Susan Greenfield - Journey to Centers of Mind
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Greenfield; Centers of Mind 1 Inner world of your particular consciousness arises from a kaleidoscope of memories,  prejudices, hopes, habits, and emotions, which are constantly expanding and enriching your life as you develop.
Greenfield; Centers of Mind 2 Brain electricity and brain chemistry are ultimately all there is to your mind. 1
Greenfield; Centers of Mind 2 We experience consciousness most the time we are not asleep. 0
Greenfield; Centers of Mind 3 At this time there are simply no terms of reference, no framework for capturing an objective description of subjective consciousness. 1
Greenfield; Centers of Mind 4 We all "know" what consciousness is, but find it impossible to articulate what it is using an objective frame of reference. 1
Greenfield; Centers of Mind 5 Fighting and fleeing are extreme examples of arousal. 1
Greenfield; Centers of Mind 9 Mental life of one individual's mind is not transferable to any other brain. 4
Greenfield; Centers of Mind 9 A signature is the only universally accepted outward sign of an individual. 0
Greenfield; Centers of Mind 10 We produce, day after day, a consistent signature. 1
Greenfield; Centers of Mind 10 Everything we see, hear, taste, touch, and smell is laced with associations from previous experiences. 0
Greenfield; Centers of Mind 10 World of a newborn infant, a world of meaningless abstract forms and sounds. 0
Greenfield; Centers of Mind 10 Associations can reasonably be assumed to contribute to a consistent profile of individuality. 0
Greenfield; Centers of Mind 12 How exactly does nervous tissue calls consciousness? 2
Greenfield; Centers of Mind 20 Neuronal communication. (diagram) 8
Greenfield; Centers of Mind 36 Computer HAL died in the film 2001. 16
Greenfield; Centers of Mind 37 Daniel Dennett (1991) -- proponents of mechanical minds, similarities between the brain and modern parallel processing devices. 1
Greenfield; Centers of Mind 39 At least 50 basic neuronal shapes in the brain,    which can affect the efficiency of signaling. 2
Greenfield; Centers of Mind 39 Neurons with very long dendrites. 0
Greenfield; Centers of Mind 39 Small cells are excited more easily than larger ones.  (Smaller cells have higher resistance, so any current produced as an incoming signal is transformed into a larger voltage) 0
Greenfield; Centers of Mind 39 Size, together with the number and length of processes that extend from a cell are critical factors in its behavior. 0
Greenfield; Centers of Mind 39 Physical shape of neurons in the brain goes a long way in determining neuronal response. 0
Greenfield; Centers of Mind 40 Interactions between neurons and neuronal aggregations are most accurately described as networks (a combination of hierarchies and parallel processors). 1
Greenfield; Centers of Mind 40 Neuronal networks are the functional building blocks of the brain. 0
Greenfield; Centers of Mind 40 Neurons in a network entail a certain amount of redundancy, if we assume several neurons can do the same job. 0
Greenfield; Centers of Mind 40 Neuronal network redundancy acts as insurance against the death of an otherwise unique single cell. 0
Greenfield; Centers of Mind 40 Learning is the key property of neurons in groups. 0
Greenfield; Centers of Mind 40 Shifting relations among neurons in a network. 0
Greenfield; Centers of Mind 41 Psychologist Donald Hebb -- the more two neurons communicate with each other, the easier communication becomes (1949). 1
Greenfield; Centers of Mind 41 Weighting the strength of communications among various neurons in a network depends upon prior experience or learning. 0
Greenfield; Centers of Mind 41 The more certain synaptic contacts in the neural network are used, the more efficient those synapses become. 0
Greenfield; Centers of Mind 43 Researchers in 1973 observed and named long-term potentiation (LTP).  When stimulated intensively, neurons become more sensitive to subsequent stimulation for several hours later. 2
Greenfield; Centers of Mind 44 Hebb's ideas of strengthening. 1
Greenfield; Centers of Mind 44 When a particular chemical fits into a receptor, it acts as a trigger to open or close channels in the cell membrane for the subsequent passage of a particular ion in and out of the cell. 0
Greenfield; Centers of Mind 45 Calcium is a far more versatile and powerful ion inside a neuron than sodium. 1
Greenfield; Centers of Mind 45 Calcium ions can promote many changes, such as the activation of genes. 0
Greenfield; Centers of Mind 45 When certain genes are activated,    the neuron may change the amounts and types of particular chemicals it contains    and even undergo a modification    in its overall appearance.    It will have been adapted over a period of time    to the sustained increase in input.    It's response will have become weighted    to respond in different ways    to future signals. 0
Greenfield; Centers of Mind 45 After you gain experience for a while,    during a period of rest,    your brain sets in motion LTP,    which is responsible for your adapting to or    learning from    the experience you have just had. 0
Greenfield; Centers of Mind 46 Mechanism of long-term potentiation (LTP); schematic drawing of a slice of hippocampus. (diagram) 1
Greenfield; Centers of Mind 46 Nerve fibers from the entorhinal cortex, enter the hippocampus and make contact with cells in the dentate gyrus. 0
Greenfield; Centers of Mind 46 Cells in the dentate gyrus make contact with cells in CA3. 0
Greenfield; Centers of Mind 46 Cells in CA3 make contact with output pyramidal cells in CA1. 0
Greenfield; Centers of Mind 47 Humans do not have to be on the move to gain experience; intense thought or stimulating conversation or attendance at a lecture generates neural activity. 1
Greenfield; Centers of Mind 47 Over time,  LTP decays. 0
Greenfield; Centers of Mind 47 LTP can occur rather promiscuously in a variety of totally different situations. 0
Greenfield; Centers of Mind 47 Rudolfo Llinás has shown that if inputs to a cell cause an on-and-off excitement in rapid oscillation, then a potentiation can also occur. This type of LTP is not mediating memory, but may represent a requisite condition related to it, such as attention. 0
Greenfield; Centers of Mind 48 Loose relationship    between the physical mechanism of LTP    and the phenomenological process    of memory. 1
Greenfield; Centers of Mind 50 Apart from size and the percentage of brain it represents,    cerebellum    has changed little    during animal evolution. 2
Greenfield; Centers of Mind 51 When we ski,    drive an automobile,    or play the piano,    we perform the manual movements of these skills    automatically. 1
Greenfield; Centers of Mind 51 Although we are conscious, we are not consciously planning each movement by which we execute a skill. 0
Greenfield; Centers of Mind 52 Modulocircuitry of the cerebellum.  (diagram) 1
Greenfield; Centers of Mind 52 Neurons of the cerebellum are organized into repeating modules. 0
Greenfield; Centers of Mind 52 Purkinje cell, the major cell of the cerebellum, receives two types of inputs directly, (1) climbing fibers and (2) parallel fibers; as well as a third, indirect input (mossy fibers).  Purkinje cell sends its output signal to neurons deep within the cerebellum, the cerebellum nuclei. 0
Greenfield; Centers of Mind 53 We rarely respond in exactly the same way a second time to a given situation. 1
Greenfield; Centers of Mind 53 There is always some uncertainty in neuronal events. 0
Greenfield; Centers of Mind 53 Neurophysiologists speak of the probability of neuronal events rather than of certainty. 0
Greenfield; Centers of Mind 53 Roger Penrose in 1989 pointed out that it is hard to form fixed and rigid rules for intuition and common sense. 0
Greenfield; Centers of Mind 54 Memories are labile and highly suspect to revision. 1
