War Trauma, Mental Health, Aggression, and Violent-Extremism Among Former ISIS Terrorists

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Journal of Aective Disorders Reports 10 (2022) 100399
Available online 17 August 2022
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Research Paper
War trauma, mental health, aggression, and violent-extremism among
former ISIS terrorists
Rezhna Mohammed
a
,
b
,
c
,
*
, Frank Neuner
a
,
b
a
Department of Psychology, Clinical Psychology and Psychotherapy, Bielefeld University, Germany
b
Vivo International, Konstanz, Germany
c
Institute for Interdisciplinary Research on Conict and Violence, Bielefeld University, Universit¨
ate Straße 25, Bielefeld, NRW 33615, Germany
1. Introduction
Terrorism, the use of violence for allegedly political and religious
purposes, continues to be a global threat. Researchers from various
disciplines, especially the political and social sciences, have been
studying the causes of terrorism for decades. One key question has al-
ways been; what motivates terrorists to commit severe violence, often
against civilians? Early psychological theories have followed the com-
mon public perception that perpetrators of atrocities must be, to some
extent, insane or at least carry antisocial personality traits (Borum,
2004). Early psychoanalytic theories of terrorism were mainly based on
anecdotal post-hoc explanations, with a major focus on the individual
and not group violence, and with little support from empirical studies
(Cohen, 2019). However, the observation of terrorist groups’ behavior
provides little evidence for severe mental disorders such as schizo-
phrenia and other psychotic disorders (Trimbur et al., 2021; Victoroff,
2005). As a consequence, one can see mental health in the academic
study of terrorism as a pendulum that has gone from considering mental
illness the dening feature of terrorists, only those who are mentally ill
can be terrorists, to being the exclusionary factor for being a terrorist,
hence the understanding; terrorist organizations have a system in place
to exclude the mentally ill in the recruitment process (Corner and Gill,
2015).
Despite little empirical support, mental health maintains a central
role in the public perception of terrorist motivations. Common displays
assume a dichotomy of motivations of terrorist attacks: the mentally
impaired perpetrator with little political or religious motivation versus
the truly determined terrorist who is capable of planned attacks. How-
ever, recent accounts have emphasized that such a dichotomy may be
oversimplied. Mental health impairment may indeed play a role in
terrorism and violent extremism and often be overlooked in lack of the
opportunity of a thorough clinical assessment of perpetrators (Lankford,
2016; Misiak et al., 2019; Sanir et al., 2017; Trimbur et al., 2021).
Psychological disorders, such as depression and suicidality, may
contribute to terrorism but be often overlooked (Misiak et al., 2019)
since they may not be visible in blunt behavior.
There is evidence that factors behind joining terrorist groups may
vary from country to country, suggesting that a more differentiated
approach is needed (Fair and Shepherd, 2006). In particular, it is likely
that different mechanisms contribute to terrorism in countries that are
affected by war. Terrorism appears to be a unique phenomenon in the
context of war and conict, since terror organizations are not restricted
to operating from hiding but may transform into rebel armies that wage
open warfare, conquering whole regions and building up state-like
structures, (Murthy and Lakshminarayana, 2006). Iraq has been
embroiled in conict and war for many decades (Ashton and Gibson,
2013; Lowry, 2003) and has become a haven for different terrorist
groups (Mohamedou, 2018). The self-declared Islamic State of Iraq and
Syria (ISIS) had taken over third of the country in 2014, leading to years
of devastation, genocide, and depletion of the infrastructure and human
resources of the country (Mansour, 2017; Ziedel and Al-Hashimi, 2019).
In the context of enduring conict, the consideration of mental
health seems imminent, since it is evident that war and conict have a
negative impact on the mental health of the population (Alghzawi,
2015; Betancourt et al., 2020; Catani et al., 2008; Karunakara et al.,
2004; Miller and Rasmussen, 2017, 2010). Exposure to war and political
violence is linked to high rates of posttraumatic stress disorder PTSD
(Burri and Maercker, 2014) and depression (Jabbar and Zaza, 2014;
Kar, 2019; Stein et al., 2021) among civilians. Combatants, including
members of irregular forces, are also affected by high rates of psycho-
logical disorders. For example, studies among former child soldiers in
Africa show high rates of PTSD and depression (Hecker et al., 2013;
Hermenau et al., 2013; K¨
obach et al., 2015). At the same time, high
levels of continuing aggression, including intimate partner violence
have also been documented among war veterans(MacManus et al., 2015;
Tharp et al., 2016). Since exposure to war violence affects regular as well
* Corresponding author at: Institute for Interdisciplinary Research on Conict and Violence, Bielefeld University, Universit¨
ate Straße 25, Bielefeld, NRW 33615,
Germany.
