Perceiving Reality by Controlled Hallucination

A major research focus tries to understand how people perceive reality. Originally, perception was generally believed to be a process of directly perceiving the world as it is based on signals the senses send to the brain. In that hypothesis, the brain signals or perceives what the reality is by limited processing or finessing of sense inputs. Thus, when a person looked at an apple, the brain was believed to do limited processing of the visual input into a perception that it is an apple, which is food. That is considered a bottom-up process because the brain has a relatively limited effect on direct perceptions of reality and what the senses are sensing directly reflects reality. In this model, external sensory inputs from sense organs are the main drivers of perception and the brain plays a smaller role in perception.

A more recent hypothesis proposes an opposite way of processing sense inputs. In this model, the “prediction machine model”, the brain exerts a greater influence on what is perceived relative to sense inputs from the eyes, ears, skin, etc. Here, the brain processes sense inputs by making predictions about what is being sensed based on prior experience. When for visual input from looking at an apple, the brain considers hypotheses for what the apple is or could be. The visual input acts mainly as a way to transmit prediction errors to the brain. Such input to the brain acts to rectify incorrect brain hypotheses about what is being sensed. This is considered to be a top-down mechanism of perceiving reality because the brain is the primary reality-perceiving organ, not the senses.

Thus, in essence, the newer model is a process of controlled hallucination (brain hypotheses), not direct perception of reality by sense organs. This model holds that the reality we perceive is  not a direct reflection of the objective external world. Instead, we perceive our brain’s predictions of what is causing our senses to respond as they do. Because no two brains are alike,[1] no two perceived realities will probably be exactly alike. Over time with repeated experience, the brain gets better and better at being correct about what is perceived for many things, but not necessarily all things.

Relevance to politics

The implications of the more recent model for politics could be important. In politics, a person’s brain isn’t just perceiving an apple or smelling a rose. It is trying to discern reality from extremely complex inputs. Those inputs usually implicate one or more powerful unconscious influencers of reality, including a person’s morals, ideology, religion, identity, gender, race, tribe or party affiliation and their social situation. Perceptions of an apple involve a relatively high degree of predictive accuracy by the brain. Clinically healthy people do not mistake an apple for a hamster or an orange.

By contrast, a political speech, especially one intended to mislead and trigger automatic, irrational emotional responses, will lead to a broad spectrum of perceptions that range from perceptions of mostly or completely fact, truth or reason to mostly or completely lies, deceit, emotional manipulation or irrational reasoning. In politics, two minds will rarely or never perceive the same reality from the same complex input. Even a simple political input such as a Christian cross behind a speaker evokes responses that range from positive to negative.

The process of the brain getting better at guessing about perceptions of reality is important. For example, social media echo chambers tend to reinforce perceptions of facts, truths and sound reasoning, even if they happen to false, wrong or flawed. Over time, false, wrong or flawed perceptions are reinforced and become harder to correct. That has been confirmed by cognitive and social science research. That research is consistent with prediction machine model of the brain’s role in perceiving reality, and distorting it into something it isn't when the conditions for reality distortion or denial are present.

In politics, those conditions seem to be present all the time. Their effects arguably include great social damage due to false perceptions of reality.[2]

Source: Scientific American, September 2019

Footnotes:
1. As discussed here before, people vary in their range of experiences that constitute real hallucination. The brain structure associated with reality monitoring ranges from normal, to smaller to absent and that correlates with (not necessarily causes) different frequencies of perceived hallucinations. The machine prediction model of perception sees hallucinations as a form of uncontrolled perception, not as something the brain simply makes up from nothing. In hallucinations, sensory inputs, e.g., something a person sees or smells, are considered to be failing to correct the brain's hypothesis of reality when the brain makes a mistake and either perceives something that either isn't there or perceives a distorted version of something that is there.

2. With any luck, working out how the brain perceives reality just might lead to better ways of communicating that could minimize distortions of facts, truths and reason or logic. If that turns out to be possible, it might present a pathway forward that relies less on conflict and violence than would otherwise be the case. Although the human species has been becoming less violent and brutal over the centuries, that aspect of our nature could still lead to major disaster.