Researchers at the University of Oxford’s Centre for Neural Circuits and Behaviour have discovered that:
“…nerve cells collect evidence for the alternative choices as minute voltage changes across their surface. These changes build up over time until they reach a hair-trigger point, at which the nerve cell produces a large electrical impulse. This impulse signals that a decision has been reached.” (Source)
Lead author of the study behind these conclusions, Dr. Lukas Groschner, says:
“We have discovered a simple physical basis for a cognitive process.
“Our work suggests that there is an important analogue component to cognition. People sometimes compare the brain to a digital machine operating with sequences of impulses and silences. But much of what looks like silence is actually taken up by analogue computation.” (Ibid)
The study, which can be found here, worked with a small number of nerve cells important for decision-making in fruit flies. One can imagine that similar processes occur in human brains.
If decisions are based on electrical charges that “build up over time” as analog computations, many aspects of thought become clearer. Indecision, abrupt decision, and mistakes as well as rational analysis all show signs of a mounting and wavering of voltage prior to decisive action. Frequently, the deciding “voltage” is an emotional burst or a bias.
It seems clear to me that decisions are built up over time (experience, training, rumination, unconscious accumulations) before they are made, often seemingly spontaneously.
As humans, we are particularly susceptible to a bias toward familiar or authoritative human semiotics. This is why propaganda works so well or why Google can swing an election without consumers of its products being aware they have been manipulated.
That humans copy and follow other humans is the basis of sociology and psychology. Culture is much like a Google algorithm that all but forces us to “decide” between limited options that have been “built up” over time by social inertia or manipulated by people who control social semiotics or the algorithms that select the ones we see.