Sketching is widely used as a creative tool, playing a significant role in industrial design. Designers commonly use sketching to generate and evaluate ideas, leading to subsequent development of the most promising ideas. The current study examined the use of text in the idea generation sketching process among novices and experts. The electrophysiological correlates of thought processes were measured using electroencephalography (EEG). The thought process involved in idea generation was coded according to working memory components, and sketches were scored. The results revealed that experts generated better quality ideas, using similar thought processes. Importantly, the use of text increased the number of creative elements in ideas with lower creative quality among both novices and seniors. Electrophysiological analysis revealed that EEG signals corresponded with this behavioral pattern. Novices showed an activation pattern of low creativity, and the use of text activates the right hemisphere. Overall, the results revealed that the quality of concepts stored in memory was associated with a difference in quality between experts and novices, and that text elicited a higher volume of diverse analytical thinking that helped broaden creative possibilities rather than improving creative quality.