A study conducted by Lucas et al. displayed that when the maths problems became increasingly more difficult, the rate of conformity also increased. This is because the participants knew ‘their own mind’, so when the problems were easy they did not have to rely on the group. However, once they became harder the participants looked onto the group for answers, due to the fear of failure and getting the answers wrong. This shows that ISI is an adequate and valid explanation for conformity because the results are what ISI predicted.