Peace efforts in the country have ended 50 years of intense
conflict. Now, scientists are studying former fighters and victims
as they attempt to heal.
By Sara Reardon
When she first began studying the people who had terrorized her
country, Natalia Trujillo prepared herself to come face to face with
She would be interviewing former combatants from the long, bloody
conflict that had gripped Colombia for more than 50 years. The
complex power struggle between guerrilla insurgents, the government,
paramilitary groups and drug traffickers had killed hundreds of
thousands of people and displaced millions. Four of Trujillo’s
family members had been kidnapped, and the violence had driven her
father from his farmland. Some of her colleagues had experienced
Trujillo, now a neuroscientist at the University of Antioquia in
Medellín, was interested in studying the psychological roots of
violence by looking at fighters who had laid down their weapons and
were trying to re-enter civilian society. Her chance came in 2010,
with a government reintegration programme that had gathered hundreds
of ex-combatants for the day in Medellín’s botanical garden.
She and her research team entered the enclave with a battery of
cognitive tests, panic buttons — in case something went wrong — and
some preconceived ideas. “I thought people who can kill their
neighbours, that can destroy their communities, that can have the
heart to force other people to abandon their farms — they have to be
really bad,” Trujillo says. She found a few who met her
expectations. With chains around their necks and boastful swaggers,
some tried to intimidate the researchers. But more often, the
scientists found ordinary people, strolling in the garden and eating
ice cream with their children.
“At the beginning I was pretty disappointed,” she says. If something
were wrong with their brains, it would provide an easy explanation
for the evil they had done. But after studying more than 600
combatants, she has begun to grasp the complexity of their
experiences. “I realized not all of them are sociopaths. I realized
most of them are also victims.”
That recognition has led Trujillo and her colleagues to re-examine
not only their own feelings about ex-combatants, but also the
country’s approach to dealing with them. Colombia’s government is
currently engaged in one of the largest peace efforts in history. As
part of a 2016 treaty with the left-wing guerrilla group known as
the Revolutionary Armed Forces of Colombia (FARC), the government
will grant amnesty to fighters who leave the conflict and complete a
re-incorporation programme, provided they have not committed serious
crimes. Around 6,800 FARC fighters have entered already.
The effort, which is politically controversial and expected to cost
129.5 trillion Colombian pesos (US$46 billion), faces overwhelming
odds. But it grants scientists a unique opportunity to understand a
population that has both inflicted and suffered the horrors of war.
Most research into the psychological roots of violence and trauma
has been performed with veterans from wealthy countries who fought
in conflicts far from home. Most of Colombia’s ex-combatants, by
contrast, have little education and are trying to re-enter the same
society they once terrorized. There, they face enormous stigma and
resentment, which makes it difficult for them to find work and form
relationships with others.
“I realized not all of them are sociopaths. I realized most of them
are also victims.”
A handful of scientists are now studying the former fighters in
unprecedented detail, in the hope that they will be able to inform
and guide the peacemaking process. They have found that years of
isolation and exposure to violence might have altered the
ex-combatants’ psychology and cognitive processing in subtle ways.
In laboratory tests, many have difficulty empathizing with others
and make flawed ethical judgements — shortcomings that could affect
how they engage in civilian life.
Scientists are now setting up long-term studies in towns that were
plagued by conflict, to track how cognition and attitudes might
change over the course of the reconciliation process, both for
ex-combatants and for civilians. The data could eventually inform
other war-torn countries’ recovery efforts.
But the research is also revealing just how deep the challenge is.
And some experts worry that the care available to ex-combatants in
the meantime is inadequate. “It’s going to be incredibly difficult
to get out of this vicious cycle,” says Jiovani Arias, a
psychotherapist and political scientist at the University of the
Andes in Bogotá. Without investment in improving mental health, he
says, the legacy of violence that affects ex-combatants and
civilians alike could torpedo Colombia’s precarious peace efforts.
