In the 1960s, three approaches to the study of human motivation were dominant:

1. Drive Theory. Hull (1952), and others, asserted that motivation stemmed from physiological need deprivation which “drove” organisms to engage in random activity until, by chance, the need was satisfied and the drive was thus reduced. On subsequent occasions, cues in the situation would be recalled so that organisms would take suitable action rather than engage in random trial and error. This theory encountered numerous difficulties. For example, it was found that not all motivation stems from physiological needs (e.g., curiosity, self¬ efficacy). Second, not all need deprivation leads to an increase in drive (e.g., certain vitamin deficiencies). Third, partial need satisfaction sometimes leads to increased drive (e.g., as when the appetite is “whetted”). Finally, organisms, including people, often are motivated to engage in activities that increase rather than decrease tension (e.g., many purposeful human activities).