E-mail address: rezhna.mohammed@uni-bielefeld.de (R. Mohammed).
Contents lists available at ScienceDirect
Journal of Affective Disorders Reports
journal homepage: www.sciencedirect.com/journal/journal-of-affective-disorders-reports
https://doi.org/10.1016/j.jadr.2022.100399
Received 11 April 2022; Received in revised form 18 July 2022; Accepted 14 August 2022

Journal of Aective Disorders Reports 10 (2022) 100399
2
as irregular forces, it seems likely that members of terrorist groups who
were participating in combat also present with high levels of aggression
(Marazziti and Stahl, 2019).
Next to the relationship between combat experiences and aggression,
it may be speculated that the war context also affects radicalization
processes, since exposure to war during childhood has an impact on the
formation of identity. Youth who live in a context of organized violence
and political violence form a collective identity, and tend to have higher
identication with their group (Elbedour et al., 1997; Feshbach, 1994)
that may include pro-war attitudes (Feshbach, 1994), in turn, identity
problems is a predictor of redicalization (Jahnke et al., 2021). Perceived
injustice has been found to increase identication with radical groups
(Moskalenko and McCauley, 2009) and drive for revenge have been
documented as one of several factors that lead people to join radical and
terrorist groups (Wiktorowicz and Kaltenthaler, 2016).
In addition to the history of war in Iraq, terrorism is a process that
starts with simple steps towards radicalization and evolves into acts of
violence (Horgan, 2009). It is possible that the faith campaign
(Al-Hamla Al-Imaniyah), invented and enforced by the Saddam Hussein
regime in the period between 1990 to his last days of rule in Spring
2003, was a step towards shifting the country as a whole in the direction
of Islamist extremism (Helfont, 2014, 2018).
In the present investigation, we studied a sample of men who were
incarcerated for acts of terrorism related to ISIS in a prison in Kurdistan,
Iraq. The aim of this study was to determine the relationship between a
history of trauma and perpetration, mental health, radical attitudes, and
current aggressiveness. In contrast to studies that try to explain the onset
of terrorism by observing individuals from the general population with
increasingly radical ideas, this sample provides the opportunity to un-
derstand the relationship between various indicators among those who
have in fact become terrorists documented by radical actions, or at least
those who were considered to be terrorists by their environment. In this
way this study may contribute to the explanation of the maintenance
rather than the onset of terrorism on an individual level. This question is
particularly relevant since incarceration has shown to bring little change
to terrorist motivations, but were even considered as a breeding ground
for recruitment by terrorist groups, especially by religiously motivated
terrorist groups (Jones, 2014; Silke, 2014).
As the main outcome parameter, we assessed readiness for aggres-
sion using a standard aggression instrument (Buss and Perry, 1992).
Although this instrument was not developed to assess willingness to
resume politically or religiously motivated terrorism, we consider the
components of retaining hostility, anger, and physical aggression, in-
dependent from the specic motivation, as risk factors for a maladaptive
development after release from prison, either directly by motivating acts
of terrorism or indirectly by interfering with a successful adaptation to a
peaceful society. We have reason to assume that aggression is associated
with trauma-related psychopathology in this sample, since ISIS ghters
in Iraq had commonly been in combat against regular government forces
and were confronted with high levels of violence in the context of the
civil war. Since war trauma seems to be associated with aggressiveness
in ex-combatants independent of the specic context (MacManus et al.,
2013; Morland et al., 2012), we expect that PTSD contributes to hos-
tility, anger, and physical aggression also in this sample, over and above
of the effects of radical ideas and former perpetration. Specically, we
expected that war exposure was correlated with aggressiveness, and that
this relationship was mediated by PTSD. To test this assumption, we
adapted and developed specic instruments for the culturally adequate
assessment of events and symptoms that were applied in interviews
conducted by a psychologist.
