Barely a
hundred and thirty years have passed since Wundt’s rejection of the innere Wahrnehmung -the traditional
philosophical internal perception as a psychological method- in favor of the experimentelle Selbstbeobachtung[1] -or experimental self-observation. However, during
this time, we have witnessed not only the birth of genetic science, which has
completely changed the vision we had of physiology, but we have also
experienced a general scientific revolution -in the sense of Kuhn-, in
which we have altered our general understanding of life sciences. The theory of
the animal organism as a dynamic system of proteins[2]
that emerges from a specific physico-chemical environment which is in a continuous interaction with it,
has allowed us to elaborate theoretical models in which human life is entirely
integrated into the general biological process of the planet, without the need to
appeal to supernatural hypotheses. This new myth has introduced more precision and coherence to
the rest of scientific knowledge, and in the
neurological plane, it has allowed the first integrated model of brain activity within the joint system of organism
and environment, a model which can be projected over the old terms of
introspective psychology.
I do
not mean to say that a description of man from the processes of proteins and macromolecules can suffice to characterize us: it could never
be inferred from the mere biochemical interactions, for instance, an orchestral
piece, or the idea of democracy, nor in
general, any human symbolical representation. In fact, proteins and
macromolecules are late guests, recent arrivals, like so many other concepts of
contemporary science, to the human festival of knowledge. Scientific concepts
make sense within knowledge structures that are analogous to those of
traditional myths, and
they do so in the measure that the theories to which they belong may be integrated into
some structure, whose economic and primitive determinations may be
operational within a given historical community that lives according to the
knowledge explicitly stated by those theories. The idea of scientific
reductionism is a metaphysical remnant of Leibniz’s Characteristica Universalis,
a concept which is used nowadays with connotations of priestly power struggles
in academic scholastics, but it lacks any pragmatic meaning, for it does not
make any sense to add stars with democratic constitutions, nor ants with
symphonies. Nevertheless, meta-theory makes sense as a tool for analysis and
manipulation of symbolic systems, as well as for the construction of complex
frameworks of conceptualization, even though it has to be capable of making
metaphorical images (not necessarily isomorphic) in the intuitive
terms in which the representations of the social determinations are elaborated,
in order to avoid the so much repeated hypostases.
Intuitions
in relation to general biological processes are relatively common and simple, we
experience them continuously in the form of health,
illness, pleasure, pain, birth,
death, hunger,
sleepiness, etc.
Obviously, these concepts, and the like, are endomorphic from the point of view of the life sciences,
they are reducible to other representations, but
have allowed us, during the almost two hundred thousand years life span of our
species, a basic self-knowledge. From them, we have understood the bond that we
share with other living beings, a knowledge from which we derived a kind of Lebenswelt which,
for instance, makes closer the basic intuitions of evolution theory than those
of quantum physics, for
they correspond to a symbolization that is more distant from our everyday life
experience. The epistemological problems have arisen once we have abandoned
the intuitive representations of our theories and ideologies, when we have negated basic
life intuitions in favor of symbolic constructions that do not correspond with
experience, saying that to die is to be
born, to be born is to die, dreams are more real than reality, reality is a
dream, and other value reversals to which we have grown accustomed to
through the fantasy of metaphysical myths. The
basic intuitions of the Lebenswelt have
been translated to such myths, and the
difficulty that we find today with the life sciences, no less than in the 19th
Century, is that of successfully disassembling mythic systems of various kinds which burden the
thought with prejudice, whether supernatural -gods or divine plans that go beyond life-, or natural -like
those which lead us to unconscious metaphysical affirmations such as complexity is (or is not)
the goal of evolution,[3] hypostatizing an epistemological concept (complexity) beyond its valuable
capabilities for determining experience.