The road to peace
Colombia’s armed conflict took root in the 1960s and waxed and
waned as various militant groups vied for control of Colombian
territory. Terrorist attacks tallied by the Global Terrorism
Database reflect only some of the 260,000 estimated deaths
attributed to the conflict. About 7 million people were
displaced by the fighting and thousands were kidnapped.
Towards the end of the 1970s, civil unrest against the Colombian
government emboldened guerrilla groups such as the FARC and
High-profile attacks in the subsequent decade include the siege
of the Palace of Justice in Bogotá in 1985, and the bombing of
Avianca flight 203, by drug lord Pablo Escobar, in 1989.
The 1990s saw protracted fighting as paramilitary groups, often
funded by political elites and drug traffickers, grew in power.
The Colombian military receded from many parts of the country.
By the mid-2000s, several paramilitary groups had entered into a
peace deal with the government. Still, the fighting wore on with
FARC until a ceasefire in June 2016. The final pact was signed
in November of that year.
Under the agreement, thousands of former FARC combatants are
entering designated ‘transit zones’ throughout the country —
known officially as territorial spaces for training and
reincorporation (ETCRs). Here, they will prepare to re-enter
Colombian society. But several guerrilla groups continue to
fight, including 1,000 FARC ‘dissidents’ who have refused to
sign on to the accord.
As a bus full of scientists pulls into the town of Vista Hermosa in
central Colombia, Diana Matallana, a neuropsychologist at the
Pontifical Xavierian University in Bogotá, still seems unable to
believe where she is. “Five years ago, you could not come here,” she
says. “It’s like a symbol of the hardest part of the conflict.”
The Meta region, where Vista Hermosa lies, was one of the areas
abandoned by the Colombian military in the 1990s and left to be
governed alternately by paramilitary groups and guerrillas. It was a
fraught arrangement. The guerrillas helped to develop infrastructure
but were swift to kill suspected informants. The paramilitaries
tended to be more ruthless, torturing suspected spies and leaving
bodies across the doorsteps of elementary schools. Both sides dealt
heavily in the cocaine trade and kidnapped thousands of people for
ransom — including Matallana’s brother.
The disarmament and rehabilitation campaign is run by Colombia’s
Reincorporation and Normalization Agency (ARN) in Bogotá. The ARN
had been established years earlier, and it has since facilitated the
reintegration of some 20,000 paramilitaries and guerrillas who left
the conflict independently or as part of a separate peace agreement.
The 26 transit zones that former fighters are entering offer
amenities such as education and health care, and help to provide at
least a measure of protection for the ex-combatants, who are
regularly targeted by former enemies, FARC dissidents and civilians.
After completing a programme, ex-combatants can receive ID cards
that allow them to live and work legally in the country. The
prospect of their return doesn’t thrill some local residents of
Vista Hermosa. A road sign in Spanish that reads “Together, peace
and life after the conflict are possible” has been pelted with pink
paintballs. “Someone disagrees,” remarks one of the researchers.
Matallana and Carlos Gómez, a psychiatrist at Xavierian, are
planning to launch a 10- to 20-year study following more than 2,000
people in Vista Hermosa, civilians and ex-combatants alike. “We are
planning for the first time — in Colombia and the world — to learn
what things help for reconciliation,” Gómez says.
The team intends to measure factors such as neuro-development in
children, social cognition and emotional regulation in adults, and
all participants’ mental health to aid the reintegration process. In
a pilot project funded by philanthropic foundations, they have
surveyed 200 civilians, plus representatives for 150 ex-combatants
living in a transit zone just 3 hours away. “We need to have good
data to see how it works, and how we could make interventions
rapidly if we see the process is not coming well,” Gómez says.
It’s been hard for researchers here and elsewhere to study whether
such programmes can prevent combatants from returning to crime,
largely because it is often impossible to track the outcomes of
people who go through them. “We just assume it has an effect, and we
have no other choice,” says Enzo Nussio, a political scientist at
the Swiss Federal Institute of Technology in Zurich.
