Gobierno de la ciudad de Buenos Aires
Hospital Neuropsiquiátrico
"Dr. José Tiburcio Borda"
Laboratorio de Investigaciones Electroneurobiológicas
y
Revista
Electroneurobiología
ISSN: 0328-0446
Minireview
Latest Findings in the
Mechanisms of Cortical ‘Arousal’:
‘Enabling’
Neural Correlates for All Consciousness
by
Bill Faw
Psychology, Brewton-Parker College, Mount Vernon, GA,
U. S.
Contacto
/ correspondence: bfaw [-at-] bpc. edu
Electroneurobiología 2006; 14
(2), pp. 199-210; URL <http://electroneubio.secyt.gov.ar/index2.htm>
Copyright © April
2006 del autor / by the author. Este trabajo es un artículo de acceso público;
su copia exacta y redistribución por cualquier medio están permitidas bajo la
condición de conservar esta noticia y la referencia completa a su publicación
incluyendo la URL (ver arriba). / This is an Open Access article: verbatim
copying and redistribution of this article are permitted in all media for any
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Printing this file does not keep original page numbers. Puede obtener un archivo .PDF
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<http://electroneubio.secyt.gov.ar/index2.html
ABSTRACT: This paper differentiates
traditional "cortical arousal" concepts into separate components for
the functional states termed REM ("rapid-eye-movement sleep"),
Quiet-Waking, and Active-Waking, and traces their involved mechanisms in the
neuronal and biochemical level, i. e.,
skipping from consideration any more fundamental issues such as quantum or
relativistic biophysics. In a short review of the latest findings, these
"classical" mechanisms include (a) basal forebrain
acetylcholine "final path" projections to the cortex for "basic
arousal" in REM and quiet wakefulness; (b) brainstem
neurotransmitter systems allowing incoming stimuli to activate
"arousal", and recruiting additional systems to turn "basic
arousal" into the fuller arousal and capacities of Active Wakefulness
state; (c) thalamic intralaminar-nuclei cortical projections that connect
anterior and posterior cortex for processing sensory stimuli; (d) thalamic
reticular-nucleus which can shut down perceptual transfer between thalamus and
cortex or allow gated transfer; and (e) circadian mechanisms in the basal
forebrain, hypothalamus and pineal gland that direct transitions from waking to
slow-wave sleep to REM and back. (f) More speculatively, it is considered that
circadian clocks alternating control between left and right hemispheres may be
involved in rotations between slow wave sleep (SWS) and REM sleep.
Introduction
Inside
Anglo-American academe, John Searle (2000; 2005) has been chastising the
consciousness researchers for spending so much time on what he calls the "building
blocks" of the neural correlates of consciousness: what it takes for
specific mental 'content' to compete for conscious workspace, as in binocular rivalry.
Searle rather calls on us to focus, instead, on the "unified fields"
question – what makes creatures conscious versus in a deep sleep, coma, or
vegetative state, pursued at the neuronal and biochemical level without
consideration of any more fundamental biophysical issues, e. g. quantum or relativistic. Such mechanisms in this
"classical" level are what Searle calls the neural correlates of consciousness (NCC). Illustrative of
Searle's concerns, Christof Koch, in his otherwise-superb book The Quest for Consciousness (2004),
spends a measly eight pages or so on Searle's "unified fields" (which
Koch calls the “enabling” correlates of the NCC) and the rest of the
book on Searle's "building blocks", and most of that on visual perceptual consciousness. This
article, which for the sake of synopsis leaves outside of its scope the issues
of non-REM-sleep experience (reviewed in Nielsen 2003) and the troubles posed
by the non-mammalian EEG-characterization of sleep-waking states (Crocco 2005),
is an attempt to pull together the latest findings on the unified
fields/enabling neural correlates for all
consciousness and to relate the "enabling" NCC to the "building
blocks" NCCs.
