# Information Measures of Redundancy and Synergy in Neural Activity

**DOI:**https://doi.org/10.1007/978-1-4614-6675-8_162

## Definition

Two descriptions of an underlying signal should be expected to be more informative than either one of the descriptions itself. However, several scenarios can be imagined. First, if the two descriptions each represent independent aspects of the underlying signal, then the two descriptions should be twice as informative as any one by itself. Second, if the two descriptions provide partially overlapping information, then the two descriptions together should be *less than* twice as informative as any one by itself. In this case, we say that the two descriptions are *redundant*. A third scenario requires a somewhat more specific setup. Namely, suppose now that each description provides a *noisy* version of the underlying signal, but with different noises. Then, it could happen that the two noises cancel each other out and, hence, that the two descriptions together are *much more*than twice as informative as any one by itself. A similar observation applies if the noises only...

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