It is possible to study objectively the form of thinking that occurs covertly in many types of typical tasks and activities in everyday life through think aloud or talk aloud protocols (or protocol analysis) (Ericsson and Simon, 1980). One of the biggest obstacles in this type of study is to find nonreactive settings to reproduce the thinking process without altering how the subjects would normally think. The single most important precondition for successful direct expression of thinking is that the participants are allowed to maintain undisrupted focus on the completion of the presented tasks. They should not describe nor explain their thoughts to anyone during the process. Interviewers should also limit their interactions with the subjects as much as possible during the sessions. Subjects can also be given a series of simple warm-up exercises (such as mental multiplication of two numbers) that will provide them with the practice of directing their full attention to the presented task while verbalizing their thoughts.
If participants are asked to describe or explain their thinking, it is found that such verbalizations present "a genuine educational opportunity to make students' reasoning more coherent and reflective" (Ericsson and Simon, 1998). These subjects are more successful in mastering the material and generate more self-explanations and monitor their learning better. Writing is found to be the most effective (as well as demanding) activity to improve and develop student's thinking.
Ericsson, K.A. and Simon, H.A. (1980). Verbal Reports as Data. Psychological Review. 87(3), pp 215 - 251.
Ericsson, K.A. and Simon, H.A. (1998). How to Study Thinking in Everyday Life: Contrasting Think-Aloud Protocols with Descriptions and Explanations of Thinking. Mind, Culture, and Activity. 5(3), pp 178 - 186.