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Why are we happy?

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Why are we happy? Interesting thoughts on happiness by Dan Gilbert.

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Written by Martin Glanert

June 11, 2009 at 7:09 pm

Posted in Philosophy

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Free Will and Consciousness

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The topic of free will has been a central issue since the beginning of philosophy: How do rational agents exercise control over one’s actions and decisions.

In “the precise of the illusion of conscious will” (2004), Daniel M. Wegner explores the idea of apparent mental causation. He argues that if a thought arises just before an action takes place, if it is consistent with the action and the exclusive salient cause of the action, we will regard ourselves as the agent of the behaviour.

Libet (1985) showed in his experiment that conscious perception of reality lives about half a second in the past. He concluded that we could not have free will, since our brain already comes into action, before we have consciously engaged in the idea. He offered however, as some kind of last hope, the veto right of the free will. The same effect has also been found by Cunningham et al. (2001). In a computer game, similar to space invaders, participants had to use a computer mouse with a half second delay. When the delay was removed, the participants reported that the hand moved before they had consciously made that decision.

So does free will exist? If we live in the past and we falsely attribute behaviour to ourselves that we had no influence of, how can we propose that we are consciously in control of our behaviour? Is consciousness but an epiphenomenon?

I believe that these findings have to be interpreted very carefully. Although they offer intriguing hypothesis about how and why we act, we should not, in a hurry, remove consciousness from the picture. When lifting your finger, as done Libet’s experiment, the motor program running will be automatic, although the decision to do so might be conscious. But do participants really make their conscious choice a few milliseconds before the execution? I believe that they will execute the task in a mental simulation as soon as they are told what will be expected of them in this experiment. So the “causal decision” to execute the movement might be the activation of the action potential itself, not the conscious report of the decision to life the finger. The original decision to lift the finger at that time might have occurred much earlier. The ultimate decision to do so, by putting the body in such a state as to engage in this behaviour, was conscious.

I can only speculate how this mechanism actually could word, but in the computer world there is something called “cronjob”. This is an automatic program that is set to run at a specific time. Its much like always taking your medication at a specific time in order not to forget it. After a while you will remember it automatically at the given time. Thus consciousness might be able to implement such timed processes. If you think about consciousness pulling the string in the background, the half-second delay of the perception does not pose a huge problem. It does however, if free will necessarily requires consciousness to be online “in realtime” to make decisions.

In the computer experiment of Cunningham et al., involving the mouse delay, it is important to plan ahead because the participants know that they will have to cope with a delay. They ordered an action before it actually took place. They did so consciously and also successfully. We might just have adjusted to that specific delay between action and perception very well, because it feels natural to us. As long as consciousness can rely on automatic processes to carry out the proper motor behaviour, it does not need control in real time. Nørretranders (1999) also believes that speed is an important issue; he believes that “ Things that need to happen quickly happen subconsciously.”. Because adjustments of motor behaviour do not require conscious thought, they are not subject to the 500 ms delay.

Backdating perceptions might rather have other practical implications, for example to enhance structuring the environment in meaningful ways. The results of Wegner’s study can be interpreted in this way. Although Wegner’s studies show that our attribution of agency to action can be fooled, It might rather be the case that perception is fooled. I am not convinced that this requires the necessary conclusion that we do not have free will. As seen with the mouse delay, the “natural perception delay” can be altered. In the patient with clinical condition this alteration might include all senses and be persistent. I therefore conclude that consciousness is not an epiphenomenon, but an integral part in the selection of behaviour.

References

Libet, B. (1985). Unconscious cerebral initiative and the role of conscious will in voluntary
action. Behavioral and brain sciences 8:44, 529-566.

Nørretranders, T. (1999). The User Illusion, Penguin.

Wegner, M. (2004). Précis of The illusion of conscious will. Behavioral and brain sciences, 27, 1-11.

Written by Martin Glanert

November 7, 2007 at 1:14 am

The Whorfian Hypothesis: Language and Thought

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Where are all the Eskimos gone?

The question of language and though and its reciprocal influence has been discussed countless times. It goes back all the way to the Greeks and probably even further. In the last 30s of last century the businessman and linguist Benjamin Whorf postulated what would be know as the Whorfian-Hypothesis. His hypothesis can be split into a strong version, called linguistic determinism and a somewhat weaker version called linguistic relativism. Linguistic determinism states that our thinking and behaviour causally depends on the structure of our language. Linguistic relativism postulates a relationship between language and thought, but rejects the idea that this relationship necessarily needs to be causal.

