2018 Was a Year to Forget. Really.

Our memory for the details of real-life events is poor, according to a recent study.

Seven MIT students took a one hour walk through Cambridge, MA. A day later, they were presented with one second video clips they may or may not have seen during their walk (the “foils” were taken from another person's recording). Mean recognition accuracy was 55.7%, barely better than guessing.¹

Minimal recognition memory for detailed events. Dashed line is chance performance. Adapted from Fig. 2 of Misra et al. (2018).


How did the researchers capture the details of what was seen during each person's stroll about town (2.1 miles / 3.5 km)? They were fitted with eye tracking glasses to follow their eye movements (because you can't remember what you don't see), and a GoPro camera was mounted on a helmet.

from Fig. 1 (Misra et al., 2018).

One problem with this setup, however, was that the eye tracking data had to be excluded. The overwhelmingly bright summer sun prevented the eye tracker from obtaining accurate images of the pupil. Thus, Experiment 2 was performed inside the Boston Museum of Fine Arts with a separate group of 10 students.

from Fig. 1 (Misra et al., 2018).

Recognition performance was better in Experiment 2. Mean accuracy was 63.2% — well above chance (p=.0005) — but still not great. Participants correctly identified clips they had seen 59% of the time, and correctly rejected clips they hadn't seen 67% of the time. One participant (#4) was really good, and you'll notice the individual differences below.

Dashed line is chance performance. Adapted from Fig. 2 of Misra et al. (2018).

In Exp. 2, the investigators were able to look at the influence of eye fixations on memory performance. Not surprisingly, people were better at remembering what they looked at (fixated on), but this only held for certain categories of items: talking people, objects rated as “distinctive” (but not distinctive faces), and paintings (but not sculptures).

Fig. 4 (Misra et al., 2018).

How do the authors interpret this finding? We don't necessarily pay attention to everything we look at.

“What subjects fixated on also correlated with performance (Fig. 4), but it is clear that subjects did not remember everything that they laid eyes on. There is extensive literature showing that subjects may not pay attention or be conscious of what they are fixating on. Therefore, it is quite likely that, in several instances, subjects may have fixated on an object without necessarily paying attention to that object. Additionally, attention is correlated with the encoding of events into memory. Thus, the current results are consistent with the notion that eye fixations correlate with episodic memory but they are neither necessary nor sufficient for successful episodic memory formation.”

For me personally, 2018 was a year to forget.² Yet, certain tragic images are etched into my mind, cropping up at inopportune times to traumatize me all over again. That's a very different topic for another time and place.


May your 2019 brighten the sky.

The number 2019 is written in the air with a sparkler near a tourist camp outside Krasnoyarsk, Russia, on January 1, 2019. (The Atlantic)


Footnotes

¹ However:

“Two subjects from Experiment I were excluded from the analyses. One of these subjects had a score of 96%, which was well above the performance of any of the other subjects (Figure 2). The weather conditions on the day of the walk for this subject were substantially different, and this subject could thus easily recognize his own video clips purely from assessing the weather conditions. Another subject was excluded 260 because he responded 'yes' >90% of the trials.”

² See:

I should have done this by now...

The Lie of Precision Medicine

Derealization / Dying

There Is a Giant Hole Where My Heart Used To Be

How to Reconstruct Your Life After a Major Loss


Reference

Misra P, Marconi A, Peterson M, Kreiman G. (2018). Minimal memory for details in real life events. Sci Rep. 8(1):16701.

We forget most of our lives... Misra et al, Scientific Reports 2018. https://t.co/iK3E6c8mvB pic.twitter.com/ern3QQVWJm

— Gabriel Kreiman (@gkreiman) November 16, 2018

Folie à deux and Homicide for the Holidays

Nothing says home for the holidays like a series of murders committed by family members with a shared delusion. So sit back, sip your hot apple cider or spiked egg nog, and revel in family dysfunction worse than your own.

{Well! There is an actual TV show called Homicide for the Holidays, which I did not know. Kind of makes my title seem derivative... but it was coincidental.}


“Folie à deux”, or Shared Psychotic Disorder, was a diagnosis in DSM-IV-TR:

(A) A delusion develops in an individual in the context of a close relationship with another person(s), who has an already-established delusion. 

(B) The delusion is similar in content to that of the person who already has the established delusion. 

(C) The disturbance is not better accounted for by another Psychotic Disorder (e.g., Schizophrenia) or a Mood Disorder With Psychotic Features and is not due to the direct physiological effects of a substance (e.g., a drug of abuse, a medication) or a general medical condition.

Folie à deux occurs in the secondary partner, who shares a delusion with the primary partner (diagnosed with schizophrenia, delusional disorder, or psychotic depression). In in DSM-5, folie à deux no longer exists as a specific disorder. Instead, the secondary partner is given a diagnosis of “other specified schizophrenia spectrum and other psychotic disorder” with a specifier: “delusional symptoms in the partner of individual with delusional disorder” (APA, 2013).

