Generative AI as a design stimulus in design cognition and its relationship to design creativity: a protocol study based on FBS coding

This study investigates generative AI as an external stimulus in apparel engineering design, focusing on how it enters design cognition and relates to design creativity. Protocol analysis was applied to a design task involving 20 participants, with 10 in each of the AI and traditional design groups. Data were analyzed using FBS coding, AI-intervention markers and expert ratings. Of 25 AI interaction events, 19 were followed by identifiable FBS activity after designers evaluated, adopted or modified AI output. Evaluation was most often followed by behavioral reasoning, whereas adoption and modification were most often by structural reasoning. AI intervention did not significantly alter F/B/S composition, transition distribution or transition time, and the groups did not differ significantly in overall creativity or its three dimensions. Across participants, however, relative F/B/S composition was associated with overall creativity, particularly the proportion of functional cognition relative to behavioral and structural cognition. Given the small sample, 30-min task and limited inter-rater agreement, these findings provide process-based evidence of how designers process AI-generated information, rather than causal evidence that AI consistently improves creativity or restructures design cognition.