Rendering aphantasia into the social realm

Abstract

Inspired by an analogy with ‘game engines’, the software modules that support animations and games, Balaban and Ullman propose that there is a deep-seated distinction between ‘physical simulation’ and ‘graphical rendering’ in the brain, broadly mapping onto the dorsal and ventral streams of visual processing [1]. The developmental pathway giving rise to in silico game engines is very different from the evolutionary history of the human brain, constrained by evolutionary forces. Nevertheless, the analogy is illuminating. Balaban and Ullman suggest that recent findings from people lacking wakeful visual imagery (i.e. with ‘aphantasia’), can be explained with the help of this distinction: intact ‘physical imagery’ allows them to undertake the wide range of tasks that, perhaps surprisingly, are unaffected by aphantasia, for example, tasks involving spatial memory and spatial transformation, while their lack of conscious object imagery is explained by ‘broken rendering’. The suggestion is thought-provoking, but it creates a puzzle. As Balaban and Ullman write, if the ‘physics engine’ can achieve so much, ‘why bother? Why waste time and energy putting paint on a canvas that does not matter?’. We doubt that this elaborate ‘rendering operation’ is epiphenomenal. Nor is it likely to be as effortful as it might be in an artificial model with no evolutionary history. We propose instead that its key function may lie, unexpectedly, in a domain that Balaban and Ullman mention only in passing – the domain of social cognition.

Authors

• Adam Zeman20
• Bérengère Digard1
• Francesca Happé2
• Brian Levine6
• Merlin Monzel30

Rendering aphantasia into the social realm

Abstract

Inspired by an analogy with ‘game engines’, the software modules that support animations and games, Balaban and Ullman propose that there is a deep-seated distinction between ‘physical simulation’ and ‘graphical rendering’ in the brain, broadly mapping onto the dorsal and ventral streams of visual processing [1]. The developmental pathway giving rise to in silico game engines is very different from the evolutionary history of the human brain, constrained by evolutionary forces. Nevertheless, the analogy is illuminating. Balaban and Ullman suggest that recent findings from people lacking wakeful visual imagery (i.e. with ‘aphantasia’), can be explained with the help of this distinction: intact ‘physical imagery’ allows them to undertake the wide range of tasks that, perhaps surprisingly, are unaffected by aphantasia, for example, tasks involving spatial memory and spatial transformation, while their lack of conscious object imagery is explained by ‘broken rendering’. The suggestion is thought-provoking, but it creates a puzzle. As Balaban and Ullman write, if the ‘physics engine’ can achieve so much, ‘why bother? Why waste time and energy putting paint on a canvas that does not matter?’. We doubt that this elaborate ‘rendering operation’ is epiphenomenal. Nor is it likely to be as effortful as it might be in an artificial model with no evolutionary history. We propose instead that its key function may lie, unexpectedly, in a domain that Balaban and Ullman mention only in passing – the domain of social cognition.

Authors

• Adam Zeman20
• Bérengère Digard1
• Francesca Happé2
• Brian Levine6
• Merlin Monzel30