As you read this, take a quick look around and pick out an object that catches your eye. Give it a good look. Look at it for a moment. Now close your eyes. Do you still see it? Can you picture it in your mind? How does it look? Is it as vivid as the real thing? Do you see colors and lines, shapes and textures, or does it seem fuzzy, somewhat less defined, even dull? As you picture it in your mind, see how long you can hold the image. How does it change over time? Does it seem to fade?
Now imagine a random object or scene from your childhood and ask yourself the same questions. How vividly can you ‘see’ it in your mind?
Some people can’t see anything. Nothing. Their mind’s eye is blank. They experience a nervous phenomenon called phantasy.
Delusion is a condition in which a person cannot visualize mental images. In other words, when they try to imagine or think about something they cannot create an internal mental image or picture. Because of this, people who experience daydreaming may have trouble recalling things like past experiences and the visual details associated with those memories. They also tend to struggle with tasks that require visualizing or imagining physical objects and how they move and rotate in space. This can have an impact on their spatial reasoning.
However, interestingly, a recent study shows that while people with delusions have deficits in object recall and memory, their spatial memory is not affected.
However, it is important to appreciate that daydreaming is not classified as a neurological or neuropsychological disorder. In general, it does not limit or hinder everyday life. However, for some people who experience daydreaming, it can cause frustration and limit their ability to do or remember certain things. It is not entirely known what proportion of the population has delusions, but current estimates suggest that about 4% of the population do.
What does one experience with fantasy?
So what does a delusional person actually experience? How would they describe it?
While each experience is unique and no two are exactly alike, the most prominent feature is the inability to “see” or picture anything in their mind, even when trying to recall a visual scene or object or any visual image. Beyond memory, they also lack the ability, or at least have difficulty, creating mental pictures or images.
For example, a person with delusions may not be able to imagine or remember something they may have seen in a movie. Or they may have great difficulty creating a mental picture of a description they read in a book or from a story they hear. Or events that happened to them in the past. Remembering faces is also difficult or impossible.
What causes it?
It is not fully understood what causes delusion and why some people simply cannot see, imagine or recall mental images. There is evidence to suggest that daydreaming is the result of altered activity in various parts of the brain that process and create visual images and imagination. A highly distributed network of brain regions, including parts of the visual cortex, temporal lobe, and parietal lobe. These brain regions are involved in the processing and integration of visual information and are thought to play a key role in creating mental images. There may be structural and functional changes in specific networks of neurons and other nerve cells in these regions that function differently from people who can produce mental images.
The brain receives information from the outside world through its five senses. It then integrates this information into different brain regions and combines information between different sensory inputs to create an internal model of the physical environment. None of us actually have directly always by “seeing” what the physical world around us looks like, we can only interpret what it might be like from the internal model our brains and minds create. In people with delusions there is something about how the networks of neurons and other nerve cells are connected that makes it difficult for them to imagine or see visual images in their mind.
In one study, researchers measured the brain waves of a daydreaming person using electroencephalography (EEG). EEG was all within normal limits on a battery of neuropsychological tests, except for visual imagery. When asked to imagine and see things in his mind, the parts of the brain that would normally be involved in creating the experience showed less activity, while other parts of the subject’s brain were active. Specifically, brain activity started in temporal rather than frontal regions, and there was no activity in the occipital (visual) cortex or parietal regions.
There is still considerable debate about what functional changes in the brain cause delusion, and much research is focused on trying to synthesize and integrate the growing information and data available in order to arrive at a more comprehensive and unified understanding of how neurobiological changes lead to observed and measured cognitive effects.
There is some evidence that fantasy is inherited, but the extent to which the underlying genetics is unclear and remains a matter of ongoing research. While there may be a genetic component to daydreaming, the biological and cellular mechanisms linking possible genetic variations to the physiological processes that functionally and cognitively manifest as daydreaming are not understood.
Finally, it is important to note again that delusion is not a neurological or neuropsychological condition. While it may be frustrating and limiting in certain scenarios and for certain tasks, in general, it does not meet the criteria associated with its classification as a mental disorder, namely, impairment in activities of daily living, violation of social norms and inappropriate behavior, and the perception of personal stress. The last criterion is statistical rarity, which it does satisfy. But by itself it is not enough for a clinical classification. That said, though, it is possible that in combination with other life factors or clinical manifestations a person experiencing daydreaming may need clinical treatment or intervention, but on its own, daydreaming is not a clinical disorder. However, it provides an interesting window into how the brain works and the spectrum of mind functionality.