Monday's Seminars welcome Gaën PLANCHER, Professor junior member of the Institut Universitaire de France, Université Lumière Lyon 2

When: March 30th 11 am

Where: Salle des Voûtes 

Welcoming coffee 15' before

Title: Thinking without images: Does aphantasia reveal another way of reasoning?

Abstract:

The ability to generate and manipulate mental images is generally considered central to

human cognition. However, a major debate in cognitive psychology has pitted the

hypothesis of symbolic, abstract, and amodal representations (Pylyshyn, 1981) against

that of pictorial, perceptual, and analogical representations (Kosslyn et al., 1995). The

renewed interest in aphantasia, defined as an absence or marked reduction in visual

mental imagery, sheds new light on this debate. People with aphantasia report relying

more on abstract or verbal representations, which could be an advantage in high-level

reasoning tasks and correspond to a more “semantic and factual” cognitive style, in

contrast to the “episodic and sensory” style associated with hyperphantasia (Zeman et

al., 2020). We are currently conducting several studies to determine whether aphantasia

constitutes a distinct cognitive style and whether it confers specific advantages. During

my seminar, I will present results that have enabled us to identify two subgroups of

aphantastic individuals: one characterized by a more spatial profile, the other by a more

verbal profile. These profiles are distinguished by diZerent behavioral performances,

particularly in reasoning tasks. These initial results prompted a second series of studies

devoted to reasoning, inspired by the Visual Imagery Impedance Hypothesis (KnauZ &

Johnson-Laird, 2002). We replicated the eZect whereby visual imagery can slow down

abstract reasoning in individuals with typical imagery. However, this eZect was

attenuated in aphantastic participants. Taken together, these results support the

existence of distinct cognitive styles within aphantasia and reinforce the idea of multiple

representational formats that may influence cognitive performance.