MINUTE ANALYSIS OE CORTICAL CENTRES. 
1G3 
It seemed to us highly important, as bearing on this point, to note the order of 
movement of the different segments of the limb,—in fact, the “ march,” as it has been 
termed by Dr. Hughlings Jackson, of the nerve discharge,—since we consider that 
a complete series of observations of this kind would enable us to construct a definite 
scheme which would show at a glance where certain primary movements are really 
centralised. 
By this we mean that we applied the electrodes to the cortex just long enough to 
evoke movement in one joint only, and then noted which moved first, and in what 
direction. This first movement we considered to be the primary or fundamental 
movement in the given portion of cortex stimulated. (The current employed in every 
case was only just adequate to produce such movement, and the secondary coil 
was usually 10 cm. distant from the primary coil.) 
On fig. 8 is exhibited that joint in which primary movement occurs in each 
portion of the area. 
In taking each joint separately, it is found that the shoulder presents priority of 
movement in the centres 1, 1', 11 ; while the wrist is the first to move when we 
stimulate the centres 2, 2', 12, 13, 3'. It is important to notice that the elbow does 
not present any absolute priority of movement over the other joints, for its only 
approach to priority is seen at centres 8, 8', and 9, where it is associated with, and 
shares this action synchronously with, other joints, viz., the thumb and wrist. With 
regard to the fingers alone, the same thing is to be observed, viz., that they are not 
represented in primary movement in the cortex, and indeed are only associated once 
with a true primary movement, viz., in centre 12. Starting now with the series of 
joints moved as represented schematically in fig. 8, we will take up the order in which 
the other joints of the limb are secondarily moved. 
Tabulating these joints in the order of centres stimulated, we have the following 
list:— 
