as well as traumatic signs provide from the Rorschach Traumatic Content Index - the participants also completed an Anomalous Experience Inventory, an MMPI, a Dissociative Experience Scale, and the Revised Paranormal Belief Scale - those reporting experience of ESP phenomena had higher levels of emotional abuse, sexual abuse, emotional neglect, physical neglect, and traumatic intrusions - these findings are consistent with a number of cited studies that find a strong connection between belief in paranormal phenomena and severe sexual or other traumatic childhood abuse

mental maps

- Sharon is Wonder Woman; at age 15 she was playing in the backyard, realized she was lost - she hid the condition from friends and family for 25 years before finally telling her brother, and with his urging, sought med attention; no brain abnormalities were found, so several doctors suggested a psychiatric condition, including split personality - she eventually came to the attention of Guiseppe Iaria, who has specialized in the study of navigational deficits, and has located more than 600 individuals who manifest various degrees of this condition - sharon's sense of being "lost" includes how to navigate the hall to get to the bathroom, or which drawer in the kitchen has the silverware - our ability to navigate the world depends on our memory of spatial cues - landmarks along with a mapping of their relationships - the work on "place cells" of the hippocampus and "grid cells" of the entorhinal cortex suggest that these regions contribute to what can be described as "mental GPS" - brain scans and other evidence provided by Prof Iaria suggest that the mental GPS system involves communication between the entorhinal/hippocampal complex and the frontal lobes - one can have impairment of the GPS function if communication between these areas is not normal - rapid turns could trigger Sharon's symptoms - at some point she discovered that she could physically spin in a direction that provided a correction of her mental GPS system - so if she became disoriented, she would go into the bathroom, or a closet, or a dressing room, and spin, resetting the system os that she again recognized where she was in relation to the rest of the world - she describes this as being Wonder Woman

alien body parts

- V. Ramachandran (UCSD) describes a case of a 29 year old man who expressed a desire to amputate his right leg - he described his leg as "over complete" and had felt so since the age of 12, and wanted the excess gone - he eventually froze the leg with dry ice, forcing surgeons to perform the amputation that he desired - Paul McGeoch (Berkeley) had four such cases - he recorded brain activation from being touched in the region that seemed alien vs a region where they felt the touch as normal - touching the alien region failed to produce activation of the sensory homunculus - in other words, if that area is not registering the touch, then it appears that the brain is inferring that the region is not part of one's self - Laura Case (Berkeley) tested 8 transgender people who were genetically female but identified as males, compared to 8 controls - they were all touched on the hand and on the breast while brain activation was recorded - the transgender people showed much lower activation difference, i.e., touching the breast did not produce the expected amount of brain activation - it is not clear whether this was a predisposing condition that induced a desire to change gender, or if a lifetime of rejecting identity as a female produced a reduction in responsiveness

mentalism: support from psychologists

- William James believed in parapsychology, as did Gustav Fechner who is best known for inventing the experimentally rigorous field of psychophysics - in the 1930s, JB Rhine of Duke and his wife Louisa Rhine conducted investigations into extrasensory perception (ESP) - she focused on reported cases and he developed "rigorous" experimental tests - Rhine tested for telepathic abilities with a deck of cards that displayed five unique symbols - five cards with a given symbol to provide a deck of 25 cards - after shuffling the deck, a "sender" would look at each card and a "receiver" would guess which card had been observed - Rhine used elementary stats and claimed that the guesses were more often correct than would be expected by chance - to test clairvoyance the "receiver" would guess the successive cards of the deck; later work used dice to test for telekinesis - there were numerous reports by other investigators who could not replicate Rhine's work or otherwise find support for psychic powers - nonetheless, Rhine created the Journal of Parapsychology and continued to publish claims of parapsychological effects for another 60 years - he received external funding from Alfred P. Sloan foundation, from Chester Carlson (inventor of xerography), and from the Office of Naval Research, the US Army, and the Rockefeller foundation - most of the US governmental funding came after WWII but as late as the 1980s there was support from the Natl Research Council - as recently as 2011, Darl Bem and associates have argued that one cannot yet rule out the existence of precognition and premonition (advanced knowledge of things to come) - however, most experimental psychologists emphasize doing careful experiments that control for subtle cues, account for bias, and employ effective statistical tests for strength of effect - when these methods are implemented, the general finding is that the psychic powers evaporate, and choices or outcomes fall to chance