Greenfield; Centers of Mind 54 How often we rewrite past events, suppressing certain scenes and distorting others, to make ourselves seem braver, clever,  wittier, or more justified in acting a certain way.    Capricious and inconstant type of memory. 0
Greenfield; Centers of Mind 54 Spontaneous mental states such as nostalgic daydream or fantasy, which entail neither sensory inputs nor movement outputs. 0
Greenfield; Centers of Mind 54 Form abstract concepts    such as love, truth, and beauty    from the bits and pieces of information    flooding into us. 0
Greenfield; Centers of Mind 54 Our actions    are frequently generated from    an internal thought,    not external sensory triggers. 0
Greenfield; Centers of Mind 54 Our minds    are frequently driven by    some external sensory inputs. 0
Greenfield; Centers of Mind 54 Some movements are stereotyped or almost stereotyped --    knee-jerk;    jumping out of the way of a car;    or even routine driving a car much of the time. 0
Greenfield; Centers of Mind 55 Frequently we are proactive, carrying out various acts that are seemingly spontaneous but far from random, and are thus engaged in voluntary movement. 1
Greenfield; Centers of Mind 55 Behavior not requiring consciousness,    such as stereotyped automatic motor skills. 0
Greenfield; Centers of Mind 55 LTP is not the essence of memory, but a possible requirement for it. 0
Greenfield; Centers of Mind 55 Computational cognitive processing may be a necessary but not a sufficient requirement for processes in the brain leading to consciousness. 0
Greenfield; Centers of Mind 55 One of the most vigorous opponents of the view that an algorithmic, computational basis of consciousness consciousness can ever be found is Roger Penrose.  He cites mathematician Kurt Gödel's theorem, which states that the validity of an argument in logic is dependent on premises that are additional to that argument.   [arcane and etherial] 0
Greenfield; Centers of Mind 55 Penrose states that our consciousness is governed by something more than a fixed set of rules, more than a series of algorithms. 0
Greenfield; Centers of Mind 55 Consciousness would be nothing without intuition, common sense, and insight. 0
Greenfield; Centers of Mind 56 Advocates of a mechanical mind, such as Churchland, claim that motives, moods, and appetites may be part and parcel of information processing to a degree  hitherto unsuspected. 1
Greenfield; Centers of Mind 59 Blindsight patients possess some kind of visual ability, but this ability has become totally disassociated from conscious awareness of events in the visual field.  Weiskrantz (1974) 3
Greenfield; Centers of Mind 59 Critical factor for consciousness of movement    is that two particular parts of the cortex (V1 and V5)    should be able to interact.    Neurons in each of these two regions must be able to sustain a dialogue,    emit signals in synchrony,    oscillating at the same frequency.     It is this oscillation,    this neuronal cooperativity,    that is crucial for conscious perception of movement. 0
Greenfield; Centers of Mind 60 The idea of consciousness    arising from brain regions working together,    achieve more than their mere sum,    is an emergent property. 1
Greenfield; Centers of Mind 60 Multiple brain regions    work transiently together.    By their reverberating interaction,    their temporary and transient dialogue,    consciousness is emergent. 0
Greenfield; Centers of Mind 60 A dynamic, resonating dialogue among parts of the cortex may well be necessary in order to explain the paradox the blindsight. 0
Greenfield; Centers of Mind 61 We are either conscious or unconscious of things    according to their importance, strength, or intensity. 1
Greenfield; Centers of Mind 61 Strength of objects of our consciousness might determine the extent of the dialogue among participating brain regions. 0
Greenfield; Centers of Mind 63 Prosopagnosia literally means a failure to recognize faces. 2
Greenfield; Centers of Mind 65 Split brain -- in certain cases of severe epilepsy,    surgically severing the corpus callosum    prevents the spread of the seizure    from one hemisphere of the brain to the other. 2
Greenfield; Centers of Mind 67 Experiments with human split brain patients    confirmed that the two halves    can work independently of each other 2
Greenfield; Centers of Mind 67 Consciousness arises    as a result of traffic to and from    many brain regions,    some of them within the central part of the brain,    well below the cortex    and far below the area that is cut apart in split brain patients. 0
Greenfield; Centers of Mind 67 Consciousness may be variable,    but it does not depend on    the degree of incoming information    from any one sensory modality. 0
Greenfield; Centers of Mind 67 If a person is in a quiet, dark room,    consciousness is not diminished,    although it is obviously quite different from    a normal lighted room. 0
Greenfield; Centers of Mind 67 Split brain cases    show that the two halves of the brain    process incoming information separately. 0
Greenfield; Centers of Mind 68 Memory appears to be in inextricably linked to consciousness. 1
Greenfield; Centers of Mind 75 Ongoing stimulation of the five senses    is not necessary for consciousness. 7
Greenfield; Centers of Mind 77 Unconsciousness is graded and meshes gradually with consciousness. 2
Greenfield; Centers of Mind 78 Consciousness is continuously variable    and can occur to greater or lesser extents at different times. 1
Greenfield; Centers of Mind 82 Rigid distinctions    among higher order consciousness,    primary consciousness,    and no consciousness    are not very helpful. 4
Greenfield; Centers of Mind 82 Consciousness deepens gradually as an animal's brain grows and develops. 0
Greenfield; Centers of Mind 82 Variations and degrees of consciousness    continue throughout the rest of our lives. 0
Greenfield; Centers of Mind 82 There are times    when we are tired    or have the flu    or overindulged in wine,    when our consciousness will be blunted. 0
Greenfield; Centers of Mind 82 There are times, such as when we have just fallen in love    or are on an isolated beach or listening to Mozart, when we have never felt more alive, when our consciousness seems heightened. 0
Greenfield; Centers of Mind 84 Associations occur    as our neurons form connections in certain ways    as the result of exposure to particular environments,    utilizing mechanisms such as Hebbian weighting. 2
Greenfield; Centers of Mind 84 Connections among neurons    are highly plastic    and capable of great change. 0
Greenfield; Centers of Mind 84 Even in the mature brain,    the continuing ability to learn and remember    is mediated by neuronal connection plasticity,    which retains the ability to adapt to inputs    as we go through life. 0
Greenfield; Centers of Mind 84 Consciousness emerges    in relation to the complexity    of neuronal interactions. 0
Greenfield; Centers of Mind 85 Consciousness    is a property of many transient groupings of neurons.     Our brains are a restless grouping and re-grouping    of temporarily relevant neurons    with greater and lesser connectivity. 1
Greenfield; Centers of Mind 88 A property of consciousness    is its spatial multiplicity    combined with temporal unity. 3
Greenfield; Centers of Mind 88 Aggregations of neurons must not be committed full-time and irrevocably to consciousness; they should have no special feature. 0
Greenfield; Centers of Mind 88 Consciousness    may be generated at different times    by shifting populations    composed of different groups of neurons. 0
Greenfield; Centers of Mind 89 Non-specialized groups of cells are distributed throughout the brain, and these groups are constantly reforming their connections and changing their size and pattern.  Such groups of cells are the appropriate physical bases for multiple potential consciousnesses, only one of which is realized at any one time. 1
