Rodolfo
Llinás; Mind-Brain Continuum |
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Chapter |
Page |
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Topic |
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Llinás
& Paré; Brain Modulated by Senses |
4 |
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Nervous system
is primarily self activating and capable of generating a cognitive
representation of the external
environment even in the absence
of sensory input, as
for example in dreams. |
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Llinás
& Paré; Brain Modulated by Senses |
5 |
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Emotions are
examples of internally generated intrinsic events that are premotor templates in primitive forms. |
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1 |
Llinás
& Paré; Brain Modulated by Senses |
5 |
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Within each modality, sensory inputs are processed by activity in a constellation of cortical regions
that analyze specific aspects of the stimuli. |
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0 |
Llinás
& Paré; Brain Modulated by Senses |
5 |
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Central nervous system must have developed
over evolutionary time
as a neuronal network that initially mediated simple reflex relations between sensory-motor connectivity. |
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0 |
Llinás
& Paré; Brain Modulated by Senses |
6 |
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Dreaming and
wakefulness are so similar from electrophysiological
and neurological points of view that wakefulness may be described as a dreamlike
state modulated by sensory input. |
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1 |
Llinás
& Paré; Brain Modulated by Senses |
7 |
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Several noninvasive
technologies have been developed that allow partial window into human brain function. Such techniques as positron emission tomography (PET) and magnetic
resonance imaging (MRI)
are quite powerful for visualizing localized
activity in certain
areas of the brain during particular functional states. |
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1 |
Llinás
& Paré; Brain Modulated by Senses |
7 |
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PET and MRI images of activity may be correlated to visual inputs,
voluntary movements, and premotor potentials, and can be
accurately isolated at the microscopic level with an accuracy of 1 -- 3 mm. However, PET
and MRI methods are quite limited in the
time domain. |
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0 |
Llinás
& Paré; Brain Modulated by Senses |
7 |
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In a research environment, magnetoencephalography (MEG) can measure human brain function with a temporal
resolution comparable
to the central nervous system itself. Frequency response of the MEG
instruments -- 1 kHz
-- ensures that the electrical events coexisting with cognition may be measured
in real time. |
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0 |
Llinás
& Paré; Brain Modulated by Senses |
7 |
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Experiments using magnetoencephalography (MEG) has demonstrated that the coherence
and oscillations at 40 Hz
may be centrally
related to cognition. |
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0 |
Llinás
& Paré; Brain Modulated by Senses |
7 |
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In alert subjects, continuous 40-Hz oscillations can be recorded over large areas
of the surface of the head. These oscillations are not in phase, but exhibit a 12- to 13-ms phase
shift between the rostral and caudal
parts of the brain. |
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0 |
Llinás
& Paré; Brain Modulated by Senses |
9 |
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On presentation of sensory stimuli, 40-Hz oscillations show phase locking, which is proposed to
be related to cognitive processing and to the temporal binding of sensory stimuli. |
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2 |
Llinás
& Paré; Brain Modulated by Senses |
9 |
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To investigate the role of coherent 40-Hz oscillations in sensory segmentation and binding, MEG recordings were made
from the auditory cortex. Based on a power spectral analysis, we define
the 40-Hz response
produced by a single stimulus as a 2.5-oscillation
cycle,
demonstrating 2.5 oscillations at 40 Hz. |
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Llinás
& Paré; Brain Modulated by Senses |
12 |
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Experimental observations have
concluded that sensory information is processed in discrete time segments as low as 12 ms. |
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3 |
Llinás
& Paré; Brain Modulated by Senses |
12 |
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Whereas the 12.5
ms time for the quantum
of cognition has been determined psychophysically, another very distinct measurement of the phase shift of 40-Hz oscillatory
activity over the human cortex has a 12.5-ms duration as well. |
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0 |
Llinás
& Paré; Brain Modulated by Senses |
12 |
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40 Hz oscillations are present at many levels in the CNS, olfactory
bulb, specific and nonspecific
thalamic nuclei, reticular thalamic
nucleus, and neocortex. |
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0 |
Llinás
& Paré; Brain Modulated by Senses |
13 |
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Damage to the nonspecific thalamus produces deep
disturbances of consciousness, whereas damage to specific systems produces
loss of the particular modality. |
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1 |