Erik Hanussen (mentalism)

- although Hanussen claimed to be a Danish aristocrat, he was in fact a Moravian Jew - after WWI he performed a mind reading and hypnosis act in Berlin, which was frequented by the German military - he supported the Nazis in spite of his Jewish ancestry (an open secret) - stories about meetings with Hitler, which included an encounter wherein he taught Hitler about the use of gestures and dramatic pauses that could influence crowds - to demonstrate his clairvoyance, he predicted the Reichstag fire (an arson attack on the German parliament building) that made it possible for Hitler to seize absolute power in 1933 - Hanussen published a popular biweekly tabloid that included astrological predictions and used the profits to purchase a mansion that became known as "The Palace of the Occult" - guests would sit around large tables, seance-like, and he would dramatically prophesize future events for each of them - after predicting the Reichstag fire, he was assassinated, likely by Hermann Goring and Joseph Goebbels, as a potential competitor for the attention of der Fuhrer

personality and mood: Tommy McHugh

- bad boy from an early age - grew up in a poor Irish family with brothers that were in and out of prison on a regular basis - was subject to dark bouts of depression and bursts of temper, and often used hard drugs, including heroin - he suffered from headaches and was often found with a belt wrapped around his head, presumably trying to pressure away the pain - one day, while sitting on the toilet, he felt something like an explosion in his head - a vessel had burst (subarachnoid hemorrhage) - days later, when he woke up in the hospital, he was suddenly well tempered and optimistic - as he recovered further, Tommy began to paint - first on canvases and then walls; he painted his doors, tables, cabinets; once having covered all that he could find, he started again, painting over what he had done previously - would've painted 24 hours a day if not implored to eat and sleep - creative compulsion appears to be some form of disinhibition of brain systems that normally exert control over our impulses - Jon Sarkin, a chiropractor, also suffered a brain hemorrhage that produced a compulsion to paint all the time - he sold his practice and now is a full time artist whose work sells for upwards of $10,000

ecstasy or agony?

- beginning in the 1970s, psychiatrists prescribed MDMA as a supplement to psychoanalysis because it induced altered consciousness accompanied by increased awareness of the senses - it subsequently became popular as a recreational drug, ecstasy - by 2001, 9.2% of high school seniors reported having used ecstasy and there were over 4,000 emergency room visits due to use of it - at that time it is estimated that 750,000 tablets were being consumed in NY and NJ every weekend - the appeal is that a standard oral dose of 100 mg produces heightened pleasure and a boost in self confidence, manifested as extraversion and manic behavior - effects peak in 15-30 min and last for 3-4 hours - ecstasy increases synaptic serotonin levels and then leads to prolonged serotonin depletion due to blocking of reuptake mechanisms - side effects include: hyperactivity, tremors, confusion, depression, anxiety, paranoia, sleep disruption, nausea, chills, sweating - primates given doses for 4 days showed serotonin related deficits 7 years later - memory loss is a common disorder among ecstasy users - ecstasy users had smaller parietal and striate cortices - teenage users had impaired attention and altered functioning of the hippocampus - EG: these reports suggest that ecstasy has neurotoxic effects; this may be the case, but one must also consider the findings are derived from individuals who are engaged in various risky activities, including abuse of a wide range of drugs; it is not clear how much of the brain trauma should be attributed to ecstasy - image shows binding by cannabinoid receptors in the rat brain (left) - opioid receptors in rat brain (right)

functional magnetic resonance imaging (fMRI)

