Impulse control is one of core abilities of the fully developed human brain. Lack of this control in adulthood is linked to a range of mental health concerns, including attention-deficit hyperactivity disorder (ADHD), personality disorders, certain forms of bipolar disorder and diagnosable problems with substance abuse\/substance addiction. In a study scheduled for publication in 2014 in the journal Drug and Alcohol Dependence, a team of Australian researchers used a large-scale analysis of previous study results to determine which forms of addiction are most clearly associated with impulse control problems. In addition to substance addiction, the researchers looked at two forms of non-substance-based behavioral addiction: gambling disorder and Internet addiction. Substance Addiction and Behavioral Addiction Most adults are aware of the existence of substance addiction. People affected by this problem have used a mind-altering substance long enough and often enough to inadvertently trigger lasting chemical change in the pleasure center, a part of the brain that provides much of the \u201cdesirable\u201d impact of substance use\/abuse. The change in question essentially causes the brain to expect the continued intake of a given substance; when the expected intake does not occur, an addicted individual experiences an unpleasant withdrawal syndrome that encourages a rapid return to substance intake. In addition to withdrawal symptoms, common indications of a substance addiction include an inability to set and maintain limits on substance use, rising tolerance to the effects of a given substance and a damaging pattern of daily behavior oriented around substance acquisition and substance use. People affected by behavioral addiction experience problems that are closely analogous to the symptoms of substance addiction, including lasting changes in brain function, an inability to set limits on participation in the behavior in question and the onset of a withdrawal syndrome when access to the behavior in question is unavailable. The American Psychiatric Association only began to officially acknowledge the existence of behavioral addiction in 2013. However, evidence for the existence of addictive relationships to certain pleasurable activities - including having sex, gambling, eating and using the Internet\u2014has been accumulating for some time. Impulse Control Impulse control naturally develops gradually as humans pass through childhood and adolescence and enter early adulthood. It belongs to a larger group of critical, higher-level mental skills known together as executive function. Psychologists and psychiatrists sometimes use the term behavioral inhibitory control to refer to the ability to restrain your impulses, consider your actions in advance and reject behaviors that are likely to cause you harm or otherwise produce undesirable outcomes. Adults who lack fully developed forms of this control have a greater tendency to act spontaneously, act recklessly and fail to use past experience as a guide for future behavior. Which Forms of Addiction In the study scheduled for publication in Drug and Alcohol Dependence, researchers from Australia\u2019s National Drug and Alcohol Research Centre re-analyzed the results of 97 previous studies that explored the connection between deficient impulse control and addiction. All of the studies under consideration compared groups of substance abusers and people affected by substance addiction or behavioral addiction to groups of people unaffected by diagnosable substance problems or behavioral addiction. Each of the studies used one of two well-established protocols for measuring the relative ability to control impulsive actions. After completing their analysis, the researchers identified several forms of addiction that clearly involve some sort of impulse control deficit, including alcoholism, cocaine addiction, tobacco\/nicotine addiction, methamphetamine addiction, MDMA (Ecstasy, Molly) addiction and gambling disorder. The same deficits in behavioral control appeared to one degree or another in non-addicted heavy users of alcohol, cocaine, tobacco\/nicotine, methamphetamine and MDMA. However, the researchers also concluded that impulse control deficiencies are not clearly linked to heavy use of or addiction to two other groups of substances: cannabis-based drugs (marijuana, hashish or hashish oil) and opioid drugs and medications. In addition, they concluded that some of the reviewed studies supported the role of impulse control problems in Internet addiction, while others did not. The study\u2019s authors note that, overall, their findings reinforce the strong link between diagnosable substance problems and poor impulse control in adulthood. Their findings also identify a link between impulse control problems and at least some forms of behavioral addiction. The authors believe that the absence of a connection between certain forms of substance addiction and impulse control deficiencies may have a significant impact on the ways in which treatment programs can best help their clients\/patients.