1. Basic Arousal found in REM and Quiet Wakefulness:
Basal
Forebrain Acetylcholine
It
has been traditional to consider both REM and waking states to be
states of consciousness in the phenomenal sense of having conscious
experiences; but to bestow that title to only waking states in the
medical sense of being conscious of ones surroundings. While REM and waking
states share some commonalities in terms of "phenomenal" experiences
– "The dream seemed so real!" –, there are many "access"
differences between REM and waking that affect the quality of the
"phenomenal" experiences. Somewhere between REM and "active
waking" states are the states of "quiet wakefulness"
(Jones, 1998), such as restfulness, absorption, trance, and meditation. The
cortical arousal that is common to REM and to quiet wakefulness can be
called a state of “basic-cortical-arousal” (my term) or a state of “sustained
attention” (Sarter & Bruno, 1998), except that – in the non-lucid REM case
– one is unable to intentionally interact with what is being attended.
Acetylcholine
(ACh) cells in the basal forebrain
(BF), just anterior to the hypothalamus, seem to be the "final
common pathway" (Dringenberg, 1998) for activating the cortex (Jones,
1998), by tonically depolarizing receptors on dendritic spines of rows of
cortical pyramidal (projecting-out) cells in adjacent cortical columns (Dringenberg,
1998). This is likely achieved by preventing the escape of potassium (K+)
ions from these cells (Jones, 1998). This tonic effect on parts of the
cortex presumably leads to the conscious state shared by quiet waking and REM sleep (Sarter & Bruno, 1998). This makes
these cortical cells "trigger happy", so to speak, so that they can
easily be activated by relevant stimuli impinging onto them (whether externally
derived in wakefulness or internally derived in both wakefulness and REM). The
classic term "arousal"
seems to imply that the whole cortex is activated. Yet such homogeneous
activation would be functional mayhem. It seems more like major sections of the
cortex being moved from "at ease" to "get ready, get set . . . ," which makes it readily possible
for them to serve function in normal ways.
Since
ACh projections are active during both REM and quiet wakefulness, perhaps the
degree of REM activation is a
"get ready" state. Then,
hypothalamic histamine projections
to both brainstem and basal forebrain acetylcholine nuclei may be necessary to further
activate the ACh cells to the "get
set" stage of quiet
wakefulness. Norepinephrine
and serotonin activation may be what
allows a further degree of cortical arousal for the “go!” of active
wakefulness (Speigle, 2004).
Clusters
of acetylcholine cells, both in the BF and in the upper brainstem, are very
active during both REM and waking states, but virtually silent during slow wave
sleep (SWS) (Hobson, 2005; Hobson et al.,
2000). During REM activated dream phases, it is only the brainstem acetylcholine
cells (rather than brainstem norepinephrine, dopamine, etc., cells) that
activate the BF acetylcholine cells (Sarter & Bruno, 1998), while during
wakefulness, basal forebrain acetylcholine's wide projection to the cortex is
moderated by a number of other brainstem projections to it. This leads us to
examine pathways that are active during wakefulness, but not
during REM.
2. Brainstem Neurotransmitter Systems' Ventral Projection to Basal Forebrain
a. allow incoming
stimuli to activate "arousal"
Stimulation
of the upper-pons-through-midbrain area wakes a sleeping cat, while destruction
of the area puts a normal cat into permanent coma. From the days of Morruzi and
Magoun (1949) on, this upper brainstem area was seen as crucial for arousal.
Cortical projection from the acetylcholine nuclei in the brainstem
was generally heralded as the
consciousness generator, or rather the generator of a necessary (if, perhaps,
not sufficient) condition for enabling the observer's connection with the surroundings,
while other brainstem area projections from dopamine (DA), norepinephrine (NE),
serotonin (5HT), glutamate (GLU), and endorphins (EN), and the posterior hypothalamus
histamine (H) system were seen as playing supportive roles (Hobson, 2000; Faw,
1997, 2000).
Now
that the basal forebrain acetylcholine clusters are seen as playing the
main role in the state called cortical arousal (Schiff, 2004), the crucial role
of brainstem (and histamine) projections to the acetylcholine cells in
the basal forebrain seem to be the means by which incoming stimuli can activate
arousal, motor control, and salience-detecting systems (Dringenberg, 1998).