- blood becomes weakly magnetic when the oxygen is removed from the hemoglobin - this allows one to detect which regions of tissue are using more blood on the basis of how much blood is being delivered and deoxygenated - the amplitude of the change is described as the BOLD response (an acronym from Blood-Oxygen-Level-Dependent - this is assumed to reflect the degree of activation of the brain tissue, as might occur from processing info or commanding a motor or emotional response - the fMRI (bold) signal is based on the amount of oxygen use by the tissue - the first successful use of MRI imaging to register changes in blood flow as a function of brain activation was done by Jack Bellaview and colleagues in 1990 - they flashed light into the subject's eyes - on and off - and looked for differences in Bold levels - they found that primary visual cortex provided the largest response

is it vegetative state or locked-in syndrome?

- brain damage can produce a coma from which the patient is unlikely to recover - they can remain in what we call a "vegetative state" for many months or years - when this occurs, the doctors and family may decide to shut down the respiratory or stop providing a liquid diet and let the patient die - a controversial ex would be Terri Schiavo, who died in 2005 after court-ordered removal of the feeding tube (against wishes of parents) - we can know that with locked-in syndrome is conscious if they can provide a small deliberate movement as a way to communicate - but someone might be fully conscious but have such severe paralysis that they are unable to make contact - one needs to find brain measures that can establish that the patient is conscious

prosthetic skin cues

- but the tactile cues is also being used to provide sensory feedback to amputees - the tactile info is delivered to electrodes that are placed against the amputated stump, and the electrical stimulation can be adjusted to provide the person with the sense that their fingers have touched and grasped objects - one investigator said: "at first we were only able to produce a buzzing sensation, but once we got the frequency right, it yielded the perception of touch" - a patient said: "I really hate going home at the end of the day because I have to leave my hand behind"

Koch, C. (2018) What is Consciousness?

- conscious is not determined by the number of neurons - the spinal cord has about a billion neurons yet it can be severed and the person still has an active mental life - the cerebellum has about 69 billion (4 times the number for the rest of the brain) - but cerebellar damage affects skill motion, rendering them less fluid, but not much else changes (if glial cells are included in the count, the total number of cells is much greater) - Koch cites the perceptual phenomenon of binocular rivalry as a way to demonstrate that subjective experience is a valid brain state and not an illusion - each eye provides the brain with a different image - while some kinds of info, e..g, depth disparity, can be synthesized into a single perception, here the image info is too different - the brain deals with that by switching back and forth from one image to the other - Koch says that this is not being done in primary visual cortex (shown at the tip of the arrows at the bottom of the diagram), but in later stages of visual processing - Koch proposes that consciousness is provided by activity in the "posterior hot zone" - in the image he is lighting up the parietal lobe and is not lighting visual circuits in the temporal lobe - EG: it is not clear why he chose to illustrate activation of the dorsal route; most cognitive neuroscientists would be discussing face recognition by the FFA on the underside of the temporal lobe; whatever the case, Koch's main point is that subjective perceptual experience is provided in the posterior half of the brain, with frontal areas providing the major control functions - stimulation and lesion studies provide additional evidence that conscious experience is provided by activation of posterior cortex

conscious, subconscious, unconscious

- consciousness: reportable states or knowledge, what can be reported as perceived, felt, or remembered - unconscious state can range from comatose (or asleep) to providing a vast reservoir of motivational states and unaccessed memories - Dehaene refers to the middle state as preconscious and relates it closely to attentional mechanisms - these consist of alternative unconscious states that could become conscious experience - this would include sensory stimuli, e.g., whether to attend to the music that is playing in the background or focus on the colors that are present in a scene - it can involve recalling specific memories from the vast store of one's memories

recap of consciousness etc.

