Most of us have experienced a moment when we couldn’t quite recall a word in another language: the idea is there in our minds, but we simply can’t find the expression for it. The research, published in Bilingualism: Language and Cognition, is part of Dr. Gyulten Hyusein’s PhD dissertation research at the Language and Cognition Laboratory in the Department of Psychology at Koç University, conducted in collaboration with Prof. Dr. Tilbe Göksun. It explores a question with clear everyday relevance: When bilingual individuals switch to their second language, does their creativity decline?

To find out, researchers asked Turkish-English bilingual university students to complete two classic creativity tests, one in Turkish (their native language) and one in English (their second language). The first test, the Alternative Uses Task, asked participants to come up with as many unusual uses for everyday objects as possible. This measured divergent thinking, the ability to generate many original ideas. The second test, the Remote Associates Test, presented three seemingly unrelated words and asked participants to find a single word connecting them all, measuring convergent thinking, the ability to zero in on a correct solution.

The results were clear-cut: Participants were more creative in Turkish across the board. They generated more ideas, came up with more original responses, and were better at finding the connecting word. But the researchers wanted to understand why. And this is where the study gets particularly interesting.

One key factor turned out to be mental imagery. After each task, participants rated how vividly they had been picturing things in their minds while working through the problems. Those mental images were richer and clearer in Turkish than in English. And the vividness of the mental images was strongly linked to better divergent thinking performance, regardless of which language was being used. In other words, the more vividly you can picture something, the more creative you tend to be. And, your native language seems to help you picture things more vividly.

The study also looked at hand gestures, the spontaneous movements we tend to make while we speak. Gesturing while talking in Turkish was gently linked to better creative idea generation, while gesturing in English was associated with worse performance. One explanation is that in a second language, people may use their hands to compensate for what they cannot easily say, but the gestures end up substituting for ideas rather than generating them. For convergent thinking, more gesturing combined with vivid imagery actually predicted lower scores in both languages, suggesting that rich visual thinking might sometimes get in the way of homing in on a single correct answer.

Perhaps the most surprising finding was that English proficiency, how well participants rated their own command of English, did not translate into richer mental imagery in English, nor did it explain the creativity gap on its own. This suggests that creativity in a second language is not simply a matter of how fluent you are. Something deeper, connected to the emotional and sensory richness that our native language carries, seems to matter as well.

For the millions of people who work, study, and collaborate in a language that is not their first, these findings raise important practical questions. They suggest that the language we think in is not just a passive vehicle for expressing ideas: It actively shapes the very texture of those ideas.