OFC in decision-making and emotion

     The orbitofrontal cortex (OFC) is perhaps one of the most understudied regions in the brain. Many functions of the orbitofrontal cortex are still unknown, but there is a growing push of research to better understand this part of the brain. The orbitofrontal cortex is believed to play a big role in decision-making as Dr. Kahnt et. al explain in their article “Neural circuits for inference-based decision-making”. Another prominent function of the OFC is its role in emotion, which Edmund Rolls et. al address in their research “The orbitofrontal cortex: reward, emotion, and depression”. This link between emotion and decision-making can give us an insight into why our decision-making skills are impacted so heavily by emotion, and vice versa.

    Thorsten Kahnt et. al take a deeper look at the brain regions and networks that are involved in inference-based decision-making and the role of the orbitofrontal cortex. Kahnt states, “ these findings suggest that the OFC is a critical hub in the brain networks that supports inference-based decision-making”, demonstrating the OFC’s essential role in decision-making. Kahnt looks at two scenarios of decision-making: decisions in novel situations, and decision-making when the outcome changes which requires inference. These types of tasks depend heavily on the use of learned associations, which occur in the orbitofrontal cortex. First, Kahnt examines learned associations between visual cues during a preconditioned phase. In this phase, participants associated cue A to cue B, and cue C to cue D. This was followed by the conditioned phase, where cue B presented an award while cue D did not. Subjects predicted that cue A would also yield a reward due to its association with cue B, showing that the subjects used novel inference to connect the two cues to the rewards. During fMRI recording, the OFC was active during the preconditioning phase, conditioned phase, and at the time of decision-making showing that the OFC is actively involved in these processes. The research continues to show decision-making when outcomes change. This aspect of the research requires one to use associations between cues and outcomes to infer the new value[KV1] , instead of flexibly using learned associations. Animals are given two cues and two associated rewards, intact animals tended to choose the cue associated with the reward that was not just consumed. A lesion in the OFC showed that the OFC is involved specifically in inferring novel values and using the new value in decision-making. Kahnt’s research shows just how involved the orbitofrontal cortex is in the decision-making process.    

    Frank on the other hand, look at the orbitofrontal cortex in regard to emotion in his study. He continuously references studies done to strengthen the hypothesis that the OFC is highly involved in emotion and emotional learning. Frank’s research shows that the OFC and amygdala have strong bidirectional connectivity.  Emotionally relevant stimuli are shown to activate parts of both the OFC and amygdala. One of the most interesting points the research brings up is how the “OFC supports visual processing during periods of visual uncertainty”, which directly correlates to the OFC’s role in decision-making like Kahnt mentions in his study. His research shows that the OFC exhibits strong signals when exposed to both pleasant and unpleasant stimuli. Frank’s research stresses how essential the orbitofrontal cortex is to emotion processing.                                

     These two studies help us gain a better understanding of the orbitofrontal cortex and its functions. This also provides insight into why our decision-making abilities are so heavily impacted by our emotions. Since these functions are being processed in similar brain regions it makes sense that they would have an impact on each other as the research suggests. Since orbitofrontal cortex research is still relatively new, there is still some work to be done to understand the full capacity of the region. It is also important to consider that a majority of brain processes occur on many levels, so even though the OFC plays a key role in both decision-making and emotion other areas take part as well that could contribute to how these functions are processed. It is intriguing to see where this area of research will go in the future.

 

References

Wang, F., & Kahnt, T. (2021). Neural circuits for inference-based decision-making. Current Opinion in Behavioral Sciences, 41, 10–14. https://doi.org/10.1016/j.cobeha.2021.02.004

Frank, D. W., Costa, V. D., Averbeck, B. B., & Sabatinelli, D. (2019). Directional interconnectivity of the human amygdala, fusiform gyrus, and orbitofrontal cortex in emotional scene perception. Journal of Neurophysiology, 122(4), 1530–1537. https://doi.org/10.1152/jn.00780.2018