The method of introspection was used by titchener to identify

elements of sensory experience

Explanation:

Edward B. Titchener was one of the famous psychologists, he has started his work with Wilhelm Wundt. Titchner has elaborated the work of Wilhelm Wundt.

Titchener uses the introspection method to describe the different aspects or components of consciousness. Titchener kept several strict guidelines to report an introspective analysis and has referred to it as the stimulus error. He didn't abandon the introspective or the structuralist approach.

In the question above, the statement signifies the use of elements of sensory experience.