Impact of Head Trauma on Brain and Behavior
Neuroscience research focuses on evaluating and understanding how the human brain functions and its development. However, there are certain factors that influence the human brain development and behaviors. Repetitive head trauma has significant impacts on the brain structure and function – which exposes a person to risk factors for long-term chronic trauma. Professional boxers and fighters experience lasting neurological effects that result from aggregated head trauma. This is because these athletes are constantly knocked on the head with varying intensities, in sparring and matches throughout their careers. Both amateurs and professional fighters are at risk of the neurobiological consequences linked to repetitive head injuries. The paper aims to examine the relationship between the extent of head traumas experienced, other environmental factors and the brain and behavioral changes and function that are experienced over time.
The target population includes boxers and fighters. Boxers and fighters act as human models that aid in studying the effects that repetitive head trauma has on the cognitive functioning and behaviors. Chronic traumatic encephalopathy (CTE) a term used to refer to brain degeneration due to consistent head trauma was reported among boxers in 1928. Individuals that are exposed to persistent head trauma have been found to be at high risk of neurodegenerative disorders including CTE. As a result, they may start exhibiting behavioral manifestations of CTE such as increased impulsiveness. Following these outcomes, various studies on boxers and fighters have defined the clinical characteristics of CTE, its association to the extent of experience in fighting, and a range of radiologic findings. Epidemiologic research that has analyzed the rate of neurological injuries in amateur and professional boxers and fighters reveal that the participants are at risk of getting acute brain injury that may in some cases lead to persistent neurologic damages (Bernick et al., 2013). Therefore, there is a need to investigate the relationship between the impact of head traumas and brain functioning among active professional and amateur fighters. Fight exposure is linked to increased levels of certain types of impulsiveness since it interferes with the volume of specific brain structures. Boxers and other fighters with high levels of exposure to head injuries have been found to have a significant reduction of thalamus, hippocampus and caudate brain structures.
To measure the cumulative head traumas that an individual is exposed to, certain factors are considered, including; the number of fights, the frequency of the fights annually, the number of knockouts (KOs) experienced and the duration a person has been fighting. Nonetheless, these variables tend to have a significant impact on the development of CTE in a person. Various studies have suggested that the effect of repetitive blows arising during sparring, and at times occur at the sub-concussive stage play a significant role in producing cumulative brain injury (Gardener et al., 2014). Moreover, KOs may show the severity of mild traumatic brain injury – while the number of KOs experienced may be tracked while others may not. The frequency in fighting is considered as a corresponding variable that needs to be evaluated – fighting frequently may interfere with the amount of time necessary for the brain injury to recover from previous injuries and may create a risk factor interrelates with the number of fights.
KO is the most common mild neurological injury that is experienced in boxing. This injury is characterized by unconsciousness which is as a result of a KO blow that is abrupt and brief when executed. The KO is a direct blow to the facial area which is accompanied by a torque rotational force that is transmitted directly to the brain – which further affects the cerebellum and brain stem. As a result, the injured person experiences dizziness and imbalance leading them to fall and lose consciousness. According to Gardener et al. (2014), depending on the degree of “knockouts” as an approach to measure neurologic injury may interfere with the actual rate of concussive head hits during boxing. Most studies refer to the KO as a fighter’s inability to stand upright for 10s – which may or may not lead to consciousness. However, considering the infrequency of KO during a fight, it may not be a primary reason that may lead to cognitive dysfunction in some boxers.
Human Brain Development and Problematic Behaviors Common among Boxers and Fighters
Concussions and sub-concussive knocks to the head are commonly associated with a chronic neurodegenerative condition such as CTE. Reports by the Centers for Disease Control and Prevention show that at least 1 million people that are in organized sports tend to experience a concussion annually (Bernick et al., 2013). Additionally, scientific research reveals that there are retired athletes that have passed away as a result of pathologically confirmed CTE (Manley et la., 2017). 51% of the injuries that boxers and fighters experience mainly occur in the facial area (Stiler et al., 2014). Amateur and professional boxers and fighters are likely to suffer from mild cognitive dysfunction after an injury. Some of the cognitive impairments that have been associated with head trauma among this population include; delayed memory, poor information processing, and verbal fluency, and slow spatial and mathematical processing (Hart et al., 2013). Neurologic injury among boxers and fighters are mainly as a result of the knockout punch which is associated with sub-concussive head blows.
Professional boxers and fighters with extensive fight history are more likely to experience brain injuries. Various studies found a relationship between the number of fights a person has engaged in and the progression of the neurologic, psychiatric and histopathological symptoms (Gardener et al., 2014). The neuropathological injury that occurs in many boxers includes; damage of the cavum septum pellucidum, cerebral scarring and atrophy, the degeneration of specific nuclear cells in the brain and cerebellar abnormalities (Manley et al., 2017). According to Manley et al. (2017), neurological trauma manifests in three ways among boxers, namely; acute neurologic injuries; persistent groggy states and the post-concussion syndrome; and chronic traumatic encephalopathy (CTE), which is popularly known as “punch-drunk syndrome” or “dementia pugilistica.”
Boxers and fighters do not suffer from chronic neurologic impairment after a single blow but are an effect of repetitive blows to the head. According to Gardener et al. (2014) the signs and symptoms of chronic neurologic impairment are noticeable after the cessation of a fighters career – thus, diagnosing chronic traumatic brain injury (CBTI) can be challenging. However, when a boxer shows signs of neurologic dysfunction later in their career, it must be examined to identify whether the neurologic effects are associated with boxing. Gardener et al., (2014) assert that the possibility of CTBI being associated with boxing in most cases is classified as conceivable, probable or improbable. Neurologic symptoms are often classified according to motor, cognitive, and behavioral factors. According to Bernick et al. (2013), the signs and symptoms of CTBI are detected at different times during a boxers life – thus they may be recognized during their career or after retirement. Therefore, the exact duration that boxers develop CTBI varies. However, fighters that are examined once they reach 5o years old have been identified to be at a higher risk of exhibiting neurological symptoms.
Impact of Head Trauma on Brain and Behavior