Greenfield; Centers of Mind 89 Schizophrenic trains of consciousness    can change too rapidly upon one another    so that one line of thought cannot be sustained    but is sidetracked    by extraneous and irrelevant association. 0
Greenfield; Centers of Mind 89 Schizophrenic patient    was unable to disregard    whatever invaded  his senses. 0
Greenfield; Centers of Mind 90 Effects of hallucinogenic drugs have often been compared with the symptoms of schizophrenia. 1
Greenfield; Centers of Mind 90 Central problem with hallucinogenic drugs    is that the person is overly obsessed with an object or thought    or is too readily distracted    on some tangential or idiosyncratic pathway. 0
Greenfield; Centers of Mind 90 Consciousness-changing effects of hallucinogenic drugs or schizophrenia. 0
Greenfield; Centers of Mind 91 We are always aware of something at any one time.    It is a contradiction to be conscious of nothing. 1
Greenfield; Centers of Mind 91 Consciousness can be focused on an internalized representation, such as a hope or a memory. 0
Greenfield; Centers of Mind 91 Usually, we are receptive to both our inner thoughts    and the outside world. 0
Greenfield; Centers of Mind 91 Consciousness always entails a stimulus or focus; it develops from a kind of epicenter. 0
Greenfield; Centers of Mind 91 Consciousness devolves from some sort of triggering epicenter. 0
Greenfield; Centers of Mind 92 Two types of pain are objectively recognized --    (1) fast pain, transmitted in the brain quickly by way of myelinated nerves,    is relatively easy to localize,    (2) slow pain, a far more unpleasant experience,    is transmitted slowly on unmyelinated nerves. 1
Greenfield; Centers of Mind 92 Only slow pain is effectively combated with morphine. 0
Greenfield; Centers of Mind 92 In one of the great discoveries of modern neuroscience,    sensation and suppression of pain    are linked to a naturally occurring morphine in the nervous system,    enkephalin (1986). 0
Greenfield; Centers of Mind 94 Degree of pain perception    can be as affected by attitudes and beliefs,    as well as emotional and psychological states. 2
Greenfield; Centers of Mind 94 Patients taking morphine    have claimed that they can still sense the pain,    but it is no longer relevant or significant --    i.e.,  it does not dominate their consciousness. 0
Greenfield; Centers of Mind 94 When consciousness starts to shrink in the first stages of anesthesia, there is also analgesia, reduced awareness of pain. 0
Greenfield; Centers of Mind 94 Consciousness    of the same noxious stimulus    can certainly vary    according to circumstances. 0
Greenfield; Centers of Mind 94 A variable, or waxing and waning consciousness, devolving around a particular epicenter. 0
Greenfield; Centers of Mind 95 Degree of consciousness can be the product of the extent of associations triggered by an epicenter. 1
Greenfield; Centers of Mind 95 Power of an epicenter    can be defined in terms of the number of neuronal associations    recruited. 0
Greenfield; Centers of Mind 95 Cognitive associations,    such as anticipating a pain,    will make the pain worse    and our consciousness of the pain    more extensive. 0
Greenfield; Centers of Mind 96 "Priming" has proven so valuable, and psychoanalysis has furnished its amazing revelations. 1
Greenfield; Centers of Mind 96 Identification of associations normally covert and constituting the quality of a moment of consciousness. 0
Greenfield; Centers of Mind 96 Consciousness can be viewed qualitatively in terms of different neuronal assemblies, and quantitatively in terms of the size of the neuronal assembly and the extent of its interconnections. 0
Greenfield; Centers of Mind 96 The neuronal assembly is recruited by a triggering epicenter. 0
Greenfield; Centers of Mind 96 At any one time, one neuronal assembly will predominate, only to give way to a new grouping of a greater or smaller size, which in turn will be superseded by a third, and so on. 0
Greenfield; Centers of Mind 96 If consciousness is a continuum such that it can vary quickly in time, then the degree of consciousness would be directly proportional to the extent of the objects or concepts entailed and the number of diverse and idiosyncratic associations triggered. 0
Greenfield; Centers of Mind 97 Concentric description of consciousness is based on a triggering epicenter which sets in motion nonlinear, concentric associations. The more extensive or sustained the associations are, the more consciousness will be experienced at that particular time.  We are not conscious of each of these associations as separate components.  The components conspire together to give a single experience at a specific moment in time. 1
Greenfield; Centers of Mind 97 Consciousness is spatially multiple yet effectively single at any one time.  It is an emergent property of noncommitted and emergent groups of neurons that is continuously variable with respect to and always entailing a stimulus epicenter. 0
Greenfield; Centers of Mind 97 If consciousness is an emergent property, it means that the whole is more than the sum of its parts. 0
Greenfield; Centers of Mind 97 Importance of the relationship among components in giving rise to a higher order of product was introduced in 1912 by a group of German psychologists who call their philosophy gestalt (pattern). 0
Greenfield; Centers of Mind 98 Idea behind the gestalt school of thought is that perception is global, not local; objects or features are perceived in relation to one another, giving a final holistic view that cannot be inferred from the individual components alone. 1
Greenfield; Centers of Mind 99 Behaviorist school of thought popularized later by B. F. Skinner. 1
Greenfield; Centers of Mind 99 Neuronal gestalt -- a highly variable aggregation of neurons which is temporarily recruited around a triggering epicenter. 0
Greenfield; Centers of Mind 99 Size of the gestalt corresponds directly and simultaneously to the degree of consciousness at a given time. 0
Greenfield; Centers of Mind 100 Formation of neuronal gestalts and subsequent generation of consciousness are influenced by factors in the external environment. 1
Greenfield; Centers of Mind 100 Size of an existing gestalt, the depth of our current consciousness, influences how we interpret sensory inputs as they bombard us from the outside world. 0
Greenfield; Centers of Mind 100 Arousal is a powerful factor in determining the final quality of consciousness, although it is not the same as consciousness. 0
Greenfield; Centers of Mind 100 Arousal can be described as a generalized degree of alertness: it is low when we a relaxed and high when we are frightened or angry. 0
Greenfield; Centers of Mind 100 Electroencephalogram, EEG, uses electrodes on the scalp to record the combined output of neurons in the cortex. 0
Greenfield; Centers of Mind 100 When neurons create low-frequency, high-amplitude waves, where neurons work together in slow and steady unison, arousal is low. 0
Greenfield; Centers of Mind 100 In non-REM sleep, the EEG gives a characteristic waveform that is very different from when we dream. 0
Greenfield; Centers of Mind 101 During dreaming, the EEG pattern becomes desynchronized; neurons are more active, and the pattern recorded is far more scrambled, resembling that when we are awake and alert. 1
Greenfield; Centers of Mind 101 When arousal is high, we find it hard to sit still and concentrate on any one issue. 0
Greenfield; Centers of Mind 101 Attention has been referred to as focused arousal. 0
Greenfield; Centers of Mind 101 Normal behavior can be viewed as a compromise between arousal and attention.  As we move around the world, we become excited and aroused by new and different features, but at the same time we focus attention to make sense of the new features. 0
Greenfield; Centers of Mind 101 We are constantly balancing a tendency for distraction with a need to pay attention. 0
Greenfield; Centers of Mind 101 In the dream world, rapid shifts of scene and highly idiosyncratic associations defy logic and common sense. 0
