FIG. 3. DIAGRAM SHOWING AFFERENT (SENSORY) NEURONE WHICH INFLUENCES DIRECTLY THREE EFFERENT (MOTOR) NEURONES.

The arrows show the direction of the impulse when the sense organ (SO) is stimulated, Movement is effected when the impulse reaches the muscles (M).

attending the response G will analogously increase the readiness of synapse DG for conducting. If like results be repeated often and consistently enough, eventually the stimulation will choose immediately the path ADG in preference to any other and the response G will then come promptly and surely.

5. Secondary Neurone Connections

[THORNDIKE, E. L., Educational Psychology, Vol. I, pp. 141-142; 307308. New York, Teachers College, Columbia University, 1913.] (Adapted.)

Mental activity is satisfying to man; mental emptiness is annoying. The brain of man contains millions of neurones which crave stimulation. They are in "readiness to conduct," though no immediate gratification of any more practical want follows their action.

Native satisfiers and annoyers referred to above as well as many others belonging to such original behavior series as have to do with food-getting, food-seeking, danger-avoiding, and the like, involve a direct bond of neurone connection between the suitable stimulating situation and its appropriate response. Thus, the presence of suitable food to the mouth stimulates through its own direct bond the masticating response. Acquired bonds may also crave exercise.

In additions to direct bonds, whether original or acquired, between situations and responses, there are original tendencies to make and enjoy making secondary connections. For example, a child likes to see and hear a rattle. Direct bonds are at work. But to handle and shake the object himself so as to produce the noise is still greater satisfaction. Hearing the rattle when he shakes it is an example of a secondary connection. It represents the action of the neurones concerned in the child's manipulations, those concerned in his sensations and those concerned in connecting the latter with the former. To do something and have something happen is, other things equal, instinctively satisfying. There are many concrete forms of secondary connections. Making plans and getting conclusions, making imaginary people and thereby getting further imaginations of how they would act, as well as making movements and thereby getting sensations, are satisfying. They are originally satisfying in the sense that nature gives satisfyingness to the connection as soon as training and education give the ability to make the plan or form the image, etc.

Secondary connections have great significance for both improving and satisfying human wants. Those bonds or connections in which the sensory situation is replaced by an abstract plan, and the immediate muscular response by a contemplated action, tried out on the level of thought only, will, in the long run, do most for satisfying human wants. Each secondary connection can do the work of thousands of gross concrete behavior-series, providing for situations before they are met, for elements of situations never encountered by themselves, and for groups of situations whose essential similarity the more animal-like connections could never reveal. "Furthermore, these tendencies to secondary, or higher,' connections may rise free from the appetites of the single creature who exercises them and deal with the world in the interests of all men. Work and play with 'ideas can be impersonal and ideal to an extent and to a degree that would never be attained by direct responses to the concrete situations themselves."

Again, McDougall says: "We may say, then, that directly or indirectly the instincts are the prime movers of all human activity; by the impulsive force of some instinct (or some habit derived from an instinct), every train of thought, however cold and passionless it may seem, is borne along toward its end and every bodily activity is initiated or sustained. ... Take away these instinctive dispositions with their powerful impulses, the organism would become incapable of activity of any kind; it would lie inert and motionless like a wonderful clockwork whose mainspring had been removed or a steam-engine whose fires had been drawn" (p. 45).

McDougall's position is not as extreme as it appears at first sight for he admits that habits derived from instincts are motive factors. But others like Woodworth, are disposed to believe that there are habits, possessing driving potency, which are really not derived from instincts.

7. Stimuli and Responses; Every Mental Act Is Motor [WOODWORTH, Robert S., Psychology-A Study of Mental Life, pp. 46– 47. New York, Henry Holt & Co., 1921.]

