Context Matters: Memories of Prior Times

It’s not just the answer to the question Do you love me? that determines the fate of two people. When the answer takes too long, even a positive response can induce negative emotions. This highlights our ability to track, and the importance of tracking the passage of time. In this thesis, I demonstrate that the perception of a duration is influenced by previous experiences (the “Typing…” message in a WhatsApp group with one’s parents just takes an eternity after just having chatted with friends) and that this finding is a highly robust phenomenon. To counter a number of implausible assumptions in existing mathematical models of how memory is involved in the perception of time, I propose an extension to these mathematical Bayesian models of timing that implements a more realistic memory representation. Additionally, in a series of experiments in healthy aged populations and patients diagnosed with amnestic mild cognitive impairment (aMCI), I show that the temporal memory effects are directly linked to memory proficiency: the more memory is clinically affected - for example due to the early stages of Alzheimer’s - the more one relies on earlier experiences instead of on the currently perceived duration. This paradoxical finding could potentially be used as an indirect yet sensitive measure to track declining memory before aMCI, a precursor to Alzheimer’s, is officially diagnosed