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There are two distinctly different views on Quaternary sedimentation rates in the central Arctic Ocean, namely, that they were on cm/kyr or on mm/kyr scales, largely as a result of divergent interpretations of magnetic reversal stratigraphy. This study provides new evidence to help resolve this controversy in the form of an almost 1‐m‐thick negative polarity interval located at ~1.15 m below the seafloor in a 4.15‐m‐long sediment core from the Lomonosov Ridge, central Arctic Ocean. This thick polarity anomaly was first revealed through alternating field demagnetization of natural remanent magnetization on u‐channel samples. It was subsequently confirmed to be an authentic signal of a syndepositional geomagnetic field by integrating detailed rock magnetic studies, transmission electron microscopy with energy‐dispersive X‐ray spectroscopy analyses of magnetic extracts, and both alternating field and thermal demagnetization of discrete paleomagnetic samples. Here we conclude that it is more reasonable to interpret the reversed interval as a record of the Matuyama Chron rather than a Brunhes‐aged excursion, which yields mean sedimentation rates of ~1.5 mm/kyr and ~0.5 mm/kyr in the Brunhes and Matuyama Chrons, respectively. These estimates are remarkably lower than assumed in most recent studies, but in good agreement with both previous magnetostratigraphic and recent geochemical studies relative to the decay of Be and U‐series isotopes, which might indicate "sediment‐starved" environments at least in some parts of this region. Overall, our results not only imply that chronostratigraphy in the central Arctic Ocean remains open to debate but also warrant further investigations in this microfossil‐barren region. Key Points: The effects of self‐reversed CRM of diagenetic titanomaghemite are probably only regional in the central Arctic sedimentsThe "reversal" interpretation supports "sediment starved" environments at least in some regions of the central Arctic OceanThe chronostratigraphy and usability of paleomagnetism in the central Arctic Ocean remains open to debate and further studies are warranted [ABSTRACT FROM AUTHOR]