There are some people who make decisions—such as choosing a car or an apartment to buy from a multitude of options—in a jiffy. And there are other people who spend agonizing hours and minutes trying to find the right shade of lipstick or what to order when eating out. What lies behind their indecisiveness?

Even the most indecisive people are rational, intelligent adults who function perfectly in their daily lives and do not falter when carrying out their duties and responsibilities. Yet, it seems that they cannot do much about their tendency to dilly-dally or make hasty decisions.

According to a recent study, the quality of the flow of information between the various regions of the brain indicates how decisive or indecisive a person is. When the flow of information is disrupted, people show indecisiveness. However, they do not waver on all types of decisions.

The link between indecisiveness and the brain

Scientists have long been curious about how human beings make decisions—from simple to the more complex ones—and why some people are more indecisive than others.

Scientists believe that the neural pathways that are involved in decision-making are also closely related to choice certainty.

According to them, the orbitofrontal and the cingulate cortices are involved in calculating rewards or conflict. It is known that living beings make decisions on the basis of the rewards or conflicts they expect as outcomes of their choices. So it is likely that the neural activity in these cortical regions could also be involved in decision certainty. These findings motivated scientists to explore what exactly happens in the brain during decision-making that can make a person indecisive.

In one experiment, two monkeys were made to perform a decision-making task that they had never attempted before and without external instructions. During this task, their brain activity was recorded and measured. Scientists discovered that the brain produced consistent neural activity—the transmission of signals from one region of the brain to another—when the monkeys made rapid decisions without wavering on them.

On the other hand, the neural activity seemed disrupted when the monkeys hesitated to make a clear choice. At other times when it seemed that the monkeys could not decide between the given options, the different processing regions of their brains fired up one after the other, as if they were weighing every option before deciding on one.

This experiment proved that contrary to popular notion, decision-making is affected not only by the relative strength of the various brain regions but also by the quality of information transmission between these regions. However, this finding was not tested on human beings until now.

Why are people indecisive?

During the recent experiment, scientists used a non-invasive brain stimulation method to activate the prefrontal and parietal cortices of the brains of the subjects. These areas of the brain are known to be involved in the decision-making process.

The subjects had to make both preferential and purely sensory-based decisions. The scientists discovered that indecisiveness increased when information flow was disrupted between the prefrontal and parietal cortices but only for preference-based decisions, like when the subjects had to figure out if they “liked” something more than the other. Purely sensorial decisions that had to be made on the basis of objective facts, like if one food item tasted better than the other, were unaffected by the quality of flow of information.

What affects decision-making and leads to indecisiveness?

The fact that the quality of the flow of information affects decision-making indicates that stimuli related to the decision are processed in different regions of the brain before they make their way to the decision-making centers.

An individual’s unique preferences for risk and ambiguity influences her decisions. The inherent risk or ambiguity in the choice options activates the posterior parietal cortex and the lateral prefrontal cortex of the brain respectively. So a person who has a preference for ambiguity sends stronger signals from the lateral prefrontal cortex that triggers a phase of deep analysis and prevents impulsive decision-making. It may be appear that this person is wavering before making a decision.

Scientists also believe that because the risk-reward system of the brain is closely related to the decision-making process, genetic variations in the dopamine-related genes can make a person more or less indecisive than another person. The unique expression of these genes may heighten or dampen the perception of risk or reward from choosing a particular course of action and thus, make a person quickly reach a decision or waver before making one.

Some scientists suggest a role of the hippocampus in making quick decisions or being indecisive. The hippocampus is involved in building long-term memories that influence learning and application. This part of the brain also assigns values to memories.

In an experiment, scientists created an association between earning monetary rewards and certain items in the memory that were previously not associated with money. Monetary reward is a powerful motivating factor for choosing one option over another. After this association was made, the subjects tended to quickly choose the non-rewarded items. The role of the hippocampus indicates that how fast the memories relate to rewards are activated influences the speed of a decision. However, scientists say that this correlation is true only for value-based decisions.

The implications of the above-mentioned findings

The above-mentioned findings have far-reaching implications in the treatment and/or rehabilitation of individuals who have suffered brain trauma and are exhibiting impulsive decision-making tendencies that might harm them or people near them.

By learning why and when people are indecisive, scientists can formulate genetic, pharmacological or therapeutic treatment methodologies that will enable these people to be less hasty and allow themselves time to make more prudent and well-judged decisions. However, more research needs to be carried out in this regard.

References

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