This
involvement is seen most clearly in the process of being awakened by an alarm
clock or something else. While you are dreaming, a bright light, a loud noise,
an earthquake, a bitter taste in your mouth or the smell of smoke can wake you
up. What you see, hear, touch, or taste can activate brainstem systems
that are activated during wakefulness, but turned way down during both REM and
SWS, including, NE, DA, GLU and, to a lesser extent, serotonin. These project
to the basal forebrain and surrounding areas to activate from below the
supportive cortical projections that move one to active wakefulness. What you smell
activates the basal forebrain area from above – from olfactory centers
(Jones, 1998). This network of activation from the sensory systems – and a more
or less continual bombardment of sensory input throughout your waking day seem
crucial to keep you in active wakefulness.
b. Brainstem
systems link basic arousal system to other systems
Serotonin
seems to activate the cortex directly and other systems indirectly through ACh
projections (Dringenberg, 1998), to move the tonic cortical condition from
conditions of REM or quiet waking to active waking. A lot of this occurs by way
of an "arousal ventral pathway" (Jones, 1998) through the
hypothalamus to the basal forebrain. The projection of NE from the
pontine locus ceruleus to the BF acetylcholine bed seems to be crucial for
helping subcortical “salience-detecting” centers, such as the DA “reward
circuits”, amygdala, and hippocampus “recruit” the BF Ach projections to the
cortex (Sarter & Bruno, 1998; Dringenberg, 1998). NE also activates primary
sensory areas and the right prefrontal areas – areas whose products
become inaccessible to experience or "shut down" during both SWS and
REM sleep – seemingly to enhance or prolong wakefulness, including increases in
gamma EEG activity (the famous "40 Hz" oscillations) (Jones, 1998)
and maintain vigilance to external events. Downward projection of NE enhances
muscle tone and may set the stage for active wakefulness and coordinating motor
response with vigilance (John et al.,
2004).
The heavy projection of basal forebrain
acetylcholine cells to the hippocampus, made possible by brainstem NE
projections, seems a condition to turn the hippocampus functional as to what
should be evaluated and consolidated into long-term memory. Indeed, very recent
findings indicate that it is the BF acetylcholine projection to the hippocampus
that stimulates stem cell neurogenesis into a condition in which it becomes
possible to consolidate new memories (Mohapel et al., 2005). This is quite consistent with the long-known fact
that BF acetylcholine destruction is linked to the loss of new memory consolidation
in Alzheimer's. BF projections to the cortex are involved in making
those cortical areas more responsive to perceptual and other processing (Jones,
1998) and in helping consolidate into memory the representations
projected there through convergence upon perceptual glutamate pathways
(Rasmusson, 1998).
While
the term "cortical arousal" implies a very diffuse
non-specific ACh projection to the cortex, these ACh projections seem to have
both general tonic and specific phasic characteristics (Szymusiak,
1998). Specific sensory input might further increase acetylcholine activity in
specific cortical regions (Szymusiak, 1998). Thus the term "generalized
arousal" may be too broad (Sarter & Bruno, 1998). And yet, these
projections (and some others to be named) do prepare the cortex for specific
sensory input. A modified definition of
cortical arousal still seems appropriate.
3. The Dorsal Arousal Extension:
a. Thalamic
Intra-laminar Nuclei (ILN)
The
pontine/midbrain reticular formation seems to extend in a "dorsal
path" into the thalamus into a cluster of five midline nuclei stuck in the
white-matter lamina separating lateral from medial thalamus, collectively
called the intra-laminar nuclei (ILN). These thalamic ILN nuclei project
to diverse cortical and subcortical areas to tonically activate the cortex.
This projection to the ILN and from there to the cortex involves glutamate (Parvizi & Damasio,
2001). The ILN projects quite widely to the superficial layers of the cortex,
to prepare cortical cell columns to better receive specific input. This dorsal
pathway through the thalamus has classically been seen as the cortical
arousal system.
