Final answer:
The study by Rosenthal and Jacobson shows the 'self-fulfilling prophecy' concept, where teachers' belief in 'late bloomers' likely led to positive changes in those students' behaviors and IQ scores.
Step-by-step explanation:
The results from the study conducted by Robert Rosenthal and Lenore Jacobson (1968) demonstrate the concept of the self-fulfilling prophecy. This phenomenon occurs when a person's expectations about another individual influence that individual's behavior in such a way that the expected behavior is more likely to occur. In this case, teachers' beliefs about the potential of the so-called 'late bloomers' likely led them to give more positive attention and higher expectations to these students, which, in turn, positively affected the students' performance and IQ gains.