- consideration of consciousness has led to analysis of brain activity that involves widespread interaction of brain areas - accepting subjective reports by the subject as valid data allows one to look for and hopefully establish how the brain is providing for those subjective states - the role of attention in eliciting and directing alternative mental states has provided interesting insights - the idea that synchronization of brain activity, possibly by special circuits that manifest high-frequency EEG activity, is interesting and worth further study - the nature of qualia remains controversial

global workspace

- dehaene, 2014 - he describes the brain mechanisms for consciousness as the global neuronal workspace - system dedicated to selective processing of preconscious perceptions, memory recall, and value states, e.g., drives, emotions, goals - selection of which of the many inputs to focus upon is done through an attentional control system, the result being selection from among alternative actions that will prove to be beneficial - EG: some credit Bernard Baars with this concept, including the name - preconscious mental states consist of a massive amount of sensory and memory info that can be accessed and brought into consciousness through attention - examples of preconscious activity in the brain that would accomplish: driving, listening to music while studying - dehaene asserts that attention has two facets: the ability to select and ability to sustain - it selects based on salience of the stimuli and their relevance to current goals (or other potential survival benefits) - it sustains toward accomplishing the actions that might achieve those goals - roughly one operation (perception, memory, thought) at a time is brought from the preconscious condition into conscious awareness = a large mass of preconscious info is available at any given moment, most not being accessed - one might think that more than one operation is being simultaneously attended, but this is delusion (just switching quickly from one to the other)

altered mental states

- drugs - migraines - sensory deprivation - epilepsy - schizophrenia - parkinson's disease - mania/depression

opioids and hypnotics

- further experimentation by Oliver Sacks - he shoots up a very large dose of morphine and has hallucinations of a British battle scene of Henry V in the 1400s - was transfixed for over 12 hours before coming back to reality - this is classic "opium stupor" wherein there is massive slowing of time perception - tells of taking chloral hydrate (stolen from the lab) as a sleep aid, building up to 15 times the normal dosage - his supply ran out and he had a sleepless night - the next day he was getting a sandwich and coffee, when the coffee turned green and then purple - he ran outside, but all the passengers on a passing bus had smooth white heads like giant eggs - he was having withdrawal hallucinations - from delirium tremens (DTs) - which didn't clear up for another 96 hours

EEG wavelengths

- gamma waves: received attention toward the end of the century; invoked for diverse active mental states and processes - beta waves (alpha block): indicated an alert state - theta waves: role was ambiguous; some argued that they were involved in memory storage - delta waves: very slow; indicate lack of consciousness (deep sleep)

fMRI issues to keep in mind

- goal is to provide conditions that will require specific kinds of mental activity and be able to register which zone(s) of the brain were active during that activity - it is mostly a correlational method, e.g., the image of inferotemporal cortex activity is correlated with seeing a face - there are limits: person's head must be still, special non-metallic equipment is needed for delivery of any sensory stim; one must average over many repetitions of the task - response time is slow, in the range of a few seconds, whereas electrophysiological recording methods can register events with millisecond precision - virtually all tasks generate activity over widespread regions of brain, so the researcher adjusts thresholds and does other forms of statistical filtering to show the hot spots - EG: the image that is provided requires a great many cross-computations on the raw data provided by the machine; there are a lot of parameters that can be adjusted, which affects what zones are shown as active and which are shown as relatively inactive - image shows example of work that studied how perceived threat (from electric shock) affected reaction time and provided for selective activation of the amygdala - a 2009 article by Bennett and associates made a similar point about how one can manipulate the parameters to produce fMRI marking that is spurious - EG: little dubious when the investigators show limited activation that ostensibly reflects differential function of the neuron populations; the "lateral occipital complex" receives visual info from primary visual cortex and may be a locus for registering different classes of visual objects; these authors claimed to find small differences in the location of activity in LOC that is produced by familiar objects vs novel objects; the authors appear to be banking on very subtle differences in activation