Greenfield; Centers of Mind 101 In the dream world, multiple potential consciousnesses, all jockeying for dominance. 0
Greenfield; Centers of Mind 101 Since there is no guiding restraining or overriding sensory input in the dream world, no neuronal population is sufficiently extensive in its recruiting associations to last very long or to ensure a smooth continuity of awareness. 0
Greenfield; Centers of Mind 102 Dream states can be generated by relatively modest neuronal aggregations, where ripples from the epicenter are weak in the absence of ongoing external sensory priming.  The depth of consciousness at any one time is slight, and the gestalts are small. 1
Greenfield; Centers of Mind 102 When we are very excited or highly aroused, it is hard to stay still and concentrate on any one idea. Consciousness is a disconnected jumble of impressions, reactions, and surprises at each new sight.  Consciousness in such circumstances can be interpreted as one of small gestalts. 0
Greenfield; Centers of Mind 102 When we are dreaming we can scarcely be said to be highly aroused; we are insensitive to our immediate sensory world.  It is possible, then, that very low of arousal levels (dreaming), like very high ones (excited), have the same result, small gestalt formation. 0
Greenfield; Centers of Mind 102 Critical difference between the dreaming state and the excited wake time state is a recruiting power or strength of the epicenter. 0
Greenfield; Centers of Mind 102 When awake and highly aroused, the sensory epicenter is very powerful: External objects are strong stimulants with the potential for recruiting large numbers of neurons. Due to constant distractions from new epicenters available as well as ongoing movement affording the opportunity of still more novel sensory experiences, epicenters recur in rapid succession.  Each gestalt does not have time to grow, but is jostled out of place while it is still small. 0
Greenfield; Centers of Mind 102 When we sleep, the memories that constitute the fragile epicenters of the scraps of consciousness of our dreams are relatively weak  The gestalts in this case do have time to grow, but the epicenter is not sufficiently strong to maintain such growth. Hence, rival highly transient, and only tenuously associated gestalts slides into place, and you are suddenly transposed from a house in England to an African beach. 0
Greenfield; Centers of Mind 103 The fragile epicenter of neuronal gestalt in our dreaming consciousness is still more powerful than no consciousness, no gestalt at all. 1
Greenfield; Centers of Mind 103 It is harder to wake someone in REM sleep who is relatively more aroused than someone in non-REM sleep. 0
Greenfield; Centers of Mind 103 In non-REM sleep there is no competition for  the formation of the first gestalt that will comprise our waking consciousness of an alarm bell or whatever has dragged us back into awareness.  When we are dreaming, a gestalt has been formed, however fragile. This scrap of consciousness serves as a modest initial form of competition to the external, powerful alarm bell.  It is a subtle interaction between arousal and gestalt size that dictates our prevailing consciousness. 0
Greenfield; Centers of Mind 104 Arousal is a continuously variable factor.  Psychologists have for a long time plotted levels of arousal against performance in certain tasks.  Efficiency at a task is optimal in the middle range of arousal; if we are too relaxed or too distracted, then performance declines. 1
Greenfield; Centers of Mind 104 Maximal efficiency corresponds to the situation of large gestalt formation. 0
Greenfield; Centers of Mind 104 There is a impossible balancing between attention and arousal. 0
Greenfield; Centers of Mind 104 There is a trade-off in terms of survival value between being able to concentrate and being aware of change. 0
Greenfield; Centers of Mind 104 Arousal is in interactive factor, along with the strength of epicenter, in determining the final size of gestalt formation and hence consciousness. 0
Greenfield; Centers of Mind 104 High and low degrees of arousal can be associated with the formation of small gestalts, rapidly shifting states of shallow consciousness, whereas an intermediate level of arousal favors the formation of fewer, longer-lasting, and larger gestalts, amounting to promoting a deeper consciousness, attention. 0
Greenfield; Centers of Mind 104 Consciousness is spatially multiple yet effectively single at any one time. 0
Greenfield; Centers of Mind 104 Consciousness is an emergent property of nonspecialized and divergent groups of neurons that is continuously variable with respect to, and always entailing, a stimulus epicenter. 0
Greenfield; Centers of Mind 104 Size of the gestalt, and hence the depth of prevailing consciousness, is the product of the interaction between the recruiting strength of the epicenter and the degree of arousal. 0
Greenfield; Centers of Mind 105 Idiosyncratic connections have been formed not just a result of one's genes, but, more significantly, as the brain interacts with the environment. 1
Greenfield; Centers of Mind 105 Transition from one conscious state to the next is unique for any individual, as the "ripples" emanating from the epicenter recruit a particular pattern of neurons. 0
Greenfield; Centers of Mind 105 Our continuity of consciousness occurs as a chain of associations devolved around an epicenter. 0
Greenfield; Centers of Mind 105 "Ripples" on one gestalt spread out to ever more remote associations, so a new epicenter starts to recruit neurons into a gestalt. This new gestalt supplants the original, and our consciousness subtly shifts. 0
Greenfield; Centers of Mind 106 Individual size and shape of gestalts, and the particular transition from one to the next, might actually be a plausible basis for an enduring individuality. 1
Greenfield; Centers of Mind 106 We are not aware of all of the associations that might be contributing to a specific state of awareness. 0
Greenfield; Centers of Mind 106 Consciousness theory must include: (1) the importance of the intensity of the focus or epicenter of consciousness,  (2) the importance of previous associations (memory), the presence of a consciousness in animals and children that is different from adult humans, and the elimination of a fixed consciousness center. 0
Greenfield; Centers of Mind 106 We are speaking of large groups of neurons in time as well as space, and giving them a special name (gestalts). 0
Greenfield; Centers of Mind 110 Transient teaming up of neurons into a gestalt. 4
Greenfield; Centers of Mind 110 How aggregations of neurons might operate and function in both time and space like theoritical gestalts. 0
Greenfield; Centers of Mind 111 Gestalts do not have a rigid, fixed anatomy and are not localized in one brain area. 1
Greenfield; Centers of Mind 111 Transient aggregations of neurons are forming, operating, and reforming all the time in multiple areas of the brain, such that at any one moment one particular subnetwork generates consciousness. 0
Greenfield; Centers of Mind 111 Neuronal gestalts are influenced by arousal. 0
Greenfield; Centers of Mind 111 Arousal and gestalt formation act in concert to generate consciousness. 0
Greenfield; Centers of Mind 111 Donald Hebb's "assembly of neurons" as a network of connections between neurons where communication is made easier or strengthened by experience. 0
Greenfield; Centers of Mind 111 Correlational assemblies of neurons are groups of neurons active to the same extent, in the same way, at the same time. 0
Greenfield; Centers of Mind 112 Neuronal gestalts are a type of neuronal assembly. 1
Greenfield; Centers of Mind 112 Gestalt is defined as a highly variable aggregation of neurons that is temporarily recruited around a triggering epicenter. 0
Greenfield; Centers of Mind 112 Not all neuronal assemblies are gestalts, but all gestalts are neuronal assemblies. 0