Yet Nussio and others are hopeful about Colombia’s prospects. It has
many more resources to devote to the effort than countries, such as
Burundi and Sudan, which have taken on similar efforts with little
The former combatants, meanwhile, face a mix of challenges — some
familiar and some new. Like veterans from other conflicts, many find
it difficult to be around people who do not understand the
experience of combat, says Thomas Elbert, a psychologist at the
University of Konstanz in Germany. They may reach out to others who
have lived in violence, which can be dangerous in a place such as
Colombia, where drug traffickers and other armed groups still
Colombia itself poses some unique challenges, Gómez says. Unlike
those fighting civil wars in many other places, Colombia’s guerrilla
fighters are not driven by race or religion, but by political
ideology. Reprogramming their hearts and minds might call for
strategies different from those used for other radicalized
militants, war criminals or serial killers, and no one knows what
those strategies should be.
Gustavo Tovar, president of Vista Hermosa’s municipal council, fears
that his town — and the country — isn’t ready for the wave of
ex-combatants. “Colombia is in the middle of this metamorphosis,” he
says. “We went into it without knowing what we are doing.”
Weight of the past
West of Meta lies Valle del Cauca, a mostly flat agricultural
region surrounded by mountains. Here, in a luxurious hotel
overlooking vineyards and sugarcane fields, former FARC
commander Juan Carlos Sánchez is watching videos on a laptop.
Designed for research, they feature different types of
altercation: an argument between two people, someone getting
bumped by a chair, one person stabbing another in the back with
Sánchez joined the guerrillas in 1998 while living in Meta. It
was not entirely by choice, he says. When the Colombian military
abandoned the region, the FARC became the de facto government.
The guerrillas persuaded locals to arm themselves in case the
paramilitaries and government returned, telling them that this
was the only way to protect their families. Eventually, Sánchez
joined the group officially.
At first, he says, the guerrillas did not attack civilians —
they just schooled their recruits in politics and warfare
skills. But over time, the FARC became more violent and
suspicious of others. “From the day I entered the organization
to the day I deserted, I always had questions,” he says — about
himself, his comrades and the people giving orders,
particularly, their willingness to kill former allies. But
Sánchez kept quiet because questioning orders would get him
killed. Instead, he rose in the ranks, eventually leading some
By 2005, he had become more disillusioned with the FARC. A list
of suspected informants he had been ordered to kill included 12-
and 13-year-old children, as well as 2 people whom he knew from
his childhood. He ordered his troops to do it — something that
haunts him to this day. “It is you that carries the weight,” he
Then, a few years later, the guerrillas convicted his girlfriend
— also a FARC member — of espionage. Sánchez made plans to run
away with her, but was discovered and had to flee on his own. He
later learnt that she had been executed.
For three years, Sánchez lived in hiding in Meta, seeing enemies
everywhere. “I lived in constant worry,” he says. Eventually, a
friend told him about the government rehabilitation programme,
and he joined. He moved to Valle del Cauca and now clears fields
for a living. He has seen a psychologist, and has begun reading
the Bible. “Between the two, I’ve found a way to forgive myself
and to forgive others,” he says.
In the hotel, Sánchez watches the videos of altercations
interspersed with a series of questions, probing whether the
imagery bothers him, or whether a responsible party should be
punished. Then he tries to identify the emotions on a series of
“We’re looking at what kind of mistakes they make,” says Agustín
Ibáñez, a neuroscientist at Favaloro University in Buenos Aires,
Argentina, who is administering the test, a mock run of the type
he has given to around 350 Colombian ex-combatants. Ibáñez aims
to discern how isolation from society and exposure to violence
might have impaired their emotional processing and moral
judgement. Ex-combatants — FARC and paramilitary alike — tend to
have trouble distinguishing between emotions, especially fear
and anger. Although it is unclear whether these effects persist
outside the lab, Ibáñez and his team worry that emotional
problems could make life even harder for the former fighters, as
they have for ex-combatants elsewhere.
He and Eduar Herrera, a cognitive psychologist at Icesi
University in Cali, began this line of research in 2014, working
with a group of paramilitaries in jail for war crimes. They had
killed an average of 33 people each, and some were responsible
for massacring hundreds.
