The hidden bias behind chronic indecision

Humans are required to make several decisions daily, from choosing what to eat at a restaurant to more crucial choices, such as the studies they wish to complete.

Behavioral scientists and psychologists have been trying to understand how humans make decisions for decades and have unveiled several biases, systematic and unconscious “traps” that prompt them to make poor decisions.

One difficulty that some people experience when trying to make decisions is indecisiveness. This inability to decide how to act in specific situations or what to choose among available options is common, yet in some cases it can become chronic and debilitating.

For instance, extreme indecisiveness is often experienced by people diagnosed with obsessive-compulsive disorder (OCD). OCD is a psychiatric disorder marked by recurring intrusive thoughts (i.e., obsessions) and repetitive behaviors (i.e., compulsions).

Researchers at University College London and other institutes recently identified a “mental trap” known as an information integration bias that could contribute to indecisiveness in individuals diagnosed with OCD and others who often find it hard to make decisions. Their paper, published in Nature Human Behavior, could inform future efforts aimed at improving people’s ability to make decisions.

“Biases in information gathering are common in the general population and reach pathological extremes in paralyzing indecisiveness, as in OCD,” wrote Magdalena del Rio, Nadescha Trudel and their colleagues in their paper. “We adopt a new perspective on information gathering and demonstrate an information integration bias whereby there is over-weighting of most recent information via evidence strength updates (ΔES).”

Exploring indecision across the obsessive-compulsive spectrum

To explore the mental processes linked to indecisiveness, del Rio and her colleagues recruited 5,237 individuals and asked them to complete an online decision-making task. This task entailed choosing which of two objects was more plentiful across 25 different locations. Notably, the participants could sample as many of the locations as they wanted before making their decision.

The researchers looked at how strongly participants updated their beliefs after they were granted access to new information. Their analyses focused on both the participants’ indecisiveness and a measure called ΔES, which indicates a change in the strength of available evidence.

“In a crowd-sourced sample, we find that a reduced ΔES weighting drives indecisiveness along an obsessive–compulsive spectrum,” wrote the authors. “We replicate this attenuated ΔES weighting in a second lab-based study (N = 105) that includes a transdiagnostic obsessive–compulsive spectrum encompassing OCD and generalized anxiety patients.”

The team’s laboratory experiments involving people diagnosed with OCD, generalized anxiety disorder, or no mental health disorders appeared to confirm the findings of their online study. Specifically, they showed that people who are more indecisive do not “adjust” their beliefs in response to new evidence as quickly and effectively as less indecisive people.

This “mental trap” would explain why some indecisive people continue seeking new information instead of making a decision. Interestingly, the researchers found that people diagnosed with both OCD and generalized anxiety tended to be swayed by this bias.

As part of their laboratory experiment, del Rio and her colleagues also recorded the brain activity of participants as they were completing the decision-making task. This allowed them to pinpoint brain signals that were linked to the updating of evidence after receiving new information, while also uncovering brain activity patterns that differed in highly indecisive people diagnosed with OCD or generalized anxiety.

“Using magnetoencephalography (MEG), we trace ΔES signals to a late neural signal peaking at ~920 ms,” wrote del Rio, Trudel and their colleagues.

“Critically, highly obsessive–compulsive participants, across diagnoses, show an attenuated neural ΔES signal in mediofrontal areas, while other decision-relevant processes remain intact. Our findings establish biased information weighting as a driver of information gathering, where attenuated ΔES is linked to indecisiveness across an obsessive–compulsive spectrum.”

New insight into the processes influencing human decisions

The results gathered by this team of researchers led to the identification of a bias that appears to impair people’s ability to integrate information before making decisions. They also uncovered brain regions that appear to be less active in individuals who are prone to this bias while they are processing information that could inform their decisions.

This recent study could soon pave the way for further research exploring the newly uncovered bias in people diagnosed with OCD, other psychiatric conditions or people with no known psychiatric disorders. In the future, this could pave the way for the introduction of new psychotherapeutic strategies designed to mitigate indecisiveness or support people who are struggling to make important decisions.

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