Could confinement foster the emergence of traumatic or psychotic symptoms?

doi:10.1684/nrp.2021.0640

Rev Neuropsychol

2020 ; 12 (S1) : 75-81

Could confinement foster

the emergence of traumatic or psychotic symptoms? ^*

Le confinement peut-il favoriser l’émergence de symptômes

traumatiques ou psychotiques ?

Mélissa C. Allé^1,2, Fabrice Berna^2,3,4, Pierre Vidailhet^2,3,5,

Anne Giersch^2,3,4, Amaury C. Mengin^2,3,5

1Université de Aarhus, Danemark

2Inserm U1114, Strasbourg, France

3Université de Strasbourg,

Hôpitaux universitaires de Strasbourg, 1 place de l’Hôpital, 67091 Strasbourg cedex, France

4Fondation FondaMental

5Centre Régional Psychotrauma Grand Est

<amaury.mengin@chru-strasbourg.fr>

To cite this article: Allé MC, Berna F, Vidailhet P, Giersch A, Mengin AC.

Could confinement foster the emergence of traumatic or psychotic symptoms?

Rev Neuropsychol 2020;12(S1):75-81 doi:10.1684/nrp.2021.0640

Abstract The ongoing pandemic has led a large proportion of the global population to confine and socially isolate themselves for several weeks. The main psychological consequences of quarantine have previously been described in the literature: depression, stress, anxiety, and sleep disorders. Symptoms of post-traumatic stress disorder have also been described as a consequence of periods of confi- nement, but their emergence is the subject of debate, and the very nature of confinement raises questions about its traumatic potential. We will first study the “confinement event”

and how it may or may not lead to symptoms of post-traumatic stress disorder. On another note, although many studies have described the emergence of psychotic symptoms in various contexts of social isolation or sensory deprivation, no study on the psychological effects of confinement has explored these symptoms in the context of a health crisis such as the one we are currently experiencing. In this article, we discuss the eventuality of experiencing psy- chotic symptoms during confinement. Finally, we conclude by counterbalancing the negative effects of confinement by presenting some psychotherapies that use confinement and social isolation as therapeutic tools.

Key words: lockdown·^confinement·^quarantine·social isolation·post-traumatic stress symptoms (PTSD)·psychotic symptoms

T

Such a global lockdown of population is unprece- dented in our history and challenges the deeply social nature of man[1].

Because of its exceptional and unprecedented nature, the consequences of such an experience in the short and long-term are unknown. However, very shortly after the crisis onset, many physicians and scientists have taken

∗This article is an English language translation of the following article:

Giffard B, Joly F. Impact psychologique de l’épidémie de Covid-19 et du confinement chez des patients pris en charge pour un cancer.Rev Neuropsychol2020 ; 12 (2) : 193-5. doi:10.1684/nrp.2020.0569.

Correspondence:

A.C. Mengin

up these issues in order to better understand the effects of lockdown on mental health populations to be able to anticipate similar situations in the future.

Psychological consequences are already numerous and include symptoms of stress, anxiety, mood and sleep dis- orders[2, 3]. As expected, the situation of lockdown and social isolation causes an increase in depressive [3] and anxious symptoms[4]in vulnerable people but these symp- toms, accompanied of sleep disorders, also occurred in people with no psychiatric history[4, 5]. In addition, the literature on the psychological impact of a health crisis accompanied by population lockdown often mentions the emergence of short and long-term post-traumatic stress symptoms. We will discuss the emergence of post-traumatic stress symptoms under these conditions in the first part of our work.

In parallel, the literature on psychological consequences of lockdown during a sanitary crisis rarely embraces the problem of psychotic disorders or symptoms. At the moment, no data has been collected or reported on this theme in the literature, whereas many studies describe the emergence of psychotic symptoms in a wide variety of con- texts of social isolation or sensory deprivation: solitude, extreme conditions of prison detention, polar or subma- rine expeditions, space travels, military situations, or even isolation of patients under intensive care. Based on these observations, we will discuss the links between lockdown with social isolation and psychotic symptoms in the second part.

Are lockdown and social isolation vectors of traumatic symptoms?

