Here’s a list of Young’s scientific publications. I’ve highlighted five with titles which, to me, seemed relevant to the question.
1918
An experimental study of mixed feelings. American Journal of Psychology, 29, 237-271.
The localization of feeling. American Journal of Psychology, 29, 420-430.
Tunable bars, and some demonstrations with a simple bar and a stethoscope. Psychological Bulletin, 15, 293-300.
1921
Pleasantness and unpleasantness in relation to organic response. American Journal of Psychology, 32, 38-53.
The vibrations of a tuning fork. Science, 54, 604-605.
1922
Movements of pursuit and avoidance as expressions of simple feeling. American Journal of Psychology, 33, 511-526.
Series of difference tones obtained from tunable bars. American Journal of Psychology, 33, 385-393.
1923
Constancy of affective judgment to odors. Journal of Experimental Psychology, 6, 182-191.
A differential color mixer with stationary disks. Journal of Experimental Psychology, 6, 323-343.
1924
The phenomenological point of view. Psychological Review, 31, 288-296.
1925
The coexistence and localization of feelings. British Journal of Psychology, 15, 356-362.
The phenomena of organic set. Psychological Review, 32, 472-478.
1927
With R. Gundlach & D. A. Rothschild. A test and analysis of set. Journal of Experimental Psychology, 10, 247-280.
An analysis of observation in the field of affective psychology. In, Proceedings and Papers of the VIIIth International Congress of Psychology. Groningen: Noordhoff.
Studies in affective psychology: I. The localization and spatial character of pleasantness and unpleasantness. American Journal of Psychology, 38, 157-167.
Studies in affective psychology: II. The case for the affective processes. American Journal of Psychology, 38, 167-175.
Studies in affective psychology: III. The “trained” observer in affective psychology. American Journal of Psychology, 38, 175-185.
Studies in affective psychology: IV. The logic of affective psychology. American Journal of Psychology, 38, 186-189.
Studies in affective psychology: V. The framework of psychology. American Journal of Psychology, 38, 189-193.
1928
Auditory localization with acoustical transposition of the ears. Journal of Experimental Psychology, 11, 399-429.
Class-room demonstration of double images. American Journal of Psychology, 40, 497.
Studies in affective psychology: VI. Preferential discrimination of the white rat for different kinds of grain. American Journal of Psychology, 40, 372-394.
Studies in affective psychology: VII. Conflict of movement in relation to unpleasant feeling. American Journal of Psychology, 40, 394-400.
1930
Studies in affective psychology: VIII. The scale of values method. American Journal of Psychology, 42, 17-27.
Studies in affective psychology: IX. The point of view of affective psychology. American Journal of Psychology, 42, 27-35.
Studies in affective psychology: X. Some general conclusions. American Journal of Psychology, 42, 35-37.
1931
The role of head movements in auditory localization. Journal of Experimental Psychology, 14, 95-124.
Sex differences in handwriting. Journal of Applied Psychology, 15, 486-498.
With W. L. Morgan & E. H. Kniep. Studies in affective psychology: XI. Individual differences in affective reaction to odors. American Journal of Psychology, 43, 406-414.
With W. L. Morgan & E. H. Kniep. Studies in affective psychology: XII. The relation between age and affective reaction to odors. American Journal of Psychology, 43, 414-421.
1932
The relation of bright and dull pressure to affectivity. American Journal of Psychology, 44, 780-784.
Relative food preferences of the white rat. Journal of Comparative Psychology, 14, 297-319.
1933
Relative food preferences of the white rat. II. Journal of Comparative Psychology, 15, 149-165.
Food preferences and the regulation of eating. Journal of Comparative Psychology, 15, 167-176.
With R. K. Compton. A study of organic set: Immediate reproduction of spatial patterns presented by successive points to different senses. Journal of Experimental Psychology, 16, 775-797.
Memory for pleasant, unpleasant, and indifferent pairs of words. Journal of Experimental Psychology, 16, 454-455.
Motivation of human and animal behavior. Ann Arbor, Mich.: Edwards Brothers.
1936
Motivation of behavior, the fundamental determinants of human and animal activity. New York: Wiley.
1937
A group experiment upon the affective reaction to odors. American Journal of Psychology, 49, 277-286.
Is cheerfulness-depression a general temperamental trait? Psychological Review, 44, 313-319.
Laughing and weeping, cheerfulness and depression: A study of moods among college students. Journal of Social Psychology, 8, 311-334.
A study upon the recall of pleasant and unpleasant words. American Journal of Psychology, 49, 581-596.
Reversal of auditory localization. Psychological Review, 44, 505-520.
1938
With W. F. Thomas. Liking and disliking persons. Journal of Social Psychology, 9, 169-188.
Preferences and demands of the white rat for food. Journal of Comparative Psychology, 26, 545-588.
An hypothesis concerning the mechanism of appetite. Psychological Bulletin, 35, 716-717.
1940
Reversal of food preferences of the white rat through controlled pre-feeding. Journal of General Psychology, 22, 33-66.
With J. R. Wittenborn. Food preferences of rachitic and normal rats. Journal of Comparative Psychology, 30, 261-276.
Emotion in man and animal, a psychological interpretation. Ann Arbor, Mich.: Edwards Brothers.
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The study mentioned in your first link is most likely “Preferences and demands of the white rat for food”, by Paul Thomas Young. This paper is includes a section tantalisingly named “Spatial factors in the feeding behavior of rats”, which turns out not to be related to Feynman’s story:
Young’s biographical note does not include a list of papers, but his Distinguished Scientific Contribution Award note does:
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