The Brain and Behavior 55
which assumes regularity and precision o£ anatomic arrange-
ment” (Jeffress, 1951, p. 70).
(2) The studies designed to examine the sensory and motor
processes relating to cortical stimulation were primarily con-
cerned with the kinds of sensations and movements elicited.
Penfield’s observations are particularly pertinent in this con-
text: “The sensation elicited was described as tingling, as
sense of movement when no movement could be observed,
and on the negative side as numbness. The words pain,’
‘cold,’ and ‘blood rushing,’ which may mean heat, were used
only occasionally. Apparently no patient found it disagree-
able. No forced reactions appeared as after painful stimula-
tion. These are elements of sensation which do not carry with
them specific memories. The patient knew accurately only
where the sensation semed to be. He never suggestd that
something rough or smooth or warm or cold had actually
touched the part, nor did he believe that someone was mov-
ing the part” (Penfield & Rasmussen, 1950, pp. 216-217).
“Some of the movements are crude, others complicated,
but they are all elementary. Thus, the movements of the
contralateral leg and arm are those of simple flexion or exten-
sion. The hand opens or closes; no more. In the lower por-
tion of the sensorimotor strip, however, stimulation may pro-
duce the following coordinated acts, which are not restricted
to contralateral parts but are bilateral: (1) vocalization, a
coordinated act carried out by skillful activation of mouth,
pharynx, larynx, diaphragm, and abdominal musculature;
(2) mouth movements as though eating or sucking, associated
with salivation and swallowing; (3) turning to one side with
conjugate deviation of the two eyes. The baby is able to do
all of these things at birth, or not long afterward. But there
is, in all of this, none of the acquired skillful foot movements
of the dancer, nor any of the manifold delicate performances