Operationalizing the Dynamic Framework of Thought: Cognitive Constraints Reveal Individual Differences in the Stream of Thought

Attention-Deficit / Hyperactivity Disorder (ADHD) is known to be associated with racing thoughts. Recent theoretical work suggests that thought dynamics could be modulated by cognitive constraints. In the present project, we operationalized the unfolding of spontaneous thoughts with a word generation paradigm. We contrasted two levels of associative constraints on word generation, and we tested the differential impact of ADHD traits on the dynamics of the resulting “trains of thoughts”. In the strong constraint condition, each word had to be semantically close to the previous one; in the weak constraint condition, participants had to say the words that spontaneously came to their mind.We first validate the notion that the weak constraint condition mirrors free thought by comparing the word produced in the task with participants’ self-reported real-life thoughts. Using response times and semantic metrics, we then show that participants with higher ADHD traits produced more dynamic series of words, but only in the weak constraint condition mirroring free thoughts. Our study supports the idea that ADHD symptoms in the general population are associated with heightened thought volatility, and provides one of the first operationalization of the notion of cognitive constraints in spontaneous thought research.