I truly enjoyed reading Doug Sellman's paper [1]. These types of paper, which summarize the literature briefly and, even more importantly, review it critically, are needed, especially right now, as there are increasing numbers of scientific outlets for papers and it becomes increasingly difficult to gain an overview of the field—not only for young scholars, who have just entered the field, but also for ‘old and wise’ researchers who have been in the field for a long time. The paper is an eye-opener, not so much because of the discussed empirical evidence for the 10 important insights, but through the combination and order of the 10 things. It makes one think about where we stand and what the next endeavours should be.

However, the question is not whether or not I agree with Sellman on the selection of 10 most important ‘things’. Such a list is driven by personal experience, expertise and motivations. In fact, I fully agree with many of his statements; for instance, the neuropsychological processes related to addictive behaviours such as cue-signalling and reactivity, that go outside conscious awareness, the recent trends in thinking about addiction as complex gene–environment interactions and the statement that addictive behaviours occur mainly with other psychiatric disorders—which has huge complications for studying treatment effects. I also agree with the relevance of scrutinizing treatment alliances, and the dynamic developmental interactions between therapist and patient, rather than testing differences exclusively between treatments.

None the less, I question whether it is possible to make a list such as this that encompasses all addictive behaviours. I do not think so. The differences in prevalence, development, aetiology, neurological effects, physical and social consequences and cultural meanings in addictive behaviours are so profound that I do not believe it to be possible.

One of my main research areas is adolescent smoking. Compared to alcohol—one of the behaviours Sellman often refers to explicitly—the developmental trajectory for smoking is profoundly different. For example, people can show symptoms of nicotine dependence even after using cigarettes for a short period of weeks [2,3]. Because people in most countries start smoking at an early age, full-blown dependence—with all its accompanied symptoms such as withdrawal and craving—can be achieved in adolescence. The teenage years consist of a developmental period of life, which due to its specific social, individual, biological and neuropsychological features cannot be compared easily to other phases such as young adulthood or middle age. I will give a few examples: first, some brain areas are still in development affecting how smoking teens deal with decision making and impulse control [4] as well as craving [5], making it complex to devise effective treatments. Further, lapses and relapse in adolescents who want to quit smoking seem to be affected strongly by peer smoking and pressures to smoke, as well as by tempting situations such as going out and drinking alcohol [Van Zundert R., Shiffman S., Ferguson S., Engels R.C.M.E., unpublished data, 6]. The lack of experiences youths have with resisting temptations and cues make it difficult for them to control their impulses, as well as to foresee when and how these circumstances will occur [Van Zundert R., Shiffman S., Ferguson S., Engels R.C.M.E., unpublished data]. Secondly, identity formation processes shape how adolescents deal with the impact of the media, which leads to tobacco marketing and smoking portrayals in movies having a strong impact on young people's smoking initiation and continuation [7–10]. Thirdly, for adolescents who are in peer networks in which smoking is accepted, or even the norm, the social consequences are not negative and in many cases even positive, strengthening the habit. These processes are probably even stronger when adolescents grow up in families where parents and siblings are smoking [11].

Variations in courses, causes and consequences of addictive behaviours affect not only how people interpret and evaluate them morally, but also how we should treat them. The specific group I refer to, adolescents, means there is a need to develop a different approach for treatment of nicotine dependence than that of, e.g. alcoholism in adults, with a stronger focus on availability and social environmental interventions, combined with an individual approach such as working on realistic perceptions of one's self-efficacy (which are not formed well in adolescence as they hardly have experience with quitting smoking, or resisting temptations in general) and at the same time dealing with nicotine dependence symptoms [12–14].

I think that the more we know about addictions, the more we emphasize the differences between them. Therefore, I would encourage Sellman to come up with 10 lists of 10 important things.

Declaration of interest