The major objective of this series of studies was to clarify the concept of mastery motivation and to develop measures of this concept applicable to 1-year-old children. Three studies were made with 44 infants, aged 12 to 13 months. The first study, "Aspects of Mastery Motivation and Cognitive Functioning," utilized structured situations…

Tests of conditionability in infants were used in a longidudinal study of 32 subjects in the first year of life. The research was based on Eysenck's hypothesis that conditionability i s a unitary factor related to introversion-extroversion and attention span. The objective of the investigators was to devise a battery of conditioning tasks…