The strong dualism position of Descartes suggests that the mind is fully separate from the brain, and that, therefore, there may be no detectable manifestation of representations in the brain. What some note as manifestations are called traces, and their existence has been argued over time. Brain scans suggest that nothing we remember can be physically pinpointed in the brain. What is the best way in which I can make a comparison between differng conceptualizations of the mind and how it is studies? Also, Are there ways in which the influence of internal and environmental conditions affects memory? How can I determine the necessity for a one-to-one correspondence between a specific representation in the mind and a physico-chemical condition in some specific neurons/synapses in the associated brain and analyze fundamental differences between representations from: (a) Visual stimuli vs. those from speech stimuli; (b) Experienced stimuli (instantiated; things that happened externally, the last pizza you ate) vs. imagined stimuli (uninstantiated; anticipating-imagining something for dinner that you've never had before)?