Julia Papiernik-Kłodzińska^1,2, Simon Hviid del Pin³, Michał Wierzchoń^1,4, Marisa Carrasco^5,6, Renate Rutiku¹; ¹Consciousness lab, Institute of Psychology, Jagiellonian University, Krakow, Poland, ²Doctoral School in the Social Sciences, Jagiellonian University, Krakow, Poland, ³Norwegian University of Science and Technology, Gjøvik, Norway, ⁴Centre for Brain Research, Jagiellonian University, Krakow, Poland, ⁵Department of Psychology, New York University, ⁶ Center for Neural Sciences, New York University

Whether the primary visual cortex (V1) plays a role in working memory performance remains unclear. We explored this question by testing whether polar angle asymmetries, namely the vertical meridian anisotropy and horizontal-vertical asymmetry, along with visual field asymmetries (upper-lower and left-right) are reflected in individual working memory performance variation across the visual field and compared them against the individual brain structure. 262 participants performed an object recognition working memory task, adjusted to measure the visual asymmetries. Additionally, all participants underwent a structural MRI scan during a separate session. We used a multiparametric mapping sequence to acquire four different brain maps per participant: MT, PD, R1, and R2*, each contrast denoting different aspects of the brain microstructure. The regions of interest were V1, the intraparietal sulcus (IPS), and the frontal eye field (FEF), with the first one known to reflect the polar angle and visual field asymmetries, and the latter two known to be linked to working memory processing. The behavioral results show, that the working memory performance is impacted both by the visual field and polar angle asymmetries, with the vertical meridian anisotropy appearing reversed compared to the previous literature. The MRI results showed that the individual asymmetries in visual working memory performance do not explain the differences in the volume of FEF and IPS. On the other hand, the differences in volume of V1 were impacted by the vertical meridian anisotropy, with significant results present in three out of four MPM maps, and R2* results being the most systematic. This suggests that V1 plays a role in working memory performance, as well as that there may be a link between the iron content in V1 tissue, and the elevated polar angle asymmetry in visual working memory.

Acknowledgements: This work was supported by the National Science Centre, Poland (projects 2021/42/E/HS6/00425 to Renate Rutiku and 2017/27/B/HS6/00937 to Michał Wierzchoń for data collection) and by the European Cooperation in Science and Technology (COST, Action CA18106).