Interrogative suggestibility, as measured with Gudjonsson Suggestibility Scales, consists of an individual’s tendency to yield to misleading questions (Yield) and to change answers after negative feedback (Shift). This study aimed to determine whether reinforced self-affirmation (RSA), a technique that aims to boost self-confidence in order to increase the tendency to rely on one’s own memory instead of external cues, can reduce interrogative suggestibility. RSA consists of self-affirmation induced by means of writing down one’s greatest achievements in life and of manipulated positive feedback. The efficacy of two kinds of positive feedback was explored. Shift was reduced by positive feedback relating both to memory and to the feeling that a person is very independent in their judgements, while only feedback related to memory reduced Yield. The results are discussed in terms of the different mechanisms underlying Yield and Shift. Inducing independence of judgements might not have been effective in the case of Yield because to some extent it taps opinions but not the quality of a cognitive process such as memory. An individual may believe in their own opinions and views but still be unsure about the quality of their own memory.