epilepsy

- hippocrates described it as the "sacred disease" and it has often been ascribed as having divine source, e.g., touched by god - it has also been feared and stigmatized over the ages - grand mal: violent convulsions, sometimes foaming at the mouth - petit mal: loss of consciousness, sometimes just gap in awareness - the general concept that it was a localized dysfunction of the brain was known since the late 1800s - from this period, William Gowers provided examples of the warning signs that might be present

hallucinations

- in the 1500s the word "hallucinations" meant "wandering mind" - in 1830 Jean Etienne Esquirol gave it the current meaning of apparitions - they are more vivid than visualizations from memory - they are externalized, i.e., perceived as coming from outside the observer, and are not voluntary - hallucinations can be bazaare - many artistic and religious images may have originated from hallucinations, and drugs have often been sued to produce hallucinations as part of religious ceremonies

is it a coma or locked-in syndrome?

- in the Count of Monte Cristo (1844), Dumas describes one of his characters as a "corpse with living eyes" for he is completely paralyzed except for being able to blink his eyes as a means of communication - his helper points to words in the dictionary and the man blinks when the right one is selected - this is the first description of "locked-in syndrome" noted in literature before it was recognized by the medial world - in 1995, Jean-Dominique Bauby, who edited the French fashion magazine Elle, suffered a stroke that produced locked-in syndrome - he was paralyzed, except for one eye and part of his head - he survived for 15 months, enough time to dictate an entire book - the physicist Steven Hawking had a progressive motor-neuron disease related to amyotrophic lateral sclerosis that eventually produced a similar condition

reticular activating system

- in the early 50s, Moruzzi & Magoun discovered that a cut that severed the forebrain from the brainstem would result in constant sleep (as indicated by EEG) - this led to speculation that structures in the brainstem provide upstream activation of the forebrain, generating wakefulness and one might say consciousness - once specific nuclei were discovered that regulate SWS and dreaming, the general concept of a reticular activating system was mostly forgotten - one reason the reticular activating system concept fell out of favor was the inability to provide much detail about the anatomy of upstream influence from the brainstem - the connections were very diffuse, which made it difficult to pin down the mechanism

evidence of functional role of brain regions

- motor: Kenneth Kwong provided evidence of selective activation of motor cortex when the person made voluntary hand movements - Nancy Kanwisher was able to get activation in the fusiform face area, and Poldrack provides a figure showing activation of this area when he looked at faces - some reports will show the location of brain activation viewed from the outer surface (image shows sulci have been expanded so that activity within the folds can also be seen)

brain modules

- much of the effort to evaluate brain function has focused on specifying the function of each region of the brain - V1: blindness - A1: impaired sound processing - S1: numbness of specific regions - V4: achromatopsia (loss of color vision) - V5: motion agnosia - broca's and wernicke's: language - hippocampus: memory (at least spatial) - many of the insights have come from damage to specific brain regions (in animals as well as humans), and from electrical recording of localized neural activity - we also discussed how the focus of brain imaging has been to demonstrate local activation of brain areas as a correlation of a specific perception, motor action, skill, motivational state, or any other mental state of special interest to the investigator

use of experimental tools that show stimulus influence with or without awareness provides a way to delineate the conscious state

- one must accept an observer's report of the subjective state as valid data - EG: note that this is a major departure from behaviorist (S-R) philosophy of proper experimental method - thus the observer's report that she is seeing two faces at one moment and a vase at the next moment is valid data, and the goal then is to see if one can detect any "signature" in brain activity for each of the perceptual states - rubin's vase - necker cube - he notes consciousness of self as a special condition that has been the subject of interest in developmental and animal psychology - the mirror test is sometimes used as a way to determine whether the subject has a clear concept of self - a classic test of self awareness places a sticker or rouge on the forehead, then shows the reflection in a mirror