More
recently (Schiff, 2004), the ILN projections to the cortex have been found to
be diffuse, but not undifferentiated. The five ILN nuclei project
to slightly different parts of the cortex, with the rostral nuclei projecting
to prefrontal, posterior parietal and primary sensory areas; and the caudal
nuclei projecting to premotor and anterior parietal cortex – and both groups
projecting to corresponding parts of the basal ganglia (Schiff, 2004). They
seem to be activating different parts of long-range cortical pathways
(one might think of Autoban or Interstate
Highways as a simile), especially connecting frontal and parietal lobe,
involved in conscious processing and working memory of contents of sensory experience
sustained by brain states whose neuroactivity is being processed in more local
subdivisions and cul de sacs – and their related basal ganglia loop sections.
These long-distance connections are crucial for normal waking state
functioning. Hobson (2000, 2005) contends that these long-distance connections are almost totally shut
down during both REM and deep sleep, an assertion not yet verified
independently. Anyway, the two main projections to the cortex considered to be
"general arousal" projections (from the ILN Thalamus
and this BF ACh projection) are now seen as having considerable specificity
(Jones, 1998). Recently it has been shown that the ILN neurons are modulated by
posterior-hypothalamic hypocretin (Hcrt) neurons (Schiff, 2004).
b. Thalamic
Reticular Nucleus (RNT)
As
part of a one-two arousal punch for this dorsal extension, the brainstem acetylcholine projection to another
thalamic fixture is crucial for normal waking
arousal. Surrounding much of each of the two thalami is a net-like covering
called the reticular (net-like) nucleus of the thalamus (RNT), through which to-and-fro
projections between the thalamus and cortex pass (imagine wires sticking through
a window screen). These passing fibers send collaterals to the
"screen" RNT to laterally inhibit transmission through other fibers sticking through
neighboring parts of the screen. This seems to be a major mechanism employed in
selective attention (LaBerge, 2000). During waking states, the RNT thalamus
seems in "transport mode" (Detari, 1998) and the doors of perception are open, so that one can interact
with the outside world. In transport mode, the reticular nucleus of the
thalamus serves the basic "gating" function of determining
which thalamic-cortical "relay" pathways are in play and which are
not.
During
sleep, the thalamus is in the "oscillatory mode" (Detari,
1998). The inhibitory reticular nucleus is massively turned up during sleep,
inhibiting cortical pyramidal cells, and thus serving as what appears as a
pacemaker for the thalamic spindle oscillations of deep sleep. Both
brainstem and basal forebrain (Dringenberg, 1998) acetylcholine and NE,
serotonin and H projections (Detari, 1998) block the generation of these
spindles and thus initiate the wakeful state (Steriade & McCarley, 1990;
Steriade, 2006; Parvizi & Damasio, 2001), placing the thalamus into
"transfer mode".
When
the ILN projects to various parts of working memory cortex/basal ganglia loops
and when the reticular nucleus of the thalamus allows interaction between
sensory systems and cortical areas, the BF Ach projections to those same
cortical areas are involved in enabling the same basic mechanisms of memory
consolidation found in the hippocampus. The lack of this two-way punch during
SWS and REM is probably involved in determining why we have such poor memory of
SWS mentation and REM dreams, unless we awake from them.
4. Circadian involvement: SCN, VLPO and Pineal
We
have already noted that sudden or intense sensory stimulation from any modality
can activate the waking mechanisms through brainstem and olfactory systems –
adding activation beyond the basic ACh activation. But, most of us do not
always continue sleeping until something awakens us. We have natural circadian
systems that control shifts from waking to SWS to REM and so on. These, in
turn, are affected by changes in light duration, physical exercise, hormonal
changes, stress conditions, and recent mental activity.
Several
inter-connected hypothalamic neuron clusters and the pineal gland are involved
in shifts of circadian rhythm, which then control the brainstem arousal and
motor areas involving the various neurotransmitters. In anterior hypothalamus
are the suprachiasmatic nucleus (SCN)
and ventro-lateral preoptic area (VLPO),
the latter being adjacent to the basal forebrain. Rats with damage to the SCN
sleep erratically, showing no night-day rhythm.