2. Method
2.1. Participants
The sample was recruited from residents of a prison in Erbil,
Kurdistan Region of Iraq (KRI). Purposive and snowball sampling stra-
tegies were used to select the study participants. We selected partici-
pants who were convicted of terrorism crimes under Iraqi law and
offered to interview them. All participants were male (N =55). The
mean age was 29.10 years (SD =5.57, range: 22-54). Almost all par-
ticipants were Arabs and of Sunni Muslim religion (98.2%). They were
from different villages, towns, and cities in central and northern Iraq.
History of displacement was high among the sample, with 63.6% having
been displaced from their city of origin at least once. Overall, 63.5%
were married, 34.5% were single, and 1.8% were separated from their
spouse. Average years of formal schooling was M =8.07 years (SD =
4.34). Eighty percent of the sample met criteria for depression. Despite
the fact that prisoners were convicted of ISIS-related crimes, 38.2% of
the sample reported having joined ISIS or another terrorist group.
2.2. Procedure
This cross-sectional study was carried out with the permission of the
General Directory of Social Reformatory in the Kurdistan Region of Iraq
(KRI). This directory manages all prisons in the region. After extended
meetings with the staff at the prison, a seminar with the inmates was
conducted by the primary author to explain the goals and procedures of
the study and provide the opportunity to prisoners to choose whether to
participate in the study. The purpose of the study was made fully
transparent to the inmates. After that, face-to-face interviews began with
the study sample. A list of the inmates was initially provided to the main
researcher by the department of social workers at the prison. Structured
clinical interviews were conducted in the Iraqi dialect of the Arabic
language, all interviews were carried out by the rst author of this
paper. After the rst week of interviews, snowballing sampling took
place, where the interviewer asked some of the interviewees to provide
her with names of people who would possibly like to participate in the
interviews (5 participants were recruited this way). Some participants (3
in total) volunteered to participate of their own accord. Each interview
had four parts, starting with a detailed informed consent that was read to
the participants at the beginning of the one-on-one interview, followed
by a demographic interview, participants’ age, years of schooling, and
some information about the number of siblings and place of origin were
asked here, afterward, participants were asked about their history of
violence both as victims and perpetrators, the nal part of the interview
was the clinical part participants were asked about PTSD and depression
symptoms, aggression and suicidality were asked here too. All but one of
the participants who were approached agreed to the interview. All in-
terviews were conducted in an ofce that was dedicated to the inter-
viewer for the period of the interviews inside the adults’ reformatory
prison in the KRI.
2.3. Protection, safety, and security
To protect the condentiality of the participants in the prison setting,
all interviews took place in a private room away from the management
ofces and on the same oor as the prison cells. Only the researcher and
the participant were in the room during the interviews. As part of the
study information, participants were informed about the health unit
inside the prison that comprised of social workers, two trained psy-
chotherapists, and a psychiatrist who visited once a week and on an as-
needed basis. A referral system with the health unit was initiated by the
primary researcher before the interviews took place. If requested by the
participant, referral was made by the researcher directly to the psy-
chotherapist. Participants were made aware that some initial informa-
tion would be shared with the psychotherapist as part of the referral
meeting, such as suicidality and the severity of mental health symptoms
as shown in the assessment completed by the participant as part of this
study.
R. Mohammed and F. Neuner

Journal of Aective Disorders Reports 10 (2022) 100399
3
2.4. Instruments
Some study instruments were developed for the purpose of this
study, and others were adapted following an extensive preparation
phase. To ensure an informed face-validity of the instruments, in-depth
interviews were carried out with key informants within the United Na-
tions and other humanitarian organizations working with the study
sample as well as with government ofcials in the directory of re-
formatories and within the prisons. In addition, a focus group discussion
was conducted with selected participants from the study population in
the prisons, some of which ended up participating in the one-on-one
interviews later. Within this focus group discussion, we explored the
prisoners’ perspective on ideologies, aggression, traumatic experiences,
and mental health, as well as issues regarding condentiality and
openness to disclose. As one result, lists of possible war-related events,
ISIS-related events and perpetration events were constructed. The entire
package of study interview scales was then used in further focus group
discussions to test for the feasibility for the study sample. Some of the
scales (demographics, perpetration events, identication with the
terrorist group, and war related events) were developed in Arabic lan-
guages. Validated translations were available for other scales (PCL-5, D-
HSCL and WAEC). Some scales (family violence) were translated into
Arabic using established translation procedures that involved a blind
back-translation and a discussion of the discrepancies between original
and back-translation involving both experts as well as participants.
