Concussions and the Rate of Depression in Professional Athletes

Running head: CONCUSSIONS AND THE RATE OF DEPRESSION/SUICIDE
Concussions and the Rate of Depression/Suicide in Professional Athletes
Lauren A. Rolek
Immaculata University

CONCUSSIONS AND THE RATE OF DEPRESSION/SUICIDE 2
Abstract
The purpose of this literature review is to examine if there is a link between concussions and the
rate of depression and suicide in professional athletes. The athletes that were focused on for the
purpose of the paper were National Football Leagues and National Hockey League players. In
order to get a fuller understanding of depression and concussions, early research dating back to
Ancient Greece was examined. Revisiting the earlier research also made it easy to pin-point
when the relationship between concussions and depression began to form. Three famous case
studies on depression, concussions, and CTE were also examined in order to relate the material
to the research question. The famous case studies are Freud’s Mourning and Melancholia,
Guidotti’s Phineas Gage and His Frontal Lobe, and Omalu et al.’s Chronic Traumatic
Encephalopathy in a National Football League Player: Part II. Lastly, current research studies
on the links between concussions and the rate of depression and suicide in athletes, as well as the
onset of dementia, were examined. The research found that athletes who suffered from three or
more concussions were three times more likely to be depressed, twice as likely to develop a mild
cognitive impairment, and have an increased risk for suicide or suicidal ideation. Common
treatments for concussion were briefly explored to see how it could benefit the athlete.

Introduction
Over the past 15 years, there has been a growing cause of alarm within the world of
sports- the number of professional athletes who have committed suicide. As the cases of suicide
increase, so does the public interest on what could be causing this epidemic. One proposed
theory is that the amount of concussions these athletes come in contact with may be affecting the
rate of depression and suicide. This literature review will revisit the history behind depression,
concussions,and the relationship between the two, reflect on famous research studies, and review
current research studies in an attempt to answer what is causing the increase in the rate of suicide
and depression.
Needfor Study
One of the major reasons that the link between concussions and depression/suicide should
be examined is the alarming statistics. A 2012 study reported that one in ten Americans suffer
from depression. Worldwide, it is believed that over 121 million people have some form of
depression (“Unhappiness by the Numbers,” n.d.). Along with high rates of depression, there has
been high spike in the rates of suicide in America within the past 15 years. The suicide rates in
America have risen 21.5% from 2000 to 2012. As of 2013, the suicide rate in America was 12.6
suicides being committed per 100,000 people (“Facts and Figures,” n.d.). These numbers are
reflected in the athletic world. Over the past few years, the suicide rate in professional athletes
has risen (Gagne, 2011). Since the early 2000’s, there have been numerous cases of professional
athletes who have committed suicide. In the past 10 years alone, five National Hockey League
(NHL) players, eight National Football League (NFL players), and eight Major League Baseball
(MLB) players who have committed suicide (“The Sheet: Remembering Those We Lost,” 2011;

Carlson, 2014; “Baseball Suicides,” n.d.). The following literature review will examine the
influence, if any, that concussions have on the rates of depression and suicide, as well as the
onset of dementia in professional athletes by answering the following questions:
1. 1. How prevalent are concussions in professional sports?
2. Do concussions affect the rate of depression and suicide in professional athletes?
3. 3. Do concussions affect the onset of dementia in professional athletes?
History
History of Depression
Depression is a mental illness that has been noted throughout various periods of time.
One of the earliest recordings of depression came in the 1850’s, when Falret and Baillager
proposed the concept of “melancholia,” which bears similar resemblances to depression (Trede
et al., 2005, p. 157). Almost 80 years later, Robert Burton added his own theories to melancholia,
or melancholy. Burton believed that melancholy could be treated through means such as music,
healthy sleep and diet, and/or talking with friends (Burton, 1932). One of the more accurate
descriptions of depression came for psychologist Emil Kraepelin. Kraepelin wrote various texts
on what he referred to as “manic-depressive insanity (Trede et al., 2005).” In his work, Kraepelin
named five different features of depression. Some of the features, such as impaired attention,
guilt, anxious/depressive moods are similar to current symptoms of depression (Trede et al.,
2005). In today’s world, depression is defined as “as serious medical condition in which a person
feels very sad, hopeless, unimportant and is often unable to live life in a normal way” (Merriam-
Webster, n.d.). Common symptoms of depression that are recognized today include anger or
irritability, changes in appetite, changes in sleep, feelings of helplessness or hopelessness, loss of

