A Near Infrared Spectroscopy Study of Counterfactual Thinking

Abstract

This thesis describes a study on counterfactual thinking, which refers to the ability to imagine scenarios that are contrary to fact. I investigated the neural correlates of realistic and unrealistic past counterfactual thoughts in bilateral regions of the frontal cortex with Near Infrared Spectroscopy. It was found that individuals take longer to make decisions about unrealistic counterfactual thoughts than realistic counterfactual thoughts and unrealistic causal thoughts. There were no differences in levels of most extreme percent change in hemoglobin for counterfactual and causal thoughts. Unrealistic thoughts corresponded to higher percent change maximums of oxygenated hemoglobin than realistic thoughts in the left hemisphere, but lower percent change maximums of oxygenated hemoglobin in the right hemisphere. Neural activity unique to counterfactual thinking does not appear to lie in the dorsolateral prefrontal cortex. However, the frontal cortex appears to play a role in differentiating realistic and unrealistic thinking.