The Neural Representation of Counterfactual Thought

Project Awarded: $30,000

Many of the most interesting cognitive feats that humans perform require us to consider not just the things that actually occur, but also non-actual alternative possibilities. Such “counterfactual” thoughts pervade diverse forms of human cognition, from language to morality to causal reasoning, and others. Recent research has identified a set of neural processes involved in explicit, episodic counterfactual thinking; in other words, the deliberative simulation of non-actual events, whether in the past or the future (De Brigard, et al., 2013; De Brigard et al., 2015; Schacter et al., 2015). This work is foundational because it identifies the neural systems that underwrite episodic simulation. Yet, the counterfactual representations that support critical aspects of humans’ ability for language, judgement, and decision-making sometimes occur at an implicit rather than explicit level (Phillips & Cushman, 2017; Phillips & Knobe, 2018).

Our goal is to use fMRI to identify the neural representation of these implicit counterfactual possibilities. Moreover, we propose to adopt a novel approach to multi-voxel pattern analysis that affords stronger inferences about a genuine representational role. Drawing on debates about the nature of representation from philosophy (e.g., Ramsey, 2007; Dretske, 1997), we make a distinction between representational states and ‘mere tracking’ states in order to define empirically discoverable properties of representations. Our analysis protocol is designed to target this distinction and seeks to identify neural representations of counterfactual thought under this more rigorous definition of representation.

We propose to meet these goals through the following Specific Aims: (1) identify neural populations that encode the content of implicit counterfactuals; (2) differentiate the patterns of brain activity associated with implicit counterfactual thought from those associated with thinking about actual events; and (3) establish the representational function of the multivariate patterns identified in Aims 1 and 2.

Should we succeed in achieving our goals, our project will (A) provide the first evidence for how and where implicit counterfactual thought is instantiated in the brain, (B) provide a reliable neural assay of implicit counterfactual representation that can be exploited by researchers in psychology, cognitive science, and philosophy, and (C) demonstrate the ways in which philosophical insights can directly benefit neuroscientific research.

Regan Bernhard, PhD. Postdoctoral researcher in Psychology, Harvard University

Regan Bernhard, PhD. Postdoctoral researcher in Psychology, Harvard University

Jonathan Phillips, PhD. Postdoctoral researcher in Psychology, Harvard University

Jonathan Phillips, PhD. Postdoctoral researcher in Psychology, Harvard University

Jessey Wright, PhD. Postdoctoral researcher in Psychology, Stanford University 

Jessey Wright, PhD. Postdoctoral researcher in Psychology, Stanford University