The DSM-5 indicates that a potentially traumatic event must necessarily confront the individual to a risk of immi- nent death or serious injury, or sexual violence, to be the source of a Post-Traumatic Stress Disorder (PTSD) (DSM-5 Criteria A)[6]. In addition, PTSD usually involves intrusive distressing memories related to specific sensory features (hearing a bomb or a gunshot, feeling the hand of an aggressor, smelling blood, etc.). During lockdown, the indi- vidual finds himself in a closed, confined environment with few obvious violent sensory elements, “protected” from an external threat by the isolation. One could therefore expect to find no PTSD as a consequence of lockdown[3]. How- ever, the literature on social isolation or consequences of previous lockdowns in epidemic contexts (SARS, H1N1) connect lockdown with PTSD. Based on this literature, we will see how to explain the post-traumatic symptoms related to the population lockdown in the context of the COVID-19 pandemic and will make proposals to prevent it.

The clues of post-traumatic symptoms related to lockdown

Lockdown is a synonym of confinement, that derives from the verb to confine: “To force someone to stay in a limited space”. It involves a form of social isolation, which corresponds to a “physical separation” from other individ- uals for a certain duration [7]. Several studies suggested that this isolation could promote the onset of post-traumatic symptoms. First, prolonged social isolation was used as a PTSD animal model in mice, placed in individual cages for 3 to 4 weeks. The mice then showed behavioral disorders such as exaggerated fear reactions (hyperarousal), aggres- siveness or impulsivity that may be encountered in human PTSD (DSM-5 Criterion E) [6]. Some situations of forced social isolation outside the epidemic context exist in human beings. It is the case of prisoners placed in solitary confine- ment, i.e. isolated from the rest of the group as a punishment method. These practices were shown to provoke negative psychological effects such as depression, suicidal ideation,

irritability[7]. In a cohort of 119 recently released prison- ers, investigators found symptoms of PTSD more frequently in participants who experienced solitary confinement in the course of their last incarceration (43% vs. 16%)[8]. In pre- vious epidemic episodes, lockdown measures had already been taken. After the 2003 SARS epidemic, 29% of moder- ate to severe post-traumatic stress symptoms were found in a sample of 129 people living in Toronto immediately after confinement [9]. Higher levels of PTSD symptoms were found among hospital staff who had been confined (as com- pared to those who had not), up to 3 years after the SARS episode[10]. About H1N1 epidemic, a PTSD was present in 30% of confined children and 25% of their parents during the lockdown period[11]. Finally, concerning the ongoing episode of COVID-19, 54% of participants from the con- fined Chinese population (interviewed at the end of January, which corresponds to the beginning of lockdown in China) had a score of Impact of Event Scale-Revised (IES-R) greater than 24, considered by Wang et al.[4] as a “moderate to strong impact of the health crisis”. And it so happens that the IES-R includes many trauma-related symptoms (e.g., flash- backs, avoidance, hyperarousal, irritability). First, we have seen that lockdown was not similar to a “typical” potentially traumatic event. Yet, social isolation was used as a PTSD model in animals and promoted PTSD in isolated prisoners or in confined populations during the COVID-19 and earlier epidemic situations. How can we explain the emergence of such symptoms during lockdown?

Lockdown in the context of a pandemic:

a potentially traumatic event?

While social isolation animal models and the solitary confinement of prisoners share similarities with COVID- 19 lockdown it appears necessary to take into account a set of explanatory co-factors to understand the causes of post-traumatic symptoms related to COVID-19 lockdown.

Indeed, being isolated from the others represents only one aspect of all the sudden changes caused by the pandemic.

We will detail potentially traumatic elements related to the COVID-19 pandemic.

