A Critical Review of Dr. Oasis's Apparitional Case

Elliott Van Dusen

Rhine Education Center 

A Skeptical Approach to Parapsychology 

December 9, 2021


This article was completed as part of the requirements for the Rhine Education Center course entitled A Skeptical Approach to Parapsychology. It provides a critical evaluation of Dr. Karlis Osis’s article entitled “Characteristics of Purposeful Action in an Apparition Case” which was published in The Journal of the American Society for Psychical Research, volume 80, in 1986. The purpose of this article is to provide a truly skeptical perspective.

Keywords: parapsychology, post-mortem apparition, apparition, extrasensory perception


A Critical Review of Dr. Karlis Osis’s “Leslie” Apparitional Case

Historical Background

In April of 1986, The Journal of the American Society for Psychical Research published a single case study entitled “Characteristics of Purposeful Action in an Apparition Case” written and researched by parapsychologist Dr. Karlis Osis. In his article, pseudonyms are used for each individual. “Constance” brought these apparitional experiences (AEs) to Dr. Osis’s attention when she rejoined the American Society for Psychic Research (ASPR) in early 1983. She played a part in the AEs as detailed below.

On a Wednesday in 1982 at 11:30 p.m., a 36-year-old father and business man named “Leslie” was unexpectedly killed while piloting a private aircraft across the southern portion of the United States. Eighteen months prior to his death, his 1 ½ year old son “Ricky” had drowned. He had taken up flying as an outlet for his mental anguish.

Early Thursday morning, “Vivian”, who was married to one of Leslie’s cousins, told her mother, Constance, that Leslie had died in a plane crash. Constance had only ever met Leslie once at Vivian’s wedding. Constance had not seen Leslie’s mother “Marge” except on several occasions, 13 years prior to Leslie’s death. Constance informed the researchers that she may have had a precognitive dream the day before Leslie’s plane crash. In her dream, Constance saw a plane coming down and heading toward her. She had made a note of it on her calendar.

Vivian asked Constance to pray for Leslie because “she thought, he died suddenly, unprepared, and he might be confused” (Osis, 1986, pp. 180). As a result of the tragic news and her possible precognitive dream, Constance felt compelled to do more. She found a photograph of Leslie in her daughter’s wedding album and began talking to him as if he was in front of her. Constance had suggested to Leslie that it would be comforting to his mother if he would find his little boy who had drowned, take him by the hand, and appear before her (Osis, 1986, pp. 180).

Leslie’s discarnate spirit reportedly obliged by making an appearance before Marge and his 6-year-old niece “Jennifer” on separate occasions and at different locations. Constance did not know Jennifer nor her parents. Two nights after Constance had suggested Leslie appear to his mother, he did. Marge told the researchers the following information:

There he was, Leslie, with the baby, and he was holding the baby’s hand … they were at the foot of the bed. They looked at each other. I was wide awake then. They were content; they were happy that they found each other, that they were together now. And they were letting me know that it is so; I got that feeling. (Osis, 1986, p. 181)

Vivian called Constance six days after Leslie’s funeral to inform her of Marge’s AE.

A couple of hours prior to Marge’s AE, Leslie had made an apparitional appearance to his 6-year-old niece Jennifer. Jennifer was aware of her Uncle Leslie’s death. She was fond of her uncle because he would visit often and she would play with his children. He would also take her flying on occasion. Dr. Osis describes Jennifer as being “a frail and sensitive child. Jennifer was raised in an atmosphere of appreciate for Eastern culture and beliefs, her parents having made repeatedly long stays in India, where they acquired Buddhist beliefs in afterlife and reportedly observed psychic phenomena” (Osis, 1986, p. 178). With respect to her AE, Jennifer stated: “I was up and awake when I saw like a cloud in my room and there was [sic] Leslie and Ricky holding hands … They looked just regular [life-like] … It looked almost exactly like him [Leslie]” (Osis, 1986, p. 182). Jennifer became aware of Marge’s experience approximately a day or so after her own experience, whereas Marge wasn’t aware of Jennifer’s experience for at least a month (Osis, 1986, p. 183).

