The image card was selected as a case study that demonstrates the importance of qualitative design tools for understanding and identifying user requirements in the inclusive design (ID) process. An experiment was conducted with 21 healthy male students (20-26 years old) in Kyushu University. Each student was asked two questions: How they felt about study room environment and how they hoped their study room to be in the future, if possible. Eleven students replied by using the image cards and the ten other students replied without using the cards. During the experiment, sensors were used to measure brainwave, heart rate and brain blood pressure. The intention was to gauge the effectiveness of the image cards on their brainwork and imagination. Based on the experiment, the following findings were identified between cards users and non card users: there were significant differences in the brain wave patterns and brain blood flow and there were no significant differences in the heart rate. This study proved that image cards are effective in interpreting user’s tacit thoughts and aspirations, helping designers create ID products and/or environments that meet their requirements. Furthermore, image cards stimulate users’ brain activities, helping determine their needs and problems easily and clearly.