The corollaries of lockdown:

loss of resources and life rhythms, isolation, risk of violence

A relevant model to assess the risk of PTSD in the context of confinement is the resource loss model, which postulates that PTSD emerges when an individual or a group resources are threatened. These resources can be material (savings, goods), as well as social (employment, access to education, relationships) or even personal values (trust, dignity). This model has already been used for situations of isolated pris- oners[12] and in events such as the World Trade Center terrorist attacks, indicating a correlation between resource loss and the risk of PTSD[13]. Indeed, lockdown during the Covid-19 pandemic lead to important resources loss for

most of the population (loss of employment and/or income, reduced social contacts, but also a decline in confidence in the future and freedom limitations - values loss). Consistent with this model, social contact loss induced by lockdown reduces the opportunities of receiving social support, the latter being a strong predictive factor of resilience to PTSD.

However, while subjects living alone may suffer more from lockdown, the latter can also lead to a loss of intimacy and even an increase in violence in insecure families. Indeed, in France, in mid-April, police calls to inform of domestic violence increased by 30% since the beginning of lock- down[2]. These aggressions constitute potentially traumatic events as a collateral effect of lockdown, representing a risk factor of PTSD increase during and following the lockdown period. Finally, lockdown leads to a loss of life rhythms (e.g., wake-up and bedtime, mealtime, etc.). In addition to entering the model of resource loss, this element can lead to sleep disturbances that can be a major cause of PTSD [14]. Thus, during lockdown in China, a better sleep qual- ity with fewer early morning awakenings were predictive of reduced PTSD symptoms[15]. Sleep disorders in PTSD can also result from hyperarousal due to a feeling of perma- nent threat or cause nightmares involving memories of the traumatic event (DSM-5 Criterion E)[6].

During a lockdown, what kind of threat exists? What might be the content of intrusive distressing memories for locked down people? Here, we postulate that distressing memories related to lockdown in the context of the COVID- 19 pandemic will be mostly related to the risk of infection, an inseparable twin of lockdown, since it is the reason of its existence.

The pandemic: constant reminders of the threat, uncertainty about tomorrow

In the context of the COVID-19 pandemic, lockdown has been established worldwide, aimed at protecting the population from the risk of death represented by the virus itself. From the point of view of the real threat, it seems to have shown its effectiveness, given the decrease in the number of virus transmission following its introduction[16].

From the psychic point of view, the distance from this threat also seems to be favorable because we notice in the caregiver population the importance of the fear of being contaminated (or contaminate loved ones) and negative psychological effects resulting from the daily proximity to the COVID-19[17].

Yet, for the general population, this threat does not cease to exist and is transcribed through two main factors: pro- tective measures and mass media, largely saturated with information about coronavirus. On the one hand, protective measures (restriction of movements, wearing a mask, wash- ing hands, etc.) are constant reminders that a threat exists.

While these gestures are adapted and do reduce anxiety in times of crisis[4], an inappropriate increase and conti- nuation of these gestures such as those observed during the lockdown imposed by the SARS epidemic in 2003, can lead

to reduced social contact, fear of crowds or public spaces, work absenteeism, etc.[18]. Their continuation after the risk period constitutes a symptom of avoidance, which is one of the fundamental elements of PTSD (DSM-5 Criteria C)[6].

On the other hand, mass media are a constant reminder of an outside world that has become threatening, with the omnipresence of death, recalled by the daily counting of people dying from COVID-19 and of patients hospitalized in intensive care units. Thus, in addition to promote the occurrence ofheadline stress disorders[19]- characterized by anxiety emerging after over-consumption of information - repeated exposure to coronavirus information can promote ruminations and distressing memories about these worrying news (DSM-5 criterion B)[6]. Finally, lockdown prolonga- tion, regular changes and uncertainties about tomorrow are factors that can lead to negative thoughts about oneself and the world (e.g., “I can’t get out of it”, “The world is ruined”, etc.) or persistent negative emotional states (fear, anxiety, disinterest, etc.) (belonging to criterion D of the DSM-5) [6].

By scanning the components related to the COVID-19 pandemic at play during the lockdown, we showed how most PTSD symptoms could appear in this context, fore- shadowing a wave of post-traumatic symptoms subsequent to the current period[20].

While such a wave can occur, we have also seen how it arises right now from a context of exposure to a present chronic stress, and linked to an invisible threat against which protection is lacking. These elements constitute a more complex scenario than a “classic” traumatic event and rely on the concept of continuous traumatic stress described elsewhere[21].