The first cases were reported in the 19th century by the French psychiatrists Baillarger (1860) and Lasègue & Falret (1877). The latter authors note that insanity isn't contagious, but under special circumstances...

a) In the “folie à deux” one individual is the active element; being more intelligent than the other he creates the delusion and gradually imposes it upon the second one who is the passive element. At the beginning the latter resists but later, little by little, he suffers the pressure of his associate, although at the some degree he also reacts and influences the former to correct, modify, and coordinate the delusion that then becomes their common delusion, to be repeated to all in an almost identical fashion and with the same words.

The two individuals are in a close relationship and typically live in an isolated environment.

A recent paper by Guivarch et al. (2018) covered the history of the disorder, and performed a literature review on folie à deux and homicide. They found 17 articles:

In the cases examined, homicides were committed with great violence, usually against a victim in the family circle, and were sometimes followed by suicide. The main risk factor for homicide was the combination of mystical and persecutory delusions. The homicides occurred in response to destabilization of the delusional dyads.

Body mutilation is not uncommon: “These features appear in the reported case of a mother who was delusional and killed her young son by hitting him on the head 3 times with a hatchet.”

The authors presented a detailed history of induced psychosis involving Mr. A (the secondary) and Mrs. A (the primary, who had a family history of delusion). Shortly after getting married, they had a child who was removed by social services due to inadequate parenting.

Subsequently, the couple engaged in several years of delusional wandering in France and Italy, traveling from village to village to accomplish “a divine mission”, during which time they were hosted in monasteries or abbeys. They expressed delusional feelings but never visited a psychiatrist and were never confronted by the police. The couple's relationship transformed; the partners stopped having sexual relations and quickly established a delusional hierarchical relation, with Mrs. A being called “Your Majesty” and Mr. A considering himself “King of Australia, Secretary of Her Majesty”.

After about 20 years of this, in a fit of overkill, Mr. A murdered a random 11 year old child by inflicting 44 stab wounds. Earlier, he had felt humiliated and persecuted at a police check point, which provoked an “incident.” The murder of the child was part of their delusional divine mission, to make a necessary sacrifice that would restore balance.


Paranoia of the exalted type in a setting of folie à deux

The famous case of Pauline P (“a dark, rather sulky looking but not unattractive girl of stocky build”) and Juliet H (“a tall, willowy, frail, attractive blonde with large blue eyes”) was also mentioned (Medlicott, 1955). The two girls established a very close bond, constructed an elaborate make-believe world of fictional characters, withdrew from all others, became sexually involved, and developed a superiority complex. They killed Pauline's mother “because one of the girls was going to move with her parents, which would have led to the separation of the delusional dyad (Medlicott, 1955).” This formed the basis of the fantastic 1994 film, Heavenly Creatures, featuring Melanie Lynskey and Kate Winslet.

Granted, their indissoluble bond was pathological, but laughable 1955 views of same-sex relationships were on display in this analysis:

There is of course no doubt that the relationship between these two girls was basically homosexual in nature. Pauline made attempts in 1953 of establishing heterosexual relationships, but in spite of intercourse on one occasion there was no evidence of real erotic involvement. All her escapades were fully discussed with Juliet which is a common feature amongst people basically homosexual in orientation.

Yes, we can generalize and say that all teenage girls in the 1950s commonly bragged about their heterosexual exploits with their lesbian lovers.

From Pauline's 1953 diary:

“To-day Juliet and I found the key to the 4th World.  ... We have an extra part of our brain which can appreciate the 4th World. Only about 10 people have it. When we die we will go to the 4th World, but meanwhile on two days every year we may use the key and look in to that beautiful world which we have been lucky enough to be allowed to know of, on this Day of Finding the Key to the Way through the Clouds.”

Your family gatherings may not always be harmonious, but presumably your delusional children are not plotting to kill you. Happy Holidays.

National Lampoon's Christmas Vacation

References

Baillarger J. (1860). Quelques exemples de folie communiquée. Gazette Des Hôpitaux Civils et Militaires 38: 149-151.

Guivarch J, Piercecchi-Marti MD, Poinso F. (2018). Folie à deux and homicide: Literature review and study of a complex clinical case. International Journal of Law and Psychiatry 61:30-39.

Lasègue C, Falret J. (1877). La folie à deux (ou folie communiquée). Annales Médico Psychologiques 18: 321-355. English translation (Dialogues in Philosophy, Mental and Neuro Sciences, December 2016).

Medlicott R. (1955). Paranoia of the exalted type in a setting of folie à deux; a study of two adolescent homicides. The British journal of medical psychology 28:205-223.