Llinás
& Paré; Brain Modulated by Senses |
14 |
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Specific thalamocortical
system is viewed as encoding specific sensory and motor information through the resonant
thalamocortical system specialized to receive such inputs. |
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1 |
Llinás
& Paré; Brain Modulated by Senses |
14 |
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Activity in
the thalamocortical system would tend to oscillate near 40 Hz, and activity in the specific thalamocortical system could easily be recognized over the cortex by this oscillatory characteristic. |
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Llinás
& Paré; Brain Modulated by Senses |
14 |
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Specific thalamocortical system
would provide the content that relates to the external world, and the nonspecific system would give rise to the temporal
conjunction, or the context that would together generate a single cognitive experience. |
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0 |
Llinás
& Paré; Brain Modulated by Senses |
14 |
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Perception
at a given moment is represented by a small
percentage of coherently
oscillating cellular elements over the whole thalamocortical system. [Edelman's dynamic
core] |
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Damasio; Making Images |
19 |
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Making Images and Creating
Subjectivity |
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5 |
Damasio;
Making Images |
20 |
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It appears that the temporally coordinated activity of
the varied early cortices, and other subcortical stations with which they are interconnected, yields the essence of what we call an image. |
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1 |
Damasio; Making Images |
20 |
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Early sensory cortices are the critical base for processes of image making. |
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Damasio; Making Images |
20 |
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Damage to higher-order association cortices, which are located outside
of the early sensory region, does not preclude the making of images. |
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Damasio;
Making Images |
20 |
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Hypothesized that the early sensory cortices of each modality construct, with the assistance of structures in the thalamus and the colliculi, neural representations that are the basis for images. |
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0 |
Damasio;
Making Images |
20 |
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Temporally coordinated activity of varied early cortices and of the subcortical stations with
which they are interconnected yields the essence
of what we call an image. |
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0 |
Damasio;
Making Images |
20 |
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An important characteristic of images is that they have spatially and temporally organized patterns, and in the case
of visual, somatosensory, and auditory images, those patterns are topographically organized. |
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0 |
Damasio;
Making Images |
20 |
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Topographic representations can be committed to memory in the form of nontopographically organized dispositional representations,
and can be stored in dormant form in both cortical regions or subcortical nuclei. |
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0 |
Damasio;
Making Images |
20 |
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Subsequent reactivation of those dormant
dispositional representations, followed by signaling from their storage sites back to early sensory cortices, can regenerate
topographically organized representations. |
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0 |
Damasio;
Making Images |
20 |
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Retroactivation process uses the rich connectional patterns of feed-forward and feedback that characterize the architecture
of cortical regions and subcortical
nuclei. |
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0 |
Damasio; Making Images |
20 |
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Topographic representations can arise in turn as a result of signals external to the brain
in the perceptual process,
or in the process of recall from
signals inside the brain, coming from memory
records held in dispositional
representation form. |
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0 |
Damasio; Making Images |
21 |
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Convergence zones receive convergent signals and originate divergence signals toward the sites from which convergent
signals came. |
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1 |
Damasio; Making Images |
21 |
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Convergence zones are located throughout association
cortices and subcortical
nuclei. |
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0 |
Damasio; Making Images |
23 |
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Conceptualize the self as a collection of images about the most invariant aspects of our organism and its interactions. |
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2 |
Damasio;
Making Images |
23 |
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Core components of the
self concern body
structure
(i.e. viscera, musculoskeletal frame) and fundamentals of one's identity (i.e. usual activities, preferences, physical and human relationships,
etc.) |
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Damasio;
Making Images |
25 |
