Why dreams make no sense: Region of brain used to understand the world around us switches off
- Experts at the University of Milan linked the strangeness of dreams to psychosis, because people become disconnected from reality
- Brains of volunteers who kept dream diaries were scanned in experiment
- Found part of the brain switches off when its bombarded with strangeness and that dreams were far more bizarre than self-concocted fantasties
From impossible landscapes to talking animals and supernatural acts, our dreams can be downright bizarre.
Now, a new study suggests that strange events seem normal when we dream because part of our brain has given up trying to work out what is going on.
Italian researchers have controversially linked the weirdness of dreams to psychosis, because people become disconnected to reality and easily jump to the wrong conclusions.
A new study suggests that strange events seem normal when we dream because part of our brain has given up trying to work out what is going on. A stock image of a surreal dream landscape is shown
The study, published in the Journal of Sleep Research, says: ‘The story-like organisation of dreams is characterised by a pervasive bizarreness of events and actions that resembles psychotic thought, and largely exceeds that observed in normal waking fantasies.’
Armando D’Agostino of the University of Milan and his team asked 12 volunteers to keep a dream diary in which they described vivid accounts of seven dreams, New Scientist reported.
The researchers scored the dreams using a ‘bizarreness’ scale they had come up with and discovered that the volunteers’ dreams were far stranger than the fantasies they deliberately concocted.
Italian researchers have controversially linked the weirdness of dreams to psychosis, because people become disconnected to reality and easily jump to the wrong conclusions. A stock image of a dreaming woman is shown
BRAIN SCANS REVEAL WHY WE JUMP TO CONCLUSIONS
Neuroscientists have identified the part of the brain that’s responsible for ‘one-shot learning’ and say that we are most likely to jump to conclusions when we are uncertain about a situation.
Experts at California Institute of Technology (Caltech) in Pasadena, have discovered that uncertainty in terms of the causal relationship – whether an outcome is actually caused by a particular stimulus – is the main factor in determining whether or not rapid learning occurs.
They say that the more uncertainty there is about the relationship, the more likely it is that one-shot learning will take place.
When that uncertainty is high, they suggest that humans need to be more focused in order to learn the relationship between stimulus and outcome.
The researchers also identified a part of the prefrontal cortex – the large brain area located immediately behind the forehead that is associated with complex cognitive activities – that appears to evaluate causal uncertainty and enable us to jump to conclusions when needed.
The researchers used a simple behaviour task paired with brain imaging to determine where in the brain this causal processing takes place, and pinpointed the ventrolateral prefrontal cortex.
It appears to process information before coupling with the hippocampus to switch on one-shot learning, as needed.
Dr D’Agostino said: ‘It seems counterintuitive, but there was almost no bizarreness in fantasies,’ adding that people’s tales were written within logical constraints.
A month after completing the diaries, the brain activity of the volunteers were monitored using an fMRI scanner.
The dreamers listened to their own narrative reports and attempted to relive the experiences.
The experts found that the dreams and fantasies seemed to activate regions in the right hemisphere of the brain, usually associated with processing words and meanings, as well as reasoning.
‘In respect to non-bizarre reports of daytime activities, the script-driven recall of dreams and fantasies differentially activated a right hemisphere network including areas in the inferior frontal gyrus and superior and middle temporal gyrus,’ the study says.
Interestingly, the activity decreased the stranger the stories or dreams became, as if the brain was giving up trying to understand them.
‘Neural responses were significantly greater for fantasies than for dreams in all regions, and inversely proportional to the degree of bizarreness observed in narrative reports,’ the study says.
Commenting on the research, which was published in the Journal of Sleep Research, Patrick McNamara at Boston University said that dreams may be stranger because they might act as symbols in a process that stores memories, so that weirdness may result from the brain’s attempts to symbolise strong or confusing emotions.
However, Bill Domhoff of the University of California, Santa Cruz told the publication that because not all dreams are strange, dreaming can’t be said to be hallucinatory and psychotic. ‘It is an intensified form of mind-wandering,’ he added.
The experts found that the dreams and fantasies seemed to activate regions in the right hemisphere of the brain (illustrated above), usually associated with processing words and meanings, as well as reasoning.