Critical Analysis

Single Case Studies

This is a single post occurrence case study analysis of a spontaneous AE. Notwithstanding, the research was conducted outside of a laboratory environment which means that rigorous methodological procedures and guidelines were not in place. This has been identified as problematic when researching case studies (Yin, 2009, pp. 14-15). Albeit, working outside of a laboratory is a reality when it comes to apparitional research. Other issues which have been identified with single case studies include issues with reliability, replicability, external validity and generalisability (Willis, 2014, pp. 4-5). Unfortunately, AEs are difficult to validate and replicate in general as they occur at their own volition. One’s colleagues are limited when it comes to conducting an independent review and replication of the type of data collected with spontaneous AEs. The detail involved in the researcher’s generalization also becomes limited when an event is a single occurrence.

Memory and Recall

The core of this study, relies entirely on the memory and human experience of three independent individuals (with some corroboration from other individuals who did not witness the experience first-hand), and where subjectivity may have been involved. Dr. Osis acknowledges this by stating “these events depend solely on the memories of the experients and those in whom they confided” (Osis, 1986, p. 185). As a retired Royal Canadian Mounted Police officer of 15 years and a professional court witness, I am aware through lived experience that a plethora of issues surrounding ones memory, recall, external influences, biases, and difference in perception exist. Especially during highly stressful or spontaneous events. Dr. Osis notes that none of the three experients kept any written records detailing their experiences (Osis, 1986, p. 184). Therefore, all of the testimony collected relies solely on memory recall.

Dr. Osis highlights an important issue with regard to eliciting information from children, especially since this case study relies partly on the testimony of 6-year-old Jennifer. He states:

Additional reservation is usually called for when one obtains anecdotal material from children. This must have come to the reader’s mind when learning that one of the principal experients was a 6 year old, despite the fact that she told her parents of the event just after it occurred. (Osis, 1986, p. 185)

Speaking again from lived experience as a former police officer, investigators must be diligent in how they retrieve information from children. In Canada, police are required to have a special interviewing course which teaches investigators special interviewing techniques so that no leading information is gleaned and only the purest version of events are obtained.

Jennifer’s situation is further complicated by the fact that there are socio-cultural factors at play in her environment. Her parents are believers in the paranormal whom openly talk about life after death matters. This could have influenced Jennifer and created a bias. When one takes into consideration these facts, in addition to whether or not Dr. Osis conducted a proper child interview, and issues surrounding the degradation of memory over time, one should be extremely cautious of Jennifer’s testimony. Not because she is fabricating information, but because her perception of the experience may have been misunderstood by researchers or influenced by biases.

The AE undoubtedly had a lot of emotions involved for the experients. Marge, a distraught and grieving mother, witnessed the apparition of her deceased son and grandson. Jennifer, a vulnerable child, witnessed the apparition of her deceased uncle and cousin. Harvey et al. (2014) cautions that emotion can bias memory (p. 161).

Dr. Osis (1986) states that the witnesses were interviewed over the telephone on a number of occasions. “The initial interviews were conducted in early 1983. Re-interviewing was done in late 1984; this produced some new information which was not available in the preliminary report” (p. 176). Dr. Osis eventually conducted an in-person interview with one of the experients (Marge). Marge estimated that her AE lasted approximately 15 seconds, whereas Jennifer was unsure of the duration (Osis, 1986, pp. 181-182). Furthermore, Dr. Osis conducted a follow up interview with Marge 2 ½ years after the AE occurred. I shall provide a forewarning with respect to human memory.