Luigi Galvani

- proposed the existence of "biological electricity" and demonstrated that nerves conduct electricity to produce muscle activation

neuroimaging analysis may overstate successful replication

- recap of article by Yong Wook Hong, 2019 - how solid are fMRI results? - even when experiments have been successfully replicated, there may be reasons to question the inferences that are drawn - he argues that reports of brain activation commonly are referring to fairly large regions of the brain, e.g., orbitofrontal cortex, cingulate cortex, inferotemporal cortex, amygdala - but the size of voxels that register the activation are commonly much smaller than the areas being named - there will be hundreds of voxels in a structure as small as the amygdala, and the location of activation seen by one lab may be much different than what is seen by a subsequent lab - by averaging the activity across the full breadth of the named structure, "replication" or "confirmation of effect" may be claimed even if there were significant differences in the exact location of the activation - his team did a statistical test of this possibility, dividing data from 59 subjects into two groups and looking for consistency of pain vs social rejection on activation of cingulate cortex - they found significant differences in the location of peak activity that would have been ignored if one averaged across the cingulate cortex - they recommend more attention to detail, i.e., better statistical modeling and analysis

visual prosthesis

- retinitis pigmentosa is an inherited condition wherein the photoreceptors die; doesn't damage the ganglion cells, which are the source of the optic nerve - many methods are being tried to help restore a modicum of vision to these individuals - one captures images with a camera and transmits a reconverted version of the image to an array of electrodes that are implanted against the retina or in some cases, against primary visual cortex - the image is usually converted to a pattern of dots that activates a corresponding pattern of electrodes - most of the effort is to allow reading of large text, or to assist in being able to walk about without bumping into objects

coma study: Jain & Ramakrishnan (2020)

- review the various kinds of stimulation that have been tried for distinguishing among various comatose states, e.g., vegetative state, minimally conscious state, locked in syndrome - auditory stimuli have been used most extensively - the most effective stimuli are emotionally charged stimuli - subjects own name, narratives in a familiar voice, pictures of their own face or of family members - electrophysiological methods are easier to implement than are brain imaging methods - the P300 and P400 peak amplitude of an ERP is most predictive of recovery (image)

ERP study

- scheller et al., 2019 - goal was to compare adults and children on ability to effectively register several simultaneous cues and determine when they were congruent or incongruent - their ERP results showed an amplified brain response in children when they had to process all three cues at once - further, they provide a highly localized heat map of which brain area was providing the differential at two specific moments during the processing of the info - EG: details are not of concern here, just illustrating how investigators would use the ERP measures to assess brain activity in connection with a cognitive task that is of interest

personality and mood: Luke

- schoolteacher - developed an increasing interest in child pornography - began retaining the services of prostitutes at massage parlors - he was turned in when he made advances toward his stepdaughter and was sentenced to a 12 step program for sex addiction - the program expelled him after he repeatedly solicited sex from the nursing staff - a scan of his brain found a tumor about the size of an egg in the orbitofrontal cortex - it was removed and his pedophilia and sexual obsessions disappeared - a few years later the urges returned, and a scan showed that the tumor was again present - they again disappeared when the tumor was removed - EG: reminiscent of Phineas Gage

neuronal prosthesis

- the Brain Machine Interface (BMI) was developed by Prof Richard Anderson and his team at Cal Tech - it makes it possible for this quadriplegic patient Erik Sorto to drink a beer by controlling a robotic arm with his mind - the BMI device, shown in the artist's rendering, is an array of electrodes that is inserted into the cortex, such that the individual electrode needles can record neuronal activity as well as provide stimulation Brain Machine Interface: - the diagram shows the brain as seen from behind, with one of the BMI arrays being implanted in parietal association cortex (cyan) - electrodes from this array register Sorto's mental commands, which are interpreted by computer algorithms and converted into activation of the robotic arm and hand - sorto's goal is to command the mechanism to reach for the cup, grasp it, and lift it to his lips so that he can drink the beer - one might think that one should stimulate the motor system that lies in the frontal lobe, but Andersen says that those neurons command specific motor responses - what works is to plug into the system that commands general goals to be achieved - the system has been made more effective by adding tactile sensors to the fingers of the hand and using this to stimulate the somatosensory cortex (purple) -- this allows Sorto to perceive the finger pressure on the horizon: - after making several hundred million dollars by selling Braintree, Johnson has founded a Culver City start up called Kernel - he claims that he can shrink the EEG processing algorithms into small modules that can be mounted in a helmet - this may allow the analysis of EEG patterns that normally requires very expensive equipment into an inexpensive tool for research, clinical treatments, mind machine interface, and other useful purposes - Steve Aoki tried one of the Kernel's helmets