Prevention measures for post-traumatic stress due to confinement

Measures to prevent PTSD occurring as a result of lock- down related to the COVID-19 pandemic echoes the factors that promote its occurrence. First, the shortest possible lock- down time seems to prevent the onset of PTSD[18]. Thus, the risk of resources loss is minimized, as much as the risk of exposure to violence. A number of measures depend largely on governments and not only on the health care system.

Concerning daily life, some measures can still be taken by individuals:

– Concerning life rhythms, it is essential to favor a daily life hygiene, in particular by keeping regular waking and bedtime. Expert recommendations are published on this subject[22].

– If protective measures are necessary and reminders of the existence of a necessary viral threat are required, any- one can decide to limit exposure to distressing information.

Individuals should decide to limit their daily consultation of news (i.e., 20 to 30 minutes per day, at a specific time of the day).

– Maintaining social relations even at a distance is funda- mental.

– Finally, in order to compensate for the prescribed social distancing, psychological hotlines were set up across the world to help those who are most isolated or the most vulnerable. Thus, the individuals presenting with stress symptoms that could be forewarning signs of future PTSD could find psychological support provided by professionals from their homes.

Finally, communication remains a major issue. The mis- sion of providing trustworthy information accessible to the public relies on mental health professionals, who did so by bringing together online recommendations[23, 24].

Lockdown and social isolation as vectors of psychotic symptoms?

As mentioned in the introduction, although there is a vast literature linking social isolation or deprivation to psychotic symptoms, none of the many studies on the psychological effects of outbreak-related confinement has addressed the issue of the emergence of psychotic symptoms. In this sec- tion, we focus on the presence or experience of psychotic symptoms such as hallucinations which, as a reminder, do not signify a psychotic state, when they are not associated with disorganized thinking or behavior. It should also be noted that psychotic symptoms such as hallucinations or experiences of persecution may occur in some cases of PTSD and that the occurrence of these symptoms is gener- ally increased in situations of stress. However, this section will only focus on the relationship between isolation and psychotic symptoms outside the traumatic context.

Social isolation and psychotic symptoms:

a brief review of the literature

The literature on social isolation experiences (alone or with other persons) in various contexts – polar, underwa- ter or island expeditions – shows an increase in psychotic symptoms: paranoia and hallucinatory experiences; flashes of light, impression of movement[25, 26]. It is important to specify that these symptoms 1) were observed in individuals previously selected on their emotional and psychological stability and trained to cope with these extreme conditions, 2) were correlated with the duration of the isolation and 3) disappeared at the end of the isolation.

Psychiatric symptoms, known as Intensive Care Unit (ICU) syndrome[27], have also been observed in isolated patients (in intensive care units). This syndrome includes visual hallucinations and sometimes paranoid delusions, not related to a neurological cause.

A series of earlier studies on the effects of solitary confi- nement in prisons showed that very strict confinement conditions (prisoner alone in a cell, and minimal envi- ronmental stimuli and social interactions) generated very deleterious effects on the mental health of prisoners[28].

The clinical picture presented by these prisoners, also called Security Housing Unit (SHU) syndrome [29], included an

agitated confused state associated with delusions (paranoia) and hallucinatory phenomena (in more than 40% of indi- viduals), but also agitation, impulsivity and often episodes of self-directed violence. In particular, Grassian observed that these prisoners were hypersensitive to external stimuli, and reported alterations in perception and derealization expe- riences[29]. Importantly, these symptoms were very often observed in individuals without a psychiatric history.

Several factors have been described to influence the impact of solitary confinement on the mental health of these prisoners: the degree of sensory deprivation, the duration of isolation, the person’s understanding of the reasons for his or her isolation, and the personality and psycho-cognitive- social functioning of the incarcerated individuals[30].

More recently, a longitudinal study confirmed that soli- tary confinement caused more psychiatric morbidity than non-solitary imprisonment (29% vs. 15%), mainly anxiety and depression disorders. Several participants developed episodes of visual hallucinations after 3 weeks (6 out of 37), but psychotic disorders related to the more modern condi- tions of isolation in the prison environment remained sparse [31].