Cognitive psychologists have demonstrated that people’s recall of everyday events can be highly inaccurate. Human memory is not a device permitting literal replay of previously experienced incidents. Once a particular interpretation is placed on an event, features of the experience consistent with that interpretation might be recalled but inconsistent features will tend to be forgotten. (Irwin & Watt, 2007, p. 40)

Memory is a neuroplastic process in which the brain stores and retrieves changes that occur in response to experiences (Pinel & Barnes, 2018, p. 272). When Marge and Jennifer experienced their apparitional sighting, their short-term memory would have been activated which is believed to be able to record information for 20 to 30 seconds (Cherry & Block, 2019). Once the experience was no longer the focus of their attention, their experiences would have been encoded in their long-term memory (Pinel & Barnes, 2018, p. 521). Whereas Marge and Jennifer were able to recall their experience some time afterward during Dr. Osis’s re-interview, they were likely retrieving their memories from their conscious explicit memory, specifically their episodic memories (Pinel & Barnes, 2018, p. 123). Episodic memories stem from particular events or “episodes” in one’s life (Pinel & Barnes, 2018, p. 277). However, memory is susceptible to natural decay over time and can sometimes fail to encode information which in turn can result in recall difficulties (Cherry & Block, 2019, n.p.).

Belief in the Paranormal

Belief in the paranormal is a contentious topic that often arises when dealing with human experience. Parapsychologists have discovered the sheep-goat effect when conducting extrasensory perception (ESP) testing in laboratories. Believers (sheep) have been shown to score higher than non-believers (goats). Paranormal belief may also sometimes account for an individual’s misinterpretation of normal events. Gullibility is a psychological characteristic that has been shown to be correlated to believers of the paranormal. Humans are also prone to being “primed” which is when one is supplied with information which may influence their perception of a situation, task or location. For instance, when participants are told that the researchers have a skeptical belief in the paranormal, they tend to be reluctant to fully acknowledge their paranormal beliefs (Irwin & Watt, 2017, pp. 222-223).

With respect to the experients in this case study, Marge had no belief in the afterlife until after her AE, whereas Constance believed in the afterlife and anomalous phenomena. As for Jennifer, she was brought up in a socio-cultural environment of belief in the afterlife, reincarnation and psychical experiences. Jennifer’s mother told researchers that it would not be outside the range of expectations that Jennifer witnessed an AE because they believe in reincarnation and the family often discusses topics in relation to survival (Osis, 1986, p. 183). “The form of paranormal beliefs held by a given person is strongly influenced by cultural factors such as socialization within the family…” (Irwin & Watt, 2017, p. 224). In this instance, there is a correlation between Jennifer’s upbringing and her belief in the paranormal which could have impacted her AE.

Survival-of-personality or Super-ESP

Dr. Osis presents three psi-related hypothesis with respect to this case study. They are: survival-of-personality model, survival-of-fragments model, and Super-ESP. Survival-of-personality assumes that the AEs occurred as a result of Leslie and Ricky being deceased agents who actively participated in the experience (Osis, 1986, p. 186). The survival-of-fragments model “proposes that only fragmented images or thought, which were generated when the appearer was alive, are all that survive death” (Osis, 1986, p. 186). Super-ESP is the belief that the AEs were projections as a result of living agents involved to wit: Constance, Marge, and Jennifer (Osis, 1986, p. 186).

Dr. Osis highlights the work of other parapsychological researchers who believe in the plausibility of making an arrangement with a discarnate entity:

Gauld (1982), Hart (1959), Richmond (1938), and others have pointed out data that strongly suggest communications arranged in such a fashion. Nea Walker (1935) described how she requested a communicator to come to a specified mediumistic sitting days later, and, although the medium was not informed of the “appointment” the ostensible spirit seemed to comply and communicate. (Osis, 1986, pp. 187-189)

Dr. Osis discusses the possibility of Constance communicating with Leslie through telepathy whereas she had requested he appear before his mother. This would be possible whether the survival-of-personality or Super-ESP theories are correct. Although Dr. Osis felt that the Super-ESP theory becomes too strained and complex when applied to his case study, I believe that the Super-ESP theory is still a possibility for these AEs. Some forms of extrasensory perception are extremely difficult to classify.