The main point of this discussion is that all mental phenomena, whether movements, sensations, emotions, impulses or thoughts, are a person's acts, but that every act is a response to some present stimulus. This rather obvious truth has not always seemed obvious. Some theorists, in emphasizing the spontaneity and "self-activity" of the individual, have pushed the stimulus away into the background; while others, fixing their attention on the stimulus, have treated the individual as the passive recipient of sensation and "experience" generally. Experience, however, is not received; it is lived, and that means done, only it is done in response to stimuli. The concept of reaction covers the ground.

8. Different Sorts of Stimuli

[WOODWORTH, Robert S., Psychology-A Study of Mental Life, p. 47. New York, Henry Holt & Co., 1921.]

To call all mental processes reactions means that it is always in order to ask for the stimulus. Typically, the stimulus is an external force, or motion, such as light or sound, striking on a sense organ. There are also the internal stimuli, consisting of

changes occurring within the body and acting on the sensory nerves that are distributed to the muscles, bones, lungs, stomach and most of the organs. The sensations of muscular strain and fatigue, and of hunger and thirst, are aroused by internal stimuli, and many reflexes are aroused in the same way.

9. Responses May Consist of Movement or of the Prevention of Movement

[FREEMAN, Frank N., How Children Learn, pp. 3-4. Boston, Houghton Mifflin Co., 1917.]

When we speak of responses one is instantly led to think of active responses consisting of outward movements. They are the most obvious, it is true, but the prevention of a movement is a response to a situation as truly as is the making of a movement. If a child is sitting in a schoolroom and hears a circus parade outside, the instinctive response to this insistent form of stimulus is getting up and looking out of the window. If the child remains in his seat he is responding to the school situation by actively preventing the movement of getting up and going to the window. This checking of a response is called "inhibition." If we compare the adult with the child, or the highly civilized person with the primitive man, we find that education has consisted in a great many instances in inhibiting the natural, spontaneous movements which are made in response to certain stimuli. On the other hand, primitive man has certain inhibitions which civilized peoples have outgrown. Children of one community have to acquire certain sorts of inhibition and children of other communities must acquire other sorts. The effect of the action of the brain, which is the most highly developed part of the nervous system, is to slow down the mechanical reflex movements of the spinal cord which are of an instinctive nature. When the brain of the frog is severed from the spinal cord its foot will be withdrawn from contact with a hot object more quickly than when the brain and the cord are connected in the normal way.

10. Watson's Studies of the Conditioned Reflex [WATSON, J. B., and RAYNER, R., "Studies in Infant Psychology," Scientific Monthly, December, 1921, pp. 493-515.] (Adapted.)

In some of his earlier experiments, Watson gave an electric stimulation of the finger, the experimenter sitting in a different room provided with . . . keys by which he

could give at will the sound of a bell coincidentally with the electric current or separate from the current.

When beginning with a new subject, he first sounded the bell to see if this would directly produce the reflex. He did not find in a single instance the reflex being called out prior to the electric stimulation. Next the shock and the bell were given simultaneously for five trials, then the bell alone was tried again. If there was no reaction, then five more stimulations were given simultaneously as before, and so on. Не found that the conditioned reflex appears at first, say once, and then disappears. The electric stimulation is then again given. It may next appear two or three times in succession and then disappear, but after a time it appears regularly without the shock when the bell is sounded. He was able to secure good conditioned reflexes in from fourteen to thirty combined stimulations.

In his joint investigation with Rayner, we are given the following résumé:

If the subject sits with the palm of his hand open upon a metal plate and his middle finger upon a metal bar and an electrical current is sent through the circuit thus completed by the hand, the finger will fly upward from the metal bar the moment the electric shock is given. This painful stimulus is thus the native or fundamental stimulus which calls out the defensive reflex of the finger. The sight of an apple or the sound of a bell will naturally not produce this upward jerk of the finger. On the other hand, if the bell is sounded or the colored object is shown the moment the electric current is completed through the hand, and this routine is repeated several times, the situation becomes wholly different. The finger begins to jerk up reflexly now and then when the bell is rung or the colored object shown even if the electrical current is not sent through the hand. After a longer or shorter period of training the colored object will cause the jump of the finger just as inevitably as does the current.