Is your brain lying to you? Here's why your memory may not be accurate

The Citizen

28-07-2025

The brain has evolved to prioritise processing speed, efficiency and emotional stability over factual accuracy.
Seeing is believing. Thinking is believing. But not quite. Because even though you may be convinced of a certain reality and truth, it may not be the same for anyone else. Your brain is an expert editor and, if your life was like a movie, thank your largest organ for customising it to a personalised box-office hit.
This is, because despite its brilliance of design, the brain is not a reliable narrator. It is less of an objective observer and more of a creative writer instead. It's always snipping, molding and rearranging stuff to suit the story it wants to tell you, and the rest of the world, for that matter.
The human brain is designed for survival, not truth.
Your brain is not wired for truth
Psychologist and medical doctor Dr Jonathan Redelinghuys said that the brain has evolved to prioritise processing speed, efficiency and emotional stability over factual accuracy. However, by doing so, it often distorts reality through illusions, biases and misremembered events. These selective edits are not acts of ill intent but rather protective mechanisms that help us make decisions quickly and feel better about ourselves.
Dr Redelinghuys said we hardly ever realise that our brain is duping us. 'Our brains aren't trying to deceive us out of spite,' he said. 'They're doing their best to keep us functional. But shortcuts for efficiency's sake can come at the cost of accuracy.'
One of the more common ways this mental sleight of hand shows up is through cognitive bias. It's like a mental trick that feels like logic to you, but it isn't really.
American psychologist Raymond Nickerson said in a research paper that people are far more likely to notice and remember information that supports their own beliefs, while conveniently ignoring anything that doesn't. This kind of bias meddles in almost everything in your life from who you vote for, to your opinion on load shedding, rugby, ham, or asparagus on pizza, and even the loud music your neighbour plays on a Sunday afternoon.
Same experience, different memories
Dr Redelinghuys said this is one of the reasons two people can have entirely different accounts of the same event, and both believe they are right. 'It feels like common sense at the time,' he said. 'But it's just your brain telling a story it wants to hear.'
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Endemic to many politicians is the Dunning-Kruger effect. Psychologists David Dunning and Justin Kruger ran a study 25 years ago that showed how people with limited knowledge or skill in an area tend to overestimate their competence. Ironically, people who know their stuff, often underestimate their own abilities.
'It's not arrogance,' said Redelinghuys. 'It's that people who don't know enough are also the least equipped to notice how little they know.'
In line with misplaced convictions, a 1975 study found that people often believe they can control outcomes that are purely random. This is why gamblers always think they are in for a win in the next spin or hand and why, somewhat stupidly, people who tap elevator buttons more than once believing, deep down, it will come faster.
Dr Redelinghuys said the brain prefers a world that makes sense, even if it must invent that order entirely. 'We want predictability,' he said. 'So, the brain edits in control, even where there is none.'
Memories more like scrapbooking than library
Memories too, are not filed as if it were books in a library. Scrapbooking is a better description of what really happens. American cognitive psychologist Elizabeth Loftus said that people could be led to form entirely false memories.
One experiment convinced participants they had been lost in a mall as a child. This even though that never happened. 'Memory is not a record of the past,' said Redelinghuys. 'It's a reconstruction that changes every time you call it up.'
And then there is something called a flashbulb memory. It's recollections from emotionally charged events like for example, the 11 September World Trade Centre attack in 2001. While people reported on their own memories of the day and events with great confidence, researchers found the details often inaccurate.
'Confidence and correctness are not the same thing,' said Redelinghuys. 'You can be absolutely sure, and absolutely wrong.'
More than a party trick
Neuroscientist David Eagleman wrote in a 2001 study that visual illusions are not just party tricks either. They reveal how much of what we see is actively constructed by the brain. The famous blind spot in our vision is a literal gap in the data coming into our eyes. The brain just fills in the blanks without telling us.
'You're not seeing everything that's there,' said Dr Redelinghuys. 'You're seeing what your brain has predicted should be there.
'Once you realise how much of your reality is constructed, you can begin to question your assumptions and become a better decision-maker,' said Dr Redelinghuys. 'It requires rewiring your way of thinking to compensate for your brain's flaws, and then to use them effectively and impactfully in your life.'
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