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An object that is being represented, an organism responding to the object of representation, and a description of the organism in the process of changing in response to the object -- are held simultaneously in working memory and are placed
side-by-side
on rapid interpolation in early sensory cortices. |
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2 |
Damasio; Making Images |
25 |
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Subjectivity
would emerge when the
brain is simultaneously producing not just images of an entity, of self and of organism responses, but also another
kind of image:
that of an organism in the act of perceiving and responding to an entity. |
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Ramachandran;
Illusions of Body Image |
29 |
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Our behavior is mostly governed by a cauldron of
emotions and motives of which we are largely unconscious. Incarnations of this idea include such
phenomena as blindsight,
or the elicitation of changes in skin conductance in patients who have no conscious
recognition of faces. |
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4 |
Ramachandran;
Illusions of Body Image |
29 |
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Anosognosia:
the vehement denial of paralysis in some patients who have suffered a
right hemisphere stroke. |
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Ramachandran;
Illusions of Body Image |
42 |
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The left
hemisphere creates a model of reality. If confronted with some new information that does not fit the model, the left
hemisphere tends to deny, repress, or confabulate. |
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13 |
Ramachandran;
Illusions of Body Image |
42 |
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The right
hemisphere plays "devil's
advocate" for unrealistic models and forces the organism to revise the entire model. |
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0 |
Ramachandran;
Illusions of Body Image |
43 |
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In an anosognosia patient, the left
hemisphere is doing all the confabulation and denial. The right
hemisphere is not
available to
force a paradigm
shift in response to conflicting information. Thus a delusional
trap with continued confabulation. |
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1 |
Ramachandran;
Illusions of Body Image |
53 |
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Humor
typically involves taking someone along the garden
path of expectation so that the left hemisphere constructs a story
or model and then a sudden
unexpected twist is introduced to generate a paradigm shift, i.e. a completely new model is invoked to explain the same data. |
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10 |
Ramachandran;
Illusions of Body Image |
53 |
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The twist in the humor
episode has to be a novel but inconsequential. Thus, we may regard humor as a response to inconsequential anomaly. |
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0 |
Ramachandran;
Illusions of Body Image |
55 |
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Physicists refer to the "edge of chaos" in
dynamical systems -- the emergence of "complexity" at the boundary between stability and chaos. |
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2 |
Ramachandran;
Illusions of Body Image |
56 |
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Domain specificity is not restricted to anosognosia, it shows up in many
areas of neurology. |
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1 |
Ramachandran;
Illusions of Body Image |
56 |
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What are we to make of selective loss of vegetable names with sparing of fruits? Or the loss of an animate object names, but not of inanimate ones? Such findings pose a serious challenge for any theory of knowledge representation in the brain. |
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0 |
Merzenich;
Neural Representations |
61 |
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The cerebral
cortex is best understood in terms of ensembles of neurons that are used
to represent the perceived world. |
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5 |
Merzenich;
Neural Representations |
62 |
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The cerebral
cortex is not a passive machine that waits for
inputs, but an active, dynamic system that constructs
and maintains
our complex internal
world through its activities. |
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1 |
Merzenich;
Neural Representations |
62 |
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All perceptions, choices, actions, and representations take place against the backdrop of an internal context that is formed from experience and is maintained with the cortical system. |
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0 |
Merzenich;
Neural Representations |
62 |
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The cortex represents the world through the use of interconnected networks of neurons or neuronal assemblies. |
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0 |
Merzenich;
Neural Representations |
62 |
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Coding in
the cortex is probably relational rather than strictly combinatorial, meaning that the
system uses relations
between elements and ensembles to establish reliable and flexible
representations. |
|
0 |
Merzenich;
Neural Representations |
63 |
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The cortex is a dynamic system in which all representations occur against a backdrop of a continuing, internally generated content. |
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1 |
Merzenich;