2.5. Demographics
All instruments were administered in an in-person interview format.
Initial questions regarding participant demographics were asked, such
as age, marital status, number of children, ethnicity, religion, and edu-
cation. Questions regarding imprisonment, displacement, and whether
or not they had joined armed groups were also asked.
2.6. Family violence
Exposure to violence was assessed by focusing on different time pe-
riods of the ex-combatant’s life, starting with childhood. A modied
version of the Family Violence Scale (Catani et al., 2008) was adminis-
tered. Participants were asked about experiences of physical violence (e.
g., “have you been hit?”), verbal violence (e.g., “have you been told you
are no good?”), sexual violence (e.g., “have you been raped”), and
neglect (e.g., “have you been neglected") that were committed by their
caregiver. The same questions were asked to examine whether the
participant witnessed a family member experiencing those types of
violence. All questions were dichotomous and could be answered with
either yes or no. The sum score for experienced and witnessed family
violence resulted from the sum of afrmative responses to different
types of violence.
2.7. Perpetration events
Perpetration events were assessed by presenting ten types of violence
that were associated with ISIS and other armed groups in the region. The
scale was developed for the purpose of this study. The questions were
generated from focus group discussions with the study sample and ex-
periences of the study authors from the eld. Examples of those ques-
tions are “have you attacked another armed group” and “did you torture
anyone.” The full scale is available as supplemental material. The sum
score for perpetrated violence resulted from summing the "Yes" answers
to the different events listed in the scale, answers ranged from 0 to 10.
2.8. Identication with ISIS
Giving the uniqueness of the Iraqi context, we decided to develop our
own scale of identication with beliefs promulgated by ISIS rather than
applying an available scale on radical ideas. This scale was constructed
as a result of the focus group discussions with prisoners and key in-
formants within UN Agencies and Humanitarian Organizations. We
developed 18 items, each of them representing a central belief associ-
ated with Islamist extremists. The participants answered each question
in a dichotomous "Yes" or "No" format. For example, the following
statements were included: “participation in the ght with the armed
groups is a moral obligation” and “some of the goals of the group is right
for my ethnic/religious group.”
As a further aim of this study was not only to assess the beliefs held
by participants but also to identify the presence of any temporal changes
of the beliefs, each question was asked four times to assess the belief
while among the terrorist group, the current belief, the belief of close
family members as well as the belief of friends. Participants were asked
to retrospectively rate their identication with these beliefs at each time
point. For the purpose of this study, only the items assessing current
beliefs of the respondents were used. The sum score of the current beliefs
were then calculated manually by adding all the positive answers to
create a new composite variable.
2.9. Aggression
To assess aggression, the Buss and Perry Aggression Scale (BPAS) was
administered (Buss and Perry, 1992). This scale is widely used to assess
aggression. It consists of 29 items, and divides aggression into four
subgroups, physical aggression (9 items; “If I have to resort to violence to
protect my rights, I will”), verbal aggression (5 items; “I tell my friends
openly when I disagree with them”), anger (8 items; “Some of my friends
think I am a hothead”), and hostility (8 items “When people are espe-
cially nice to me, I wonder what they want”). The rst two subgroups
represent the instrumental component of aggression. Instrumental
aggression is aggression that is intentional and planned, it is more
cognitive than affective and maybe completely cold and calculating.
Anger is the psychological activation and preparation for aggression and
it represents the emotional component of aggression. Emotional
aggression is referred to aggression that occurs with only a small amount
of forethought or intent and that is determined primarily by impulsive
emotions (Jhangiani, 2014). Whereas hostility is the feelings of oppo-
sitionality and injustice, representing the cognitive component of
aggression. Anger acts as psychological bridge connecting the instru-
mental and cognitive component. The participants responses were
categorized on a ve-point Likert scale ranging from (0) “very unchar-
acteristic of me” to (4) “very characteristic of me.”
