The Two Brain Networks That Influence Our Decision Making

Posted on February 7, 2017

Researchers have studied for decades the balance between speed and accuracy in decision making. It's a fundamental trade-off. Our brains try to produce the fastest bits of information as possible. Yet at the same time, we want the most relevant and accurate information. This requires time for processing and analyzing, which contrasts against our innate habit to produce a quick response. Thus, a juggle between speed and accuracy occurs, where previous research suggests that the subthalamic nucleus region of the brain has a key role in this process.

Peter Brown, a professor at the University of Oxford, explains that studies have been trying to measure the exact location and timing of neural activity in the brain to find out how exactly our minds balance the two out. Brown and his team found that easy tasks result in faster decision-making whereas difficult tasks take longer time. This suggests that harder assignments causes a delay in response as the brain needs more time to accumulate enough necessary information to make a decision. In other words, there is a threshold.

This threshold occurs at different levels depending on the type of task given. Brown and his team found that when participants were to focus on speed, the threshold level decreased significantly than when participants were asked to focus on accuracy, resulting in much faster response times. To pinpoint the exact location in the brain that was responsible for these processes, electrical activity of nerve cells in the subthalamic nucleus was measured. There, Brown and his team discovered two distinct neural networks. Each differ in the way that they respond to tasks.

The first network increases the criteria for the amount of information needed before making a decision, which is thus more likely to be activated when the focus is on accuracy. The second network decreases the threshold of information when a decision needs to be made quickly. These findings also suggests that the prefrontal cortext region of the brain is a key player in decision making.


Source material from Scientific American