Behaviors are occurring with the activity of neurons, the interaction between the brain’s output and impute systems. Some animals have bigger brains, so their behaviors and alternatives are more flexible. Having these kinds of flexibility is not always giving a pure advantage to an organism1. Having a large scale of information gathered from the outside world requires increased coordinative and decision-making functions. Due to this fact most animals, including humans, evolved to have some specific mechanisms in certain areas that provide the coordinated motor processes in our brain. The terms “frontal” and “precentral” were used by Brodmann to state the two main regions of the frontal lobe of primates2. He observed that in non-primate organisms, the frontal region is either not developed well or absent. He concluded that this frontal region might be unique for primates.

Cognitive control referred to the ability to adjust behavioral responses to produce behaviors with precise wisdom and aim3. Cognitive control can be divided into three main parts in the process4. Firstly, our long-term goals are maintained in our internal mental representation. Secondly, the interaction with the world and the interaction’s results are monitored. Lastly, the concluded behavior adjusted and fit our goals if possible. The prefrontal cortex is the front part of the frontal lobe in the brain and has an important effect on the functions of cognitive control. Such as working memory, rule-switching, and decision-making capabilities. The decision-making criteria work with a reward-based system. While making a decision, thinking about the possible outcomes with past experiences provides huge flexibility and comparison of the values as a reward5.
The dorsolateral prefrontal cortex (DLPFC) is an area found in the prefrontal cortex, and its function depends on several neuromodulatory molecules. Dopamine is the most critical molecule that affects the function of DLPFC6. If the dopamine level changes, such as blocking the dopamine in the cortex, creates difficulty in performing the tasks in DLPFC. For instance, Parkinson’s disease and schizophrenia are known for arising with the dysfunction of the prefrontal cortex7. Due to dopamine modulating the electrical activity of neurons in that area, patients that have these disorders had increased performance on working memory tests when their dopamine levels become optimal with treatments. The reward-based system is also affected by dopamine and its quantity. In the process, when the events with certain rewards are linked with predictors, dopaminergic neuron activity is increased. Interestingly, this increase only occurs during the expectation process, not in the reward period8. So, it is easy to conclude that comparing our goals with rewards might not be efficient when the dopamine level in the system is not normal.

The processing route of dopamine can be classified into three ways, sensory input, memorization and manipulation, and motor output3. The prefrontal cortex receives input from different areas of the brain, including both subcortical and higher sensory areas, and reflects other several areas. In the reflection part, the sensory information is gated in the prefrontal cortex, which maintains the information and transfers it to target areas with motor commands. Due to circumstances, there might be several different response options, even though the source of input is the same. There is a great example of the prefrontal cortex’s working mechanism3. When a phone is ringing, the phone’s sound is recognized first. We tend to act as answering the phone with maintaining the sound in the working memory. The working memory represents the environment that you are in when the phone is ringing. When you recognize the sound of the phone in your home, you will fulfill your tendency and answer it. Yet, if you are in someone’s house during the recognition process, you do not act in the same way. These kinds of situations create multiple types of responses, and they must be stabilized in a complex system to act in the best way.
To sum up, many different models are currently being used to understand and find new results and relations in this area. It is clear to see that the prefrontal cortex plays a huge role in the evolution of primates and the creation of unique interaction patterns in the brain. It affects our way of the act on certain events and understanding the mechanism behind our behaviors carries huge importance. The main players in these patterns, such as dopamine, are the most significant preference to study to reduce this complexity to conclude. By no means, the things that will be discovered will give us genuine insight into the understanding of human nature.
References:
- Miller EK, Cohen JD. An integrate theory of PFC function. Annu Rev Neurosci. 2001;24:167-202. www.annualreviews.org
- Carlén M. What constitutes the prefrontal cortex? Science (80- ). 2017;358(6362):478-482. doi:10.1126/science.aan8868
- Ott T, Nieder A. Dopamine and Cognitive Control in Prefrontal Cortex. Trends Cogn Sci. 2019;23(3):213-234. doi:10.1016/j.tics.2018.12.006
- Widge AS, Heilbronner SR, Hayden BY. Prefrontal cortex and cognitive control: New insights from human electrophysiology [version 1; peer review: 3 approved]. F1000Research. 2019;8:1-10. doi:10.12688/f1000research.20044.1
- Chaua BKH, Jarvisc H, Lawa CK, Chongc TJ. Dopamine and reward: A view from the prefrontal cortex. Behav Pharmacol. 2018;29(7):569-583. doi:10.1097/FBP.0000000000000424
- Diamond A, Briand L, Fossella J, Gehlbach L. Genetic and Neurochemical Modulation of Prefrontal Cognitive Functions in Children. Am J Psychiatry. 2004;161(1):125-132. doi:10.1176/appi.ajp.161.1.125
- Williams G V., Goldman-Rakic PS. Modulation of memory fields by dopamine D1 receptors in prefrontal cortex. Nature. 1995;376(6541):572-575. doi:10.1038/376572a0
- Huang S, Borgland SL, Zamponi GW. Dopaminergic modulation of pain signals in the medial prefrontal cortex: Challenges and perspectives. Neurosci Lett. 2019;702(November 2018):71-76. doi:10.1016/j.neulet.2018.11.043
Figure References:
- Carlén M. What constitutes the prefrontal cortex? Science (80- ). 2017;358(6362):478-482. doi:10.1126/science.aan8868
- Ott T, Nieder A. Dopamine and Cognitive Control in Prefrontal Cortex. Trends Cogn Sci. 2019;23(3):213-234. doi:10.1016/j.tics.2018.12.006
Inspector: Süleyman ŞAHİN