Greenfield; Centers of Mind 113 Neuromodulation occurs when certain neurochemicals do not necessarily participate in direct signaling but, rather, reduce or enhance the excitability of a neuron in response to a signal coming in at another time 1
Greenfield; Centers of Mind 113 Neuronal groups, even of the simplest, hardwired, and smallest kind, are capable of giving rise to highly versatile emergent properties, depending upon how the cells have been biased. 0
Greenfield; Centers of Mind 114 Modular arrangement of neurons in the cerebellum. 1
Greenfield; Centers of Mind 114 Modular arrangement of the cerebellum consists of two inputs converging on an output cell.  Even this elementary arrangement allows for a simple form of automatic motor learning. 0
Greenfield; Centers of Mind 114 Cortex consists of six anatomically distinguishable layers parallel to the surface of the brain. 0
Greenfield; Centers of Mind 114 Cortex neurons in each layer reach up and down, at right angles to the brain surface, to connect in vertical columns. 0
Greenfield; Centers of Mind 114 Columns are the basic modules of the functionally complex cortex. 0
Greenfield; Centers of Mind 114 In more highly evolved animals, the critical factor that changes is not the number of layers and not necessarily the number of cells, but the potential complexity of connections among the cells. 0
Greenfield; Centers of Mind 114 Neuronal gestalts are transient groupings of neurons where the connections among them are only temporarily functional. 0
Greenfield; Centers of Mind 115 Groups of neurons in the brain do not have to be irrevocably hardwired. 1
Greenfield; Centers of Mind 115 During development, dramatic occurrences in the outside environment can change the internal arrangement of brain cells. 0
Greenfield; Centers of Mind 119 When the thalamus and the cortex are acting in unison, there is evidence for focused arousal. 4
Greenfield; Centers of Mind 119 Perhaps under direction from the thalamus, a synchrony may occur among subsets of neurons in the cortex, where members of transient groups can be recruited over relatively large distances, up to 7 mm apart. 0
Greenfield; Centers of Mind 119 In a normal situation, the nearer one neuron is to another, the more likely they are to be excited by each other, since any chemical messenger release locally within a group will not have far to diffuse. 0
Greenfield; Centers of Mind 119 Recruitment of neurons into a gestalt is not on the basis of mere proximity. 0
Greenfield; Centers of Mind 120 It is far more flexible to generate an extensive gestalt of neurons spanning a large area from which they are selectively recruited, perhaps by their frequency of oscillation. 1
Greenfield; Centers of Mind 120 Wolf Singer has shown that disparate neurons large distances apart in the area of the cortex associated with vision can oscillate in their excitability in a synchronous fashion, if they are processing respective parts of a pattern with a common feature. 0
Greenfield; Centers of Mind 120 Gestalts are ceaselessly at work, shuffling and reorganizing their internal communications. 0
Greenfield; Centers of Mind 120 Oscillations of specific groups of neurons have been shown to have a momentary frequency, i.e. they do not oscillate at a fixed rate under a particular condition all the time. 0
Greenfield; Centers of Mind 120 Oscillations and neuronal groups can vary from one moment to the next, corresponding to changes in the interactions within the network. 0
Greenfield; Centers of Mind 120 Where a gestalt may be generating consciousness, we might expect shifting changes within a gestalt as further associations are triggered and new associations are made. 0
Greenfield; Centers of Mind 120 The process wherein gestalts are undergoing shifting changes as further associations are triggered and new associations made, might constitute the behavior or phenomena of thinking. 0
Greenfield; Centers of Mind 120 A determining feature of the size of the gestalts is the relative strength of the epicenter. 0
Greenfield; Centers of Mind 120 The stronger and more powerful the epicenter, the more neurons recruited in an assembly. 0
Greenfield; Centers of Mind 121 Plasticity needed for learning and memory entails changes that occur over hours or days and has a degree of permanence. 1
Greenfield; Centers of Mind 123 By Hebbian strengthening, neuronal contacts become more efficient. 2
Greenfield; Centers of Mind 123 Timeframe of Hebbian strengthening over hours. 0
Greenfield; Centers of Mind 124 Enhanced sensitivity of a group of cells linked to a persistent epicenter can enhance the recruiting power of an already-existing epicenter in fighting off a rival gestalt, a consciousness of something else. 1
Greenfield; Centers of Mind 124 Gestalts will only generate appreciable consciousness when they are sufficiently large. 0
Greenfield; Centers of Mind 125 Arousal might prime the formation of transient neuronal groups. 1
Greenfield; Centers of Mind 125 Arousal occurs when active neurons in the cortex are not in synchrony, producing a desynchronized EEG. 0
Greenfield; Centers of Mind 125 Neuronal connections among brain areas have long been seen by scientists as a key factor in consciousness. 0
Greenfield; Centers of Mind 126 Basic type of consciousness of the immediate world that Gerald Edelman terms primary consciousness. 1
Greenfield; Centers of Mind 128 Three published biological descriptions of consciousness, including those by Francis Crick and the physiologist Rudolfo Llinás focus on a particular loop between the cortex and the thalamus. 2
Greenfield; Centers of Mind 128 Not only does the thalamus project into the cortex, but the cortex projects back into the thalamus. 0
Greenfield; Centers of Mind 128 Cortex and the thalamus are in constant conversation. 0
Greenfield; Centers of Mind 128 Interplay among the cortex and the intermediate thalamus is very important. 0
Greenfield; Centers of Mind 129  Dennett's model of multiple drafts. 1
Greenfield; Centers of Mind 129 So much emphasis is placed on the loop between the cortex and the thalamus, we end up almost regarding the loop as the center of consciousness. 0
Greenfield; Centers of Mind 129 Francis Crick's (1984) searchlight of attention. 0
Greenfield; Centers of Mind 129 Attention is associated with synchronous discharge (oscillations ~40 Hz) of neurons in thalamocortical assemblies. 0
Greenfield; Centers of Mind 129 Francis Crick suggested there are many thalamocortical loops with the potential for generating consciousness. 0
Greenfield; Centers of Mind 130 Entrain the cortical neurons, for a time,    to be active in synchrony. 1
Greenfield; Centers of Mind 131 Crick claims that the all important factor is the degree of reverberation in the thalamocortical loop.    There must be a high degree of traffic, dialogue, shuttlecock, or whatever metaphor you like between the respective portions of the thalamus and the cortex. 1
Greenfield; Centers of Mind 131 Crick's idea is similar to Edelman's in that the emphasis is placed on vigor of communication between two regions in the brain,    what Edelman refers to as reentry. 0
Greenfield; Centers of Mind 131 Llinás has suggested    that it is the dialogue between the thalamus and the cortex    that generates subjectivity. 0
Greenfield; Centers of Mind 131 Internally generated cognitive states such as memories or dreams. 0
Greenfield; Centers of Mind 131 Crick deals mainly with visual awareness,    whereas Llinás is expressly concerned with consciousness that is independent of sensory inputs. 0
Greenfield; Centers of Mind 131 Llinás focuses on another part of the thalamus,    the nucleus reticularis,    which seems to be involved with more generalized states of arousal    during sleep and waking. 0
Greenfield; Centers of Mind 132 Llinás claims that since the brain is capable of autonomous rhythmicity,    which can occur independently of sensory inputs,    the sensory inputs are merely incidental,    an optional extra in consciousness. 1
