What is noise? It is a threshold. A threshold at which point a signal loses its identifiability. Here, signal means meaningful activity which has a purpose or value. A group of people sitting at a bar, makes noise because of talking with each other relative to the silent state of the bar or relative to the music being played at that moment.
Noise may carry abstract meanings and may carry various threshold functions such as noise in public decision enquettes or unrelated information on a subject you are trying to make a decision.
If we think of neural networks in our brains, these circuits make correct decisions although they get some garbage(noise) in their inputs, namely not very clear situtions.
Mysteriously, noise may decide what is wrong what is right because it sets the environment to make a decision.
It eliminates what is relevant what is not according to the subject, it sets the boundaries of the elemnts that will make the decision.
Noise sets the threshold for making a decision. In situations where the input namely our observations of the phenomena around us are not clear, we try to clear things by changing or adjusting to the environment before we make decisions. In fact we solve the problem by adjusting the noise threshold. Noise may be necessary in order to make healthy decisions when the inputs are not completely clear.