energy, loss of interest in favorite activities, and reckless behavior (Smith, Saisan, & Segal,
2015).
History of Concussions
The most common brain injury that athletes face are concussions. Concussions are “...a
jarring injury of the brain resulting in the disturbance of cerebral function (Merriam-Webster,
n.d.)”. The most common symptoms of a concussion are feeling sluggish, not feeling right,
headaches, nausea, dizziness, sensitivity to light and sound, and confusion or memory problems
(“Concussion Signs and Symptoms, 2015). The term concussion was first used sometime
between 460-377 B.C. by Greek physician, Hippocrates. Hippocrates wrote extensively about the
brain injury and how it appeared to leave one without the ability to hear, see, or speak
(Echemendia, 2006, p. 21). The first detailed discussion of concussions came from another
physician, Rhazes. Rhazes was the first person who was able to distinguish concussions from
other severe head injuries. Rhazes new insights on concussions greatly contributed to the modern
understanding of concussions (Echemendia, 2006, p. 21). In the 18th century, concussions began
to be brought up in discussions in terms of clinical symptoms and neuropathological changes.
Scientist also began to question whether the mechanisms of concussions were structural or
functional (Echemendia, 2006, p. 23). The most recent information on concussions has come in
the 20th century, when researchers began noticing the dangerous frequency in which football
players were suffering from concussion and other head injuries (Echemendia, 2006, p. 24).
Repeated concussions appear to be a common occurrence in the NFL. A research study
done by Kerr et al. found that out of 1044 former NFL players found that 25.8% suffered from
one or two concussions (2012, p. 2208). The study also found that 19.5% of the players suffered
three or four concussions, while 12.9% reported suffering between five and nine and 6.8%

reported suffering from 10 or over (Kerr et al., 2012, p. 2208). The amount of concussions
reported by the depressed athletes may be slightly inaccurate, which means that concussions may
be even more prevalent in the NFL than originally thought (Kerr et al., 2012, p. 2210). The
amount of concussion in the NFL is worrisome to many, as the concussions can lead to
damaging conditions for the athlete, such a chronic traumatic encephalopathy or depression.
History of Chronic Traumatic Encephalopathy
Chronic traumatic Encephalopathy (CTE) is “...a progressive degenerative disease of the
brain found in athletes, and others, with a history of repetitive brain trauma…(“What is CTE,”
n.d.).” There is a possibility that CTE can be brought on by a single traumatic brain injury, but
no current research has a definite answer on the matter (McKee et al., 2009). The brain trauma
that leads to CTE includes both asymptomatic subconcussive hits and symptomatic concussions.
CTE can begin to affect the brain anywhere between months or decades after the persons
sustains the traumatic injury (“What is CTE,” n.d.). There are three stages of CTE, which have
been distinguished by Corsellis, Bruton, and Freeman-Browne. In the first stage of CTE, the
person suffering from the disease faces affective disturbances and psychotic symptoms (McKee
et al., 2009). In the second stage, the disease manifests to erratic behavior, memory loss, and
social instability. The person may also begin to display the initial signs of Parkinsonism (McKee
et al., 2009). In the third and final stage of CTE, the symptoms progress into the full-fledged
symptoms of Parkinsonism, as well as dementia. Additional symptoms of CTE may include
confusion, deterioration in speech, dizziness, headaches, poor judgement, impeded speech, and
the slowing of muscular movements (McKee et al., 2009). While there is currently no known
cure for CTE, some researchers believe that athletes following the proper return-to-play