Neural Representations |
64 |
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The internal context supplied by the nervous system includes such things
as attention,
expectancy, mental
semblancy, planning, emotion,
and
motivation; and it determines the
qualities of our awareness of an object, our choices of how to act, and our actions themselves. |
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1 |
Merzenich;
Neural Representations |
64 |
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Object and context hold equally important causal roles that lead to perception and onward to action, and each is
represented by continuing activity patterns in the brain. |
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0 |
Merzenich;
Neural Representations |
65 |
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Research studies have shown that
important aspects of neural representation take place
only through the combined actions or interactions of neuronal ensembles, and not by the activities of individual neurons alone. |
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1 |
Merzenich;
Neural Representations |
65 |
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Representation ensembles span cortical and subcortical systems, with objects represented simultaneously across broadly separated cortical areas. |
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0 |
Merzenich;
Neural Representations |
66 |
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Cortical neuronal
representations must be understood as being relational rather than
merely combinatorial. |
|
1 |
Merzenich;
Neural Representations |
66 |
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The significance of a given neuron's signal can only be interpreted
by the brain in terms of its relation to the activity of other neurons, not with respect to a fixed
system whereby each neuron indicates a distinct feature. |
|
0 |
Merzenich;
Neural Representations |
68 |
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Given the short time constants governing synaptic plasticity in the cortex (milliseconds to tens of milliseconds), temporally coincident, coherent inputs are highly effective in driving representational changes. |
|
2 |
Merzenich;
Neural Representations |
69 |
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At lower
system levels,
the cortical areas are occupied by topographically ordered
representations
of the retina, cochlea, or skin. During learning, it is possible for large,
continuous, strongly
interconnected neuronal ensembles to emerge and represent behaviorally important stimuli. |
|
1 |
Merzenich;
Neural Representations |
70 |
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The majority
of input to cortical neurons comes from other neurons in the local
network neighborhood. |
|
1 |
Merzenich;
Neural Representations |
70 |
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Strongly correlated afferent bombardment leads to changes in the connections between neighboring neurons, thereby creating cooperating neuronal groups
that, because of their strengthened, positive interconnections, appeared to discharge as members of a neuronal syncitium.. |
|
0 |
Merzenich;
Neural Representations |
71 |
|
The generation of progressively
more coincident firing
across neuronal
assemblies as a consequence of learning, amplifies representational
power and effects, both locally, and within the projection
targets of a reorganizing
cortical area. |
|
1 |
Merzenich;
Neural Representations |
71 |
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Modulatory Control of Cortical
Plasticity |
|
0 |
Hickmott;
Neurotransmitter Regulation of Synaptic Plasticity |
83 |
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Neurotransmitter Receptor
Regulation and Its Role in Synaptic Plasticity and Stabilization |
|
12 |
Hickmott;
Neurotransmitter Regulation of Synaptic Plasticity |
87 |
|
In 1949
Donald Hebb proposed a "neurophysiological
postulate" of learning that states that presynaptic and postsynaptic cells that fire nearly synchronously tends to increase the efficacy of their connections. |
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4 |
Hickmott;
Neurotransmitter Regulation of Synaptic Plasticity |
90 |
|
For many
regions of the brain, during normal development, activation of the NMDA receptor is a necessary component
of the activity-dependent mechanism that selectively prunes synapses and tunes developing connections. |
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3 |
Singer; Neuronal Synchronization |
104 |
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The essential advantage of the dynamic, self organizing binding
process is that
individual cells can bind at different times with different partners, when input constellations change. |
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14 |
Singer; Neuronal Synchronization |
106 |
|
During the formation of functionally coherent
assemblies,
the discharges of neurons undergo a specific temporal
patterning
so
that cells participating in the encoding of related contents eventually come
to discharge in synchrony. |
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2 |
Singer; Neuronal Synchronization |
106 |
|
The temporal patterning of neurons is thought to be based on a self-organizing process that is mediated by a highly selective network of reentrant connections. |
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0 |
Singer; Neuronal Synchronization |
109 |
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Distributed groups of neurons can engage in synchronous activity. |
|
3 |
Singer; Neuronal Synchronization |
109 |
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Temporally coded assemblies of neurons require that the probabilities with which distributed cells synchronize their responses should
reflect some of the Gestalt criteria applied in perceptual grouping. |
