Delayed gratification, or deferred gratification, is the ability to resist the temptation for an immediate reward and wait for a later reward. Generally, delayed gratification is associated with resisting a smaller but more immediate reward in order to receive a larger or more enduring reward later. A growing body of literature has linked the ability to delay gratification to a host of other positive outcomes, including academic success, physical health, psychological health, and social competence. Walter Mischel has led the research on delayed gratification, most notably the Stanford marshmallow experiment, which shed light on the long-term results of a person’s ability to delay gratification. A person’s ability to delay gratification relates to other similar skills such as patience, impulse control, self-control and willpower, all of which are involved in self-regulation. Broadly, self-regulation encompasses a person’s capacity to adapt the self as necessary to meet demands of the environment. Delaying gratification is the reverse of delay discounting, which is “the preference for smaller immediate rewards over larger but delayed rewards” and refers to the “fact that the subjective value of reward decreases with increasing delay to its receipt.” It is theorized that the ability to delay rewards is under the control of the cognitive-affective personality system (CAPS). Several factors can affect a person’s ability to delay gratification. Cognitive strategies, such as the use of distracting or “cool” thoughts, can increase delay ability, as can neurological factors, such as strength of connections in the frontal-striatal pathway. Behavioral researchers have focused on the contingencies that govern choices to delay reinforcement, and have studied how to manipulate those contingencies in order to lengthen delay. Age plays a role too; children under 5 years old demonstrate a marked lack of delayed gratification ability and most commonly seek immediate gratification. A very small difference between males and females suggest that females may be better at delaying rewards. The ability to wait or seek immediate reinforcement is related to avoidance-related behaviors such as procrastination, and to other clinical diagnoses such as anxiety, attention deficit hyperactivity disorder and depression. Sigmund Freud, the father of psychoanalytic theory, discussed the ego’s role in balancing the immediate pleasure-driven desires of the id with the morality-driven choices of the superego. Funder and Block expanded psychoanalytic research on the topic, and found that impulsivity, or a lack of ego-control, has a stronger effect on one’s ability to delay rewards if a reward is more desirable. Finally, environmental and social factors play a role; for example, delay is affected by the self-imposed or external nature of a reward contingency, by the degree of task engagement required during the delay, by early mother-child relationship characteristics, by a person’s previous experiences with unreliable promises of rewards (e.g., in poverty), and by contemporary sociocultural expectations and paradigms. Research on animals comprises another body of literature describing delayed gratification characteristics that are not as easily tested in human samples, such as ecological factors affecting the skill.