Greenfield; Centers of Mind 132 Sensory inputs    are insufficient in themselves    to generate consciousness. 0
Greenfield; Centers of Mind 132 Consciousness can occur without sensory inputs. 0
Greenfield; Centers of Mind 133 A frequent result of head injury,    whether from internal stroke or external force,    is coma. 1
Greenfield; Centers of Mind 133 To be in a coma means that the brain is not working at all. 0
Greenfield; Centers of Mind 133 The reason a coma is so life-threatening    is that the mechanisms in the primitive brain stem,    which control basic life processes,    cease to function. 0
Greenfield; Centers of Mind 133 Heart has its own internal autorhythmicity. 0
Greenfield; Centers of Mind 134 Persistent vegetative state --    patients in this condition regain sleep wake cycles    and are able to regulate body temperature    and successfully fight infection. 1
Greenfield; Centers of Mind 134 Patients in persistent vegetative state    have reflex responses    whereby they withdraw from painful stimuli,    and they may even smile    or scream occasionally. 0
Greenfield; Centers of Mind 134 Patients in persistent vegetative state    have suffered cognitive death. 0
Greenfield; Centers of Mind 134 Persistent vegetative death    is frequently the final stage    of degenerative disorders    such as Alzheimer's disease. 0
Greenfield; Centers of Mind 134 Persistent vegetative state is important for understanding the nature of consciousness,    since it is a situation where there is arousal without consciousness. 0
Greenfield; Centers of Mind 137 Susan Greenfield's concentric theory suggests that consciousness is composed of two principal components:    (1) arousal;    (2) the formation of transient neuronal assemblies,    gestalts. 3
Greenfield; Centers of Mind 137 Consciousness is spatially multiple yet effectively single at any one time. 0
Greenfield; Centers of Mind 137 Consciousness is an emergent property of nonspecialized and divergent groups of neurons (gestalts) that is continuously variable with respect to, and always entailing, a stimulus epicenter. 0
Greenfield; Centers of Mind 137 Size of the gestalt, and hence the depth of prevailing consciousness, is a product of the interaction between the recruiting strength of the epicenter and the degree of arousal. 0
Greenfield; Centers of Mind 138 When an animal is aroused or threatened, groups of neurons fire in synchrony much more easily than in normal, more relaxed conditions. 1
Greenfield; Centers of Mind 138 Brainstem is the origin of the basic arousing system. 0
Greenfield; Centers of Mind 138 Brainstem neurons    project their axons over long distances    into the center of the brain    and into the cortex. 0
Greenfield; Centers of Mind 138 Conspicuous divergence of the pathways    of the brainstem neurons,    by which the oldest part of the brain in evolutionary terms influences the newest,    suggests a very diffuse and generalized form of communication. 0
Greenfield; Centers of Mind 139 Neural modulation    is a process for biasing the response of neurons    for relatively short periods of time,    ranging from seconds to hours,    without changing the response of the neurons permanently. 1
Greenfield; Centers of Mind 139 Neuromodulators are in a position to influence large populations of cortical cells    rather than transmit highly specific signals across discrete contacts. 0
Greenfield; Centers of Mind 139 Neuromodulators all emanate    from relatively small cell groups in the brainstem,    yet they project into the front of the brain    in a diffuse manner. 0
Greenfield; Centers of Mind 139 Modulatory neurons    are of critical importance to brain function    in that they are perfectly positioned to influence the formation of large gestalts    for the generation of consciousness. 0
Greenfield; Centers of Mind 140 A number of amine chemicals are associated with states of arousal.     Four of them are: (1) serotonin, (2) acetylcholine, (3) dopamine, (4) norepinephrine. 1
Greenfield; Centers of Mind 140 Serotonin is very important for sleep.    When it is injected into the spinal fluid,    dreamless sleep ensues. 0
Greenfield; Centers of Mind 140 Acetylcholine is also linked to sleep,    but in the opposite way.    The chemical contributes to the transition to and from dreaming states. 0
Greenfield; Centers of Mind 140 Increases in serotonin    are associated with a release away from consciousness,    whereas acetylcholine is linked to the time when we return back to awareness. 0
Greenfield; Centers of Mind 140 Dopamine may be associated with the enhanced general (as opposed to focused) arousal,    a distracted state where it is hard to settle on any one project and hard to sit still. 0
Greenfield; Centers of Mind 142 Increases in the release of norepinephrine    are associated with increases in alertness. 2
Greenfield; Centers of Mind 142 Hypothesis --    large gestalts generate consciousness,    and gestalts are large groups of neurons. 0
Greenfield; Centers of Mind 155 An epicenter must be some small aggregation of neurons. 13
Greenfield; Centers of Mind 155 The particular combination of connections    within the more hard-wired hub of cells of an epicenter    act to trigger the ripples    that encompass wider and wider populations of cells. 0
Greenfield; Centers of Mind 155 Strength of an epicenter    can be reflected in the intrinsic electrical activity    as well as the number of working interconnections entailed. 0
Greenfield; Centers of Mind 155 When an epicenter is strong,    because of either the strong physical qualities of a particular external object that impinges on the senses    or that that objects triggers certain extensive idiosyncratic associations,    we can imagine that a group of neurons would be either highly active    and/or had already developed extensive interconnections. 0
Greenfield; Centers of Mind 155 A highly active group of cells    with a large number of connections    would have a higher probability of recruiting into a gestalt still more neurons. 0
Greenfield; Centers of Mind 155 A weak epicenter    where the signaling was more intermittent    by way of fewer neurons. 0
Greenfield; Centers of Mind 155 The greater the initial number of neurons,    the greater the potential number of working connections    to other cells. 0
Greenfield; Centers of Mind 155 Once conscious of something,    it is harder    to become conscious of something else. 0
Greenfield; Centers of Mind 155 Synchronous cooperativity or ripples emanating from a particular epicenter, and the gestalt consequently created, make it harder to establish a rival gestalt. This is why it is harder to be awakened from dreams than from normal sleep. 0
Greenfield; Centers of Mind 157 Dennett's multiple drafts theory. 2
Greenfield; Centers of Mind 158 Penrose suggests that connections in the brain are like atoms in crystals in that they are in a constant state of change. Incessant quantum mechanical reorganization of neuronal connections.   [arcane and etherial] 1
Greenfield; Centers of Mind 159 Large neuronal assemblies (gestalts) can change remarkably rapidly.    Consciousness can shift seemingly instantaneously. 0
Greenfield; Centers of Mind 159 Rapid change in state    is typical of chaotic systems    where there is a systematic order    that is nonetheless so complex    that it defies analysis. 0
Greenfield; Centers of Mind 159 In systems as elaborate as gestalts,    where there are many influences    all interacting to produce a certain outcome,    a seemingly minor change can have large-scale consequences. 0
Greenfield; Centers of Mind 159 A change in consciousness    might arise if two potential gestalts    were rising simultaneously.    In this way it is possible that a rival gestalt    could curtail another gestalt. 0
Greenfield; Centers of Mind 160 Principles governing and regulating gestalt formation    include rapid and sensitive global changes    where new formations of neurons    can occur as a result of competing systems --    hence the genesis of new states of consciousness,    of original ideas,    of insights and imagination. 0