“The first time, we were very scared,” Ibáñez recalls. The
ex-combatants weren’t handcuffed, and met the researchers face
to face. “You have the feeling they can kill everyone if they
In 2017, the researchers found that a key characteristic of
ex-combatants is how they judge the morality of an action1. Most participants would condemn an attempted poisoning, for
instance, even if it failed to kill the target. But Ibáñez’s
group has found that ex-combatants are less likely to condemn
someone for a failed murder attempt, reasoning that if the
victim didn’t die, there was no harm done. At the same time,
they are more likely to want to punish people for harm that is
clearly accidental. By their logic, the outcome is more
important than the intention.
Trujillo has also found striking differences in her
participants. In a study of 624 ex-guerrillas and
ex-paramilitaries2, she and her colleagues found that the ability to empathize
fell into 3 clusters: 22% of ex-combatants functioned much like
people who haven’t experienced violence; 32% had the ability to
recognize pain or misfortune in others but weren’t as affected
by it; and the rest could neither recognize feelings such as
emotional distress in others, nor empathize with them.
The researchers wonder whether these ex-combatants — who
demobilized voluntarily — are similar to the 6,800 FARC fighters
who entered the reincorporation programme as part of the 2016
treaty, many on orders from their commanders. Unlike Sánchez,
many are still steadfastly ideological. Oscar Vega, for example,
a slight, intense former FARC commander who lives in the transit
zone near Vista Hermosa, steers almost every conversation around
to ways in which Colombia’s government and educational system
hurt people. He still lives for the cause. “Our documents and
our ideology say that we have to take control of power either
through arms or through a political way,” he says.
Trujillo is comparing various types of therapy to determine how
best to help the ex-combatants improve their performance in
tests of empathy3. And she and her colleagues are using electroencephalography
(EEG) to monitor ex-combatants’ brain activity, hoping to learn
how they process information4. In unpublished research, the team has found that former
fighters are quicker to recognize faces than are civilians —
even though they are slower to identify the emotions on them.
They are also better at performing memory tasks that are
accompanied by violent imagery such as blood or corpses. People
whom the researchers identified as victims of violence show the
opposite pattern — such imagery disturbs their concentration and
slows their responses. The researchers think that the
ex-combatants’ neurocircuitry has adapted to react faster to
Trujillo’s group advises the Medellín branch of the ARN in its
effort to rehabilitate ex-combatants. But trying to use science
to inform policy can feel like sculpting with dry sand.
“Research has been very complicated because it’s a very new
topic, not just for Colombia but for cognitive and social
neuroscience literature,” she says.
Researchers also worry that the government could lose patience.
“If you cannot find something strong to demonstrate what’s going
on, you cannot propose a solution,” says José David López, an
engineer who works with Trujillo interpreting EEG data at the
University of Antioquia. “They need it now, not in ten years.”
A battle within
Viviana Misas’s wrist bears the name of the baby she miscarried
while living with the National Liberation Army (ELN) — another
left-wing guerrilla group that is still active in Colombia. Misas
joined the ELN at 15 years old to get away from her family, and grew
to love the ideology and the companionship it provided. But then she
fell down during a difficult march and was injured, losing her
pregnancy. Her companions abandoned her, and she ended up in the
hospital for a long time. Distrusting her loyalty after that, a
fellow combatant — her closest friend — betrayed Misas to the
Colombian army. She was captured and agreed to demobilize.
Like Sánchez, she can’t return to her home in Medellín, for fear
that the ELN would kill her as a traitor. Although Misas enjoys her
work as a tour guide in Valle del Cauca, depression keeps her from
pursuing her dreams. “I wish that when I get sad, I would be like a
normal person that just gets sad for a little moment and doesn’t
have thoughts as strange as mine,” she says. She hasn’t seen any
psychotherapists, but her dog provides some solace, as does
religion. Still, her thoughts turn dark — perhaps, she says, the
real reason she joined the group was because she hoped to be killed.