Today most scientists, believe that the strong version of the Whorfian hypothesis, as well as the opposite, the claim that language has no influence on thought, is wrong. Even stronger, the theory is thought to be non-scientific, because of circular reasoning, as Steven Pinker (1994). points out in his book The Language Instinct: “Eskimos speak differently so they must think differently. How do we know that they think differently? Just listen to the way they speak!”. In the 1960s, when Noam Chomsky’s work on universal grammar became popular, most scientists turned away from the Whorfian hypothesis, but advances in the field of cognitive psychology in the early 90’s sparked renewed interest. Since then an important shift has occurred in this field of research, as more basic cognitive processes such as spatial orientation and memory have been put on the agenda of the researchers. I am now going to present several pieces of empirical evidence in favour of linguistic relativism.

Memory

Capacity in short-term memory is limited. It therefore makes sense to symbolise complicated constructs in the short term memory and store the complete information of the construct concerned in long term memory (that is what language actually does). The influence of language might therefore for some part be mediated by memory. And indeed there is evidence that language influences information stored in memory. One interesting paradigm to test this are colour perception. Participants were presented with non-prototypical (turquoise) chips and, after a delay, had to pick the right one (Schooler, 1990). Participants that had been forced to label the colour as either blue or green performed worse on the retention task (in the direction of the forced label) than participants that had not labelled the colour of the chips. Interestingly the effect disappeared when participants where forced to use the label blue-green.

Spatial orientation

Whereas in most western languages the dimension of time is semantically situated on a horizontal plane, this is not the case for Chinese. In Chinese the dimension of time spans on a vertical plane and indeed Chinese participants in an experiment by Boroditsky (2001) were faster to confirm that April comes after March if they had previously been primed with a vertical array of objects. On the contrary, English participants were faster, when presented with a horizontal array of objects.

Categorization

Higher order categories seem to be consistent throughout different languages (at least when the objects at hand are equally used in both societies), but this is not the case with lower order categories. In an experiment by Ameel (2005) it was shown that in French and Dutch bilingual speakers (from Belgium, thus sharing one cultural background) the categories used to classify objects (bottles and dishes) shared features of both the naming-pattern used by French native speakers and by Dutch native speakers. The researchers therefore concluded that the classification of objects not only depended on the commonalties between the objects, but also on language-specific factors.

Self-perception

In a study by Kemmelmeier and Cheng, bilingual Students from Hong Kong filled in Singelis’s independent and interdependent self-construal scales in English as well as in Chinese. As hypothesised there was significant difference in the self-construal of the students between the two languages. Describing themselves in English, students attributed a more independent self-construal to themselves, whereas in Chinese their self-construal was more interdependent. Kemmelmeier and Cheng concluded that language can serve as a cognitive cue to prime or reinforce culturally normative self-construals. This is also supported by a lot of episodic evidence from people (including me – especially when talking and thinking French) feeling like a different person, when talking in a different language.

Conclusion

The renewed interest of science in the Whorfian-theory has generated many interesting research findings. New paradigms and techniques, as well as the fast-paced development of cognitive neuroscience, have opened new doors for the researchers. However there is still much room for new research and specification of old findings. Research between different languages is mostly cross-cultural research, inviting numberless alternative explanations. Because of that research findings will need to be replicated in designs using bilinguals as participants. Furthermore, as the research on language and memory has shown, we will need to specify which cognitive processes actually cause the influence of language on though and how these mechanisms work. At the end of this search we might even meet up with the lost Eskimos.

References

Ameel, E., Storms, G., Malt, B. C., & Sloman, S. A. (2005). How bilinguals solve the naming problem. Journal of Memory and Language, 53, 60–80.

Boroditsky, L. (2001). Does language shape thought? Mandarin and English speakers’ conceptions of time. Cognitive Psychology, 43, 1-22.

Kemmelmeier, M., Cheng, B. (2004). Language and Self-Construal Priming: A Replication and Extension in a Hong Kong Sample. Journal of Cross-Cultural Psychology, 35, 705-712.

Pinker, S. (1994). The Language Instinct. New York, US: William Morrow and Company.

Schooler, J. W., & Engstler-Schooler, T. Y. (1990). Verbal overshadowing of visual memories: Some things are better left unsaid. Cognitive Psychology, 22, 36-71.

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 Glanert

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 Glanert

September 27, 2007 at 11:09 am