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0 |
Singer; Neuronal Synchronization |
113 |
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Individual cells can change partners with which they synchronize when stimulus configurations change. |
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4 |
Singer; Neuronal Synchronization |
114 |
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In mammals, cortico-cortical connections develop mainly postnatally and attain their full specificity through an activity-dependent
selection process. |
|
1 |
Singer; Neuronal Synchronization |
125 |
|
It seems likely that neural activation
patterns (assemblies)
reaching the threshold of conscious awareness must be sufficiently organized, i.e. coherent. |
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11 |
von der
Malsburg; Binding Problem |
133 |
|
The physical
quantities constituting long-term memory or synaptic strengths. |
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8 |
von der
Malsburg; Binding Problem |
136 |
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Dynamic Link Architecture |
|
3 |
von der
Malsburg; Binding Problem |
137 |
|
Two aspects
of neuron signals in
the brain: (1) rate or mean frequency of firing, (2) fine temporal signal structure, which is evaluated in terms of correlations among sets of cells. |
|
1 |
von der
Malsburg; Binding Problem |
137 |
|
If, during a
time interval, the signals
on a set of neurons are significantly
correlated, the set is interpreted as being bound during that interval. |
|
0 |
von der
Malsburg; Binding Problem |
137 |
|
There is experimental evidence
for the existence in the nervous system of temporal
signal structure of appropriate nature to encode binding by temporal synchrony. |
|
0 |
von der
Malsburg; Binding Problem |
137 |
|
Correlations
involving just two neurons cannot play a central role because binary correlations are too easily drowned in the noise of
accidental coincidences. Therefore, the significant
correlations will be those involving larger numbers of neurons, perhaps near-simultaneous spikes on fifty neurons, which can easily be recognized as being statistically significant. |
|
0 |
von der
Malsburg; Binding Problem |
139 |
|
Cortical neural signals have a very pronounced stochastic structure, and nervous tissue is evidently designed
to create and preserve it. An assumption of statistical
independence of signals therefore must be faulty, and strong
signal correlations must be present in the brain. |
|
2 |
von der
Malsburg; Binding Problem |
140 |
|
Temporal bandwidth of neural signals is severely limited. It is not possible within short periods
of time to express
complicated multilevel binding structures in terms
of signal correlations. |
|
1 |
von der
Malsburg; Binding Problem |
140 |
|
Rapid synaptic modification -- synapses are characterized by two quantities, T and J,
where T is the conventional permanent synaptic
weight; and J is the momentarily effective
strength of a synapse. The parameter J can vary on a rapid time scale between zero and a maximum determined by T. |
|
0 |
von der
Malsburg; Binding Problem |
140 |
|
Forceful activity events can modify synapses in a small fraction of a second, perhaps a few milliseconds. When there is no
further activity in the two
cells connected by a synapse, J slowly returns to its resting
value, with the time constant of short-term
memory. |
|
0 |
von der
Malsburg; Binding Problem |
141 |
|
Two central hypotheses of dynamic link architecture: (1) binding by signal correlations, and
(2) short-term synaptic modification. |
|
1 |
von der
Malsburg; Binding Problem |
141 |
|
Signal correlations come to express the patterns of connections in the
circuit, i.e., the underlying causal structure of the nervous system. |
|
0 |
von der
Malsburg; Binding Problem |
142 |
|
Neurons are coincidence detectors and are superbly sensitive to signal correlations. |
|
1 |
von der
Malsburg; Binding Problem |
142 |
|
A correlation
pattern can selectively activate receiving
circuits of appropriate
structure.
In the simplest case this is possible if the circuit
that receives the pattern is isomorphic to the circuit that created it. |
|
0 |
von der
Malsburg; Binding Problem |
142 |
|
Whereas in classic neural
networks, neurons do not pay attention to fine signal
structure, in the dynamic
link architecture the
incoming signals have to be correlated in time. |
|
0 |
von der
Malsburg; Binding Problem |
142 |
|
A given set
of neurons
can support a large number of activity patterns that differ only in their fine temporal
structure. |
|
0 |
von der
Malsburg; Binding Problem |
142 |
|
The cognitive system of dynamic
link architecture is based upon "synfire"
chains -- sets ("pools") of neurons,
each one connected nearly all-to-all with the next pool. The synfire
chain can be traversed
by an activity process in which all the cells in a pool fire simultaneously and thus succeed in firing the
cells in the next pool simultaneously. |
|
0 |
von der
Malsburg; Binding Problem |
142 |
|
Each neuron
can participate in many synfire chains and even several times in the same chain. Synfire chains are proposed as the basic building blocks of a compositional cognitive system. |
|
0 |
von der
Malsburg; Binding Problem |
142 |
|
Signal correlations are evaluated by synapses by modifying their dynamic weight. The interaction between signal correlations and synaptic dynamics has the form of a positive feedback
loop. This feedback loop is the basis for a system
of rapid network self-organization. |
|
0 |
von der
Malsburg; Binding Problem |
142 |
|
Signal correlations act back on the network and modify
its structure by rapid
synaptic modification. This leads to a run-away situation that comes to a
halt when a dynamic network connectivity pattern is reached in which the signal
structure and the connectivity
structure are consistent with each other. |
|
0 |
Logothetis,
Object Recognition in Primates |
147 |
|
Recognition and Representation
