Reality could be an illusion based on what our brains expect to see, according to controversial research.
Our internal mental simulation of the external world is only informed occasionally by real data from our senses, the theory claims.
If this is true, it means that we all experience the 'reality' in very different ways.
Our perception of reality could be an illusion based on what our brains expect to see, according to controversial research
The scientists have published a series of research papers in an open online portal called 'Philosophy and Predictive Processing', New Scientist reports.
Most researchers believe that our perception of reality is created in the brain from information sent by our eyes and ears. This phenomenon is called bottom-up processing.
But the latest research suggests reality is created inside our brains based on our prior knowledge and experiences - and then this 'influences' how we see the world.
This idea is known as top-down processing.
Because of this, much of what we interpret to be reality is actually mental fabrication.
For example, when you pick something up, the weight that you feel comes mostly from how heavy your brain expects the object to be, rather than the actual weight of it.
Evidence for this comes from previous research into how our brains perceive size-weight illusions.
In experiments, participant are given a big and small ball of the same weight.
Researchers have found that people often wrongly report that the big ball is heavier.
his phenomenon could be explained by how our expectations about the world impact our perception of reality.
'The idea that perception is partly driven by top-down processes is not new (which is not to deny that dominant theories of perception have for a long time marginalised their role),' Wanja Wiese and Thomas K. Metzinger, from Johannes Gutenberg University of Mainz, Germany, said in a research paper.
'The novel contribution of PP [predictive processing] is that it puts an extreme emphasis on this idea, depicting the influence of top-down processing and prior knowledge as a pervasive feature of perception, which is not only present in cases in which the sensory input is noisy or ambiguous, but all the time.'
The brain constantly monitors what is happening in our bodies and the environment to make guided guesses about what should be happening, according to the researchers.
The prediction that is thought most likely to represent reality is then prioritised by the brain.
They added: 'One’s brain constantly forms statistical estimates, which function as representations of what is currently out there in the world, and these estimates are hierarchically organized.'
The researchers said our predictions about what we should be seeing are based on a range of factors, including our individual experiences and emotional state.