Sensation Of Presence (Psychology): Causes And Associated Disorders
Throughout history and cultures, human beings have experienced phenomena that they were not able to explain, labeling them paranormal phenomena. This is due to the amazing capacity that the body has to make us live quite strange experiences, to which people try to give an acceptable meaning, most of the time from a cultural perspective.
Luckily, science has evolved enough to explain some of these phenomena, among which is the sensation of presence, or sense of presence, which will be talked about in this article. A sensation that, although disturbing, finds its explanation in brain functioning.
The feeling of presence is a perceptual distortion in which the person feels that they are not alone although there is no external stimulus that supports that sensation; The most representative case being that of a person who feels a presence behind them, which can be quite disturbing.
Although it is a phenomenon that occurs in the healthy population occasionally, it can occur in people with some very specific brain damage above all, and with more frequency and intensity, in people who tend to suffer hallucinations.
Perceptual distortions
The set of perceptual or imagination disorders are divided into two large groups: perceptual distortions and perceptual deceptions
Although these two terms agree that the person has an unusual perceptual experience, there are differences between the two. This difference lies in the fact that in perceptual distortions there is a stimulus but the subject experiences a distortion, and Perceptual deceptions are not based on real stimuli that exist outside the subject.
Since the sensation of presence is considered a perceptual distortion, this section will focus on its description.
How do these distortions appear?
These distortions are experienced by the person as a misperception of the reality around you. Usually, they occur when a stimulus that exists outside the person and is accessible to the sensory organs is perceived in a different and erroneous way than what would be expected according to the characteristics of the stimulus itself.
In these cases, The abnormality lies in the fact that the physical characteristics of what surrounds us, which are perceived in a distorted way. To classify an experience of this type as a cognitive distortion, two requirements must be taken into account:
As noted above, in cognitive distortions the anomaly tends to occur in the perception that the subject makes from a certain stimulus. However, sometimes these distortions have their origin in disorders with an organic basis usually temporary and that can influence both sensory perception and understanding at the level of the central nervous system.
In short, distortions are the product of a poor interaction between these three elements:
Causes and related disorders
In an experiment, detailed at the end of this article, the frontoparietal cortex and certain parts of the brain, such as the limbic system, associated with self-awareness, movement and the position of the body in space were identified as responsible. ; discovering that people who perceived this type of presence suffered from some type of damage or injury in these areas.
Commonly the feeling of presence is related to any of these alterations or disorders:
Regarding the healthy population that suffers this type of experience, it is usual for it to occur in times of stress or extreme fatigue or in single people with a very drastic decrease in environmental stimulation.
In the event that it becomes a recurring, long-lasting event, or is accompanied by other sensations or symptoms it is advisable to go to the referring doctor for an evaluation.
The importance of carrying out a psychiatric or psychological evaluation in these cases lies in three points:
Its possible association with other signs or symptoms
It is a sign of a high emotional state.
They can alert clinical staff to the existence of an etiological basis for this perceptual alteration.
The Lausanne experiment
In 2014, a team of researchers from the Federal Polytechnic School of Lausanne (EPFL) was able to determine some brain areas presumably related with this unique and disturbing sensation.
Likewise, this group of scientists developed an experiment that replicated this feeling of closeness of a strange entity in people.
The test began with performing a brain scan on 12 people who suffered from some neurological disorder and who reported having presented this sensation of presence. Through this scan it was discovered that all had some kind of damage to certain parts of the brain whose functions are related to self-awareness, movement and body position.
Next, the researchers managed to recreate the feeling that the person has when they perceive a sensation like this. To do this, they used 48 healthy volunteers who had never noticed this presence and exposed them to an experiment that altered neuronal signals in these same brain regions
The first step of this test consisted of covering the participants’ eyes, after which they were asked to manipulate a robotic system with their hands. As another robot did it traced exactly the same movements on the volunteers’ backs
When these movements took place at the same time, the test participants did not feel anything strange. However, when there was a delay between both movements, a third of the participants reported feeling a kind of presence in the room
Such was the shock caused to some of the people that they even asked to stop the experiment.
The explanation lies in the fact that the human brain has different representations of its own body in space, and in normal situations it has no problem developing a unified perception of the self. However, when this system malfunctions can lead to a second representation of one’s own body perceiving it as the presence of another different person but who cannot see.
The group of scientists theorized that when people perceive this ghost-like presence, the brain is actually getting confused; miscalculating the body position and, therefore, identifying it as belonging to another person or entity.
