Cocaine Decision Making Process

1. Background
People make countless decisions every day, and the consequences of these choices significantly affect our physical, mental, social, and economic well being [21, 25]. Although the decision making process seems like an effortless task as it can be done unconsciously, we should appreciate the true complexity of the whole process. A high level of cognitive processes, as well as the evaluation of the outcome including the comparison between the expectation, and the consequences is mandatory every time when a decision is to be made [25, 29]. The functioning of this decision making process can be disrupted by numerous reasons, and chronic cocaine use is one of them. Cocaine not only causes impairment in the brain regions that are responsible
First of all, the dopaminergic neurons within the ventral tegmental area (VTA) will project into the brain reward center, consisting the nucleus accumbens (NAc) [26, 29], ventral striatum (vStr) [25, 28], amygdala [25, 28-29], medio-dorsal thalamus [26, 28]. Orbitofrontal cortex (OFC) [25-27], bilateral anterior insula [25-26, 28], hippocampus [29], anterior and posterior cingulated cortex (ACC and PCC) [25-26], ventral pallidum [29] as well as various cognitive control regions in the inferior parietal lobule and medial prefrontal cortex (mPFC) [25-26, 28]. As there is only limited understanding in the function of striatum, a brain region which is situated within the NAc [29], it is only natural to investigate its role in regulating the reward-related decision making
The vStr generally take effect in the evaluation, anticipation and consumption of the potential reward related to each action [20], especially when the rewards occurred unexpectedly, or unpredictable [21]. The vStr activity which is usually engaged before the decision is made [20] is intrinsically correlated with the measurement of the difference between received and expected rewards, in order to predict the future outcome [28]. These predictions are then used to determine the behaviour that is likely to achieve the higher offer of rewards in return [21]. Although it remains unclear whether activation in the vStr can be consistently associated with the representation of reward magnitude during both the reward expectancy and its consumption [21]. The vStr still plays a remarkable role in the complex decision making process, especially when the subject is under the influence of