Stimulating Self-Regulation: A Review of Non-invasive Brain Stimulation Studies of Goal-Directed Behavior

Self-regulation enables individuals to guide their thoughts, feelings, and behaviors in a purposeful manner. Self-regulation is thus crucial for goal-directed behavior and contributes to many consequential outcomes in life including physical health, psychological well-being, ethical decision making, and strong interpersonal relationships. Neuroscientific research has revealed that the prefrontal cortex plays a central role in self-regulation, specifically by exerting top-down control over subcortical regions involved in reward (e.g., striatum) and emotion (e.g., amygdala). To orient readers, we first offer a methodological overview of tDCS and then review experiments using non-invasive brain stimulation techniques (especially transcranial direct current stimulation) to target prefrontal brain regions implicated in self-regulation. We focus on brain stimulation studies of self-regulatory behavior across three broad domains of response: persistence, delay behavior, and impulse control. We suggest that stimulating the prefrontal cortex promotes successful self-regulation by altering the balance in activity between the prefrontal cortex and subcortical regions involved in emotion and reward processing

A Multisite Preregistered Paradigmatic Test of the Ego-Depletion Effect

We conducted a preregistered multilaboratory project (k = 36; N = 3,531) to assess the size and robustness of ego-depletion effects using a novel replication method, termed the paradigmatic replication approach. Each laboratory implemented one of two procedures that was intended to manipulate self-control and tested performance on a subsequent measure of self-control. Confirmatory tests found a nonsignificant result (d = 0.06). Confirmatory Bayesian meta-analyses using an informed-prior hypothesis (δ = 0.30, SD = 0.15) found that the data were 4 times more likely under the null than the alternative hypothesis. Hence, preregistered analyses did not find evidence for a depletion effect. Exploratory analyses on the full sample (i.e., ignoring exclusion criteria) found a statistically significant effect (d = 0.08); Bayesian analyses showed that the data were about equally likely under the null and informed-prior hypotheses. Exploratory moderator tests suggested that the depletion effect was larger for participants who reported more fatigue but was not moderated by trait self-control, willpower beliefs, or action orientation.</p

Aftereffects of self-control on positive emotional reactivity

According to the process model of ego depletion, exercising self-control causes shifts in motivation and attention that may increase positive emotional reactivity. In an initial study and a preregistered replication, participants exercised self-control (or not) on a writing task before reporting their emotional responses to positive, negative, and neutral images. In Study 1 (N = 256) we found that exercising (versus not exercising) self-control increased positive emotional responses to positive images among more extraverted individuals. In Study 2 (N = 301) we found that exercising self-control increased positive reactivity independent of extraversion. These findings support the process model of ego depletion and suggest that exercising self-control may influence responding that does not entail self-control (i.e., positive emotional reactivity)—an outcome that is not anticipated by the limited resource model of self-control

Aftereffects of self-control on positive emotional reactivity

According to the process model of ego depletion, exercising self-control causes shifts in motivation and attention that may increase positive emotional reactivity. In an initial study and a preregistered replication, participants exercised self-control (or not) on a writing task before reporting their emotional responses to positive, negative, and neutral images. In Study 1 (N = 256) we found that exercising (versus not exercising) self-control increased positive emotional responses to positive images among more extraverted individuals. In Study 2 (N = 301) we found that exercising self-control increased positive reactivity independent of extraversion. These findings support the process model of ego depletion and suggest that exercising self-control may influence responding that does not entail self-control (i.e., positive emotional reactivity)—an outcome that is not anticipated by the limited resource model of self-control

Aftereffects of self-control: Emotional reactivity

Study examining the aftereffects of self-control on emotional reactivity, including the moderating effects of extraversion and neuroticism

Improving self-control by practicing logical reasoning

We tested the hypothesis that practicing logical reasoning can improve self-control. In an experimental training study (N = 49 undergraduates), for one week participants engaged in daily mental exercises with or without the requirement to practice logical reasoning. Participants in the logic group showed improvements in self-control, as revealed by anagram performance after a depleting self-control task. The benefits of the intervention were short-lived; participants in the two groups performed similarly just one week after the intervention had ended. We discuss the findings with respect to the strength model of self-control and consider possible benefits of regular cognitive challenges in education

Hypothesis and Analysis Plan: Replication

Hypothesis and analysis plan for replication of original stud

Analyses and Results: Original Study

Results from original study, along with SPSS syntax