Traumatic Brain Injury (tbi)

Running head:

Traumatic Brain Injury (TBI)

Traumatic Brain Injury (TBI) Gregory Cordes General Psychology PSY7310 Physiological Psychology Winter 2009 [email protected]

Abstract This paper will discuss the nature of Traumatic Brain Injury (TBI), the scope of the disorder, the types of TBI, and how psychologists can divide these types into 2 classes. In addition, this paper will discuss the cognitive, emotional, and physiological consequences of TBI in the context of the type and class. There will be some discussion on detection of TBI, early determination, first aid, and future research and work, as well as the developmental variables. Traumatic Brain Injury (TBI) Introduction What is TBI? Traumatic Brain Injury (TBI) is a physical insult to the brain as a result of an external physical force which produces an altered or diminished state of consciousness (Brain Injury Association of New Jersey, 2008). The consequences of TBI are typically an impairment of physical or cognitive abilities and may result in disturbance of emotional and behavioral functioning. The cognitive consequences of TBI include reduced ability to process information, organizational problems, trouble concentrating, poor judgment, memory loss, and difficulty starting activities. The physical consequences of TBI include muscle spasticity, seizures, headaches, fatigue, and balance problems. An observer may expect to see mood swings, depression, impulsivity, anxiety, and agitation as the emotional consequences of TBI (BIANJ, 2008). TBI has 2 cousins that mimic some symptoms of TBI, but are categorically different. While the symptoms may be similar, observers should not confuse TBI with Acquired Brain Injury (ABI) as a result of anoxia, aneurysms, encephalitis, stroke, metabolic disorders, and meningitis or brain tumors (BIANJ, 2008). Mild Brain Injury usually comes in the form of a mild concussion (BIANJ, n.d.). In sports, concussion is the most frequent cause of brain injury, loss of consciousness is not necessary for all concussions, people are a greater risk with each successive concussion, and multiple concussions may result in a life time of consequences (BIANJ, n.d.). The incidence of TBI is enormous. In the United States, more than 1.4 million people sustain TBI annually, only a sixth seeks help (BIANJ, 2008). This paper will discuss the significance of the 1.4 million victims later on. More than 50,000 people die annually from a TBI related injury. Approximately 80,000 to 90,000 experience a long term disability after receiving a TBI. In fact, more people sustain TBIs than breast cancer, spinal cord injury, multiple sclerosis, and HIV/AIDS combined. Many times, healthcare professions do not attribute behavioral issues, physical impairment, and cognitive deficits to TBI. Public recognition of TBI is low, despite the large number of injuries, mental healthcare professionals call it "the silent

epidemic" (BIANJ, 2008). There are several leading causes of TBI. The American population sustains 28% of TBIs in falls, 20% to motor vehicle accidents, 19% in struck by events, and 11% in assaults (Brain Injury Association of America, 2006). The majority of military TBIs are a result of blast injury. This paper will discuss blast injury later in the paper. The Centers for Disease Control estimate approximately 5.3 million Americans live with a TBI (BIAA, 2006). This number may grossly underestimate the number of TBIs, with 1.4 TBIs a year (BIANJ, 2008) - the actual numbers could be as high as 70 million over the last 50 years. Typically, males are 1.5 times more likely to sustain a TBI (BIAA, 2006). Children ages 0 to 4 and young adults ages 15 to 19 are the highest at risk groups. The group with the highest death rates for TBIs is African Americans. Americans hospitalize 235,000 people each year for TBI, at a cost of 60 billion dollars. Of this 235,000, 40% require outpatient assistance after release. The most common service needs are problem solving and memory, emotional upsets and managing stress, controlling temper, and job skill improvement (BIAA, 2006). Discussion What are the types of TBI? Psychologists can map the types of TBI across several dimensions, against the effected area, force of the blow, nature of the assault, general symptoms, and the physical consequences of the shock (BIAA, n.d.). General symptoms of the TBI may include loss of bladder and bowel control, tingling or body numbness, slurred speech, difficulty swallowing and speaking, irrational and emotional responses, thinking skills problems, ear ringing, confusion, headache, lethargy, and vomiting. In addition, the victim may have increase blood pressure with slow breathing. Other symptoms include slow pulse, paralysis, coma, respiratory failure, blurred and double vision, inability to tolerate light, eye movement loss, blindness, dilated eyes, lost consciousness, and spinal and intracranial fluid loss (BIAA, n.d.). There are several categories in the nature of the insult. Diffused Axonal Injury (DAI) occurs when the brain cannot physically keep up with the movement of the skull (BIAA, n.d.). Typically, the cause of a DAI is strong rotational forces applied to the head as might occur in an automobile accident. These rotational forces tend to stretch and tear nerve tissue across the brain. When the brain's nerve tissue is torn, it interrupts the brain's ability to communicate between its various structures and disturbs its chemical processes. In addition, a DAI is likely to release brain chemicals creating additional injury. DAI is especially dangerous because the inside of the skull is rough, rotational shifting the skull, but not the brain is likely to cause widespread lacerations across the surface of the brain. DAI causes widespread permanent damage that can result in coma or death (BIAA, n.d.). Another type of TBI is concussion (BIAA, n.d.). Concussion can come in many forms including gun shot wounds, a violent shaking, whiplash, or head blow. It is the most frequent type of TBI. Concussion can come in the form of an open or closed head injury. The sudden impact of the concussion causes cranial nerves and blood vessels to stretch. The stretching of blood vessels can cause them to tear resulting in a blood clot that can be fatal. Brain bleeding, skull fracture, or swelling may be present, and their need not be a loss of consciousness. Interestingly, physicians cannot always detect concussion in a Computerized Tomography (CT) (BIAA, n.d.). Contusion is another type of TBI. A contusion is the result of a focal impact on the brain (BIAA, n.d.). The focal impact results in a bruise and subsequent bleeding. In many cases, large contusions require surgical removal. A coup - contrecoup injury is similar to contusion. But, the force of the blow is strong enough to cause a contusion on the opposite side of the brain. This is the result of the brain, which is essentially floating in intracranial fluid, slamming against the opposite side of the skull (BIAA, n.d.). Multiple assaults to the brain are another type of TBI. Recurrent Traumatic Brain Injury (RTBI) or Second Impact Syndrome (SIS) occurs when a TBI sustains a second TBI before the first TBI has healed (BIAA, n.d.).