The
mythologization undertaken by modern science has onto-theologized a wide
catalogue of its tools and objects of study, from the elemental particles to
the human sciences and the arts, through
molecules, cells, and
live organisms with intelligent behavior. Such
objects are part of narrative of universal law, the
believe in a final objective order in the universe from which humans partake in their tiny little
scale: traditional gods have disappear but not the theologization of
the world. Each one of these systems of objects keeps a generative relation
with respect to a simpler set, which determines its conditions of possibility,
as it occurs, for instance, in the relationship that conceptual systems of
anthropology have with the physiological organisms that have cortical brains, and of such organisms with respect to
cells, and of
these with respect to molecules, then atoms, particles, strings, etc. This
chain of conditionings is implicit in the theory of evolution, although it goes
beyond it. From the Kantian point of view, we would say that it is a
requirement of our reason: we need
chains of links between phenomena, in fact, such chains are inseparable from
what we call the world experience, though their hypostasis beyond epistemological grounds and usefulness is unnecessary. The domains of these conceptual
objects are contiguously linked, and are conditioned in similar manner. If, for
instance, we call domain one to the one integrated by molecular objects and
relations and two to that of cellular objects and relations, the relations R1
of domain one between the objects O1, condition the
composition of objects and relations in domain two, however, besides a set of relations
R2, which remain conditioned by R1, there is another set
R’2, to which we call the set of emergent relations that are not directly inferable
neither from the relations nor from the objects of domain one. Thus, for
instance, we cannot infer a process of meiosis from the properties of proteins.[4]
Each domain D2, possesses therefore a degree of independence with
respect to the conditionings of D1, and at the same time, is capable
of conditioning it as long as it does not contradict those of R1, as
it is the case of the molecules which conform a cell, whose movement is conditioned to the cellular processes as
long as these do not contradict the molecular ones. At another level, the
psychological and anthropological domains, for example, maintain analogous
relations: the social organization of primates depends on a neurophysiological collection of factors which do not condition
the construction of a democratic and multi-party political system, even though,
they do condition the existence of some form of social organization.
The
understanding of emotions from an evolutionary perspective depends on the development of a
neurological theoretical model and its subsequent philosophical interpretation.
I will adopt the theory neural groups selection as an evolutionary model of the brain. It was
initiated by Gerald Edelman and continued by Giulio Tononi,[5]
and it is also called Neural Darwinism, a model to which I will incorporate the some theses of
affective and social neuroscience, as they
have been experimentally developed by Jaak Panksepp and others. Thus, I will use a mixed model
that allows to go through the neural processes from their most basic
formulations in simple organisms to the emotions of the great mammals and the human being. Schematically,[6]
we can say that the theory of Neural
Darwinism proposes a dynamic system formed by two sets of structures, one
topo-biological whose elements are neurons, and the
other biophysical, the natural vital environment, which
transforms the first structure by means of processes of reinforcement or dissolution of the relations of such a structure,
something that will occur in accordance to the greater or lesser activity of
the topo-biological relations with respect to the biophysical. The
theory proposes a detailed mechanism of the formation of neural groups in the
brain which establish diverse morphisms in relation to the world, categorizing it in a
double and interactive process of selection over variation. The process of
selection occurs both in the embryo and the postnatal developmental phase, and
in this process, the adjacent neurons connect with each other in collectives of
variable sizes forming neural groups.[7]
On the other hand, the process of variation is produced due to the alterations
of the strength of the synaptic connections during the animal’s activity, being reinforced
the ones that have shown a higher adaptive behavior in relation to the environment and being
weakened the ones that did not show this adaptation.[8]
The theory offers a model of brain development in terms of the recursive biochemical processes that are subjected to reinforcements
based on statistical frequencies. According to the model, neuroanatomy is the result of processes of neuronal
grouping in which the brain systems that we know today are determined. Such
systems have been evolutionarily formed in numerous sensory-motor processes of
the organism, to which Edelman has called global
mappings. A global mapping creates a dynamic and open cycle which ensures