Finally, many studies showed that there were close relationships between social isolation or loneliness and hallucinations in borderline personality disorder [32], Alzheimer’s disease[33], the psychotic continuum[34]or the general population[35].

What neuropsychological mechanisms can explain the relationships between social isolation

and hallucinations?

Social isolation often precedes and represents a risk fac- tor for the emergence of psychotic disorders[36]. To explain the neurological mechanisms underlying the occurrence of hallucinations, Hoffman proposed the hypothesis of social deafferentation[37]. Based on animal studies[38], Hoffman claims that severe social isolation during certain periods of development could induce cerebral reorganizations, partic- ularly in the associative cortex[37]. This analogy between social and sensory deprivation allows a better understand- ing of the mechanisms that can lead to hallucinations in isolation.

The relationships between sensory deafferentation and hallucinations have been clearly established for several years, and are well described in the case of complete sensory loss of sight or hearing[39]. One of the first obser- vations of this phenomenon relates to the Charles Bonnet syndrome, which corresponds to the appearance of visual hallucinations in people who have lost their sight [40].

About a quarter of people with hearing or visual deficits report hallucinations in the same sensory modality, in the absence of altered thinking or delusions[41]. It is also inter- esting to observe that the prevalence of these hallucinations increases with the severity of the sensory deficit[41]. In the same way as in the phantom limb phenomenon, the brain compensates abnormally for the loss of sensory stimula-

tion. It has been proposed that the absence or reduction of sensory afferents would lead the brain to react in an inappropriate way by markedly lowering the neuronal acti- vation threshold, in order to restore a certain balance[41].

These compensatory mechanisms would lead the brain to an unstable hyperexcitability [42], in turn responsible for hallucinations[43].

Overall, decoding sensory information requires the inte- gration and interpretation of signals reaching the brain but also the resolution of ambiguities inherent to the informa- tion around us. The decoding of this information and the detection of environmental changes are made possible by the prior knowledge that we have acquired through our experience and which modulates our perception, i.e. the priors. It is the balance between the incoming information and the priors that allow us to give information its meaning and resolve its ambiguities.

If cerebral hyperexcitability is yet to be demonstrated in the case of sensory deficit, the reduction of incoming sensory information is likely to upset the balance between sensory processing and priors, leading to a false perception of the environment that could underlie hallucinations[44].

Finally, reduced social contact may also affect more inte- grated processes of mentalization. More precisely, social isolation would prevent the “normalizing” function of social contact, which allows oneself to be confronted to others’

reality[45]. This lack of “normalization” would cause the emergence of psychotic symptoms. In the context of his research on the psychological effects of prison isolation, Haney points out that individuals generally rely on social contact with others in order to test and confirm their per- ceptions of the environment and the world around them [46]. The strict conditions of prison isolation would then prevent prisoners from being engaged in these processes of “social testing” of reality. A complete absence of social contact would make it very difficult to distinguish between what is real and what is not (‘reality monitoring’), or between what is internal and what is external (‘source monitoring’).

Thus, these situations of isolation can lead to the emergence of psychotic symptoms such as hallucinations, alterations in perception, or experiences of derealization.

Current lockdown linked to Covid-19 and risk of emergence of psychotic symptoms

Although the conditions of lockdown in our modern, prosperous and connected societies greatly differ from the situations previously described in literature, it is still important to question the potential emergence of psychotic symptoms in such circumstances. In the absence of data on this issue, one must remain cautious, but the literature above described fosters further exploration of the psychological impact of lockdown in terms of psychotic symptoms.

Although a majority of western populations experi- ences a lockdown that could be described as modern and connected, probably alleviating social deprivation, it is not the case for the whole French (or world) population.

The inequality of the lockdown conditions incites to take into account many factors that might worsen the negative effects of lockdown: home surface during lockdown, num- ber of people confined together, outside access, internet and telecommunications. As a result, certain populations could be identified as being at greater risk of develop- ing psychotic symptoms in situation of global lockdown.

Without being exhaustive, we can mention students living in small housing without outsides, inmate populations for whom social deprivation has become more pronounced, and elderly people already suffering from many hearing and/or visual disorders and very often kept away from the new technologies and internet.