Consider an example. From time to time I find myself thinking I have not heard from one of my professional colleagues for a while, and later the same day I receive a letter from that person. Perhaps this may be deemed to entail ostensible extrasensory awareness of the letter itself, in which case my experience would be considered clairvoyant. Or the experience might be construed as apparent awareness of the perceptions of the mail sorter, that is, an instance of telepathic experience. Or again it could be represented as a precognitive experience of the subsequent mail delivery or of my opening the letter, or perhaps even a retrocognitive experience of my correspondent writing the letter some weeks earlier. In practice therefore, the utility of the proposed categories of ESP may be doubtful. Much the same could be said for their application to the description of laboratory data. Thus it was felt necessary to devise the expression of general extrasensory perception (GESP) to refer to data that could have reflected unknown components of clairvoyance or telepathy or both. (Irwin & Watt, 2017, p. 5)

In this particular case study, the AEs commenced when Constance began picturing Leslie in her mind “as if I was talking to him and he was right there” (Osis, 1986, p. 180). Jennifer also makes an interesting comment to Dr. Osis when asked how the apparitions disappeared. She told him, “I stopped thinking about them and they went away” (Osis, 1986, p. 182). This comment is extremely fascinating as most experients report that the apparition(s) that they have witnessed simply vanish, dissipate, or walking through a particular area of a location prior to disappearing.

Irrelevant Information

It is interesting, yet puzzling, as to why Dr. Osis mentioned having three psi practitioners hold token objects in an attempt to receive impressions as to the cause of the plane crash while at the American Society for Psychic Research (ASPR) laboratory. This is known as psychometry, a type of clairvoyance in which a medium possesses the ability to receive relevant information and associations from an object (Barrington, 2016, n.p.). It is not the use of psychometry which is questionable, but the fact that he writes “Although these data were recorded and analyzed, they are not pertinent to the AEs and will not be discussed” (Osis, 1986, pp. 177).

While I agree that the mechanism of the crash is irrelevant to the fact that an apparition made an appearance before two independent witnesses, I question the relevance of why Dr. Osis would even mention this information in his article if it wasn’t pertinent. I appreciate the full, fair and frank disclosure process, however, this leaves the reader left wondering whether the psi practitioners had any hits (success) or misses while examining the token objects. This paragraph seemingly serves no meaningful purpose except to cast obscurity.

Sleep-Wake Disorders

It is rather surprising that Dr. Osis didn’t consider or eliminate any medical and/or psychological conditions as a potential cause for the AEs. Specifically, any possible sleep-wake disorders. Generally, sleep paralysis is a medical condition in which elements of wakefulness and rapid eye movement (REM) sleep become intertwined. Sleep paralysis can be accompanied by visual, auditory and textile hallucinations. It can evoke strong feelings. Another common characteristic of sleep paralysis reported by some experients include the feeling of an intruder or a presence in their room (Van Dusen, 2021, pp. 138-140).

When Marge witnessed her AE, she was asleep before she was awoken by a “disturbance in her room” (Osis, 1986, p. 181). The second experient, Jennifer, reported that when she witnessed her AE, she was awake and meditating. Her family holds Buddhist beliefs, one of which is the importance of meditating.

In some modern formulations, the goal of meditation has expanded beyond relation and decreased arousal to include a state of consciousness that is deliberately half-asleep, a “physiological twilight condition between waking and sleep,” equivalent to sleep, or a form of sleep-like hibernation a “shallow torpor” that is reversed by (i.e., opposite of wakefulness). (Britton et al., 2013, pp. 64-65)

A paragraph regarding what steps were taken to rule out a sleep-wake disorder would have been more fruitful than the futile paragraph regarding the psi practitioners attempt at psychometry.

