What is the word for a connected web of brain cells whose bonds grow stronger the more you use them?

This question appear incomplete

Explanation:

This question appear incomplete because of the lack of options. However, a connected web of cells is generally referred to as the tissue. These cells are joined together by cell-cell adhesion (a form of bond) to form the tissue. The type of tissue being referred to here is the nervous tissue as this is the type of tissue present in the nervous system (including the central nervous system of which the brain is a part of).

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