Interpreting Mental Rotation Performance in Self-Described Aphantasia through Cognitive Penetrability

Abstract: Mental images are unique mental representations and the depictive view in the imagery debate states that mental images have similar spatial structures as their corresponding external object. The propositional view, however, contends that beliefs about the external world influence a mental image – also known as the cognitive penetrability theory –, therefore mental images cannot be described in visual terms. People with self-described aphantasia, those considered lacking visual mental images, offer a new opportunity to approach this issue. The current study employed the mental rotation task (MRT), where a three-dimensional object needs to be mentally aligned with another one that is rotated to a different angular position. To test the effects of beliefs on mental images, different instruction conditions were used on the MRT. Twenty-seven participants (21 females, mean age 47 years) with self-described aphantasia completed an online experiment, consisting of the MRT, the Object-Spatial Imagery Questionnaire (OSIQ), and the Vividness of Visual Imagery Questionnaire (VVIQ). While participants scored low on the VVIQ and higher on the spatial items than on the object items of the OSIQ, the key finding was that increasing reaction time with increasing angular disparity on the MRT was not influenced by different instruction types. This suggests that the theory of cognitive penetrability is not applicable on mental rotation in aphantasia, highlighting the importance to revise how mental images (or the lack of them) are understood and described.