Upon review of Dr. Osis’s article, I discovered an inconsistency in Marge’s description of Leslie and Riley. Initially Dr. Osis’s writes, assumingely, in Marge’s own words:

They were solid. There was like grayness around, like a gray cloud around them. I would say there was a mist in the whole room, nothing you could touch, just the grayness all around. But they were solid, both of them. The room was dark; electric light was coming from outside through the venetian blinds…. But I didn’t need light to see them. There is a lot of traffic around my area. No matter at what time you got trucks and buses. Not one sound then, all was excluded at that moment, everything, as though the world had stood still. And there was nobody but us three in the world. (Osis, 1986, p. 181)

Later on, Dr. Osis writes:

How does Marge’s description of the apparition of Leslie and Ricky fit the test findings? The exclusion of traffic noises and the reduction in clarity of her visual surrounds, for example, “like a gray cloud around them,” go well with her above-average ability to become absorbed in her experiences. In regard to vividness, she said that the apparitions were “like shadows,” which is far from what would be expected of someone who is constructing apparitions with an imagination as vivid as hers. (Osis, 1986, p. 184)

Nowhere in Dr. Osis’s article does Marge describe Leslie and Riley “like shadows”. The words are in quotes in Dr. Osis’s article and read as though Marge had said it. It is possible Dr. Osis was referring to his hand written notes or made his own interpretation that the “gray cloud around them” made them appear as shadows. Either way, it is an inconsistent description which stood out. The description of shadow like figures and the highlighted information surrounding the reduction of otherwise consistent traffic noises also lends credence to the sleep-paralysis hypothesis. Shadow figures are a common hallucination seen during sleep paralysis. The noise reduction in the room could also be attributed to a sleep-wake disorder. Sleep spindles are rhythms in the brain capable of influencing external stimuli while we sleep. “If spindles hinder the transmission of external stimuli from the thalamus to the cortex, a higher rate of spindle production throughout the night would be expected to preserve sleep stability in the face of noise” (Dang-Vu, 2010, p. 626). In other words, sleep spindles allows us to block out noises in the environment so we do not interrupt our sleep state.

Rarity of Double Apparitional Cases

Dr. Osis discusses three points on how this case study is a rarity. First, double apparitions are rare outside of near-death experiences when two individuals have died separately. Second, it is rare for double apparitions to appear in different locations and in the same pose. Lastly, he references the rarity in responding to an apparition with soothing and beneficial feelings, and that it is infrequent outside of near-death experiences (Osis, 1986, p. 186). I concur with Dr. Osis’s second point as being rare. I have never investigated double apparitions whom have died separately and seemingly appear at multiple locations in the same pose. However, I have personally investigated a double apparition case where calming feelings were perceived by the experient.

A Canadian Department of National Defence civilian security guard had been arrested during a domestic dispute on July 18, 2005. She was taken to the Elgin-Middlesex Detention Centre in London, Ontario. At 5:55 a.m., she was awake in her jail cell when a correctional officer came through the cell block and began rousing the prisoners. As he walked past each cell, he clanged a tin cup against the steel bars. He was asking if any of the prisoners wanted a cup of coffee. The client sat up quickly after she felt someone touch her shoulder. It felt like a little tiny hand touching her. As she turned her head toward whatever was touching her, she saw a little hand resting upon her shoulder. She heard a voice say “You are going to be okay mom.” As she continued to turn, she saw a full apparition of whom she believed to be her daughter. Her daughter had passed away 19 years previous as a stillborn on August 29, 1986 at 11:11 a.m. Her daughter was being held by another man whom she described as looking similar to Jesus. She would later find out from her mother that the description matched that of her other, older brother who had passed away. Her brother stood silently in the jail cell smiling at her. This experience brought the client a sense of peace in what can only imaginably be a dark time in her life. Fortunately, there was a happy ending for the client. The prosecution did not have any evidence to proceed to trial and the charges against her were withdrawn. She is no longer in an abusive relationship and spends her time advocating against domestic violence and promoting equal parenting rights (Van Dusen, 2021, pp. 56-60).

