另一方面，心理动力学方法主张在塑造人格和行为上的内在过程和童年经历，而不是行为主义和社会学习理论所确认的环境(Santrock 2005)。佛洛伊德假设所有的人类行为都是由满足基本驱动力的需求驱动的，并且这些驱动力会随着时间的推移而改变(Glassman 2000)。“作为满足焦点的物体会改变，满足的方式也会改变——即身体的某个部位是满足的中心”(格拉斯曼，第214页)。佛洛伊德性心理发展模型的一个观点认为，人一生中会经历五个发展阶段，但童年时期出现的前四个阶段会对人格产生影响(Glassman 2000)。这些阶段相对来说被称为口腔期、肛门期、性期、阴茎期、潜伏期和生殖期。例如，在理解吸烟是如何受到童年经历的影响时，有必要解释性心理发展的第一阶段。在发展的第一阶段，也就是人们所说的“口唇期”，西格蒙德·弗洛伊德认为，满足感主要集中在嘴巴上。因此，他明确指出，在这个阶段，如果六个月大的哺乳期婴儿在性欲期的任何一个阶段食欲不佳，焦虑会在成年期转变为一种精神健康障碍，称为神经症。因此，婴儿期的口腔固着表现为对口腔刺激的痴迷。这种口腔固着可以表现为对口腔满足的需要，比如吸烟。虽然性心理发展是理解吸烟行为的一个有效模型，但它缺乏生态有效性，因为在那里，延长母乳喂养可能不会导致一个人在成年后期采取成瘾行为，这是没有科学依据的。
On the other hand, the psychodynamic approach advocates on internal processes and childhood experiences in shaping personality and thereby behaviour rather than the environment as the behaviourism and social learning theory confirm (Santrock 2005). Freud assumed that all human action is motivated by the need to satisfy basic drives and that these drives change overtime (Glassman 2000). “The objects which are the focus of gratification change, and so the does the mode of gratification -that is the area of the body which is the centre of for gratification” (Glassman, p. 214). An aspect of Freud’s psychosexual model of development contended that there are five developmental stages that occur throughout life, but the first four that appears in childhood can have an effect on personality (Glassman 2000). These stages are relatively known as the oral, anal, sexual, phallic, latency and genital stages. For instance, in terms of understanding how smoking is influenced by experience in childhood, it is thus necessary to explain the first stage of psychosexual development. During the first stage of development known as oral stage, Sigmund Freud uttered that focus of gratification is mainly on the mouth. Therefore, he specified that during this stage if a six-month nursing baby ‘s appetite was dissatisfied at any point of the libidinal stage, anxiety would transform into a mental health disorder known as neurosis in adulthood. Therefore, an infantile oral fixation would manifest as an obsession of oral stimulation. This oral fixation can manifest itself as a need for oral gratification such as smoking. Though the psychosexual development is an effective model of understanding smoking behaviour however it lacks ecological validity as there it cannot be scientifically justified that prolonged breastfeeding might not lead to an individual adopting addictive behaviour in later adulthood.