the continuous adjustment of behavior and of the homeostatic state of the organism in order to face the changing vital situation. It does
not function like a computer program, obviously: the changes occur within a
system that makes a selection in a continuous manner after the changing inputs.[9]
It is of a probabilistic nature, for the
input of the system cannot be always the same, except in situations of
scientific experiment, but it does produce a reinforcement of the states that
have already occurred. Global mappings, as
results of the evolution of aggregates of simpler different mappings, have a
triple phylogenetic, ontogenetic and epigenetic dimension, and it is at this last level where
the processes of perceptual categorization are produced, structures of neural
groups and relations amongst them that have produced successful homeostatic vital behaviors. Categorizations do not only
occur in processes of perceptual mappings, with exomorphic relations, for they can also be the result of
endomorphic mappings in which the objects are other
mappings, or the very perceptual categories, i.e. a kind of mapping of second
order that Edelman calls conceptual.[10]
According to this, we could define the notion of concept in neurological evolutionary terms, generalizing the notions of endomorphic and exomorphic relationship that we have introduced. Thus, we
can say that a concept is an endomorphic relation between neural groups of the brain
that take as arguments endomorphic or exomorphic categorization processes. Analogously, perception would be an exomorphic relationship of a neural population with the
biophysical environment. There can be therefore, processes of conceptual
categorization that take as argument different previous perceptual
categorizations, and in
this sense they would have an exomorphic referent, whereas other conceptual
categorizations can take other concepts as argument, in
processes of increasing endomorphical abstraction.
The
conceptual categorization as well as the perceptual follow evolutionary criteria for the regulation of the homeostasis of the organism: what is relevant for survival is categorized. In this scheme, memory corresponds to a re-categorization -a successful selection-, to a process, and
not to a symbolic representation. We have to differentiate between the
formation of memory in a neural population, and the linguistic symbolic character of explicit memory: there
is no pre-codified message in the signal, neither structures capable of a
precise code storage, nor a judge in nature that provides decisions on alternative
patterns, or a homunculus in the brain that may read the message.[11]
The distinction is relevant, for if we confuse a neurological system with a
communicative system we will end up assigning emergent properties from the latter to the former,
however, we can actually observe processes that we could call proto-symbolizations at the most basic
levels of perceptive biological processes. Obviously, if by sign we understand a substitutive representation of another, we will not find sings at
a biochemical level, but referential molecular processes. However, the recursive character of the neural mappings of conceptual
categorization, implies that the perceptual mappings will be taken as arguments of the conceptual
ones, and a degree of effectiveness of the conceptual category over the
perceptual one analogous to that of a symbolic operation. The conceptual
category has to be capable of binding a perceptual category to another that in
principle does not seem related even in the absence of the stimulus that produced such categorizations,[12]
in the same way that a sign establishes a relationship with that which is
symbolized in the absence of the specific stimuli that bind the subject with the symbolic
contents.
In
the model of Neural Darwinism, consciousness emerges as another process in the evolutionary configurations of the functional architecture. The
conceptual categorizations, valuated
after the protocols of the limbic system, that
is, the conceptual memories that had evolutionary success in relation to the physiological functions performed by the limbic system, are
put into contact with current reentrant mappings, with
the present perceptual categorizations, by
which the coherence of the present scenario (spatio-temporal locations and
their objects and relations) is contrasted with that of past scenarios. To this
contrast of memorized valuations of conceptual and perceptual categorizations with the perceptual categorization of the
present, in multiple reentrant processes, Edelman calls it primary
consciousness.[13]
The neural systems linked to the concept of primary consciousness
emerged evolutionarily as a result of their ability to integrate and coordinate
a high number of sensory inputs and motor outputs that
occurred simultaneously. A sufficient condition, although not necessary, for
this type of consciousness is the cortical activity, although it has to be accompanied by
biochemically stable memory systems of valuation, so we could say that it
is a form of consciousness which has around 300 to 250 million years of age.[14]
More evolved forms of consciousness are parallel to later morphological
developments of the mammalian brain linked to the ability for symbolization and to language.