of Visual Objects in Primates |
|
5 |
Logothetis,
Object Recognition in Primates |
147 |
|
Nonlinear interpolation among stored orthographic or
perspective views that can be determined on the
basic of geometric features or material properties of the object. |
|
0 |
Logothetis;
Object Recognition in Primates |
160 |
|
The
inferior temporal area (IT) is composed of the large region of cortex extending from just anterior to the inferior occipital sulcus to just posterior to the temporal pole, and from the fundus of the superior temporal sulcus
to
the fundus of the occititotemporal sulcus. |
|
13 |
Logothetis;
Object Recognition in Primates |
160 |
|
Lesion studies in monkeys showed that damage to IT spares low-level
visual tasks, such as orientation
discrimination,
but disrupts pattern
perception and recognition. |
|
0 |
Logothetis;
Object Recognition in Primates |
160 |
|
Cells in the inferior temporal
area (IT) have large receptive fields that almost always include the fovea,
and most of the cells are selective for stimulus attributes such as size,
color, orientation, and direction of movement. |
|
0 |
Logothetis;
Object Recognition in Primates |
161 |
|
Shape is a prevailing stimulus
feature in IT cortex. The IT neurons respond in a selective manner to the
shape of various natural or humanmade objects. |
|
1 |
Logothetis;
Object Recognition in Primates |
161 |
|
The most striking class of highly selective cells in IT are those responding to the sight of faces. |
|
0 |
Logothetis;
Object Recognition in Primates |
161 |
|
Presenting different
views or
parts of the face in isolation revealed that the neurons may respond selectively to face views, features, or subsets of features. |
|
0 |
Logothetis;
Object Recognition in Primates |
163 |
|
A small
percentage of neurons, although often firing with a rate of between 5 and
20 Hz, could not be driven by any of the stimuli
used in these experiments. |
|
2 |
Logothetis;
Object Recognition in Primates |
165 |
|
Some IT neurons were maximally sensitive to the front view of the
face,
and their response fell off as the head was rotated into the profile view; others were sensitive to the profile view with no reaction to the front view of the face. |
|
2 |
Logothetis;
Object Recognition in Primates |
166 |
|
The study revealed a total of five cell types in the superior temporal sulcus, each maximally
responsive to one view of the head. |
|
1 |
Logothetis;
Object Recognition in Primates |
166 |
|
The five types of cells were separately tuned for full face, profile, back of the head, head up, head down. |
|
0 |
Logothetis;
Object Recognition in Primates |
166 |
|
Most of these head-sensitive neurons
were 2 to 10
times more sensitive to faces than to simple geometrical stimuli
or three-dimensional
objects. |
|
0 |
Logothetis;
Object Recognition in Primates |
166 |
|
The study found cells in the IT cortex of infant monkeys that had responses selective for shape, faces, geometrical patterns, and color. |
|
0 |
Logothetis;
Object Recognition in Primates |
166 |
|
At least some
of the neurons that are selective to highly complex patterns are available to the recognition
system
even at the earliest developmental stage of the visual system. |
|
0 |
Logothetis;
Object Recognition in Primates |
169 |
|
Only a small
number of object views have to be stored to achieve the perceptual invariance that biological visual systems exhibit in everyday life. |
|
3 |
Logothetis;
Object Recognition in Primates |
169 |
|
A small
population of neurons in
inferior temporal cortex responds selectively to individual members of the object classes. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
177 |
|
Taste can be
simplified to four primitive chemical categories, and responses are monotonic to concentration. |
|
8 |
Eichenbaum;
Olfactory Perception and Memory |
178 |
|
Within early stages of the visual, auditory, and somatosensory systems it is the relevant and monotonically
coded dimensions, and relations
among them,
that are mapped so systematically. |
|
1 |
Eichenbaum;
Olfactory Perception and Memory |
178 |
|
In the visual
system, early cortical processing
stages detect specific features such as contrast,
color, depth, and movement separately, and the representations of these features are systematically organized. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
178 |
|
At the highest
levels of processing, combinations of simpler features form perceptual
objects. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
178 |
|
The highest-level
processing of the
visual system, combining
simpler features into perceptual objects, occurs in the inferotemporal area with its enormous convergence of inputs
about visual features. At this stage of visual processing, no topography has been identified. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
178 |
|
In the inferotemporal
area there is a
clustering of cells involved in encoding particular stimuli. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
179 |
|
Instead of odor
primitives,
the olfactory system likely uses categorization mechanisms based on distributed olfactory cortical
networks. |
|
1 |
Eichenbaum;
Olfactory Perception and Memory |
179 |
|
Analysis of sensory
processing by cell
assemblies in the relatively simple olfactory cortex
may offer insights into coding at higher levels in other sensory systems. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
179 |
|
Continuous turnover of receptor cells occurs in the olfactory sensorium; receptor cells are gradually renewed. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
179 |
|
Olfactory bulb remains plastic beyond its full development; injury or odor
deprivation can result in reorganization in the bulb well into adulthood. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
179 |
|
Olfactory identification is very poor. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
179 |
|
Odor memories
can be exceedingly
powerful.
