Emaad Razzak¹, Tengyu Song¹, Elmina Aghayeva¹, Jiayi Wang¹, Tim Mousseau¹, Jacqueline Gottlieb¹, Alfredo Spagna¹; ¹Columbia University

Visual mental imagery (VMI) generates representations of absent stimuli; visual working memory (VWM) maintains this information. These processes are concurrently engaged in tasks exemplified by planning furniture arrangement. Their interaction—collaborative or competitive—remains elusive. We developed a delayed match-to-sample mental rotation task tapping VMI and VWM concurrently through behavioral, subjective, and psychophysiological indices. Typical imagers (VVIQ > 32) performed a novel task based on Shepard and Metzler’s 3D stimuli, determining whether two rotated objects (varying by 0°, 60°, 120°, or 180° and presented simultaneously or sequentially with a 1s delay) were identical or mirrored. 2D analogs assessed spatial complexity. Metrics included accuracy, RTs, gaze patterns, pupillometry, subjective vividness, confidence, and strategy ratings, analyzed via repeated-measures ANOVAs. Accuracy decreased with VWM demand, 3D objects, and larger angles, especially at larger angles in 3D trials (ps < 0.001). Subjective vividness declined with VWM trials, 3D objects, and greater angles, (ps < 0.001), more steeply with larger angles and VWM demand (p < 0.01). Participants preferred a mental rotation strategy over logical reasoning (p < 0.001). RTs increased with angle (congruent with canonical findings) and 3D objects (ps < 0.001). Pupillary dilation occurred with greater angles and VWM demand, indexing higher cognitive effort. Gaze tracking indicates inspection of the empty first stimulus location in VWM trials (p < 0.001), suggesting imagery-based memory reinstatement. VMI and VWM may interact, shaping performance. The interaction between VWM and angle on vividness suggests reduced capacity to maintain vivid representations under combined demands, illustrating cognitive resource limitations. Pronounced accuracy decline with greater angles in 3D conditions underscores spatial complexity’s role in straining mental manipulation. Interestingly, eye tracking investigations suggest imagery-based reinstatement of prior stimuli in mental comparison. These results have significant implications for understanding cognitive resource allocation in tasks requiring complex visuospatial reasoning without immediate availability of visual information.

Acknowledgements: Recruitment of participants was made possible by funding from Brain Research Apprenticeships in New York at Columbia (BRAINYAC) 2024.