The
SCN receives direct retinal input
through the retino-hypothalamic tract and indirect visual input from the LGN
thalamus, to adjust natural sleep-waking cycles to daily and seasonal shifts in
light. The SCN projects to the pineal
gland to convert serotonin to melatonin, whose available concentration is
somehow related in diurnal species to drowsiness in response to waning light.
The SCN projects to other hypothalamic nuclei to modulate body temperature and
the production of hormones consistent with circadian needs. The VLPO area has "sleep cells"
that project the major inhibitory neurotransmitter GABA to turn down a
number of arousal and motor centers (Jones, 1998; Morairty et al., 1998). It is increasingly being appreciated that adenosine
buildup in anterior hypothalamus and basal forebrain (Szymusiak, 1998) may be a
major sleep factor (Morairty et al.,
1998). Adenosine inhibits the neighboring ACh neurons in the basal forebrain
(McCarley, 1998). All cellular activity involves adenosine in energy transfer
and in second-messenger reactions for hormones and neurotransmitters. The
longer one is awake, the more this adenosine builds up. Its buildup specifically
in the basal forebrain has recently been seen to be directly proportional
to sleepiness (McCarley, 1998; Porkka-Heiskanen, 1999). Consistent with these
findings is the fact that the main effect of caffeine is on the adenosine
second-messenger system, inhibiting the breakdown into adenosine. Thus, GABA
and adenosine may be specific slow-wave sleep factors, moving us from
wakefulness to SWS.
In
posterior hypothalamus are the newly examined hypocretin (orexin) and histamine systems. The hypocretin system seems to be a
“toggle” switch (Schiff, 2004) by which circadian mechanisms can directly
activate the brainstem and basal forebrain arousal and motor systems – in
addition to any sensory stimuli activation. The hypocretin (Hcrt) area projects densely to the SCN, helping
to maintain the full circadian cycle. Lower Hcrt levels leads to lower
amplitude of circadian cycles and thus to narcolepsy (John et al., 2004). In terms of waking
arousal mechanisms, Hcrt projects to both brainstem and basal
forebrain acetylcholine centers, likely leading to cortical arousal,
during both waking and REM (Kiyashchenko et
al., 2002). Hcrt also projects to the ILN neurons in the thalamus to modulate
them (Schiff, 2004). The Hcrt-2 neurons project to excite neighboring
posterior-hypothalamic histamine (H)
neurons. Histamine, in turn, projects to the thalamus, to brainstem and basal
forebrain arousal centers and to much of the cerebral cortex (Gazzaniga, 2002).
Histamine neurons are found to be basically quiet during both REM and SWS
sleep, highest during active waking and fairly high during quiet waking. This
implicates H for waking but not REM cortical arousal. And the arousal effect of
histamine is heavily dependent on Hcrt. Very recent studies of Hcrt, histamine
and norepinephrine (NE) show a very interesting interaction. In narcolepsy (when one is asleep plus paralyzed),
histamine levels are quite low. But, during cataplexy (which combines the greatly reduced muscle tone – paralysis
– found in REM and narcolepsy, with the awareness of events around one, found
in wakefulness), H levels are at the same level as in quiet wakefulness
– which catalepsy seems to be – but NE levels are very low and 5HT levels
are pretty low. This suggests that histamine may be a crucial factor in waking
arousal – and then NE, 5HT and DA – add to waking arousal the
“active” component of “active waking” (John et al., 2004). Stimulating H centers leads to arousal and, as we all
know, antihistamine leads to drowsiness.
5. Circadian clocks alternating control between left
and right hemispheres may be involved in rotation between SWS and REM sleep
One of the least developed
questions in terms of circadian control of conscious and unconscious states is
the alternation between slow wave sleep and REM through the sleep cycle. REM
phases are initiated by so-called PGO (pontine-geniculate-occipital)
spikes from acetylcholine cells in the pons. The tonic inhibition of the
gamma-motor neuron system, which virtually paralyzes most somatic muscles
during REM is triggered by acetylcholine cells in the medulla. But what
circadian mechanisms set them off?
