1. BRADLEY, K. The effect of relative word frequency in pairedassociate learning on duration thresholds of nonsense syllables. Unpublished research paper, University of Arkansas, 1965.
2. BRUNER, J. S., & GOODMAN, C. C. Value and need as organizing factors in perception. J. abnorm. soc. Psychol., 1947, 42, 33–44.
3. BYRNE, D. The repression-sensitization scale: rationale, reliability, and validity. J. Pers., 1961, 29, 344–349.
4. HESS, F. H. Attitude and pupil size. Scient. American, 1965, 212, 46–54.
5. HESS, F. H., & POLT, J. Pupil size as related to interest value of visual stimuli. Science, 1960, 349–350.