Moreover, one should note that hallucinations are not specific of schizophrenia, they are on the con- trary observed in many other pathologies (Parkinson’s, Alzheimer’s, epilepsy), and even in non-clinical population, mostly in situations of increased stress[47]. Hence, patients with psychotic disorders are not the only vulnerable indi- viduals in case of global lockdown. It is therefore important to evaluate the possible emergence of symptoms, such as decompensation, in subjects vulnerable to psychosis, but also the emergence of hallucinations in the general popu- lation. Communicating about this risk, emphasizing that it does exist very widely, and that it is not necessarily asso- ciated with a disabling pathology, will contribute to the destigmatization of this symptom. This will also encourage those who suffer from it to talk about it and consult a medi- cal doctor or a psychologist. Badcock and colleagues have suggested that hallucinations in the elderly are underesti- mated because of their unwillingness to talk about them [48]. The lack of exploration of these symptoms in the stud- ies published so far can only contribute to perpetuating this taboo.

Lockdown as a psychotherapeutic tool? Parenthesis on the positive psychological effects of sensory and social deprivation

In order to counterbalance the potentially dramatic con- sequences of social isolation highlighted in the previous paragraphs, it is necessary to also mention some psychother- apies using lockdown and social isolation as therapeutic tools.

It is the case of the Morita therapy, a form of psychother- apy inspired by Zen Buddhism and created by Shoma Morita (1874-1938), a professor of psychiatry in Tokyo at the beginning of the 20^th century. Initially recommended to treat neuroses, and in particular “taijin kyofusho” [49]

(or anthropophobia), its spectrum of indications has gradu- ally broadened and this method is still quite popular today in China and Japan. In its original form, it comprises four phases, the first two of which include complete sensory lockdown and isolation. The first phase consists of a strict bed rest for one week during which any activity, whether reading, writing or any form of stimulation from the out- side world is prohibited (the patient can only eat, wash and

go to the toilet). The objective of this phase is to reduce conflicting thoughts and to encourage face-to-face contact with oneself. In the second phase, bed rest is reduced to 7-8 hours per day and minimal activities are allowed three days a week as well as regular contact with the elements of nature (fresh air, sun). However, any direct communication with the outside world is prohibited, except through a diary used as a means of communication with the therapist. The two following phases allow normal activities and prepare the patient’s life outside the hospital. The whole therapy usually lasts forty days (a quarantine) but the duration can be reduced. In fact, alternatives, called neo-Morita therapy, have since been developed, in which the treatment can be done at home or even in a group.

The general objective of the Morita therapy, especially through the period of sensory isolation and lockdown, is to promote a progressive acceptance of “reality as it is” (or

“arugamama”) or more specifically, a patient acceptance of symptoms considered as unpleasant. By this way, patients learn to look at them as part of a reality they can learn to live with. Some authors pointed out interesting parallels with the Acceptance and Commitment Therapy (ACT), both inspired by similar philosophical sources.

This approach led to many studies, mainly in Eastern countries but recently also in occident. A meta-analysis of 11 studies [50] showed significant effects of this therapy

combined with antidepressant treatment on depressive symptoms and on depressive remission compared to antidepressant treatment alone (with respective effect sizes of 0.61 and 1.37). The results are less conclusive for anxiety disorders[51]. Finally, a meta-analysis of 10 studies using this therapy in schizophrenia[52]reported a greater improvement of the general functioning, insight and neg- ative symptoms in patients. In general, the methodological quality of these studies was rather low and the studies were carried out in a cultural context markedly different from that of Western cultures. Nevertheless, the therapeutic principle of sensory deprivation finds a current echo in the increasing emergence of well-being stays offering individuals who are “hyper-connected” and “over-stimulated” by their daily life, moments of voluntary sensory deprivation, in which e-diets and suspended electronic or telephone contact with the outside world are an integral part of the “care”

offered.

Importantly, people benefiting from these therapeutic approaches based on sensory deprivation have chosen it;

the parallel with the situation of imposed lockdown reaches its limits here.

Conflict of interest None.

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