There is considerable evidence for a
90-minute or so alternation between left and right hemisphere dominance
throughout waking and sleeping states. A very recent field of study has been proposed
to demonstrate one extremely simple and low-tech way of detecting which
hemisphere is dominant at any one time, which is to restrict the breathing
through one nostril at a time and determine which one is actually breathing –
or breathing most robustly – at that time. The opposite hemisphere is
presumably dominant at that time.
It is now clear that there is
"mentation" during both REM and SWS parts of the cycle, but some such
as Hobson (2000) contend that REM mentation tends to be much more
perception-like, while SWS mentation tends to be much more verbal-thought-like.
It might be that, for most people, the SWS mentation is linked to parts of the hemispheric
cycles when the left hemisphere is dominant and REM mentation linked to the
right. Solving this switch from SWS to REM and back will allow us to pull
together a coherent story of the
neural correlates of conscious states.
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SOCIOLOGÍA DE LAS NEUROCIENCIAS
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Cálculo
de potenciales dentro de las células
Calcule
intensidades eléctricas y magnéticas en cada compartimiento neuronal: The nervous principle: active versus passive electric
processes in neurons (Explains how to calculate electric and magnetic
field strengths inside different neuronal compartments) (LONG FILE IN ENGLISH with
Bulgarian, Russian and Spanish abstracts/TOCs)
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Evaluación de
potenciales fuera de las células
Signal analysis to exploit the information of steady-state recordings: Do’s and don’ts in Fourier analysis of steady-state potentials
(Assumptions in the discrete Fourier transform (DFT) not necessarily fulfilled in real-world applications) (English)
NOCIONES GENERALES
Conceptos:
Noticia general -- ¿Qué es electroneurobiología? -- La
atmósfera intelectual (all in Spanish) -- Main Technical Ideas / Conceptos
técnicos principales (English and
Spanish) -- El descubrimiento de la Doppelrinde (German and Spanish)
Comentando una "ilusión óptica" / Commenting an "optical illusion":
A visual yet non-optical subjective intonation:
una entonación subjetiva visual pero no óptica
(English and
Spanish)
UNA EXPLICACIÓN ESENCIAL:
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Historia de las
experimentaciones:
Table of Contents (partial) of "Sensing: a new
fundamental action of nature" (English) -- Índices
Reseña historiográfica: Historia y recepción del redescubrimiento (1985) de la proeza biomédica de Alberto Alberti (1883), luego Primario del Hospital Italiano de Buenos Aires, relatada por sus autores (Spanish)
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1976: La introducción de los conceptos de eclosión existencial y de conocimiento como reacción causal.
A treinta años de la patente británica UK 1582301: inserción del psiquismo en el arco sensoriomotor (Spanish)
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Recepción
de los aportes de Chr. Jakob en la neurobiología germana
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Adolf von Strümpell (1853-1925) fue factor definitorio en la ruptura de Josef Breuer con Sigmund Freud. Los vínculos de amistad que unían a Christofredo Jakob (1866-1956) con su ilustre maestro y buen amigo nunca se resintieron por la separación que les impusiera la distancia y el tiempo; Jakob, asimismo, respetó el secreto de von Strümpell acerca de la enfermedad que padecía Lenin. -- Oddo y ot.: El Maestro de la medicina platense Christofredo Jakob, discípulo y amigo de Adolf von Strümpell
(Spanish: ARCHIVO DE DESCARGA LENTA POR LLEVAR MUCHAS ILUSTRACIONES)
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Recepción
de los aportes de Chr. Jakob en la neurobiología y la sociedad argentina
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Piva y Virasoro - Christofredo
Jakob, neurobiólogo: científico en diálogo filosófico (Spanish)
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Panorama
evolutivo:
¡Nuevo! Diego Luis Outes - A medio siglo de la muerte de Christofredo Jakob, 1956-2006: Fuentes de la concepción biológica de la Doble Corteza (Spanish)
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FILOSOFÍA DE LA CIENCIA - CONCEPTO DE TIEMPO EN
NEUROBIOFÍSICA
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RESUMEN
DIVULGATORIO Y PARA ESTUDIANTES EN CASTELLANO
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“ANTAGONISMO ENTRE
CIENCIAS DURAS Y HUMANIDADES BLANDAS”
MALFORMACIONES Y PAPEL DEL ÓRGANO CEREBRAL
Christofredo Jakob: “Los
Monstruos Anencéfalos” (Spanish)
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BIOÉTICA
Éthique de la Bio-Éthique (français) ¡Nuevo!
