Serendip is an independent site partnering with faculty at multiple colleges and universities around the world. Happy exploring!

Beautiful People, Ghosts and Deceased Relatives: The Nervous System and Perception

anonstudent01's picture

"Perhaps we are hallucinating all the time and what we call perception is arrived at by simply determining which hallucination best conforms to the current sensory input." V.S. Ramachandran here communicates the uncomfortable notion that what we perceive to be real is not reality at all. My body as I know it may really have a different form entirely, I may be typing into nothingness and the ghost that I’m sure I saw at summer camp may have been more real than I am. Maybe new agers do contact extra terrestrials and your dead relatives never really leave your side. Maybe. Does a distinction need to be made between the nervous system and the mind or between sensory-input and possible extra-sensory perception/ hallucinations? My philosophy teacher senior year told us that the difficult decision before anyone who takes these possibilities seriously is whether or not to accept and continue with life as prescribed by our sensory input or to reject it and be skeptical for the rest of our lives. I don’t agree with him, I think that heightened awareness of these possible alternate realities can likely enrich our own perceived reality and I hope that exploring these questions will help me to do so.

We have seen this example dozens of times at the movies and likely in life as well: a beautiful woman walks down the street and several men take visible and often exaggerated notice of her. If her combination of a beautiful face and body is recognized by so many individuals, how can it not be real? Are all of them actually seeing the exact same image on the same plane of reality? “When we look at an object with two eyes, we perceive it as singular, like we do other parts of the visual scene stimulating points on our retina that share a common visual direction. These points are termed "retinal corresponding points" and fall on an area called the "horopter". Points outside the horopter fall on slightly different retinal areas and so do not have the identical visual direction and lead to "retinal disparity", the basis of our depth discrimination. This retinal image disparity occurs due to the lateral displacement of the eyes (3).” So then do all of the men, who are passing at different distances, share common visual direction, retinal disparity and depth discrimination with which to perceive her “edges”? If indeed they do, then they also must have received similar societal or biological information about what is attractive and they must have collectively developed and successively act upon this ideal. Is perception of the woman the most complementary hallucination to current sensory input and not in fact reality?

Another major question surrounding vision is the perception of supernatural beings or forces that may be beyond this reality or dimension. Ghost sightings have been reported for thousands of years. Shapes can be deduced in the tea leaves at the bottom of a coffee cup or in the clouds over our heads. Some athletes never wash their game day socks so as not to offset a providential spirit. People from many different cultures claim to have been in the presence of some spirit, be it a shadowy form or an invisible yet tangible force. Are these presences or perceptions really unexplainable paranormal phenomenon? Or are they actually all around us but not accessible to our visual perception due to constraints from our nervous system- one hallucination selected over another? It turns out that with ghosts it is more necessary to first believe in order to perceive supernatural phenomena, as it seems to be with most beliefs in otherworldly beings. “The ubiquity of such beliefs is actually a clue to how the normal mind works, cognitive scientists now realize, for belief in the supernatural arises from the same mental processes that underlie everyday reasoning and perception. Chief among those normal processes is our neurons' habit of filling in the blanks. The brain takes messy, incomplete input and turns it into a meaningful, complete picture. The mind also tends to impute consciousness to inanimate objects (ever yell at a balky computer?). This leads us to believe that natural phenomena are purposeful, caused by agents with sentient minds (1).”

There also is apparently a strong correlation between belief in supernatural beings or forces and the belief in dualism. In the beginning of the course we discussed the idea of dualism as the equivalence between the nervous system and the mind and whether understanding the nervous system was enough to explain behavior. If the nervous system controls our perception of all sensory input, then is the mind or I-function separate from the nervous system and necessary for perception of activity outside of this dimension or reality? “The belief that minds are not bound to bodies reflects a dualism that shows up in children as young as 2. “This is universal, seeing minds as separate from bodies,” says psychologist Paul Bloom of Yale University. “Kids have no trouble believing stories in which people exchange bodies, for instance. And since supernatural beings like ghosts are without material bodies but with minds, our belief in dualism makes them totally plausible (1).” If you open yourself (using your I-function to influence the other boxes in your nervous system) then you are more likely to come in contact with things beyond our experienced dimension or reality. The same probably goes for those who operate in ‘the field’ and contact extra terrestrials- first enlightenment via concentrated openness is necessary. Is this opening of other boxes accepting alternate hallucinations and thus alternate perceptions?

The death of a loved one can not only be emotionally devastating but also reality-changing. When someone whom you are bound to emotionally and physically passes away permanently from your reality, it is not uncommon for reality to make a shift in an effort to encompass them still. A common example is the case of a wife who lost her husband after thirty years of marriage who claimed that he was in her field of vision constantly, as though he placed himself in every situation she found herself in. This may be a return to the belief in the dualism of mind and brain which may facilitate the perception of a deceased person’s presence. A study was conducted to compare the personality constructs associated with the experience of perceiving the presence of deceased loved ones, including both male and female subjects. “As hypothesized, perceivers exhibited higher scores on neuroticism and externalized control; contrary to expectations, perceivers demonstrated more extroversive than introversive tendencies. Perceived presence was not mediated by the quality of support available to the perceiver, was not generally correlated with specific demographic factors, and was most often characterized as comforting (2).” This is what I would consider a very formal Western approach to this issue which touches beyond practical data collection and clinical comparison. However it does provide citable characteristics of perception which may help indicate the accessibility of an alternate reality by the nervous system or another box to provide comfort.

The human nervous system has developed for millennia in order to best serve the survival and function of our species. The human experience of reality has always been informed by sensory perception and most likely has been honed to include some aspects of reality and not others as is made clear by these gathered observations. So then do we accept what the nervous system allows us to experience? It is true that we will physically never be capable of altering the imaged reality that is created by the nervous system in our visual “hole,” nor will we be able to consciously force ourselves to see something in a higher dimension. However, if we question our sensory input and consciously accept unexplainable phenomena that may be beyond our prescribed reality, there is always the possibility of expanding our reality or perhaps even experiencing a different hallucination.


1. Begley, Sharon. “The Ghosts We Think We See.” Newsweek. 27 Oct 2007.

2. Datson SL, Marwit SJ. “Personality constructs and perceived presence of deceased loved ones.” Pub Med. <>

3. “The Perception of Space.” Webvision: John Moran Eye Center, University of Utah.


Paul Grobstein's picture

reality and hallucinations

So ... which is it? "expanding our reality" or "experiencing a different hallucination"? Is there a difference that makes a difference?