Making choices for oneself is known to enhance memory and improve motivation. However, little research has examined how self-choice influences cognitive processing, particularly the balance between cognitive stability (the ability to maintain relevant information) and cognitive flexibility (the ability to adapt to changing task demands). This study investigated whether linking a choice to the self would affect task switching and interference control. It was hypothesized that self-association would enhance attention to the selected stimulus, supporting its maintenance while making it more difficult to switch between task rules and regulate interference from features previously relevant or irrelevant.
Participants performed a parity judgment task in which digits were presented on two simultaneously displayed geometric shapes. The task included two block types: in the Perseverance block, the shape serving as the target in the initial phase became a distractor later, whereas in the Distraction block, a distractor shape became the new target. The target shape was determined under two conditions: in the simple-choice condition, participants selected a preferred shape; in the self-association condition, they selected a preferred shape and then underwent a procedure linking the shape to the self.
The results indicated that simply choosing a shape did not significantly affect performance. In contrast, in the self-association condition, response times were consistently slower when task roles changed. This suggests that self-association promoted persistence with the chosen stimulus, facilitating its maintenance but increasing the costs of both task switching and interference control.
These findings indicate that it is not choice itself that alters cognitive processing, but rather the link between the choice and the self. While self-association may increase the costs of switching and interference control, it also suggests that merely making a choice is insufficient and that meaningful effects on cognitive processing emerge only when choices are tied to the self.