TY - JOUR T1 - Interpreting dynamics of neural activity after dimensionality reduction JF - bioRxiv DO - 10.1101/2022.03.04.482986 SP - 2022.03.04.482986 AU - Timothée Proix AU - Matthew G. Perich AU - Tomislav Milekovic Y1 - 2022/01/01 UR - http://biorxiv.org/content/early/2022/03/07/2022.03.04.482986.abstract N2 - Recorded activity of cortical neurons during behavior is often analyzed with dimensionality reduction methods. The resulting oscillatory trajectories have been interpreted as signatures of latent oscillatory dynamical systems. Here we show that oscillatory trajectories arise as a consequence of the horseshoe effect after applying dimensionality reduction methods on signals that approximately exhibit continuous variation in time, regardless of whether latent oscillatory dynamical systems are present or not. We show that task-relevant information is instead contained in deviations between oscillatory trajectories, which we account for by introducing a new model that goes beyond the dichotomy between representational and dynamical systems models of neural activity. Our findings help interpret the results of dimensionality reduction analyses.Competing Interest StatementThe authors have declared no competing interest. ER -