proximately 1,500 students, two students died by suicide within four
days.70 During an eighteen-day span that included the two completed
suicides, seven other students attempted suicide. What is the mecha-
nism underlying suicide clusters? Why are they relatively rare?
A possible explanation for the clustering of suicides is that
assortative relating is involved. Specifically, people who are vulnera-
ble to suicide may form friendships or romantic relationships with
each other based in part on shared suicide risk factors (e.g., sub-
stance abuse)—that is, they relate assortatively, not randomly. This
may have the effect of prearranging potential suicide clusters well in
advance of any stimulus that might activate the cluster. When im-
pinged upon by severe negative events, members of the cluster are at
increased risk for suicidality. Severe negative events would include,
but not be limited to, the suicidal behavior of one member of the
cluster. An array of other negative events could activate the cluster
as well.
According to this view, there are many potential clusters, but very
few clusters involve any actual suicidal behavior, in part because of
the “pulling together” effect noted earlier—if a member of a cluster
attempts or dies by suicide, it is a local tragedy that can pull people
together, increase belongingness, and buffer against suicidal behavior
by other members of the cluster. Increased belongingness is viewed
here as a braking mechanism in the phenomenon of suicide clusters.
This explanation is very challenging to test empirically, but I con-
ducted a study that attempted to do so. I showed that, consistent with
an assortative relating process, college roommates who chose to room together were more similar on a suicide index than were roommates
who were assigned to room together. Stress in the roommate rela-
tionship amplified similarity in roommates’ suicide levels. Results
were consistent with the view that shared stress simultaneously af-
fects the suicidality of people whose contiguity was prearranged by
an assortative relating process.71
What Do We Mean by Suicide? ● 167
Case reports are also consistent with this perspective. A cluster of
fourteen suicides among current patients of a London psychiatric
unit took place during a one-year period. Thirteen of the fourteen
patients suffered from severe, chronic mental illness (e.g., schizo-
phrenia), and most had ongoing therapeutic contact with the psychi-
atric unit. One factor in the development of this cluster was the pa-
tients’ valid perceptions that the future of the hospital was uncertain
and that their access to medical staff was decreasing and ultimately
threatened (a potential blow to the need to belong).72 Victims were
assortatively related (through contact with the same psychiatric unit)
based, at least in part, on shared suicide risk factors (e.g., chronic
mental illness). Vulnerable people were brought together (through
contact with the agency), were exposed to a belongingness threat
(potential for dissolution of the agency; lack of access to important
caregivers; for some, suicides of peers), and may not have been well
buffered by good social support (the chronically mentally ill often
have low social support; a main source of support may have been the
agency, which was threatened).
In a suicide pact among three adolescents, each was cocaine
dependent (a possible assortative factor for this cluster), and each
viewed the other two as the only source for a sense of belongingness.
When the three were threatened with dissolution by trouble with the
law and parents, their only source for belongingness was endangered.
The three decided on suicide.73
Another consideration regarding suicide clusters involves the ac-
quired ability to enact lethal self-injury, an emphasis of the theory
proposed in this book. It was noted earlier that courage and com-
petence regarding suicide may accrue ideationally through various
forms of mental practice, including aborted suicide attempts.74 It is
possible that members of suicide clusters may habituate to the idea
of suicide through frequent discussions of the topic with other mem-
bers of the cluster.
168 ● WHY PEOPLE DIE BY SUICIDE
This appears to occur on the disturbing “pro-suicide” website
alt.suicide.holiday (or ASH), where suicide is construed favorably
and where visitors are instructed on the best methods for suicide. For
example, regarding self-poisoning, the site makes these points: “Most
drugs cause vomiting. To help stop this, take one or two anti-hista-
mine tablets . . . about an hour before” and “Use a large airtight plas-
tic bag over your head, + something around your neck to hold it on.
This transforms a 90% certainty method into a 99%.” It is not dif-
ficult to see why many people feel rage and disgust at the activities of
this website.
As many as twenty-four completed suicides have been linked to
the site.75 In a quotation that illustrates assortative relating, Andrew
Kurtz, a visitor to the site, wrote in 1996, “I really like this site, be-
cause at least I know there are others out there who feel similar to
me. Sometimes I feel so alone, but I feel a little better reading other
people’s posts.” Kurtz died by self-inflicted gunshot wound a few
days after posting these words to the site. His post can also be viewed
as illustrating the merging of the need to belong and the wish for
death. Just as young people in Japan have linked up over the Internet
with the sole purpose of dying together, some people link up to this
site and feel a kind of belongingness in their suicidality.