The
model of Neural Darwinism provides a morphosyntactic description of the brain,
expressed in physiological terms, from the interaction dynamics between
the live organism and the environment,
something which is consistent with the standardized models that neuroscience offers for the functioning of the nervous
system in concurrence to morphology and development.[15]
The postulation of the somatic selection, the valuation based on evolutionary criteria, connects topobiology and brain functionality, unifying the
morphogenic physiological action with the psychological
action of the organism as an evolutionary unit in relation to the environment.
Neural
Darwinism was criticized by Francis Crick for its no-postulation of a mechanism for
heritability in neural populations,[16]
and also by Horace Barlow,[17]
on the basis of the obscurity of Edelman’s
definitions and the proposed dynamics for neural groups.
However, later experimental studies made by Wolf Singer on the one hand, and Reinhard Eckhorn on the other, have corroborated the existence of neural groups cooperatively linked which
are fired at the same time and respond as units. They also have provided
empirical evidence about the reentrant correlation of
selected events in different maps.[18]
On the other hand, the theses of Neural Darwinism have been corroborated in the
recent investigations of Chrisanta Fernando, Richard
Goldstein and Eörs Szathamáry, who have demonstrated the
existence of evolutionary units in the brain, copy
processes of neural activity that are implemented in evolutionary algorithms, operations of replication which
are conditioned by Hebbian learning (the association of neurons that are simultaneously active) in which the
local optimizations of previous neural states condition future replication.[19]
The
model of neural Darwinism can be interpreted without assuming the ontological
reality of the external biophysical structure as independent from the neural
structure, and that is precisely my interpretation. Cognition is neither a mapping nor the representation of
an external world in a system:[20]
the very same idea of an external world, of something alien, is already a
cognitive representation. Neither is a combinatory gain
produced by the differentiation that a system effectuates when closing itself
in relation to the environment,[21]
for the idea of combinatory gain in relation to a vital system would entail the independence of the syntactic component of the system (combinatory) in
relation to the processes of determination (semantic). The
vital system, dissipative and irreversible, is morphized in repetitive cyclical actions, taking shape as memory. Such a
morphization creates referential chains of processes, which depending on their
position in the memory sequence will have a referential primitive character -or exomorphic-, or a
referential character relative to other processes –or endomorphic.
If we
now extend Edelman’s model
using the evolutionist models of Panksepp’s affective neuroscience and
the so called cognitive neuroscience of
emotion of Antonio Damasio, Richard Lane, Joseph
Ledoux and others, we can construct a theory of emotions that links the physiological processes with the human symbolic processes.
As theses
shared by the different neuro-affective models we could mention:
1. Human emotions show a continuum with mammalian emotions. A similar thesis to this one was maintained
for the first time in philosophy by Aristotle, who
from his observations of the natural world concluded that life proceeds in a
gradual manner in all its activities, which led to advocate an emotional continuity, and even intellective, between
humans and animals, a
thesis that did not supposed any epistemological problem in his system.[22]
In fact, the theses about life as intelligence, found
at the end of the Metaphysics,[23] are based on such a continuity.