guidelines after suffering from a concussion can help to reduce their risk of developing CTE
(McKee et al., 2009).
The issues of concussions in the professional sporting world first began to be noticed in
the 1994. Interest in the issue started around January of 1994, when NFL quarterback Troy
Aikman was hospitalized after being concussed during a game. Months later, fullback Merril
Hoge retired from the league after suffering from numerous concussions (Ezell, 2013). During
that 1994 season, the NFL started the Mild Traumatic Brain Injury (MTBI) committee. Despite
what happened to Aikman and Hoge, both the MTBI committee and the commissioner of the
league denied that there was a concussion problem within the league (Ezell, 2013). Five years
after the
commissioner dismissed the concussion problem, a shocking claim was made by a former player.
In April of 1999, Mike Webster came out with a claim that his participation in the sport caused
him to have dementia (Ezell, 2013). Months following Webster’s claim, the NFL Retirement
Board ruled that the head injuries he sustained during his career left him permanently disabled.
In spite of the recent cases with Aikman, Hoge, and Webster, the MTBI claimed that concussions
and other serious brain injuries were rare occurrences (Ezell, 2013). The following year, Dr.
Barry Jordan and Dr. Julian Bailes presented their research finding that concussions may lead to
neurological problems. Two years later, a second major break-through study came through when
Dr. Bennet Omalu examined Webster’s brain after he passed away (Ezell, 2013). During his
examination, Omalu found signs of a brain disease in Webster’s brain, known as Chronic
Traumatic Encephalopathy (CTE). Omalu’s findings were revolutionary, as this was the first
time that CTE had been found in an NFL player (Ezell, 2013). Omalu went on to discover CTE
in the brain matter of two other deceased players. The players were Justin Strzelczyk, who

complained of depression before his death, and Terry Long, who passed away from suicide
(Ezell, 2013). In 2005 and 2006, Omalu published his research findings on Webster and Long’s
brains, despite any backlash received from the NFL or the MTBI committee. Omalu cited how
both players seemed to suffer from depression and receiving multiple concussions during their
career (Ezell, 2013). Though the NFL was not very receptive of Dr. Omalu or his studies, his
research studies opened the gate for other scientist and psychologist to examine the link between
concussions and depression in athletes. Since Omalu’s, numerous studies on CTE have been
published and to this day, the research is still being continued (Ezell, 2013).
Famous Research Cases
Sigmund Freud on Depression
One of the most famous early works on depression is Sigmund Freud’s paper, Mourning
and Melancholia. In his work, Freud compares the psychological condition of melancholia and
compares it to mourning. Freud describes melancholia as having distinguishing symptoms such
as cessation of interest in the outside world, inhibition of all activity, a lowering of one’s self-
regard, and profoundly painful dejection (Freud & Strachey, 1955, p. 244). Freud believed that
these characteristics, aside from lowering one’s self-regard, were also symptoms of mourning.
Freud also believed that melancholy and mourning had another similarity- the reason that they
occurred (Freud & Strachey, 1955, p. 244). Just as mourning is brought on by the loss of a loved
one, Freud thought that melancholia was brought on by the loss of a loved object. He
hypothesized that the person suffering from melancholia may not realize the loss on a conscious
level, which may leave them wondering why they’re experiencing these feelings of sadness
(Freud & Strachey, 1955, pp. 244-245). Finally, Freud believed that loss of a loved object during
melancholia could lead to the loss of one’s ego. The loss of ego is a result of the lowering of

