THE BRAIN AND BEHAVIOR*
PSYCHOLOGISTS, because of their interest in develop-
ing ways of explaining and predicting human behavior,
find it necessary to understand the physical and physiologi-
cal characteristics of human beings. Any scientific analysis
of behavior must take into consideration the structural fac-
tors or mechanisms which might be involved in the relation
between environmental conditions and behavior. A psychol-
ogy developed in ancient times, or in other parts of the
world, might have directed its attention to tire heart and
the circulatory system or to the diaphragm and the respira-
tory or “pneumatic” system (Magoun, 1958; Veith, 1958;
Woollam, 1958), but psychologists in Europe and America
during the past hundred years have been concerned with the
central nervous system as the relevant physiological mediator
between environment and behavior. Tire purpose of this
paper is to describe the neurophysiological model current
around 1900 which was proposed as such a mediating mecha-
nism and to contrast the simple, machine-like conception it
involved with the complex model which more recent neuro-
physiological work requires.
Neurophysiologists are in agreement in dating the begin-
ning of the modern period of research on the central nervous
system to the observation in 1870 by two German neurosur-
geons, Fritsch and Hitzig (1870), that an electrical current
applied to the surface of a dog’s cortex resulted in move-
ments of the legs on the opposite side of the body (cf. Fer-
rier, 1886, p. 223; Penfield & Rasmussen, 1950, p. 12; von
Bonin, 1950, p. 11; Konorski, 1958, p. 1102). The effect of
* Revised version of a paper presented on March 19, 1959, to
the Houston Philosophical Society.
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