2. Emotions are the result of the functioning of
neural systems of behavioral control, and were developed as
an adaptive evolutionary response of those neural systems.[24]
Current neuroscience postulates that the developments of the
evolved neural systems, like the limbic system,
empowered organisms with a wider repertoire of behaviors as well as with the
ability to anticipate dangerous encounters.[25]
The emotional neural systems are related to the homeostasis of the organism,[26]
to the processes of metabolic[27]
self-regulation which is necessary for the maintenance of the functional
parametric environments that allow the maximum energetic efficiency. It is
precisely by being linked to homeostasis that the emotional systems perform an effective control over the
internal and external actions of the organism, linking one with the other. The
existence of such systems, and their location in the
brain at a subcortical and precognitive level, has experimental evidence: the
stimulation of a specific area of the brain produces an emotion and not
another, and certain areas of the brain do not produce any emotions whatsoever when they are stimulated
(electrical or biochemically), in the same way as a local tumor pathology can generate chronic stimulations of a specific
emotion without the need of any external stimulus.[28]
3. These emotional brain systems would not only act in survival situations, but they would be responsible of
the general behavior of the organisms, providing them with systems
of values that would reinforce some actions over others.[29]
Emotions empower mammals with a behavioral coherence which is
determined from species to species according to the actions that produced the
evolutionary success of each one. Thus, for example, an
emotion such as fear, is not
elicited by the same external stimulus in all organisms, for not all of them face the
same dangers. In an experiment performed with rodents born in the laboratory,
without any previous contact with predators of any kind, the exposition to cat
smell completely interrupted their games (during five days and without any feline
presence except the odor), whereas dog smell did not interfere at all with
their ludic tendency.[30]
4. Emotional systems are hierarchically organized, and
interact with the most evolved cognitive structures, as well as with the inferior
levels of the organism, by means of specific physiological an motor outputs.[31]
A distinction is made between implicit or unconscious emotion and explicit emotion, although the
boundary is not clearly defined. The distinction is relevant for emotions as well as for other brain processes which occur in an implicit and an
explicit manner, like perception, memory, motor
control, or language itself.[32]
We can outline parallelisms between the different components of the functional
architecture of the brain and the ever more complex
emotional forms, something that allows us to speak about
two emotional hierarchical orders, one which follows the
evolutionary order of appearance, from bottom-up, and the other
which follows the inverse order. Thus, to the brain stem corresponds the basic
emotional visceral activations, to the diencephalon, the
tendencies towards action, to the limbic system,
discrete emotion, to the para-limbic system, the combinations
of emotions, and to the frontal cortex, the
combinations of combinations of emotions.[33]
[1] Ibid. p.p.18 and s.q.
[2] According to the current estate of the research, the
human body has around 104 types of different proteins and a total of
1022 proteins. Proteins are precise molecular machines that can
detect, unite, transport and modify other molecules. See Müller-Esterl, Werner. Bioquímica. Ed. Reverte. Barcelona. 2008. p.p.77-103.
[3] Issues discussed in The Oxford Book of Rationality. Alfred R. Mele and Piers Rawling,
Editors. Oxford University Press. New York. 2004. p.434.
[4] Meiosis is a type of cellular division that occurs
during the production of gametes (masculine and feminine reproductive cells), in which two successive nuclear divisions take
place from which cells will emerge
that are genetically different from the cell that produced them.
[5] The first book of Edelman in which the
theory is exposed is from 1978, and was developed later in the next decade in The Mindful Brain. Neural Darwinism, The Theory of
Neuronal Group Selection.
[6] For more details see Appendix of this book.
[7] Cf. Edelman. Neural
Darwinism: Selection and
Reentrant Signaling in Higher Brain Function. Neuron, Vol. 10. p.115. February. Cell Press. 1993.
[8] Ibid.
[9] In fact, the neurological functional architecture does not
resemble that of any machine that we may
presently have. The neurological architecture is different from the
computational in three fundamental aspects. First of all, the fuzzy definition
of the architecture: the neural groups, as well as the anatomic connections in general, are
not present simultaneously at a given moment, and the territories of the neural
populations are fuzzy as well, what is more, the neural populations die or are
transformed, whereas we have not built any computer architecture
similar to that. Secondly, the neural connections are not only electrical, but
biochemical: cells have a
self-regulatory structure determined by genes, whose order of complexity is different to
the mere physical domain. Lastly,
we do not have computational architectures that can handle connections to the
fifteenth power.
[11] G. M. Edelman and G. Tononi, Consciousness:
How Matter Becomes Imagination. Penguin Books. London. 2001. p.94.
[12] Cf. Edelman. Bright Air,
Brilliant Fire: On the Matter of the Mind. Basic Books. New York. 1992.
p.p.108-109.