This insult is likely to cause widespread damage and brain swelling and can cause death quickly. Increased muscle tone, muscular spasms, unstable emotions, difficulty learning and thinking as well as hallucinations are the long-term effects symptomatic of SIS. Physicians and Psychologists can characterize penetration injury as the contamination of the brain by a foreign object (BIAA, n.d.). A penetration injury such as a bullet wound or knife forces fragments of hair boned and skin into the skull (BIAA, n.d.). A “through and through” TBI occurs when an object penetrates and then exits the skull. This results in shearing, stretching, rupture, and penetration injury. If the object is unable to penetrate the skull, it will begin to ricochet causing additional damage. Of all causes of TBI, firearms are the largest. Similar to DAI, is shaken baby syndrome (BIAA, n.d.). Mental health professionals characterize shaken baby syndrome as the violent shaking of a young child or baby where whiplash like motion results in TBI (BIAA, n.d.). In this scenario, the skull ruptures and bleeds as blood vessels are torn. This causes brain tissue to swell and compress damaging the cells. Shaken baby syndrome can result in a lifelong disability, seizures, death, and coma (BIAA, n.d.). One of the last of these TBI types on this axis of the map is locked syndrome. While rare, locked in syndrome sufferers can only move their eyes, but they retain their ability to think and remain conscious (BIAA, n.d.). Typically they use eye blinking and vertical eye movements to communicate and manage environmental controls (BIAA, n.d.). The final type on this axis is blast injury. Blast injury occurs when a complex over-pressurized wave passes through the cranium (Defense Veterans Brain Injury Center, n.d.). The brain essentially floats in intracranial fluid, and fluid filled cavities are especially susceptible to blast injury (Elsayed, 1997; Mayorga, 1997). Victims of blast injury experience slower thinking, depression, irritability, sleep disturbances, headaches, and decreased attention/concentration, and memory (DVBIC, n.d.). One characteristic of a blast injury TBI are small voids filled with intracranial fluid within structures in the brain that are normally solid (Glasser, 2007). One explanation for these voids is cavitation. Cavitation is a mechanical effect that when a solid object moves through a liquid medium at a high speed the fluid is unable to move out of the way fast enough creating tiny vacuums behind the trailing edge of the solid object. An observer can see this when the blade of a propeller on a boat turns and produces characteristic voids that appear like bubbles. Of all TBIs, blast injury is the most aggressive because the assault comes at about the speed of sound. It may be possible that the speed of the shock produces cavitation in the brain as it passes through nerve tissue and tearing it, then allowing low viscosity intracranial fluid to fill the cavitation before the high viscosity nerve tissue can fill a void. Another axis of TBI is open and closed wound. Open head injuries occur when the skull is penetrated. The brain may swell, but because it is no longer contained may result in squeezing nerve tissue. Open head injuries are more likely to be penetration injuries, where a foreign object lodges its self in brain tissue. Without the protection of the scalp and skull, the victim’s brain is subject to infection. On the other hand, with a closed head injury the brain may still swell, but was no place to expand, an intracranial increase of pressure on the brain tissues results in further damage. In an attempt to relieve pressure, brain tissue may attempt to force its way through the eye sockets resulting in pressure on the optic nerve. Whole Brain versus Localized Injury Up to now, this paper has discussed the types of TBI from the perspective of a physical insult to the brain. It is possible to divide these insults into two classes, whole brain and local. Whole brain insults would include DAI, shaken baby syndrome, blast, and concussion because damage as a result of these injuries would be widespread. Contusion, Coup-Countrecoup, and penetration injuries fall