2.10. War trauma exposure
Levels of exposure to war events were determined by administering a
modied version of the War and Adversity Exposure Checklist (WAEC;
(Ibrahim et al., 2018). The WAEC is a 29-item scale created based on
previous studies with Iraqi internally displaced persons in the camps of
the Kurdistan Region of Iraq. This scale assesses common traumatic
experiences and adversities in war regions. It includes items such as
“have you ever been deprived from food or water due to war or ight,”
“have you ever witnessed an execution,” and “have you ever lost anyone
close to you due to the war.” Participants rated their responses as either
“yes” or “no.” The sum score was calculated by summing respondents’
“Yes” answers.
2.11. PTSD
Participants were asked to determine which of the events they
mentioned from the life events scale (LEC) on the PCL-5 is the worst
event they have ever experienced, some specic questions from the life
events checklist of the PTSD Checklist (PCL-5) were used to understand
the worst event in more details. To measure PTSD, the PTSD Checklist
for DSM V (PCL-5) was used. PCL-5 is a 20 questions scale that measures
R. Mohammed and F. Neuner

Journal of Aective Disorders Reports 10 (2022) 100399
4
the four clusters of PTSD based on the DSM V and looks at symptoms
severity on a ve-point Likert Scale ranging from “0 not at all” to “4
extremely.” All participants are asked to think about the previous month
when answering the questions on this scale (Blevins et al., 2015). We
opted for using the validated Arabic translation of the instrument that
been used previously in Iraq (Ibrahim et al., 2018).
2.12. Depression
To examine depression, the Arabic translation of the Hopkins
Symptoms Checklist for Depression (Hesbacher et al., 1980) was used.
This checklist is a 15-item scale that is based on the DSM-5. Answers
were distributed on a four points Likert Scale ranging from “1 not at all”
to “4 extremely”(Ibrahim et al., 2018).
2.13. Statistical analysis
In order to examine the relationship among the variables exposure to
war events, PTSD, depression, family violence, perpetration events,
identication and aggression, a correlation analysis was conducted.
Another correlation analysis was conducted to further understand how
the variables interacted when aggression was broken down to its sub-
groups. A multiple regression analysis was carried out to disentangle the
contribution of single variables in the association with aggression while
the effect of the other variables was controlled.
Bootstrapping was used to test the mediating role of PTSD between
war events and aggression. Bootstrapped 95% CIs around the indirect
effect of war events on aggression through PTSD were generated using
1000 re-sampled datasets. This procedure entails re-sampling with
replacement to generate a distribution of a given mediation effect.
Bootstrapping is more powerful than conventional tests, such as Sobel’s
z, because it considers the positive skew inherent to mediation effects
(Preacher and Hayes, 2008). Bootstrapping was conducted using Hayes’
(2019) PROCESS macro version 3.3 for SPSS (Hayes, 2019), which
generates bias-corrected condence intervals to further offset the
aforementioned positive skew. All analyses were conducted using SPSS
v. 25.
3. Results
3.1. War exposure
Our participants reported experiencing between four and 22 war-
related events (M =11.69, SD =4.49), with 3.6% of the sample hav-
ing reported experiencing at least four war-related events, and 1.8%
experiencing 22 war-related events. The mode number of events expe-
rienced was 14 (14.5%). Fig. 1 presents the percentages of the most
frequently reported events.
3.2. Family violence
Participants experienced between 0 (16.4%) and 10 (1.8%) family
violence events, with six (18.2%) events being the most frequently-
reported number of events (M =4.30 SD =2.83). Nearly three-
quarters (74.5%) of the sample reported having been hit by a care-
giver as a child, 72.7% reported having witnessed another family
member being hit by a caregiver as a child, 54.5% reported being hit
with an object by a caregiver as a child, and 52.7% reported having
witnessed other family members being hit with an object by a caregiver.
