A study of intentional inhibition of food stimuli among female restricted eaters

Do You Control Your Unconscious Action Impulses?

A crucial aspect of self-control is the voluntary inhibition of impulsive actions. Stimuli can elicit impulses (or preparation) to act not only in the presence but also in the absence of perceptual awareness, but whether people control action impulses elicited by unconscious stimuli remains unclear. This study used a masked prime version of the Go/NoGo/Free task and combined mathematical modeling of behavioral data to investigate whether people control the unconscious action impulses. In the experiment, when the subliminal prime stimulus triggers the unconscious action impulse, participants need to freely decide whether or not to perform the action. The results showed that the no-response rate was higher in Go-prime free-choice trials than in NoGo-prime free-choice trials, and there were marginally larger negative drift rates in the former than in the latter. The results suggest that people are more likely to make inhibitory decisions about unconscious action impulses. This finding provides support for a framework that extends the feedback loop model of intentional inhibition.

Behavioral impulse and time pressure jointly influence intentional inhibition: evidence from the Free Two-Choice Oddball task

Intentional inhibition is a crucial component of self-regulation, yet it is under-researched, because it is difficult to study without external stimuli or overt behaviors. Although Free-Choice tasks have been developed, it remains unclear how two key design features (i.e., behavioral impulse and time pressure) affect their sensitivity to intentional inhibition. To investigate this, the present study developed a Free Two-Choice Oddball task, which generated both an inhibition rate index and a response time (RT) index. Two experiments were conducted to systematically manipulate the ratio of the reactive standard to oddball trials and reaction time limit, inducing diverse behavioral impulses and different time pressures. The following findings were obtained from the critical Free-Choice trials. In the equal ratio condition, participants demonstrated comparable RTs for both the standard and oddball responses. In the moderate-ratio condition, participants exhibited longer RTs for the oddball than standard responses under low- but not high-time pressure. In the high-ratio condition, while RTs for the oddball responses were longer than those for the standard responses under both the high- and low-time pressures, participants displayed a decreased inhibition rate under the high-time pressure compared to the low-time pressure. Finally, participants exhibited a reduced inhibition rate in the high-ratio condition compared to the moderate-ratio condition. Together, these findings suggest that Free-Choice tasks can reflect intentional inhibition under specific conditions, and intentional inhibition is susceptible to both behavioral impulse and time pressure, while also establishing the theoretical and methodological foundations for subsequent research.