“How can I let go of those thoughts?” she asks.
According to the ARN’s data, more than 90% of ex-combatants in the
programme have a psychosocial problem, such as post-traumatic stress
disorder or anxiety. Regional ARN coordinator Juan Fernando Vélez
says that mental health is one of his top priorities in working with
them. Trujillo’s data, he says, persuaded his office to create a
special reintegration track for people with psychiatric problems.
“We cannot give to society an individual that is not adjusted,” he
Joshua Mitrotti, who directed the ARN for three years before
resigning in March, says that the agency’s programmes are based on
efforts in Central America in the 1990s, which provided vocational
training and education for armed groups. Psychosocial support is an
integral component, he says.
The ARN’s programme for guerrillas and paramilitaries who
demobilized voluntarily included 30 months’ worth of psychosocial
services, from about 300 psychologists and 65 social workers, on
average. So far, 20,490 people have completed the reintegration
process, and the ARN says that more than 70% have successfully
But with tens of thousands of ex-combatants in Colombia, there are
simply not enough skilled mental-health practitioners to provide
basic care, much less intensive cognitive therapy. As a result, some
worry that the reintegration programme might be providing poor
treatment. “It’s not that they are doing things wrong, but they are
incomplete,” Herrera says.
One challenge is the difficulty of providing treatment to adults who
might not have completed elementary school and cannot read, a skill
required for some common therapies.
Mitrotti says that the ARN has been adjusting the approaches to make
them more appropriate. According to the ARN, 30% of the people
coming for psychosocial services last year did so without any
monetary inducement (ex-combatants often receive a stipend for
participating in programmes). “They are coming not because they’re
paid but because they believe they need the support of our
professionals,” Mitrotti says.
But help for the newly demobilized FARC members has been slow in
coming. Andres Restrepo, a sociologist who works in a transit zone
in Caqueta, says that the FARC ex-combatants there are not receiving
any mental-health care at all. Restrepo says the ARN has promised
that 6 psychologists will come to the region, but that even that
wouldn’t be sufficient for the 1,000 ex-combatants and their
families living there, now.
Restrepo fears that if these individuals are not psychologically
stable, the rejection from society — including their own families —
could drive them back into violence. “Nobody helped them imagine a
life without weapons,” he says.
An uncertain future
In Piñalito, a tiny, dusty town of fluorescent wooden houses on the
outskirts of Vista Hermosa, civilians are still getting accustomed
to peace. “It’s great — there are no dead people,” says Carlos
Garcia, an elderly retired shopkeeper. He remembers hearing regular
gunfire right outside his door as the FARC fought the
Now the streets are quiet and people linger at outside cafes. A few
are missing legs; Colombia has one of the highest rates of landmine
casualties in the world, and Meta is one of the most heavily mined
regions. Against the backdrop of a government crackdown on the
cocaine trade, falling oil prices and rising fears that peace is
temporary, the people of Piñalito seem to have few prospects for the
“Nobody helped them imagine a life without weapons.”
And the peace agreement itself is threatened. This month, Colombia
will hold its presidential election, and the key issue is whether to
renegotiate the deal to make it less favourable for the FARC. Many
of the guerrillas, meanwhile, are losing faith in the process. Some
of the transit zones where FARC members were required to live for a
time still have no running water or sanitation. And farming and
vocational-development programmes have been slow to take off. Across
the country, more than half of the guerrillas have left the zones,
opting to take their chances in a society that is unsafe for them.
Since the agreement, hundreds of former FARC members have been
As ex-combatants re-enter society or retreat into the jungle,
experts worry about the stigma they carry — of being affiliated with
the FARC and of mental illness. Matallana hopes that one of the
things her research can do is to show the public how trauma affects
ex-combatants and civilians alike.
Resources are in short supply and the problem is unimaginably
complex, says Vélez. Ultimately, he says, Colombia’s success rests
on the will of its people and their ability to make peace with the
past. “There are no magical formulas,” he says. “The only thing we
need to understand is that everybody needs — deserves — a second