He constructed an experiment whereby all confederates verbalized their responses aloud and only the real participant was allowed to respond in writing.
The first method, called the "think-aloud" method, encourages participants participating in the interview to verbalize their thoughts while responding to the survey questions.
If the patient has a speech or language impairment that prevents them from verbalizing an answer, the answer can be selected from a series of images shown to them.
Undoubtedly, cognitive studies provided a lot of evidence supporting the idea that individuals can listen, verbalize, or manipulate, and rescue information in multiple task condition.