In adapting to our environment, we'd ideally use the results of previous actions to inform future choices, updating our expectations and decisions to reflect knowledge gained from earlier experiences. However, sometimes we ignore the past's feedback when we really should pay attention it, leaving us trapped in a series of bad decisions. A study published in PNAS demonstrates that this “bad choice persistence” occurs when changing our decisions would go against our existing biases. This means that our beliefs can trap us in a difficult-to-break bad-decision feedback loop.

To examine this phenomenon, researchers looked at how subjects integrated new experiences with their past history when completing a sensory stimulus task. The participants were asked to predict whether a visual stimulus would appear on the left side or the right side of a screen based on where the stimulus appeared in previous trials.

In the first set of experimental trials, the location of the stimulus was randomized. These trials assessed the subjects’ baseline biases towards choosing one side of the screen or the other. After establishing these biases, the participants began a second set of experimental trials. In these experiments, the stimulus' location was determined by a probabilistic model that set the odds of its location using both the participants' previous choice history and the item's previous locations.

During this set, researchers assessed subjects’ ability to change their predictions of where the stimulus would appear, taking into account their known biases and the where the stimulus had appeared in previous trials.

The researchers analyzed the data from these trials using a probabilistic choice model and a statistical test for the role of choice history in terms of predicting future choices. These analyses found that choice history and pre-existing bias both had a considerable effect on decision making. The effect of bias was strong and persisted across three different countries: the US, the UK, and Japan.

Education had a significant effect on choice biases. Participants with a PhD were more likely to switch their prediction if a previous one was incorrect; those without one were more likely to stay with the same choice. Both groups of subjects, however, exhibited irrational history-based biases, so education doesn’t fully explain the strong effect of existing biases.

You might expect that existing biases would diminish as participants completed more trials. Yet even as they became more experienced with the prediction task, biases remained a strong influence. This might be the most striking piece of data in this study—participants didn’t learn to update their decisions, even after they had completed the task a few thousand times.

These findings indicate that we have some tendencies that are difficult to overcome. They function like an unconscious confirmation bias: when the environment agrees with our existing bias, it is confirmed; when there’s a conflict, the bias gets retained. The researchers cautiously suggest that perhaps if subjects were given stronger incentives, they would be better able to adapt to the feedback of actual experience, but this hypothesis wasn’t tested.

In terms of day-to-day applicability, this data suggests that when we make a bad choice supported by an intrinsic bias, we may be immune to adapting for a better outcome in the future. These findings, however, are specific to this visual choice test and may not necessarily be widely generalizable—more experiments will be needed before we can tell how this phenomenon affects our other bad choices in life.

PNAS, 2016. DOI: 10.1073/pnas.1518786113 (About DOIs).