While reinforcement plays a role in the development and maintenance of MDD, it is not necessarily clear cut as it is in the development of anxiety disorders. It would not be as evident as driving on the freeway and becoming sad and then developing MDD. Several factors play a role in the development of MDD. For example, repeated exposure to stressful life events or aversive consequences with which they are unable to cope, may lead individuals to question their abilities and self-worth, leaving them with feelings of helplessness and hopelessness, which may eventually trigger a major depressive episode. Self-talk and behavioural deficits (lack of self-reward, inability to reward others) and excess (complaining, self-criticism) will then perpetuate the depressive episode (Bourne, 2005; Leahy & Holland, 2000).
While the development of anxiety and mood disorders may differ somewhat, from a cognitive behavioural perspective, the assumption is that we have reinforced specific self-talk, underlying assumptions, and core beliefs (about ourselves, about others, the world, and the future), as well as emotional and behavioral patterns which in combination, breed anxiety and mood disorders (Beck, 1976; Bourne, 2005; Burns, 1999; Leahy & Holland, 2000).
From a cognitive behavioral frame-work, treatment of anxiety or mood disorders will focus on challenging dysfunctional cognitive and behavioral processes and reinforcing healthier more adaptive ones (Beck, 1976; Bourne, 2005; Burns, 1999; Leahy & Holland, 2000). However, from a neuro-scientific standpoint it is suspected that a chemical imbalance of serotonergic and noradrenergic neurotransmitters plays a significant role in both anxiety depressive disorders. Research suggests that the use of medications such as SSRIs should re-stabilize these imbalances and reduce symptomology. Thus, while according to the Controlled Drugs and Substances Act (1999) only medical doctors, dentists and veterinarians are allowed to prescribe controlled substances, recommendation of medication is still considered as part of treatment plan for anxiety and mood disorders (Burns, 1999; Sadock & Sadock, 2007).