[13] In terms of physiological architecture, the brain stem, the
hypothalamus, and the autonomous nervous centers receive information about the
internal state of the organism and relate it with the one that in the
hippocampus, the amygdala, and the septum is received
from the sensory cortex, and this synthesis is related with the valuations of previous
states of the system which have been stored in the frontal, parietal and
temporal cortex. See Edelman, Bright Air,
Brilliant Fire. Ed. Cit. p.p.117-123.
[14] By biochemically stable memory systems of
valuation, Edelman understands
those which may not restrictively depend of environmental conditions, as in the
case of reptile’s temperature, that would allow the categorization only under
certain conditions. The temporal interval, is the one given by two different
proposals: Edelman, 300 million years (Bright Air, Brilliant Fire. Ed. Cit. p.123.), whereas for Panksepp, who identifies primary consciousness with affective
consciousness, lowers the number to the boundary
of the 250 million years. (Panksepp. Affective
Neuroscience. Ed. Cit. p.35.).
[15] See for example a university textbook highly spread
like that of the Gazzaniga, Michael S., Ivrey, Richard B., Mangun George R.; Cognitive Neuroscience. The Biology of the
Mind. Norton. New York. 2009.
[16] Francis Crick, Neural
Edelmanism, Trends in Neuroscience. Volume 12. Issue 7. Elsevier. 1989.
p.p.240-248.
[17] Horace Barlow, Neuroscience:
a new era? Nature. Volume 331. 18th February. Nature Publishing
Group. 1988. p.571. Web.
[19] The hypothesis of the neural replicator, as it is known, does not postulate that the
evolutionary brain units are
conscious thoughts as such, but that their dynamic follows the processes
proposed in the neural model. See Fernando, Chrisantha; Goldstein, Richard; and Szathmáry, Eörs. The Neural Replicator Hypothesis. Neural Computation. November,
2010, Vol.22, No.11, p.p.2809-2857. Web.
[20] Cf. Niklas Luhman, The cognitive program of constructivism and a reality that
remains unknown. In Delanty, Gerard, and
Strydom, Piet. Philosophies of Social
Science: The Classic and Contemporary Readings. Open University Press.
Maidenhead. Philadelphia. 2010. P.441.
[21] As Luhman proposes in Ibid.
[22] See Aristotle, History of
Animals. 588.1-489.1.a.3. From our evolutionistic perspective is easy to
see an evolutionary outline in this
Book VIII, but in any case, it is interesting the contrast between the
Aristotelian thesis 24 centuries earlier, with the ones that barely some
decades ago (even today) blocked the development of affective neuroscience, sustaining that the study of the emotions in animals was in the best
of cases (if it had anything positive at all), irrelevant for the understanding
of human emotions.
[23] Book Lambda. 1072 b.14.
[24] Jaak Panksepp. Affective
Neuroscience. Ed. Cit. p.25. It is also Antonio Damasio’s thesis. Emotion in the perspective of an integrated
nervous system. Brain Research Review. 26 (1998) p.p.83-86. Web. This
was already anticipated as a thesis from etiological observations by Charles Darwin in The Expression of Emotions in Man and Animals of 1872. And later in
the decade of the sixties, with the works of Konrad Lorenz, Nico Tinbergen and
Karl von Frisch.
[25] Cf. J.T. Cacioppo and G.G. Bernston. Social Neuroscience. Psychology Press.
New York and Hove. 2005. p.189.
[26] Ibid. p.165.
[27] The processes are initiated from effectors, which are
regulated by internal sensory information. A failure in the maintenance of the
functional parametric environments is a pathology.
[29] Ibid.
[30] Ibid. p.p.18-19.
[31] Ibid. p.27.
[32] Cf. Lane, Nadel, and Kaszniak. The Future of Emotion Research from the Perspective of Cognitive
Neuroscience. In Cognitive
Neuroscience of Emotion. Lane, Richard D. and Nadel, Lynn. Editors. Oxford
University Press. New York. 2002. p.408.
[33] Cf. Richard D. Lane. Neural
Correlates of Conscious Emotional Experience. In Cognitive Neuroscience of Emotion. Ed. Cit. p.363.
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