Neural systems of decision making are still not clear. A cognitive bias can provide clues to know them. Focusing on the normalcy bias, we investigate neural systems of valuation. Through the construction of new communication systems that can avoid the illogical influence of this normalcy bias, we will discuss neural systems of decision making and the way to distribute information accurately and understand it correctly.

The normalcy bias is a psychological reaction to the extraordinariness when we face a danger or a threat. In order to escape uncomfortable cognitive dissonance such as fear and anxiety, we underestimate the extraordinariness. It can be thought that the normalcy bias is one of homeostatic regulations to inhibit the excessive response of amygdala, which triggers risk-aversion actions by releasing neurotransmitter noradrenaline to cause fears and the terrors, because excess noradrenaline induces depression. On the other hand, in a time of disaster, the normalcy bias distorts the logical decision making and leads the delay of evacuation. How can we lead the evacuation without the invocation of the normalcy bias? We think that a cognitive bias of similar magnitude will cancel competitor's effect.

According to the prospect theory, if the expectation is equal, people evaluate the certainty to avoid risks of no gain in beneficial returns. In the loss recovery, they evaluate the possibility of freedom from loss accompanied by risks of no gain. Simulation results indicate that communication systems that appeal to neural circuits not for phobic avoidance but for gain and loss can inhibit the invocation of normalcy bias, if neural circuits of these cognitive biases are independent. A cognitive bias can provide findings to reveal neural mechanisms of valuation. Using appropriate tasks, further investigation on the switching of cognitive biases will contribute to the understanding of neural mechanisms of decision making and the development of new communication systems.