In Chapter 1, I recounted a story from Tad Friend’s 2003 New
Yorker article of a young girl who took a $150 taxi ride to the Golden Gate Bridge and jumped to her death. She had been visiting a how-to
website about “effective” and “ineffective” suicide methods. The site
states that poison, drug overdose, and wrist cutting are rarely fatal,
and therefore recommends bridges, noting that “jumps from higher
than . . . 250 feet over water are almost always fatal.”
Pro-suicide group norms appear to attract people to the ASH
website and to encourage suicidality among visitors. Researchers
have experimentally evaluated the connection between group norms
and self-aggression. They used a self-aggression paradigm, which in-
volved self-administered shock during a task disguised as a reaction-
What Do We Mean by Suicide? ● 169
time game, with self-aggression defined by the intensity of shock
chosen. Their goal was to show that intensity of self-aggression is af-
fected by social group norms.76 In this research, high levels of self-ad-
ministered shock occurred when group norms were manipulated to
encourage self-aggression.
A tragic real-life version of this experiment occurred on January
12, 2003. Helen Kennedy reported in the New York Daily News on the death by overdose of a twenty-one-year-old man.77 The particularly
troubling aspect of his death was that many people witnessed it—he
died as a group of virtual onlookers observed him via his webcam. As
he took in more and more prescription and other drugs, comments
like “That’s not much. Eat more. I wanna see if you survive or if
you just black out” and “you should try to pass out in front of the
cam” were typed in by onlookers. Kennedy commented, “In the ma-
cho atmosphere of the druggie chat room, [the man who overdosed]
seemed to have something to prove.” The man’s brother agreed, stat-
ing “It seems like the group mentality really contributed to it,” add-
ing that the transcript of the incident was “disgusting.” Eventually,
some of the onlookers came to understand the gravity of the situa-
tion and tried to intervene, but could not, because they had no way
of finding out where the man was. He was found early in the after-
noon of the next day by his mother. Here, as in the example of the
ASH website, group mores normalizing risky behavior are encour-
aged, leading people to habituate to danger, which in turn leads to
self-inflicted death in some cases.
Suicides do occasionally cluster. This phenomenon may be un-
derstood in part in terms of assortative relating, thwarted belong-
ingness, and the accrual of suicide-related courage and competence
via encouragement from those with “pro-suicide” views.
I was concerned about these phenomena recently when I served as
a consultant to the city attorneys of St. Petersburg, Florida, who
wanted to block the rock band Hell On Earth from staging a show
featuring the public suicide of a terminally ill person. I emphasized
170 ● WHY PEOPLE DIE BY SUICIDE
two things in particular in my affidavit. First, I stated that there was
potential for vulnerable people who see a public suicide to become
further emboldened about their own plans for suicide—a vicarious
accrual of the ability to enact lethal self-injury. Second, the termi-
nally ill person had publicly committed to this incident, with plans
for the concert dependent on his or her suicide. The public nature of
the event may constrain the person from changing his or her mind.
In Chapter 2, it was noted that people often do change their minds
about suicide at the last minute. The city prevailed—the concert was
cancelled and a judge banned further such displays.
Indeed, publicizing suicide in careless ways can be a menace to
public health. In Tad Friend’s 2003 New Yorker article, he wrote of the frenzy that occurred as the 1,000th suicide from the Golden Gate
Bridge approached. He stated, “In 1995, as No. 1,000 approached, . . .
a local disk jockey went so far as to promise a case of Snapple to the
family of the victim.” Friend noted that the California Highway Pa-
trol halted its official count at 997, trying to quell attention to the
countdown.
Specific media guidelines have been developed to decrease the per-
nicious effects of inappropriately publicizing deaths by suicide. A
consortium of agencies, including the Centers for Disease Control
and Prevention, the National Institute of Mental Health, and the
American Association of Suicidology, came together to develop the
guidelines. The recommendations include not portraying the person
who died in romantic or heroic terms, reporting the death with few
details about method and location of death, and not conveying that
the suicide was an inexplicable act of an otherwise high-achieving
person. In general, the guidelines are intended to minimize identi-
fication with the person who died.
The model described in this book exceeds, I believe, the ability of
other frameworks to account for a diverse array of suicide-related
What Do We Mean by Suicide? ● 171
facts. Regarding facts as disparate as mass suicides in cults, the high
rate of suicide in Chinese women, the relative rarity of death by sui-
cide, and the clustering and contagion of suicide, the model provides
at least some explanatory power. In the next chapter, the applicability
and compatibility of the model to the genetics and neurobiology of
suicide, as well as the suicide risk factors of impulsivity, childhood
adversity, and mental disorders, will be taken up.