one’s self-regard, as it leaves the ego impoverished (Freud & Strachey, 1955, p. 246). The loss
experienced during melancholia may be similar to the losses that athletes face when suffering
from a concussion. Just as melancholia results in the loss of one’s ego, the athlete may feel as if
they lost a part of him or herself during or after their concussion,
The Case of Phineas Gage
One of the most well-known studies on brain injury came from the case of Phineas Gage.
Phineas Gage was working as railroad foreman when he had an unfortunate accident while
working. One of the iron tamping bars that Gage was working with shot out of place and ended
up penetrating through the left, bottom side of his head (Guidotti, 2012, p. 249). The bar then
passed completely through the top of his head and landed almost 80 feet away. During the
accident, Gage lost the frontal lobe of his brain. Fortunately, Gage survived and was treated by
Doctor John Martyn Harlow (Guidotti, 2012, p. 249). Gage faced a few complications during his
surgery. Gage was left exhausted as a result of profuse bleeding and had a couple of other
complications, such as abscess formation and non-healing bone fragments (Mitchell, Humphries,
Jalali, & Gopinath, 2012, p. 266). Despite the various complications and his traumatic injury,
Gage was reported as being conscious during surgery and was able to walk within months
(Guidotti, 2012, p. 249). While Gage made a remarkable physical recovery, the surgery had a
lasting impact on his personality. Once known as a hardworking, reliable man, Gage became
disorganized and stubborn after his brain injury (Guidotti, 2012, p. 249-250). The changes that
Gage experienced are well-known for showing how damage to or the removal of the frontal lobe
can affect one’s behavior (Guidotti, 2012, p. 249-250). The changes in personality that Gage
experienced are a common symptom that athletes report after suffering from concussions. In one
research study, a former NHL player who suffered from from numerous concussion reported that

he “became a different person” after the concussions (Caron, Bloom, Johnston, & Sabiston,,
2013, p. 171).
Dr. Bennet Omalu and CTE
As previously mentioned, Dr. Bennet Omalu is credited for being the first doctor to
discover CTE in an NFL players’ brain. Along with this, Omalu and his colleagues published
one of the first and most famous case studies on CTE and the links between concussions in
depression. In this case study, Omalu performed a psychological autopsy exam on a 45 year old
man. The man was a former NFL player who played for four years in college and eight years in
the National Football League (Omalu et al., 2006, p. 1807). The player was reported to have
been suffered from numerous concussions during his career and displayed changes in both his
personality and mood within years after retiring from the NFL. The player also had a past history
with suicide attempts, with the first attempt being made in 1992 (Omalu et al., 2006, p. 1087).
Following the first suicide attempt, the player began psychotherapy and was later diagnosed as
having an adjustment disorder with depressive mood. The player subsequently made various
other suicide attempts before taking his own life in 2005 (Omalu et al., 2006, p. 1087). The
autopsy on the players brain revealed a “....mild neuronal dropout in the frontal, parietal, and
temporal lobes…”as well as in the globus pallidus (Omalu et al., 2006, p. 1088). Omalu’s
autopsy was also able to confirm that the former NFL player did have CTE. Omalu notes that
both the player in this study and a player in a second study who suffered from CTE had
similarities in their cases- both players sustained numerous concussions during their careers and
both suffered from depression (Omalu et al., pp. 1090-1091). Omalu and his colleagues research
confirmed something that many researchers were wondering- that there may be a link between
concussions and depression in athletes after all.

Investigations Pertaining to Research Questions
ResearchPertaining to Concussions
The Center for Disease Control and Prevention (CDC) found that an estimated 1.6-3.8
million concussion occur each year due to sports or recreational activities (Didehbani, Munro
Cullum, Mansinghani, Conover, & Hart, 2013, p. 418). The NFL, in particular, has high
concussion rate. In particular, the concussion rate in the NFL is higher than the majority of other
contact sports (Kerr, Marshall, Harding, & Guskiewicz, 2012, p.2206). It is estimated that there
are 0.41 concussion per every NFL game. The players who are at most risk for these concussion
are defensive backs, quarterbacks, tight ends, and wide receivers (Kerr et al., 2012, p. 2206). In
the Canadian Junior league, there are approximately “...21.5 concussions per 1000 athlete
exposures (Caron et al, 2013, p. 168).(Didehbani, 2013, p. 422). Although concussions are often
dismissed in the athletic world as “part of the job,” they can have serious side-effects for the
athletes who sustain them.
ResearchPertaining to Link between Concussions and Depression/Suicide
Though it is something that is not often discussed publically, depression appears to
becoming a common occurrence in the world of professional sports. One research study
estimates that around 10-12% of retired NFL players will experience major depression within
their lifetime and one in four of the players will either experience or be diagnosed with the
disorder (Weir, Jackson, & Sonnega, 2009, p. 31). Along with this, a study conducted by
Guskiewicz et al. (as cited in Didehbani et al., 2013) found that retired athletes have a higher
tendency to experience a lifetime of depression than the average male (p. 419). Another research
study found that NFL players who suffered one or two concussions were 1.5 times more likely to
suffer from depression (Kerr et al., 2012, p. 2207). The more concussion that a player sustains