Environmental and Natural Occurring Phenomena

Dr. Osis makes no mention whatsoever of making inquiries regarding any potential environmental or natural occurring phenomena which may have attributed to the AEs. To his defence, these AEs occurred in 1982 and weren’t investigated by Dr. Osis until early 1983 which even predates the release of the blockbuster movie Ghostbusters,released in the summer of 1984. Therefore, he was lacking some knowledge that modern parapsychologists now know. For instance, that magnetic fields can cause humans to experience fear and see apparitions, and that unusual experiences correlate significantly with environmental factors such as magnetic fields and lighting levels (Persinger et al., 2000, pp. 659-674; Wiseman et al., 2003, pp. 191-211).

However, there were some environmental and natural occurring phenomena already known to parapsychologists in 1983 that cause haunting-like characteristics in which he neglected commentary on within his article. Dr. Osis had access to very sophisticated equipment that most parapsychological investigators of the time did not. He was familiar with “strain-gauge plates to detect minute stresses and vibrations, such as footsteps as the apparition walks down a hallway … and infrared cells to detect a presence” (Auerbach, 2016, p. 274). He was using this type of equipment in his parapsychological research in 1980, three years prior to these AEs occurring (Blackmore, 1983, n.p.). However, there was no mention of any investigatory inquiry using equipment in an attempt to rule out natural occurring causes in this case study.

Hallucinatory explanations were also known to parapsychologists during Dr. Osis’s era. In fact, some argue that AEs are hallucinatory by nature, separate from mirages and perceptual illusions (Irwin & Watt, 2007, p. 193). Anderson and Anderson (1982) discuss knowledge of drugs and mental illnesses causing AE hallucinatory visions which existed during Dr. Osis’s time. (as cited in Irwin & Watt, 2007, p. 193). Dr. Osis does consider the possibility that Marge and Jennifer had a hallucination, but does highlight the difficulty in believing that they both hallucinated the two same decedents at different times and in separate locations. However, Williams (2015) highlights the fact that Marge was deeply grieved at the time of Leslie’s death:

(having recently lost both Leslie and her grandson), and it is quite possible that there was a strong personal motivation for her to want to see Leslie and her grandson again. Such a state of mind could have predisposed her to seeing a hallucinatory vision of them. (pp. 13-14)

Throughout his article, he doesn’t articulate any steps taken to rule out any medical or psychological conditions of the experients per say, even though he had prior experience pertaining to these matters. Dr. Osis & Dr. Haraldsson (1961; 1977) had extensive experience investigating deathbed visions in which the patient’s experiences weren’t attributed to “medication, sedation, high fever, delirium, and ill symptoms” (as cited in Williams, 2015, p. 4; Williams et al., 2010, p. 4). As discussed earlier, Dr. Osis also fails to discuss sleep-wake disorders such as sleep paralysis, hypnagogia and hypnopompia which were also known during his time.

Dr. Osis did administer some psychological tests, in which Marge scored the highest extreme on vividness of imagery and ability to become immersed in an experience. Williams et al. (2010) clearly suggests that Marge has such a capacity for imagination, fantasy and absorption that she can mentally immerse herself so deeply within an experience, that she can block out external stimuli occurring around her as described during her experience with the reported auditory distortion (p. 15).

Chance Coincidence

Dr. Osis himself advises that one cannot rule out chance coincidence in this case study. He states “chance coincident can never be totally excluded, but, in my estimation, the likelihood of it explaining this case is exceedingly small” (Osis, 1986, p. 186). Exceedingly small, but not impossible.


This article was written from a skeptical perspective. Overall, Dr. Osis did a thorough investigation of these spontaneous AEs given the knowledge which existed during his time period. The biggest criticism pertaining to his article would be the lack of a skeptical approach toward an attempt to truly understand and explain the AE experiences of Marge and Jennifer. Parapsychology is an ever evolving social science. There still remains many unknowns in this discipline. Dr. Osis summarizes this fact in his conclusion. “Let us remember that we operate in the domain of a very young science in which many uncertainties still prevail: One case alone cannot decide the survival issue” (Osis, 1986, p. 191). Thirty-five years later, this statement still holds validity. The mystery surrounding whether or not human consciousness can survive beyond clinical death remains hidden behind that dark veil of death.



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