Just over 16% of our sample reported being wounded with a weapon by
a caregiver as a child, and 14.5% reported witnessing other family
members being wounded with a weapon by a caregiver. Nearly half
(47.3%) of the sample reported having been told they are not a good son
by a caregiver while growing up, 38.2% reported witnessing other
family members being told so. Just over a quarter of participants
(27.3%) reported experiencing neglect and 25.5% reported witnessing
neglect happening to other family members. A small number of partic-
ipants (3.6%) reported having being touched in their private parts as
children by a family member and the same percentage reported having
witnessed other family members experiencing the same. None of the
participants reported being raped as a child or witnessing other family
members being raped by a family member. Fig. 2 presents percentages of
the most frequesntly reported family violence events.
3.3. Perpetration events
Violence perpetrated by our sample varied between 0 and 6 events
(M =1.29 SD =1.54). In the sample, 14.5% reported having attacked
Fig. 1. Percentage of war events experienced by the sample.
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Journal of Aective Disorders Reports 10 (2022) 100399
5
other armed groups, 1.8% reported having forced others to have sex
with them, 1.8% reported having tortured others, and 7.3% reported
having punished others.
3.4. Mental health prevalence
Overall, 54.5% of the sample meet criteria for a PTSD diagnosis using
33 as the standard international cut-off score suggested for the instru-
ment (Blevins et al., 2015; PTSD Checklist for DSM-5 (PCL-5), 2016).
However, this number climbs to 76.4% when using 23, the cut-off score
suggested for the Iraqi population (Ibrahim et al., 2018).
3.5. Predictors of aggression
Table 1 provides the bivariate and the multivariate relationship be-
tween war events, mental health variables, and aggression (sum score of
the aggression instrument).
3.6. PTSD and depression as mediators between aggression and war
events
The sum score of traumatic events was positively correlated with
aggression (β =3.3, t =5.73 p <.001), depression (β =.69, t == 2.41, p
<.01), and PTSD (β=1.64, t == 4.10, p<.01). To examine the mediating
role of PTSD and depression in the association between war events and
aggression we tested a simple mediation model. Controlling for the
mediating inuence of PTSD, the direct effect of traumatic events on
aggression reduced but remained signicant (β =2.33, t == 3.85, p <
.0003) and when controlling for the mediating inuence of depression,
the direct effect of traumatic events on aggression reduced but remained
signicant (β =2.53, t == 4.95, p <.0000). The indirect effect was
tested with a bootstrap estimation procedure. The indirect effect of war
events predicting aggression through PTSD reached signicance (β =
.93) and depression (β =.73), Fig. 3.
3.7. Presents the correlation between the different variables
Table 2
4. Discussion
In the present study, which, to the best of our knowledge, is the rst
of its kind to investigate the associations of mental disorders, war events,
and aggression among a sample of detained terrorists in a prison in Iraq,
we found high levels of trauma exposure and related psychological
disorders in this sample. Traumatic experiences and posttraumatic stress
disorder were strongly related to aggression. These associations are in
line with what the eld has learned about the relationship between
traumatic exposure, PTSD and aggression (Jakupack et al., 2007)
Notably, this study found that self-reported ongoing aggression
among this group of terrorists was not associated with self-reported
identication with radical ideas, but rather with various variables that
indicate a trauma exposure and trauma-related disorders to have a
bigger role. Aggression was correlated with a number of biographical
variables, including a history of family violence, war events, and
perpetration of violence in ISIS. In a multivariate analysis, exposure to
war trauma outperformed the contribution of other types of violence
and perpetration of violence when looking at aggression. While this
nding might initially appear surprising since aggression and violence
by terrorists has usually been explained by political and religious mo-
tives, the relationship between war trauma and aggression is consistent
with a broad range of studies of former combatants in different settings
(Hecker et al., 2012; MacManus et al., 2013; Morland et al., 2012;
Skotnicka, 2012; Taft et al., 2009; Weierstall ad Elbert, 2011), including
irregular forces/paramilitary groups (Hermenau et al., 2013). Indeed,
this nding is consistent with the distinction between radical ideas and
behaviour that has been emphasized in current accounts of terrorism
(McCauley and Moskalenko, 2017) since both aspects of terrorism might
be only loosely related.