during their career, the higher chance they develop to major depressive disorder. One research
study NFL players who suffered three or more concussions were three times more likely to
suffer from depression than NFL who had no history of concussions (Guskiewicz, as cited in
Didehbani et al., 2013, p. 419). These statistics were reaffirmed in a research study done by
Didehbani et al., which found found that the higher number of concussions an athlete suffered,
the more likely there were to report as having feelings of depression. Didehbani et al.’s (2013)
study also found a correlation between the Cognitive factor of Beck’s Depression Inventory,
which suggest the athletes may often face the cognitive symptoms of depression. These
cognitive symptoms include critical self-evaluations and feelings of sadness and/or guilt
(Didehbani et al., 2013, p. 422). One hypothesis for why concussions may cause depression for
the athletes is the biochemical changes that the brain lesions may bring on.
It is believed that brain lesions in concussed athletes bring about a biochemical change “...that
increases the number of excitatory neurotransmitters and result in neuron loss and cell death
(Kerr et al., 2013, p. 2207).” The loss of neurons may then bring on on the onset of depression
in the athletes (Kerr et al., 2012, p. 2207). Unfortunately, this change has not only been found in
football players, but in hockey players as well.
Though majority of the concussion studies have been focused on professional football
players, professional hockey players have recently been brought into the discussion as well. NHL
players often face more severe post-concussion symptoms than other athletes, as well as miss
extensive playing time. While it is know that these NHL players with concussions face various
physical symptoms, such as dizziness or fatigue, they are at risk for facing psychological
symptoms as well.(Caron et al., 2013, p. 168). The link between concussions and depression in
NHL players may not come as a shock to many scientist. This is because functional magnetic

resonance imaging (fMRI) in concussed athletes resemble the neural responses of those in a
depressed individual (Caron et al., 2013, p. 168). The resemblance found between the two may
explain the psychological impact that concussions leave on NHL players. The psychological
symptoms that concussed NHL players may face include anxiety, depression, and isolation. In
some cases, the player may even have suicidal ideation (Caron et al., 2013, p. 168).In a study
conducted by Caron, Bloom, Johnston, and Sabiston, three of the former NHL players who were
interviewed discussed suffering from depression as a result of the concussion they suffered
during their career. It is notable that two of the players admitted described their experience as a
“deep depression” (Caron et al., 2013, p. 173). The language used by the players seems to
indicate the severity of the depression they face. This was also shown when players in the study
also confessed to contemplating suicide within months after the concussions (Caron et al., 2013.
p. 173).
Just as concussions increase the risk of depression in professional athletes, they appear to
increase the athlete’s risk of suicide as well. One of the reasons for this is that concussed athletes
are prone to having risk factors for both suicide and suicidal ideation. On of the most major
potential risk factor for suicide or suicidal ideation in the general population is chronic pain
(Iverson, 2014, p. 2). Athlete’s who suffered from multiple concussions often face chronic pain
as a result of symptoms such as headaches and sensitivity to light and sound (“Concussion Signs
and Symptoms,” 2015). The pain alone that these athletes face could make them more prone to
suffer from suicidal ideation. Aside from chronic pain, athletes who have a history with
concussions have another risk factor for suicide: depression. Players who suffered from three or
four concussion are three times more likely to experience depression than those who have no
history with concussions (Didehbani et al., 2013, p. 419). As concussed athletes are prone to

