Re: Psychology and Science

From: Stevan Harnad (harnad@mulberry.psy.soton.ac.uk)
Date: Mon Oct 13 1997 - 20:21:04 BST


> On Mon, 13 Oct 1997, S.J.Foster wrote:
>
> individuals rely greatly on their brains as it provides
> a large capacity for storing information and controls functions such as
> sleep, language and memory etc:

I would say that individuals ARE their brains, rather than users of
them!

> but rather than just concentrating on
> the mechanics of the brain, psychology could (arguably) be called
> the scientific study of behaviour and conscience experience.

I can guess how we can study behaviour "scientifically" (though I'm not
sure what "science" means) but how do we study conscious experience
scientifically?

> There exists three main ways in which to study the brain and its
> functions:

So does this mean that psychology is the science of the brain? But then
what is neuroscience?

> Firstly invasive lesions could be carried out where small
> blocks of the cortex are either damaged, cut off or isolated to see how
> they are influenced by other parts.

Any volunteers for being studied this way? (I guess you meant animal
brains, right?)

> With this type of technique there
> are ethical problems as operations are often done ,only under local
> anesthetic, but lesions are not necessarily irreversible and sometimes
> they can occur naturally eg: through strokes.

The only tampering with the living human brain that is allowed is
tampering in trying to fix something (like epilepsy). The rest of the
work on human brain damage is based on lesions that happened on their
own accord, not those that were induced by brain surgeons. That field is
called "neuropsychology": Clinical neuropsychology is the study of ways
to understand and help people with brain damage. Cognitive
neuropsychology is the study of the damaged brain to better understand
the intact brain.

> the second technique works by artificial/ electrical stimulation, where
> electrical waves are sent into the brain to detect its functions and
> even trigger off behaviours eg: hunting reflexes. With this method there
> is no evidence of permanent damage, but you can not always be sure what
> area of the brain is being studied, or how far the current is flowing
> because so many neurons are connected, plus also it is unnatural.

And very little of this is justified in humans, hence very little is
done.

> The last technique is to record naturally occurring functions and this
> can be done through the use of an EEG machine where electrodes are
> placed next to the skin, stimulated and the amount of electrical
> activity recorded.

Except that trying to understand how the brain works on the basis of
brain waves on the surface of the scalp is (as has many times been
said) like trying to understand how a factory works from the the smoke
coming out of its chimney.

This is not entirely true any more, as there are now more sophisticated
ways of studying brain waves, and there are other kinds of brain
imaging too, including Positron Emission Tomography (PET scans) and
Nuclear Magnetic Resonance (NMR) imaging. See:
http://www.cogsci.soton.ac.uk/bbs/Archive/bbs.posner.html

> By studying the mind, psychologists aim to uncover facts describe
> them,understand them, predict and thus control the interaction between
> the psyche, environment and behaviour.

Apart from brain injuries and brain imaging, how do psychologist do all
that?

> Psychology is scientific in some respect as it relies upon quantitative
> methods by which to obtain empirical evidence (eg: through experiments)
> and investigators aim to be objective, plus also intend to answer
> questions (hypotheses) about their chosen topics.

Good, but still a bit too dictionary-like: How do they do these things,
and what are examples?

> Psychology differs to maths, as there ideas are able to be 'proven'
> (eg: 2+2 always =4) whereas data collected from psychologists can't
> necessarily 'prove' anything as living organisms are highly complex and
> don't always produce the same responses.

The reason there is no proof in Psychology is not because animals are
unpredictable, because in physics and chemistry there is no proof
either.

> This is the main distinction
> between psychology and other sciences (eg:chemistry). Due to this,

What is that difference? if it's not proof/no-proof, is it
complexity/simplicity? Do you think that we are more complex
than a galaxy, or even a thunderstorm?

> problems are faced in finding suitable techniques of measurement because
> of practical, moral and ethical limitations (eg: finding a representative
> sample where brain lesions can be done).

How eager you are to cut up people's brains! Lesions can only been done
when they are to help the patient!

> Psychology, as a result could
> be classed as 'nearly scientific' as researchers often use subjective
> methods (eg:qualitative questionnaires) which correlate well with
> objective measures to give an all round understanding to behaviour.

You need to give examples. This was a good discussion, but followed the
text too much. After a few weeks in this seminar you'll be thinking for
yourself.



This archive was generated by hypermail 2b30 : Tue Feb 13 2001 - 16:24:19 GMT