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Embodied Embedded Cognition

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The term Embodiment refers to the idea that the internal milieu of the body (such as hormone levels or other homeostatic functions) plays an important role in the processes usually attributed to more higher cognitive processes. This influence is probably achieved through manipulation of emotional states, as suggested by Damasio (1994).

“Embedded” describes the quality of reciprocal interaction between the body and the physical world, which in turn gives rise to cognitive processes.

For a long time the human mind was thought to be totally different from those of animals. It was assumed that sensory data is elaborated by the human mind and stored in a network of abstract representations that are of a semantic structure. The currently dominant paradigm sees the human mind as essentially being a computational-representational system. Within the current paradigm the ultimate explanation for behavior lies within the virtual cognitive functions (software) that are computed by the brain (hardware). Those virtual cognitive functions handle the sensory input, compute a solution and perform output (behavior).

In opposition to this paradigm, the theory of Embodied Embedded Cognition postulates that the difference between the hardware and the software is a semantic one. The metaphor Hardware describes the materialistic, biological aspects of the brain, whereas the metaphor software focuses on the functional aspects. This does not mean that these are two different “things”. Body, brain and world form a system. The intelligent behavior arises from the interaction of the different parts. No a-modal representational system is required to connect a meaning to a symbol, but only a modal system of representations (see also Rolls (1997)).

Specific neurons are activated when they perceive a stimulus, let’s say a car. Through repetition, neuronal activity gets connected to the “real thing” (the car). When enough items of one category have been perceived, we are then able to generate a prototype (Simulators). The idea of this prototype consists of the neural activity that most of the items in one category share. You can also start with the prototype and imagine how an unknown face would look like, by slightly changing the neuronal “fingerprint” of the prototype.

Is there scientific evidence for the Embodied Embedded Cognition Theory?

First of all the a-modal representation has, per definition, all capabilities of a Turing-machine. It is therefore able to explain everything and thus nothing, so the merit as scientific theory is questionable.

Secondly, Embodied Embedded Cognition Theory has postulated some specific hypotheses that have been tested experimentally. For example, specific predictions have been made concerning the spread of related words in an a-modal, a semantic network and a modal network. Those specific predictions have been shown to be true for the human representational system (see Wong & Yon (1991). This has greatly increased the scientific weight of the theory. In comparison, the a-modal theory has never generated this kind of specific hypotheses.

Hopefully greater resolution of brain scans will help to uncover more of the many secrets the human mind still has to offer.

References

Damasio, A.R. (1994). Descartes’ Error: emotion, reason, and the human brain. New York: Grosset/Putnam.
Rolls, E.T. (1997). “Consciousness in neural networks”. Neural Networks, 10, 1227-1240.

Wong, S.K M. & Yao, Y. Y. (1991). A probabilistic inference model for information retrieval. Transactions on Information Systems 16, 301-321.

Written by Martin Metzmacher

October 9, 2007 at 1:16 pm

Why Evolutionary Psychology is a Valid Approach for Studying Human Behaviour.

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I will first demonstrate that in behavioural science there is no alternative explanation to evolution when exploring the whole causal chain that leads to a specific behaviour. Secondly I will show that the implication of this perspective yield results also in studies that focus on a more narrow subject. Last I hope to refuse the critics who claim that EP is build on unscientific presumptions.

As humans we are drawn to find causality. Our automatic way of thinking even leads us to see connections where none exists. It is usually not obvious that causal relations can be of different quality. Consider this: If I say: “The stone broke the window.” then I have made a proper causal statement. But when I say “The girl threw the stone, that broke the window.” I have somehow explained more, as I went further backwards along the causal chain of events, which resulted in the broken window. In a scientific reality that defines time s a linear function, there must be an ultimate starting point of the chain of causal events. Explanations or hypotheses that cover the whole length of the causal chain from beginning to end can be considered an “ultimate explanation”.

Until the middle of the 19th century the starting point of this causal chain was considered to be God. But in 1859, Darwin proposed a process, natural selection, that could explain how different species could evolve. A little later Popper proposed that every theory must be falsifiable to yield any scientific merit. Therefore the theory of a God as a creator has been discarded as object of scientific research. Within the scientific community today no other processes are known that could explain the evolution as well as Darwin’s theory. Therefore I draw the conclusion that if one wishes to make an ultimate explanation of any process concerning human behaviour, one must adapt the perspective of evolutionary psychology.

A scientific theory can not be verified, but research can accumulate support for specific idea. The theory under investigation is used to generate hypothesis, which then can be falsified. If various parts of the theory hold up against critical research, the theory can be presumed to be correct. Adopting the perspective of Evolutionary Psychology has brought tremendous progress to many areas of scientific research. The study of animals can offer insights into human behaviour. This is not only true for the cognitive and social processes that have been studies in great apes, but also for the more basic biological processes that have been studied in animals with only a few thousands neurons. For example the insights into the neuronal structure of the cockroach has greatly benefited research in artificial intelligence. It is a great advantage that evolution theory can be applied to all processes whether they are mechanical or historical. In this regard, Evolution Theory brings together biology and many social science and might one day serve as framework to incorporate findings from different scientific areas into one theory.

Critics often state the problem that Evolutionary Psychology is based on presumptions about human life, that can not be verified. Although historians and anthropologists are able to offer a vivid picture of human life in a former time they might plainly be wrong on important facts. Of course this would form a problem to all theories that rely on those presumptions, including Evolutionary Psychology. In my view this problem is not a problem at all. In constructing hypotheses about evolution (for example the social structure of the homo neandertalis) the same principles apply to any other hypothesis: Only if enough evidence has been accumulated from different sources and with different tools the hypothesis can be used as possible explanation. Setting up an experiment without a hypothesis and then arguing backwards to fit an evolutionary picture is clearly against proper scientific procedures. So when criticizing experiments of Evolutionary Psychology one should always be clear on what is imperfect: The theory itself, which in my opinion can only be proven by falsifying deducted hypothesis, or the methodology used.

Therefore I conclude that Evolutionary Psychology, when used within the proper scientific guidelines, is a very interesting perspective that entails great potential for all science dedicated to biological life. The most important function of the evolutionary perspective in my opinion is the stimulation of and focussing of research towards an ultimate theory of life.

Written by Martin Metzmacher

September 27, 2007 at 11:09 am