7. How would you rate your efficiency in study? Is it near your
physiological limit, on a plateau, or in a stage of rapid
improvement?

8. A practice experiment. Take several pages of uniform printed
matter, and mark it off into sections of 15 lines. Take your time
for marking every word in one section that contains both e and r.
The two letters need not be adjacent, but must both be present
somewhere In the word. Having recorded your time for this first
section, do the same thing with the next section, and so on for 12
sections. What were you able to observe, introspectively, of your
method of work and changes with practice. From the objective
observations, construct a practice curve.

9. Write brief explanations of the following terms:
practice
habit
higher unit
overlapping
plateau
physiological limit
insight
trial and error
negative adaptation
substitute stimulus
substitute response
conditioned reflex

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REFERENCES

Thorndike's _Animal Intelligence, Experimental Studies,_ 1911, reports
his own pioneer work in this field. See also Chapter X in the same
author's _Educational Psychology, Briefer Course_, 1914.

For other reviews of the work on animal learning, see Watson's
_Behavior_, 1914, pp. 184-250; also Washburn's _Animal Mind_, 2nd
edition, 1917, pp. 257-312.

For human learning and practice, see Thorndike's _Educational
Psychology, Briefer Course_, 1914, Chapters XIV and XV; also Starch's
_Educational Psychology_, 1919, Chapter XI.

For an experiment showing the acquisition of fears by a child, see
Watson and Raynor, "Conditioned Emotional Reactions", in the _Journal
of Experimental Psychology_, 1920, Vol. 3, pp. 1-14.

James's chapter on "Habit", in his _Principles of Psychology_, 1890,
Vol. I, is a classic which every one should read.

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CHAPTER XIV

MEMORY

HOW WE MEMORIZE AND REMEMBER, AND IN WHAT
RESPECTS MEMORY CAN BE MANAGED AND IMPROVED

So much depends on a good memory in all walks of life, and especially
in brain work of any sort, that perhaps it is no wonder that many
students and business and professional men become worried about their
memories and resort to "memory training courses" in the hope of
improvement. The scientific approach to this very practical problem
evidently lies through a careful study of the way in which memory
works, and the general problem may be ex