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Doctor of Philosophy in Psychology, Alzheimer's disease (AD) is a pervasive neurodegenerative disease that can be difficult to diagnose accurately in the early stages of the disease. Pathological cerebrospinal fluid (beta-amyloid and tau) and hippocampal volume loss can be identified before the onset of cognitive deficits (e.g., learning and memory). The purpose of the present study is to investigate the relationship between learning, memory, and hippocampal volume in a preclinical, cognitively healthy AD population according to their beta-amyloid and tau biochemistry. Thirty-eight older adults (M = 76.32; SD = 6.84) completed body fluid sampling, neuropsychological assessment (including the California Verbal Learning Test, Second Edition [CVLT-II]) and neuroimaging (i.e., magnetic resonance imaging), and were classified into two groups according to a cut-off score of their beta-amyloid and tau ratio (2.7132): normal beta-amyloid/tau ratio (CH-NAT) and pathological beta-amyloid/tau ratio (CH-PAT). Statistical analyses revealed several key findings: (a) decreased hippocampal volume was correlated falling beta-amyloid and rising tau, (b) CVLT-II List B and Trial 1 were associated with changes in increased beta-amyloid and decreased tau, (c) a flatter learning curve was associated with decreased hippocampal volume, (d) left hippocampal volume was correlated with memory retention, and (e) recognition memory was related to decreased white matter and right hippocampal volume. The present study reinforces the growing evidence of early changes of beta-amyloid and tau biomarkers, hippocampal and white volume, and verbal learning and memory among participants with preclinical AD.