suffer from both chronic pain and depression, their risk for suicidal ideation or suicide could be
increased compared to the general population’s risk (Iverson, 2014, p. 2). One research study
found that the prevalence of suicide in football players with CTE is significantly higher than that
of others who have CTE. Within the same study, the football players who were diagnosed with
CTE made up for almost 80% of the case studies on suicide (Maroon et al., 2015, p. 11). In
another case study that interviewed with five former NHL players who retired due to
concussions, three of the players admitted to who had thoughts of suicide (Caron et al., 2013).
ResearchPertaining to Link between Concussions and Dementia
Along with depression, it has also been theorized that there is a “dose response” between
head injuries and an increased risk of dementia (Kerr et al., 2012 p. 2206). Scientist have found
in past research that the numerous concussions and head trauma that boxers experience may lead
to the development of dementia pugilistica (Guskiewicz et al., 2005, p. 720). Dementia
pugilistica is a branch of CTE and typically “...manifests itself as dementia…(“Dementia
Pugilistica,” n.d.).” The symptoms the disease include confusion, problems with movement and
speech, and slowed movements (“Dementia Puglistica,” n.d.). Similar manifest of dementia can
be found in football players who suffered from numerous concussions. One research study found
that retired football players who received three or more concussions during their career were
two-times more likely to be diagnosed with mild cognitive impairment that players who
sustained only one or two concussions. The players also were found to have five-times the risk of
being diagnosed with mild cognitive impairment than players who never had a concussion
(Guskiewicz et al., 2005, p. 723). The results from the research study also show that there may is
a possible connection between repeated concussions and dementia-related syndromes. These

syndromes can include granulovacuolar degeneration,loss of neurons, and reductions in synaptic
density (Guskiewicz et al., 2006, p. 723).
While links have been made between repeated concussions and dementia, no strong
correlation has been found with repeated head injuries and the diagnosis of Alzheimer’s Disease.
It is notable, however, that the onset appears to begin earlier in NFL players than it does in the
general population (Reider, 2012, p. 2197). Concussive hits appear to be the largest threat for
athletes when it comes to mild cognitive impairment, as there is little to no link between
subconcussive hits and dementia. A study conducted on soccer players found that there was no
significant link between a longer career of “heading the ball” (hitting the ball with one’s head)
and testing positive for dementia. The study also found that any short-term or medium signs of
dementia or cognitive decline in the players may only be temporary (Vann Jones, Breakey, &
Evans, 2014, p. 3). Aside from dementia, a few other cognitive problems have been linked to
concussions. Various cognitive deficits such as deficits in episodic memory, naming, and word
finding were found to be more common in former NFL players who suffered from concussion
than those who have never sustained a concussion (Sethi, 2013). One survey found that 6% of
retired NFL players suffer from either, Alzheimer's Disease, dementia, or different memory-
related disease. Although there are not statistics for the rate of these diseases in other athletes,
various research articles show athletes who receive numerous concussions still have a moderate
risk of developing dementia and/or other cognitive deficits.
Treatments
NFL Guidelines
In 2007, the NFL created a new set of guidelines during a “Health and Safety” meeting.
The guidelines mandated that athletes get both a baseline test as well as a post-concussion

neuropsychological test. The athletes and their family members also received education on
concussion symptoms (Didehbani et al., 2013, p. 418). However, it wasn’t until that the NFL
created guidelines that prevented a player from practicing or playing the day they suffered from a
concussion. The new guideline also stated that the player cannot return until they are “...cleared
by team physician and an ‘independent neurological consultant’... (Didehbani et al., 2013, p.
418)”. Unfortunately, these physicians are often pressured to get the athlete to return to the field
as soon as possible instead of following protocol (Bal & Brenner, 2013). Despite the few flaws
the protocol may have, the baseline test can be very efficient in treating concussions.
Baseline Tests
One method that is used to test for concussions in athletes is the baseline test. A baseline
test is used to “assess an athlete’s balance and brain function. The brain function can include the
ability to pay attention or concentrate, how quickly the athlete is able to solve problems, and
learning and memory skills (“FAQs About Baseline Testing,” 2015). Along with assessing brain
function, baseline test can also be used to detect concussion symptoms in athletes. The baseline
test is often taken by athletes in the pre-season, when there is a low risk for injuries. This allows
for the baseline test to be used as a comparison to similar test if it is believed that the athlete may
have a concussion (“FAQs About Baseline Testing,” 2015).
ImPact Tests
One of the test that the baseline test can be compared to is the Immediate Post-
Concussion Assessment and Cognitive Testing, also known as the ImPact Test. The ImPact test
is a 25 minute, computerized test (“About ImPact,” n.d.). The ImPact test can be compared to an
athlete’s baseline test in order to asses potential damages that resulted from a concussion. The
test may also be used to determine when the athlete is safe to return to their sport (“About