WHAT ROLES
DO GENETICS,
NEUROBIOLOGY, AND
MENTAL DISORDERS
PLAY IN SUICIDAL
BEHAVIOR?
5
Suicidal behavior runs in families, and this fact has to do with genet-
ics and neurobiology as well as genetically conferred personality traits
like impulsivity. Families share genes and much else. They also share
the family environment. Childhood adversity has been shown to be a
risk factor for later suicidal behavior. Genetics, neurobiology, per-
sonality, and early experience are each implicated in the development
of mental disorders, which in turn confer substantial risk for suicide.
In this chapter, I will review each of these topics as they link to sui-
cide and examine the compatibility and relevance of my model to
each of these topics.
In 1621, Robert Burton wrote in his massive Anatomy of Melan-
choly that black bile is suicide’s “shoeing horn.” Burton was remarkable—almost four hundred years ago, he anticipated a lot of key
findings about depression and suicide. Regarding suicide, he was
right that there does appear to be a “shoeing horn,” but black bile is
not it. If there is a “shoeing horn” for suicide, it is the serotonin
system.
Serotonin is a neurotransmitter that is key with regard to things
172
Genetics, Neurobiology, and Mental Disorders ● 173
like mood, sleep, and appetite. Understanding the role of seroto-
nin requires more, however, than just knowing about this neuro-
chemical. Serotonin is imbedded within a larger system, including
specific genes that code for things like the serotonin transporter
(which is responsible for “recycling” serotonin back up into neurons
after it is released into the gap between neurons, called the synapse)
and serotonin receptors (which receive serotonin from the synapse
and thus transmit a signal). Of course, the transporter and receptors
themselves, as well as serotonin itself, are important parts of the sys-
tem. All of these interact with one another in intricate ways. Despite
these complexities, the role of the system in suicide is becoming
clearer. Since serotonin-system genes may play a role in suicide, I will
start with a discussion of whether there is a genetic contribution in
general to suicide, and then focus specifically on serotonin-system
genes.
Genetics
In his 1936 book Man against Himself, Karl Menninger described
several families in which suicide was common. For example, he
wrote, “A highly regarded family contained five sons and two daugh-
ters; the oldest son killed himself at 35, the youngest developed a de-
pression and attempted suicide several times but finally died of other
causes at 30, a third brother killed himself in a manner similar to that
/>
of his older brother, still another brother shot himself to death, and
the oldest daughter took poison successfully at a party. Only two
children remain living of this entire family.”1 Incidentally, the gender
difference in death by suicide can be discerned in this example. Of
the brothers, 80 percent either died by or nearly died by suicide, as
compared to 50 percent of the sisters—hugely elevated rates in both
cases, but still, a gender effect of sorts.
Menninger continued, “There is no convincing scientific evidence
174 ● WHY PEOPLE DIE BY SUICIDE
that the suicidal impulse is hereditary and there is much psychoana-
lytic evidence to show that these cases of numerous suicides in one
family may be explained on a psychological basis.” The psychological
basis, he believed, was unconscious death wishes toward loved ones.
When a loved one dies by suicide, a relative’s unconscious death wish
is suddenly gratified, creating a wave of guilt that may culminate in
the relative’s suicide.
Menninger was working under an unfair disadvantage. Since the
time of his 1936 book, an enormous amount of work has shown the
clear involvement of genes in behavior in general and suicide in par-
ticular. Also since that time, psychoanalytic theories have not stood
up well to scientific scrutiny.
A family history of suicide appears to contribute about a twofold
increase in risk—a little more if there are multiple, close relatives
who have died by suicide; a little less if there are relatively few and
distant relatives. This rule of thumb can be very useful to people who
have lost a loved one to suicide. In fact, I have had visits and calls
from people around the United States about this very question.
Usually, the call or visit is from the wife of a man who has died by
suicide, wanting to know the genetic risk to her children. Anecdotes
like the family mentioned by Menninger in which five of seven sib-
lings died by suicide can make people understandably anxious. It is
often reassuring for people to hear that the risk for any given person
walking down the street is 1 out of 10,000, or .0001. A child whose
dad has died by suicide has a risk that is around 2 out of 10,000, or
.0002—no higher than 5 out of 10,000, or .0005, in any event. The
Why People Die By Suicide Page 22