The world seems different in a social context: a neural network analysis of human experimental data

TL;DR

This study uses a neural network model inspired by predictive coding to replicate and analyze how social context influences human perception, revealing differences in neural coding and the role of prior and sensory information.

Contribution

It demonstrates that social versus non-social perception differences can be explained by adjusting prior and sensory signal precision in a neural network model, suggesting a continuum of social influence.

Findings

Behavioral differences explained by prior and sensory precision adjustments

Neural activation patterns differ between social and individual conditions

Model replicates human data across social and non-social settings

Abstract

Human perception and behavior are affected by the situational context, in particular during social interactions. A recent study demonstrated that humans perceive visual stimuli differently depending on whether they do the task by themselves or together with a robot. Specifically, it was found that the central tendency effect is stronger in social than in non-social task settings. The particular nature of such behavioral changes induced by social interaction, and their underlying cognitive processes in the human brain are, however, still not well understood. In this paper, we address this question by training an artificial neural network inspired by the predictive coding theory on the above behavioral data set. Using this computational model, we investigate whether the change in behavior that was caused by the situational context in the human experiment could be explained by continuous modifications of a parameter expressing how strongly sensory and prior information affect perception. We demonstrate that it is possible to replicate human behavioral data in both individual and social task settings by modifying the precision of prior and sensory signals, indicating that social and non-social task settings might in fact exist on a continuum. At the same time an analysis of the neural activation traces of the trained networks provides evidence that information is coded in fundamentally different ways in the network in the individual and in the social conditions. Our results emphasize the importance of computational replications of behavioral data for generating hypotheses on the underlying cognitive mechanisms of shared perception and may provide inspiration for follow-up studies in the field of neuroscience.