The relationship between traumatic war events and ongoing
aggression could possibly be explained through a habituation to
violence and to learning and employment of violent means to resolve
conicts. However, the fact that the effect of war trauma remained even
after controlling for perpetration of violence in the war suggests that
other mechanisms should contribute to this relationship. In fact, it seems
that psychopathological processes carry the association between trauma
and aggression at least in part. We showed that posttraumatic stress
disorder mediates some of this relationship, although the direct effect of
war trauma remained signicant. In general, aggression seems to be
associated with anger and hostility among samples with military-related
war experiences, as documented by this meta-analysis (Orth and Wie-
land, 2006)
Taken together, in terms of mental health, war events, and aggres-
sion, this sample of ex-terrorists shows many commonalities to other ex-
combatants of regular and irregular forces. PTSD among veterans
Fig. 2. Percentage of sample reported experiences of family violence.
Table 1
Predictors of aggression.
Predictors Standardized ß-
Coefcient
p Zero-order
correlation
p
War Events .462 .000 .619 000
PTSD .057 .692 .577 000
Perpetration
Events
-.078 .485 .289 .016
Identication .087 .354 .052 .354
Family Violence .219 .033 .485 000
Depression .340 .015 .595 000
a. Dependent Variable: Aggression, present R
2
for the multiple regression
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Journal of Aective Disorders Reports 10 (2022) 100399
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(Morland et al., 2012; Tharp et al., 2016; Voorhees et al., 2017; Watkins
and Laws, 2018) and among civilians residing in a war context is well
documented (Chung and Freh, 2019; Farhood et al., 2006; Neria et al.,
2010; Tekin et al., 2016). Still, the prevalence rate of 54.5% of PTSD is
exceptionally high, even when compared with Iraqi refugees and nd-
ings among criminal gang members (Kerig et al., 2016; Return Working
Group et al., 2019; Wood and Alleyne, 2010; Wood et al., 2017). This
high rate of mental disorder among afliates of a terrorist group chal-
lenges the common understanding that terrorist groups rely on mentally
healthy members and purposely exclude the mentally ill during their
screening process, as they deem them unreliable (Horgan, 2009, 2014;
Silke, 2014). However, in lack of a detailed temporal assessment or a
longitudinal observation we cannot determine to what extent the par-
ticipants had been traumatized before recruitment, during combat, or
after imprisonment. It is noteworthy that almost all of the participants
reported being tortured and some mentioned that this had happened
during interrogation in captivity. At the same time stressors related to
the imprisonment might contribute to the maintenance of psychopa-
thology (Kupers, 1999). With the high number of traumatic events
experienced by the study sample, the building block effect of the cu-
mulative trauma can also help explain the high rates of mental disorder
among this sample (Neuner et al., 2004; Rieder and Elbert, 2013; Steel
et al., 2009) More than eight out of 10 participants (83.6%) reported
being subjected to at least one family violence event. Family violence
during war and conict is well-documented (Saile et al., 2014) and can,
in turn, contribute to aggression and delinquent behaviour later in life
(Delisi et al., 2011; Fagan and Wexler, 1987)
The present study reected and extended many ndings in the
literature on terrorists and motivation. For example, this study drew on a
very specic sample of prisoners who were convicted of crimes related
to terrorism. It can broaden our view on the understanding of terrorist
motives and mental health beyond the study of radicalization processes
themselves and providing insight into the ways in which aggression is
maintained in a sample of men convicted of engaging in acts of
terrorism. However, studying this sample comes with some
compromises and limitations that must be considered when interpreting
the results. First and foremost is the sample itself; even though every
possible effort was made by the lead researcher to ensure the sample met
the inclusion criteria, it is unclear if all participants would really qualify
as terrorists or whether some individuals were falsely accused, since for
the classication of participants as terrorists we needed to rely on the
validity of the legal sentences of the prisoners. Since we have no means
to validate this information, it is possible that an unknown number of
respondents were victims of false accusations and, consequently, falsely
designated as terrorists. In the interviews, only a minority of participants
admitted that they had joined with ISIS and the nature and number of
perpetration events admitted by the participants seems low given the
reasons for participants’ detainment. Since we depended on in-
terviewees being incarcerated for terrorism-related crimes, we were
entirely dependent on the rule of law in Iraq and functioned on the
assumption that all charged of terrorism, were actually terrorists.