A fragrant
perfume can bring forth strong
memories associated
with a long-forgotten
romance. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
179 |
|
Olfactory identification is very poor for humans; they often misidentify
highly familiar odors using only olfactory cues. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
180 |
|
Odor processing does not converge with that of other senses until the final common paths into the entorhinal cortex, amygdala, and prefrontal area. |
|
1 |
Eichenbaum;
Olfactory Perception and Memory |
180 |
|
Vision, audition, and somatosensation merge in temporal and parietal association areas of the neocortex well before the common
paths into the entorhinal
cortex, amygdala, and prefrontal convergence sites. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
180 |
|
Common processing of conventional sensory modalities includes a convergence in the verbal areas of the neocortex. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
180 |
|
Hippocampus
has myriad connections
with many brain areas. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
180 |
|
Olfactory system projects heavily onto and has
especially immediate access to the hippocampal system. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
180 |
|
Hippocampal system in odor-guided learning and memory. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
181 |
|
A pronounced
rhythm dominates the EEG throughout the nonprimate mammalian limbic system during exploratory activity and learning. Theta rhythm range 5-12 Hz. |
|
1 |
Eichenbaum;
Olfactory Perception and Memory |
183 |
|
Hippocampal long-term
potentiation (LTP) is induced preferentially by
electrical stimulation that is based on three separate but related patterns
of afferent activation. |
|
2 |
Eichenbaum;
Olfactory Perception and Memory |
183 |
|
The LTP in CA1
is preferentially induced
by high-frequency
bursts of stimulation (4 pulses
at 100 Hz, repeated at 5 to 10 Hz), and can be induced by a single burst if another burst or single pulse precedes
the that burst by 130
to 200 msec, i.e.latencies that
parallel frequencies of 5-7 Hz. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
183 |
|
Patterned stimulation is most effective in inducing LTP in dentate gyrus when delivered at the peak of dentate theta rhythm |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
183 |
|
Brief episodes of high-frequency
stimulation, when applied in the appropriate temporal relationship to prior
activity and to continuing theta rhythm, can reliably enhance synaptic
efficacy in a brain area critical to the formation of certain types of memory. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
183 |
|
Coherent activity associated with theta bursting appears to pervade the hippocampal
cell population. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
183 |
|
Subsets of hippocampal cells achieve near-synchronous activity relative to particular phases of theta rhythm. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
192 |
|
The binding
problem of early
sensory processing refers to how early-stage, separately-processed stimulus elements are sorted and combined to form perceptually
distinct complex stimuli. |
|
9 |
Eichenbaum;
Olfactory Perception and Memory |
192 |
|
Hippocampal system contains afferents from all sensory modalities. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
192 |
|
Afferents to
the hippocampal system
may be better conceived as functionally rather than perceptually defined inputs. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
198 |
|
Different forms of binding of perceptual elements by components of the hippocampal
system. |
|
6 |
Eichenbaum;
Olfactory Perception and Memory |
198 |
|
In the parahippocampal
region perceptual elements may be bound by a
conceptual fusion or compression into a single configural representation.
This can involve multimodal elements that occur simultaneously or even in
sequence, but they are bound into a single composite encoding. |
|
0 |
Eichenbaum;
Olfactory Perception and Memory |
198 |
|
Hippocampus,
in contrast to the parahippocampal region, prevents the representational
compression when perceptual elements and their relations may need to be
recognized separately at a later time. Representations are bound only by the
memory network in which they reside. |
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0 |
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