The Causal Role of the Left Angular Gyrus in Creativity-Driven Restructuring

Creative problem-solving relies on the flexible reorganization of prior knowledge to reshape complex memory structures, yet the behavioral and neural processes supporting this transformation remain poorly understood. The angular gyrus (AG) may play a key role in creativity-driven restructuring by integrating semantic information. To investigate this, participants underwent anodal transcranial direct current stimulation (tDCS) over the left AG or sham stimulation during a creative story generation task. Pre- and post-task semantic memory structures were assessed via free association and relatedness judgment tasks under electroencephalography (EEG). We found that creative ideation facilitated semantic memory restructuring–measured with increased network connectivity and decreased network compartmentalization, indicating a more integrated and flexible network, typically under anodal tDCS. At the neural level, creative ideation was associated with reduced N400 (lower semantic integration effort) and decreased neural representation similarity (greater flexibility) for unrelated story words, primarily observed in frontal regions under anodal tDCS. Moreover, these restructuring effects were specifically predicted by creative ideation and anodal tDCS. Critically, creative ideation functions not as a mediator of tDCS effects, but as a direct driver of restructuring. These findings highlight the unique role of creativity, particularly with anodal stimulation of the left AG, in driving knowledge restructuring.