Another limitation is that the sample was self-selected, which makes it
far from representative of former terrorists in this context or even the
prisoners within the facility itself. We were also limited due to some
limitations forced upon us not to ask about different types of aggression,
like appetitive aggression and terror motivated aggression. The ndings
were entirely reliant on retrospective report on events and symptoms. It
is also important to note that this is not a causal study but rather a cross-
sectional one, and as such the ndings cannot give insights into causes of
terrorism but rather explains what the sample reported in a given point
in time. The setting of the prison might bring about response biases,
interviewees could have answered questions to what they perceived to
be socially desirable and not what was factual for them, causing missing
out on some probable radical ideas or perpetration of violence that went
unreported. Keeping these limitations in mind, the present study func-
tions as a rst step in generating a deeper understanding not just of the
events that may predispose an individual to radicalization, but also the
drivers of aggression and violence once radicalization occurs.
Fig. 3. Mediating role of PTSD and depression in the correlation between the sum of war events and aggression. **p <0.005, ***p <0.001
Table 2
Correlation between mental health, Aggression, perpetration and family violence
Variables I II III IV V VI VII VIII IX X XI
War Events I - .491** .315* .538** -.023 .303* .619** .498** .563** .545** .473**
PTSD II - .721** .321* .041 .319* .577** .586** 273* .469** .490**
Depression III - .168 0.10 .368** .595** .502** .264 .527** .567**
Perpetration Events IV - .171 .127 .289* .275* .281* .168 .246
Identication V - -.077 .052 .071 -.100 -.055 .172
Family Violence VI - .485** .401** .420** .347** .440**
Aggression VII - .856** .745** .882** .797**
Physical Aggression VIII - .551** .739** .496**
Verbal Aggression IX - .629** .474**
Anger X - .543**
**
Correlation is signicant at the 0.01 level (2-tailed).
*
Correlation is signicant at the 0.05 level (2-tailed).
R. Mohammed and F. Neuner

Journal of Aective Disorders Reports 10 (2022) 100399
7
5. Conclusion
Contrary to the common knowledge in the eld of violent extremism
research, our sample of prisoners who were convicted for crimes related
to terrorism show high rates of mental illness, in particular trauma-
related disorders. Acknowledging the caution with which the present
ndings must be interpreted, this study points to the need to consider
mental health parameters in any attempts to rehabilitate and reintegrate
former terrorists who have previous experiences in combat. At the same
time, continuing aggression was related to trauma exposure and post-
traumatic stress disorder. This nding can contribute to the counter-
terrorism and deradicalization efforts and programs, emphasizing that
understanding violent extremism and terrorism is not a one-size-ts-all
situation. War- and conict-related adversities clearly play a huge role
in aggression and mental health problems among terrorists who were
participating in combat. In order for rehabilitation and reintegration
programs to be fruitful, a trauma-informed therapy, tailored to the
context, could be a vital approach in increasing functioning, decreasing
aggression and thus reducing the likelihood of re-engaging in terrorist
groups for ex-combatants.
Author note
The authors of the present study have no potential conicts of in-
terest to report.
This study was supported by the German Academic Exchange Service
as part of a PhD scholarship to the rst author. We are grateful to all of
our participants for their active involvement. We offer special thanks to
the directorate of Labor and Social Affairs in Kurdistan Region of Iraq for
their support of the study. A special thanks to all the scholars at the
Institute for Interdisciplinary Research on Conict and Violence (IKG),
particularly Prof. Dr. Andreas Zick and Dr. Arin Ayanyan for their sup-
port and help in the design of the paper. We would like to express our
gratitude to Dr. Verena Ertl for her support and insights in the design
process. Special Thanks to Justin Preston for his valuable inputs and
review. Heartfelt thanks to Hersh E. Kaka Shin for his continuous
support.
Authors contribution
Both authors developed the study concept and contributed equally to
the study design. Testing, data collection, data analysis, and interpre-
tation was carried out by R.M. under the close supervision on F.N. R.M.
drafted the paper under the supervision of F.N., and F.N. provided
critical revisions. Both authors approved the nal version of the paper
for submission.
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