Greenfield; Centers of Mind 160 Principles of gestalt formation include the physical basis for generating false beliefs.    If new gestalts can be generated independently of the outside world    through internal competition,    they no longer are assured to have a direct correspondence and faithfulness    to the outside world, i.e., to reality. 0
Greenfield; Centers of Mind 161 Consciousness    is spatially multiple    yet effectively single at any one time. 0
Greenfield; Centers of Mind 161 Consciousness is an emergent property    of nonspecialized and divergent groups of neurons (gestalts)    that is continuously variable with respect to, and always entailing,    a stimulus epicenter. 0
Greenfield; Centers of Mind 161 Size of the gestalt    is a product of the interaction between    the recruiting strength of the epicenter    and the degree of arousal. 0
Greenfield; Centers of Mind 162 Neuronal assemblies    have many of the properties that gestalt theory requires --    highly dynamic and transient;    size dependent on strength of the epicenter;    size dependent on the strength of rival gestalts;    active selection of neurons according to their functional state    rather than passive recruitment of any nearby cells;    context dependent formation. 0
Greenfield; Centers of Mind 162 Interaction between    the recruiting strength of the epicenter    and the degree of arousal    could determine the quality and quantity of consciousness    we are experiencing at any one time. 0
Greenfield; Centers of Mind 162 Consciousness    is spatially multiple    but continuously variable. 0
Greenfield; Centers of Mind 162 Consciousness is an emergent property. 0
Greenfield; Centers of Mind 164 Neurosurgeon Wilder Penfield (1963) exposed brain areas of conscious patients with intractable epilepsy; he stimulated parts of the cortex and reported the resultant effects on awareness. The stimulation evoked memories but lacked specific space-time reference points and were reported as seeming dreamlike. 0
Greenfield; Centers of Mind 165 Dreams were postulated to be the result of mimimal gestalts. 0
Greenfield; Centers of Mind 165 Demonstrations of Penfield could be explained as the stimulation of minimal gestalts where, as in dreams, there is no clear logic, no continuity, but rather, a disembodied scene. 0
Greenfield; Centers of Mind 165 Failure of the stimulation most frequently to produce any affects at all might simply be that not enough neurons were recruited or that a stimulating electrode was in a poor site to trigger an appropriate epicenter. 0
Greenfield; Centers of Mind 165 Stimulation of the same site could give different results. 0
Greenfield; Centers of Mind 165 Same memory could be generated from different stimulation sites. 0
Greenfield; Centers of Mind 165 Small, minimal gestalts, produced artificially by Penfield but more normally during dreaming state, could be regarded as scraps of consciousness torn from seemingly cohesive fabric of our awareness. 0
Greenfield; Centers of Mind 170 Daydreaming is an extreme example of consciousness dominated by highly complex cognitive epicenters, when sensory input is minimal. 0
Greenfield; Centers of Mind 170 How easy it is to walk home alone, unaware of the route, so involved in our own inner fantasy that we are effectively blind and deaf to all around us. 0
Greenfield; Centers of Mind 171 To generate a deep or heightened consciousness, we need a powerful epicenter. 0
Greenfield; Centers of Mind 171 A powerful epicenter could be cognitive, such as an all-pervading worry, or it could be external and strong, due to an intrinsic brightness or loudness of an outside object or to a heightened arousal. 0
Greenfield; Centers of Mind 171 We are frequently highly conscious of very minimal stimuli, such as a whisper or a light touch on the skin. 0
Greenfield; Centers of Mind 171 Weakness of a stimulus should not be assessed on its own but, rather, in the light of signal-to-noise ratio. 0
Greenfield; Centers of Mind 171 If someone whispers in a library, we are immediately aware of it because there is no other sound, as compared with a whisper at a cocktail party. 0
Greenfield; Centers of Mind 171 If there is a situation relatively devoid of powerful incoming sensory stimulus, such as being alone in a house at night, then even the smallest creak on the stairs may dominate our consciousness. 0
Greenfield; Centers of Mind 171 A weak stimulus can also be powerful if it triggers a large gestalt, either because it has strong cognitive associations and/or because arousal is high.  At a party, a whisper or small gesture of a lover may have immediate significance, even in a crowd of people. 0
Greenfield; Centers of Mind 171 Awareness of pain is highly variable and may be attributable to different degrees and manners of subconscious associations, generating gestalts of varying sizes. 0
Greenfield; Centers of Mind 172 Potent painkiller morphine and the brain's own equivalent enkephalin might be involved in restricting the formation of gestalts. 0
Greenfield; Centers of Mind 172 Reports of the analgesic effect of morphine are that the pain is still present, but that it no longer matters to the patient; it no longer has significance. We might say that the pain no longer triggers extensive associations, as it would in normal sized gestalts. 0
Greenfield; Centers of Mind 172 For someone experiencing pain, the brain would be dominated by a larger than usual gestalts. 0
Greenfield; Centers of Mind 172 As gestalts start to grow larger than normal, A sufferer might be more deeply conscious. 0
Greenfield; Centers of Mind 172 Size of a gestalt has a direct relation to depth of consciousness. 0
Greenfield; Centers of Mind 172 Large gestalt implies a sustained period of deep consciousness around a particular epicenter that triggered many associations. 0
Greenfield; Centers of Mind 172 Small gestalt implies a shallow consciousness of short duration, centered around an epicenter where associations were sparse or where there was insufficient time for many associations to be made. 0
Greenfield; Centers of Mind 172 Examine whether different pathologies have a common problem of neuronal gestalts.  Should speak of factors rather than causes, because the formation of gestalts is an interactive process with the environment. 0
Greenfield; Centers of Mind 173 Small gestalts occur either in the case of a weak epicenter (as in dreams) or where too many gestalts compete (as an over arousal). 0
Greenfield; Centers of Mind 173 In dreams and in over arousal, there are no strong, continuous, associated links from one small gestalt to the next; ripples never extend far enough to recruit another epicenter cognitively. 0
Greenfield; Centers of Mind 173 When awake, a person who has only small gestalts, would experience an abrupt shift in consciousness governed by the caprices of the external sensory world as it floods the brain. 0
Greenfield; Centers of Mind 173 Gestalts might overlap just enough to cause tenuous connections in the flow of consciousness.  Connections might be sparser, more  obscure, less obvious, trains of thought that are illogical, just like dreams. 0
Greenfield; Centers of Mind 173 Small gestalts may be associated with less concern with pain. 0
Greenfield; Centers of Mind 173 Subjective sensation of pain is metaphorical, depending on the variable number associations the painful stimulus triggers. 0
Greenfield; Centers of Mind 173 If pain associations are sparse, the reaction to pain may be similar to that of the morphine taker, for whom pain is no longer significant and for whom consciousness is often reported as dreamlike. 0
Greenfield; Centers of Mind 173 Small gestalts, where the associations arising from an epicenter are limited, would imply that memory for past events will not be strong. 0