ImPact,” n.d.). The ImPact test is made up of four components, which includes demographics
and health history, current concussion symptoms and conditions, baseline and post-injury
neurocognitive tests, and the graphic display of ImPact test scores (“About ImPact,” n.d.). Along
with the ImPact test, ImPact also has a five step concussion management model. The steps, in
order, include the preseason baseline testing and education, when a concussion is suspected,
post-injury testing and treatment plan, determining if the athlete is ready for non-contact activity,
and determining if the athlete is safe to return for play (“About ImPact,” n.d.). The management
model is beneficial to many athletes, as it is an “affordable” one. The management model can
also be used to help prevent the athlete from suffering from a long term injury or limit the risk of
one (“About ImPact,” n.d.).
Complications with Physical Treatments
Though baseline and impact tests are mostly beneficial for the athletes, there are some
complicating factors s well. Team physicians often run into a dilemma at work- taking care of
the athlete or getting them back on to the field as soon a possible (Bal & Brenner, 2013, p. 2061).
While the two can coincide at times, there are occasions when one has to be chosen over the
other. Unfortunately for the athletes, the physicians are often pressured to get them back on the
field. The pressure the team physicians face can sometimes lead to a hasty and ill-considered
decision being made. While the hasty decision may be “beneficial” to the team, it can be harmful
to the long-term health of the player (Bal & Brenner, 2013, p. 2061). A popular example of this
occurred with NFL quarterback Robert Griffin III. Griffin, who plays for the Washington
Redskins, was allowed to return to a playoff game despite a painfully obvious knee injury (Bal &
Brenner, 2013, p. 2061). Sadly, this is a common occurrence with professional sports, even with
serious injuries such as concussions or broken bones. The players often want to hide their injury

from coaches or medical staff so they could continue playing. In other cases, the athlete was
unaware that they were suffering from a concussion (Caron et al., 2013, p. 171). The pressure
both the medical staff and athletes face show a need for modifying how concussion, and other
injuries, are handled in professional sports. Until both the mental and physical health of the
athletes is put first, there will always be a “concussion problem” in professional sports.
Psychological Tests
As of now, there are no psychological tests that are given to athletes who suffer a concussion or
a brain injury. It is recommended by researchers in one study, however, that “professional
psychological counseling” should be provided to athletes while they are recovering from their
concussions or during retirement (Caron et al., 2013, p. 176).
Conclusion
Summary
The purpose of this literature review was to attempt to examine the impact that
concussions have on the rate of depression and suicide in athletes, if any. The first steps were to
revisit earlier history, famous studies, and recent studies on depression and concussions in the
athletic world in order to determine if there is a correlation between the two. After reviewing the
various research studies, it is clear that there is a link between concussions and the depression
rate in professional athletes. Professional athletes who suffered from three or four concussions
are three times as likely to suffer from depression than those who never received one, as well as
having a higher risk for suicidal ideation. Additionally, it was found that athletes who suffered
from three or more concussions are twice as likely to have mild cognitive impairment, including
dementia. The results of the literature review highlight the various issues that concussions can

cause for athletes and show the importance of finding proper prevention methods and treatments
for the athletes.
Implications for further research
As many studies on the link between concussions and depression are done on
professional football players, there may be difficulty in generalizing the results to athletes who
participate in other sports (Kerr et al., 2012, p. 2211). It is recommended that research is done on
concussions and head trauma in other professional sports leagues as well. Another factor to be
considered in further research is that the research studies focus on concussive hits.
Subconcussive hits may be another factor that plays a role in the rate of depression in athletes.
Further research is recommended to examine the effects of subconcussive hits on the athletes
(Kerr et al., 2012, p. 2211).

References
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