Main trends of research in the social and human ... - unesdoc - Unesco

Psychology 239
derived from hereditary forms, but suppose real construction in the course of
which stimuli are certainly received from the functioning of the brain, but within
the functional framework and not from any innate ideas. What has been built at
the sensori-motor level must then be reconstructed and taken further at the
conceptual or thought level (for knowing how to perform an action and being
able to retrace it in one’s mind are quite different things) and, in the actual
matter of thought, what begins in the form of concrete operations directly
concerning objects is transposed only later onto the plane of abstract thought,
and so on.
In short, if there are close connexions between the nervous or physiological
structure in general and the cognitive structure, these represent multiple interac-
t ions between processes involving superimposed scales and not at all simple
reduction. Just as much should be said about the central mechanisms of motiva-
tion, impulses, emotions, etc., but as their study is developing very fast, it is not
possible in this chapter to give a clear overall picture.13
4. The physicalist trend and the various levels of perception
A second form of explanation that may lead to attempts at reduction charac-
terizes a fairly permanent trend in psychology, which, too, has led to a some-
what spectacular and very significant reversal of meaning of contemporary
trends in psychology as compared with past trends. While affectivity, habit
formation and certain aspects of the intelligence itself are obviously dependent
on the organism, other things, more especially perception and objective (and
so to speak depersonalized) forms of cognition may seem directly bound up with
the physical world, hence repeated attempts to link these mental processes to
physical processes. This trend has naturally been all the more marked since it
has sometimes been represented by authors who have been trained as physicists
before turning to psychology, such as Fechner in the last century and W . Kohler
today.
I. If I refer to Fechner, although he is now history, it is to underline once again
that the various trends in psychology begin as developments of an atomistic
nature before turning to structuralist interpretations. We have already noted
the profoundly atomistic nature of the first associationist views, while present
thinking on the subject of conditioning is marked, as we have seen, by cybernet-
icier even algebraic, probabilist structuralism. As far as the physicalist trend is
concerned, Fechner, after Weber and the Frenchman Bouguer, also wanted to
express simply the constant relation between sensations, considered in isolation,
and the physical quantities that they express subjectively, hence the famous
logarithmic law relating the stimulus to the sensation and which, though
approximate (Stevens even replaces it by a power function), has been rediscov-
ered in many biological contexts; it even governs the relations between light
intensity and the prints on a photographic plate (which shows its purely proba-
bilist-nature, this physical example being explained by the probability of the
photons and the silver salt particles of the plate meeting).