quantum mysticism

- the Greeks thought that we were ruled by the vicissitudes of the Gods, and by the forces exerted by the humors of the body - in the age of Descartes and Newton (17th century) there was fascination with mechanical systems - wind up toys that could spin and dance; animated fountain statuary whose actions were powered by hydraulic pressure - Newton was able to specify simple equations relating mass, velocity, and distance that predicted the strength of gravitational attraction between the sun and the planets - his equations specified the arc traveled by a cannonball, and countless other physical states of nature - many in the scientific community (and some philosophers) developed a strong belief in determinism - the idea of a "clockwork universe" argued that all events within the universe were based on the laws of physics (which would include chemistry) - however, some philosophers and scientists objected to rigid physical determinism - real physical systems are extremely complex, and one cannot know, and certainly cannot control, all the conditions that might lead to a given outcome - poincare voiced this view, but the concept did not carry much weight until Edward Lorenz popularized the concept of the "butterfly effect" - Lorenz modeled weather and was troubled when he found that extremely small changes in the model parameters could greatly alter the weather pattern that the models predicted - making a tiny change in the value of a model parameter could dramatically change the prediction from warm and dry to wet and stormy - he coined the term "butterfly effect", a butterfly flaps its wings in the Amazon and two years later a thunderstorm appears in Texas - chaos theory - Lorenz was providing an example of what is now known as chaos theory

agency

- the belief that one's thoughts and actions are one's own can be described as a sense of "agency" (specifies that you are the root cause of the action) - Wegner asked subjects to dress in a black smock and wear white gloves - the subjects' arms were hanging down by her side - a research assistant stood directly behind her, also dressed in black and wearing white gloves, with the assistant's arms assed around the subject - as the subject looked in the mirror, she saw the hands clap, but did not perceive them as her own - but if she was first told to clap her hands, and then saw them clap, she sensed that she herself had initiated the action - Libet et al (2013) - if one decides to make a movement, is one's awareness of having made the decision a manifestation of free will? - for a voluntary action such as kicking out with a leg or turning one's head, there is a slowly rising EEG potential that can be recorded from the crown of the head - it is called the "readiness potential" - it precedes the actual motion by up to a second - Libet asked his subjects to spontaneously flex their wrist whenever they felt like it - he provided a timing clock to help them specify when this movement was executed - they were very accurate in doing so - he then asked them to say when they decide to make the movement, which they did as well - but the readiness potential recorded by the EEG preceded the decision to move by up to half a second - brain activity that led to the decision was being generated prior to any awareness of having made the decision - follow up using fMRI has found brain activation that precedes the decision by as much as 8 seconds - EG: this makes the case that one's conscious awareness is not a starting point for a decision but comes somewhere downstream, i.e., at a later moment

but can computers think and plan?

