1. A method of detecting information stored in the brain of a subject comprising: presenting to said subject stimuli including: “probe” stimuli relevant to a situation under investigation for effecting in said subject a specific brain response when said subject has knowledge thereof; “irrelevant” stimuli not relevant to said situation; and “target” stimuli identified to said subject as being noteworthy, assigning a task that involves discriminating between target stimuli and other stimuli and communicating this discrimination through an overt response; detecting an electrical brain response from said subject in response to each of said stimuli; analyzing said electrical brain responses for uncovering said specific brain response therein; and comparing said electrical brain responses due to said probe, irrelevant, and target stimuli for detecting the presence or absence of said information in said subject's brain based on the presence or absence of said specific brain response in response to said probe stimuli, wherein said analyzing and comparing of said electrical brain responses include at least one of the following techniques: bootstrapping on unweighted double-centered correlations; bootstrapping on single-centered correlations; bootstrapping on positive areas under a part of the brain-response waveform; bootstrapping on negative areas under a part of the brain-response waveform; bootstrapping on a combination of positive and negative areas under different parts of the brain-response waveform; bootstrapping on positive peaks; bootstrapping on negative peaks; bootstrapping on the difference between positive and negative peaks; covariance with a template; correlation with a template; stepwise linear discriminant analysis; dynamical systems (chaos) analysis; bootstrapping on the frequency spectra.