Dr Gellersen attended Jacobs University Bremen and Maastricht University for undergraduate and graduate degrees in cognitive psychology and neuroscience. She received her Doctorate in Psychology from the University of Cambridge. Her postdoctoral experience includes positions at the Clinical Cognitive Neuroscience group at the German Centre for Neurodegenerative Diseases in Magdeburg and the Department of Psychology and the MRC Cognition and Brain Sciences Unit at the University of Cambridge.
Dr Gellersen is a supervisor for undergraduate and graduate dissertation projects in psychological and natural sciences. She also delivers lectures for the "Improving Scientific Practices in Cognitive Science" course that is part of the MPhil in cognitive neuroscience at the MRC Cognition and Brain Sciences Unit.
Dr Gellersen is a cognitive neuroscientist studying how healthy ageing and the earliest stages of Alzheimer’s disease alter brain function and memory processes. Memories vary widely in terms of the amount of detail recalled, yet most prior studies use simple binary (correct vs. incorrect) measures. During her PhD, she designed new tests to assess the fidelity with which people recall information, through which she uncovered cognitive processes that explain inter-individual differences in memory precision across the lifespan. During her Fellowship at St John’s College, Dr Gellersen is using functional MRI to identify the neural underpinnings of memory fidelity in healthy ageing and to determine features of brain dynamics that can explain youth-like performance even into old age. In collaboration with the German Centre for Neurodegenerative Diseases, Dr Gellersen will test whether memory fidelity tasks are promising for early detection of the pre-clinical phase of Alzheimer’s disease where individuals do not yet show obvious cognitive decline but harbour silent brain pathology. Using novel high-resolution neuroimaging methods, Dr Gellersen is obtaining a precise characterisation of the effects of pre-clinical pathology on memory systems at an unprecedented resolution. These insights are crucial to improve current memory tests for screening of at-risk older adults and monitoring potential treatment effects.
Gellersen, H. M., McMaster, J., Abdurahman, A., & Simons, J. S. (2024). Demands on perceptual and mnemonic fidelity are a key determinant of age-related cognitive decline throughout the lifespan. Journal of Experimental Psychology: General, 153(1), 200.
Luppi, A. I., Gellersen, H. M., Liu, Z. Q., Peattie, A. R., Manktelow, A. E., Adapa, R., ... & Stamatakis, E. A. (2024). Systematic evaluation of fMRI data-processing pipelines for consistent functional connectomics. Nature Communications, 15(1), 4745.
Gellersen, H. M., Trelle, A. N., Farrar, B. G., Coughlan, G., Korkki, S. M., Henson, R. N., & Simons, J. S. (2023). Medial temporal lobe structure, mnemonic and perceptual discrimination in healthy older adults and those at risk for mild cognitive impairment. Neurobiology of Aging, 122, 88-106.
Gellersen, H. M., Guo, C. C., O’Callaghan, C., Tan, R. H., Sami, S., & Hornberger, M. (2017). Cerebellar atrophy in neurodegeneration—a meta-analysis. Journal of Neurology, Neurosurgery & Psychiatry, 88(9), 780-788.