- the consensus, in the late 20th century, was that they'd never be capable of mastering the complexity of thought needed for winning at chess - in 1997, IBM's Deep Blue beat chess champion Garry Kasparov - in 2016, AlphaGo beat Go champion Lee Sedol - the computer has the benefit of massive memory and high speed, making it possible to store thousands of play variations and select the moves that are most likely to yield a win - they depend very little of the kind of strategic analysis and theory that a human would use - virtual gaming, like that provided by the video game StarCraft II, represents a greater challenge to those programming artificial intelligence algorithms - nonetheless, on Dec 12, 2018, a program known as Alpha Star, written by the London-based company Deep Mind, beat StarCraft II champion Dario Wunsch, winning the series of matches 5 to 0 - the bottom line is that the computer can outperform humans on all tasks that have structured performance rules - noise - turns out that a major challenge is in being able to discriminate objects when the stimulus is severely degraded - there are many problems with discrimination of auditory info, but we will focus on vision (image) - shadows may make it difficult for a machine-vision algorithm to discriminate objects, as they break up the contours that are critical for identifying the objects - a heavily shadowed road might cause problems for an autonomous vehicle

Koch, C. & Tononi, G. (2019) Testing for Consciousness in Machines

- they say that computers have an even bigger problem - any 6 year old can see what is wrong with the photo shown, but it provides the kind of configuration that would not be seen as odd by most machine-vision algorithms - we can judge whether the elements fit together, the machine cannot - they say that conscious experience has two basic properties: each experience is highly informative, providing info that rules out countless other possibilities; the info is integrated, fused into a single configuration that has the goal of correctly representing relationships among the percepts and/or memories - they describe how to make examples from the web by dividing photos with a black strip and mixing left and right components - only those that make sense will appear as a unified photo - or insert arbitrary objects; or replace an object with another that is inappropriate - the point is that our memories are stuffed with a massive amount of info, much of it about relationships among stimuli - not just vision, but hearing, touch, smell, taste - and not just within a single sensory domain; we also have memories of what are the sounds that might go with a given object or how it would feel if touched, etc. - the amount of info is ginormous, and this amount of knowledge is required for a computer to stimulate the human mind

why try to simulate the mental functions of the brain?

- we have invented countless tools that have provided benefit over the millennia - language: allows knowledge of one person to be transmitted to another - drawing: allows what a person sees to be conveyed to another - writing: allows more permanent and transportable instruction of others - printing: expands the number of others who can receive the knowledge - cameras: captures images with fidelity to the actual scene - sound recording: captures sounds with fidelity to the source(s) - electronic info transmission: widespread dissemination of knowledge - computers: flexible info processing and storage

robots with feelings? (Man & Damasio)

- we strive to create intelligent machines, meaning that they can achieve goals - but what goals need to be achieved? - a critical goal for biological organisms is self preservation and doing so requires that body states must be maintained within limits - Man & Damasio argue that current robots lack "selfhood" -- they have no sense of what is beneficial to themselves and on what basis to assess risks and rewards - providing a requirement to maintain their survival into the future will more closely approximate biological imperatives, as well as emotional states that contribute to that survival - EG: a key element of the plot line in the movie "Ex Machina" was the android's concern about what would happen to her once the genius that created her moved on to produce the next model - what could go wrong with this idea? - in the science fiction movie "2001: A Space Odyssey", the ship's computer, named HAL, killed all but one of the crew due to a logical inference about contradictory program directives - EG: this was just one of countless depictions of how machines can bring harm to humans - the smarter the machine, the greater the harm that can be rendered - linking the machines into an extended network increases the complexity of the system, making it ever harder to stop the actions being perpetrated - Isaac Asimov wrote about this challenge very early in the development of computers - his three rules seem appropriate, but there are countless details that would be a challenge to the best human judgment - one might hope that decisions being made by artificial intelligent beings would be less prone to flaws - Man & Damasio argue for roughly the reverse of what Asimov proscribed - their directives to the intelligent machine are: feel good (the first directive is for the machine to take care of itself - to pursue homeostatic well being); feel empathy (the second is to feel the pleasure and pain of others as its own) - EG: their argument does indeed highlight the question of whether one can ever provide clear and comprehensive directives about what constitutes harm to humans (Asimov's first law); perhaps it is better to have a sense of how the action would impact oneself, which appears to be what Man & Damasio recommend


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