2. Is the reaction time experiment, as described in the text, an introspective or an objective experiment?
3. Mention two cases from common life that belong under the "simple reaction", two that belong under "choice reaction", and two that belong under the "associative reaction".
4. Arrange the reflexes mentioned in the text under the two heads of "protective" and "regulative".
5. Draw diagrams of (a) the neurone, (b) a synapse, (c) a reflex arc, and (d) a coördinated movement. Reduce each drawing to the simplest possible form, and still retain everything that is essential.
6. What part of the nervous system lies (a) in the forehead and top of the head, (b) in the very back of the head, (c) along the base of the skull, (d) within the backbone, (e) in the arm?
7. Using a watch to take the time, see how long it takes you to name the letters in a line of print, reading them in reverse order from the end of the line to the beginning. Compare with this time the time required to respond to each letter by the letter following it in the alphabet (saying "n" when you see m, and "t" when you see s, etc.). Which of these two "stunts" is more like reflex action, and how, nevertheless, does it differ from true reflex action?
8. The pupillary reflex. Describe the reaction of the pupil of the eye to light suddenly shining into the eye. This response can best be observed in another person, but you can observe it in yourself by aid of a hand mirror. On another person you can also observe the "crossed" pupillary reflex, by throwing the light into one eye only while you watch the other eye. What sort of connection do you suppose to exist between the two eyes, making this crossed reflex possible?
9. The lid reflex, or wink reflex, (a) Bring your hand suddenly close to another person's eye, and notice the response of the eyelid, (b) See whether you can get a crossed reflex here, (c) See whether your subject can voluntarily prevent (inhibit) the lid reflex, (d) See whether the reflex occurs when he gives the stimulus himself, by moving his own hand suddenly up to his eye. (e) What other stimulus, besides the visual one that you have been using, will arouse the same response?
REFERENCES
C. Judson Herrick, in his Introduction to Neurology, 2nd edition, 1918, gives a fuller and yet not too detailed account of the neurone in Chapter III, and of reflex action in Chapter IV.
Percy G. Stiles, in his Nervous System and Its Conservation, 1915, discusses these matters in Chapters II, III and IV.
Ladd and Woodworth's Elements of Physiological Psychology, 1911, has chapters on these topics.
CHAPTER III
REACTIONS OF DIFFERENT LEVELS
HOW SENSATIONS, PERCEPTIONS AND THOUGHTS MAY BE CONSIDERED AS FORMS OF INNER RESPONSE, AND HOW THESE HIGHER REACTIONS ARE RELATED IN THE NERVOUS SYSTEM TO THE SIMPLER RESPONSES OF THE REFLEX LEVEL.
Having defined a reaction as an act of the individual aroused by a stimulus, there is no reason why we should not include a great variety of mental processes under the general head of reactions. Any mental process is an activity of the organism, and it is aroused by some stimulus, external or internal; therefore, it is a reaction.