Greenfield; Centers of Mind 173 If a person is unable to form large gestalts, the chances of forming a new gestalt by focusing on a new epicenter would be maximized if he moves about, thereby increasing the variety of novel sensory cues. 0
Greenfield; Centers of Mind 174 Someone with a small gestalts, might be restless, with incessant movement combined with the inability to concentrate, think logically, or form abstract concepts. 0
Greenfield; Centers of Mind 174 Someone with small gestalts might have poor long-term memory. 0
Greenfield; Centers of Mind 174 Someone with small gestalts would have an active interest in their surroundings and a breezy attitude toward pain.  0
Greenfield; Centers of Mind 174 For someone with small gestalts, life would be lived in the present as a continuous reaction to the outside world. 0
Greenfield; Centers of Mind 174 Schizophrenia is a type of psychosis in which there is often a departure from reality. 0
Greenfield; Centers of Mind 174 Two types of schizophrenia have been proposed (1980) as Type I and Type II. 0
Greenfield; Centers of Mind 174 Type I, or acute, schizophrenia may not last indefinitely and is characterized by abnormal thoughts and actions, hence positive signs. In Type I schizophrenia there is motor restlessness, where the same actions is repeated over and over outside of its normal context. 0
Greenfield; Centers of Mind 174 Type II, or chronic, schizophrenia last indefinitely and is characterized by what the patient does not do,  hence negative signs. Patients turn inward, seemingly oblivious to all around them. 0
Greenfield; Centers of Mind 174 Negative-symptom schizophrenia (Type II) is in itself indistinguishable from depression. 0
Greenfield; Centers of Mind 176 In Type I schizophrenia there is motor restlessness, where the same action is repeated over and over outside of its normal context. 0
Greenfield; Centers of Mind 176 Schizophrenics use a higher turnover of sensory epicenters. 0
Greenfield; Centers of Mind 177 Normal people, in contrast to schizophrenics, form fewer and bigger gestalts, thus allowing them to have more abstracted and longer lasting lines of thought and deeper consciousness. 0
Greenfield; Centers of Mind 178 In schizophrenia, with small gestalts; glowing, brilliant objects might well be construed as proof of superhuman godlike perception, which is a frequent schizophrenic delusion. 0
Greenfield; Centers of Mind 178 Dreaming is describable in terms of small gestalts. 0
Greenfield; Centers of Mind 178 World of the schizophrenic is not that much different from our world of dreams or, rather, nightmares. 0
Greenfield; Centers of Mind 178 Illogical associations, the unquestioned leaps from one scenario to another, and a lack of logic and space-time references would all be consistent with the distorted perception describable in terms of small gestalts. 0
Greenfield; Centers of Mind 178 Many of the signs and symptoms of Type I schizophrenia can be described in terms of abnormally small gestalts. 0
Greenfield; Centers of Mind 180 Schizophrenics cannot follow a chain of thought, but just repeat words or ideas -- a sign of weak associative connections amounting to small gestalts. 0
Greenfield; Centers of Mind 181 Consciousness deepens gradually as larger gestalts are able to form and develop more neuronal connections. 0
Greenfield; Centers of Mind 181 Children would be expected to have small gestalts. 0
Greenfield; Centers of Mind 183 Large gestalts would be favored by increases in serotonin. 0
Greenfield; Centers of Mind 184 A widespread treatment of depression is to administer drugs that increase the availability of serotonin. 0
Greenfield; Centers of Mind 184 Depression is associated not with a paucity of serotonin but with a target receptors being too sensitive.  By bombarding these receptors with massive amounts of drug-induced serotonin, after about 10 days they become far less sensitive. 0
Greenfield; Centers of Mind 184 When receptors to serotonin are less sensitive, serotonin is less efficient, and so large gestalts are not formed so readily.  The all-embracing despair requiring a large gestalt is therefore no longer possible. 0
Greenfield; Centers of Mind 184 Small gestalts would be favored if the action of serotonin was blocked. 0
Greenfield; Centers of Mind 185 Hallucinogenic drug LSD works in the brain by reducing the effectiveness of serotonin. 0
Greenfield; Centers of Mind 185 LSD could be said to cause the formation of small gestalts, equivalent to those postulated as characterizing schizophrenia. 0
Greenfield; Centers of Mind 185 The elderly in certain respects resemble those with short-term memory deficit and depressives. 0
Greenfield; Centers of Mind 185 Elderly do not move around much; they are very sensitive to pain and illness; and they tend to live in the past. 0
Greenfield; Centers of Mind 186 Large gestalt would furnish the infrastructure for intense sensation of pain. 0
Greenfield; Centers of Mind 186 Brain and environment are in constant dialogue. 0
Greenfield; Centers of Mind 186 Small children have little sense of time passing; they are living in the present, where every day seems like an eternity. 0
Greenfield; Centers of Mind 186 For the elderly, life can hurdle by, and distant events can seem like only yesterday. 0
Greenfield; Centers of Mind 186 Time perceptions can perhaps be viewed in terms of gestalt formation. 0
Greenfield; Centers of Mind 186 With a schizophrenic or a child, time is perceived as passing slowly. 0
Greenfield; Centers of Mind 186 Prolonged concentration leaves us with the feeling that the morning has rushed by. 0
Greenfield; Centers of Mind 186 If there are no gestalts formed and no consciousness at all, as in anesthesia or sleep, time will pass most quickly, almost instantaneously. 0
Greenfield; Centers of Mind 186 The more rapid the turnover of gestalts, the more slowly time seems to pass. 0
Greenfield; Centers of Mind 187 Time perception might indicate to us the speed or the turnover of gestalt formation. 0
Greenfield; Centers of Mind 187 Time perception, and its correspondence with groups of small and large gestalts, suggest a means for us to tell how quickly our own gestalts might be changing in our brains. 0
Greenfield; Centers of Mind 187 Size of gestalt might determine the type of consciousness experienced. 0
Greenfield; Centers of Mind 187 If the gestalts were of, for pathological reasons, dramatically diminished, this could be the situation in Type II schizophrenia in which the symptoms are negative and insensitive to medication. 0
Greenfield; Centers of Mind 187 IN Type II schizophrenia, the patient does not know who he is nor where he is; his consciousness sinks down toward the bottom of the continuum, a scenario of diminishing gestalts. 0
Greenfield; Centers of Mind 187 Degeneration of the brain in Alzheimer's disease is very similar in signs and symptoms to Type II schizophrenia. 0
Greenfield; Centers of Mind 188 Contribution of acetylcholine to consciousness and maintaining moderate levels of arousal is particularly relevant in view of the fact that in Alzheimer's disease there is a marked deficiency in acetylcholine. 0
Greenfield; Centers of Mind 188 In initial stages of Alzheimer's disease, with a degeneration prior to complete loss of all gestalt's, we might expect that the  patient would go through a period resembling that of schizophrenia or a childhood profile of small gestalts. 0
Greenfield; Centers of Mind 188 In senile dementia, the patient is frequently restless and active, in accordance with the small gestalt profile. 0
Greenfield; Centers of Mind 188 If we think of gestalt size and thus consciousness as a continuum, we can easily imagine that our momentary states of awareness lie between large and small gestalt type profiles as we live each day, progressing along a line of epicenters.  There will be times of deep reflection interspersed with moments when we open up to the vivid sensuality of the outside world. 0
Greenfield; Centers of Mind