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EL PRESUNTO
DUALISMO CUERPO - ALMA
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PSICOANÁLISIS Y
FACILITACIóN PSICOSOMÁTICA DE
LA ENF. DE ALZHEIMER
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PERICIAS
JUDICIALES Y CASUÍSTICA
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NUESTRA GENTE
Arturo Carrillo, con la colaboración de Augusto Raúl Carrillo : segmentos de su libro "Ramón Carrillo. El hombre... El médico... El sanitarista"
(Spanish)
Libro declarado de Interés Cultural por la Legislatura de la Ciudad Autónoma de Buenos Aires
seguidos de una
Noticia biográfica del Dr. Arturo Carrillo (Spanish)
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Breve reseña biográfica: Ramón Carrillo, el Gran
Sanitarista Argentino, por Marcos Ordóñez (Spanish)
Breve semblanza personal: Recuerdos de Ramón Carrillo, con diez fotografías inéditas de Carrillo, la madre del presidente Perón y la hija de éste, la campaña sanitaria de la Patagonia y la formación de médicos becarios latinoamericanos, por Arturo Pimentel (Spanish)
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Ayer, hoy y mañana: el enfermo mental con organicidad ante la devastación del lazo social. Temas de psicología institucional, desmanicomialización y cambio social. Introducción al trabajo "Memorias de un Psiquíatra", por Santiago Héctor Valdés, cuyo texto completo se halla disponible abajo.
(Spanish)
Santiago Héctor Valdés, "Memorias de un Psiquíatra". Anécdotas de la vida de hospicio y avatares del ejercicio de la psiquiatría (Spanish).
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ESCATOLOGÍA – POSTMORTALIDAD – EL PUESTO DE LA HUMANIDAD EN LO REAL
(ESCHATOLOGIE – LEBEN NACH DEM TOD – DIE STELLUNG
DES MENSCHEN IM KOSMOS)
[Nota para distraídos: "Sé verlas al revés" es también un palindrome]
SUMMARY: It is reported a palindromic relationship between the astrophysical-biological evolution and the experiencing beings in it. The issue is related with ascertaining if nature is an instrument (as merely a means), instead of having any intrinsic value (an end in itself); and, likewise, if conscious beings are merely a means (one to entropize nature faster) or either possess any intrinsic value. Two possibilities are deemed not indifferent in this regard: either reading the whole set of empirically-found realities or facts makes sense in both directions (palindromic reading of nature), or, rather, that sense can only be ascribed to such a set by reading it in some single direction. A single direction means reading nature in a classic, materialist or idealist sense; both directions' sense means a mirror or reciprocal functionalization, in which each of both realities (mind-possessing living creatures, and astrophysical-biospheric evolution) uses for its own ends the reality that uses it as a means. At stake, therefore, is establishing if axiological readings ascribing a sense to what is found going on in the universe can be obtained in both directions, or not. On this alternative, it is claimed, pivots the possibility of ascertaining, e.g., whether conscious beings are worthier than non-conscious nature, or not - a topic assumed consequential for philosophy, ecology, ecofeminism and biocentric environmental movements, and ethics.
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PROCEDIMIENTO
Los "Cortes de Jakob": Christofredo Jakob: La técnica moderna en la autopsia del cerebro. Exposición clara y didáctica de la técnica, por su autor, con ilustraciones y la explicación de sus fundamentos (Spanish).
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Estos artículos cubren sólo algunos de los temas que se explorarán en este documentado sitio de Red, por ahora en construcción. Abrirá completo en unos meses.
[Prof. Mariela Szirko
cuida estas páginas/cares of these pages.]