under the category of local brain damage. The psychological, emotional, and physiological complications are dependent on the site of the injury because psychologists know what brain functions occur in specific locations. Locked in syndrome and second impact syndrome can fall under either class depending upon the nature of the injury. This is not to say whole brain injuries might not already contained some localized injuries. For example, it would be reasonable to suggest that someone with a blast injury at the anterior of the brain might and also have contusions to the occipital lobe. The cause might be as a result of the brain smashing against the rear wall of the skull striking the rough surface and compressing, a cause likely to result in lesions and hematomas. The consequences of whole brain injuries are much more likely to be hard to predict because the entire brain has come under some kind of assault. Complicating the matter, the nature of the assault is likely to make the consequences more difficult to assess. For example, a high energy blast injury might produce different results than a low energy DAI. Further complicating the matter is the angularity and rotation of the injury, making generalized assumptions in terms of predicting outcomes more difficult, in DAI for example. Predictions for localized injuries outcomes are more predictable. This part of the paper discusses what localized brain injury is likely to cause what type of emotional, cognitive, and physiological results. The frontal lobe, or cerebral cortex, which an observer can locate right under the forehead at the far most anterior of the brain is responsible for consciousness, the initiation of activity, executive control, emotional response, habit memory, motor activities, and language expression (Lehr, 2009; Carlson 2007). The likely consequence of this damage to the cerebral cortex would be loss of the ability to sequence multitasks, paralysis in local areas of the body, fought persistence, and inability to focus, abrupt mood changes, and changes in personality and behavior. In addition, the healthcare provider should expect problem solving difficulties. The healthcare provider might expect to see difficulty in language expression or Broca's Aphasia, if there is sufficient damage to the frontal lobe to effect Broca's area (Lehr, 2009; Carlson, 2007). Damage to the parietal lobe presents a different set of problems. The parietal lobe, near the top and back of the head is responsible for touch perception, visual attention, voluntary movements, and the manipulation of objects (Lehr, 2009; Carlson, 2007). Damage to this area of the brain might result in object confusion - anomia, noun in verbal amnesia - agraphia, difficulty locating words in writing - alexia, reading problems - dyscalculia, difficulty with mathematics - apraxia, lack of physical self awareness and their surrounding space - as well as difficulty distinguishing right from left, drawing objects, hand-eye coordination, and lack of ability to focus visual attention (Lehr, 2009; Carlson, 2007). Healthcare providers could expect other visual problems with damage to the occipital lobe. The occipital lobe, located at the extreme back of the head or most posterior region is responsible for vision (Lehr, 2009; Carlson, 2007). Healthcare providers can expect damage to this area of the brain to result in visual field cuts, defective vision - color agnosia, and inability to identify colors - and movement agnosia, and inability to detect movement of an object - as well as word blindness, hallucinations, and drawing recognition problems (Lehr, 2009; Carlson, 2007). Temporal lobe damage produces its own list of problems. The temporal lobes, just above the ears, are responsible for or visual perceptions, memory acquisition, and most importantly problems hearing and understanding what an individual hears (Lehr, 2009; Carlson, 2007). Damage to the temporal lobes can result in prosopagnosia, an inability to recognize faces Wernicke's aphasia, an inability to understand spoken words - categorization, difficulty categorizing objects - as well as selective attention disturbances between what an individual sees and hears - an inability to identify or verbalize objects - an increase in interference with long term memory and short-term memory loss problems (Lehr, 2009; Carlson, 2007). Damage to the brain stem is extremely

dangerous. The brain stem, leading to the spinal cord, lies deep within the brain (Lehr, 2009; Carlson, 2007). The brain stem is responsible for startle response, swallowing, reflexes, heart rate, hearing and seeing - controls the autonomic nervous system which includes temperature control, digestion, blood pressure, and sweating - and the vestibular system - as well as sense of balance. Typical problems a healthcare provider might observe with brain stem damage would include dysphagia, breathing and swallowing difficulties, vertigo, nausea and dizziness, as well as perception/organization difficulties with the environment, and problems with movement and balance. Likewise, the cerebellum is also responsible for some aspects of balance (Lehr, 2009; Carlson, 2007). An observer can locate the cerebellum at the base of the brain (Lehr, 2009; Carlson, 2007). It is responsible for reflex motor acts, equilibrium, voluntary movement, and balance. Damage to the cerebellum would result in difficulty with fine movements, an inability to walk, loss of ability to reach out and touch objects, tremors, slurred speech, dizziness, and difficulty in making rapid movements (Lehr, 2009; Carlson, 2007). Developmental Effects of TBI The risks and consequences of TBI are developmentally dependant. Most of this paper addresses the effects of TBI on adults, special consideration exist for infants, children, adolescents, and older adults. This paper has already discussed infants – children between the ages of 0 to 4 years old are in one of the highest risk groups for TBI (BIAA, 2006). Shaken baby syndrome, as the name implies, only applies to babies. The detection of a TBI is further complicated by the fact that between the ages of 0 to 4 years old, children are either poor communicators or do not speak at all. To make matters worst, CT cannot always detect TBIs (BIAA. N.d.) provided a skull fracture or brain bleeding is not present as already discussed (RSNA, 2009). Perhaps the best way of detecting TBI in young children is looking for abnormal developmental changes, developmental changes that occur rapidly in early childhood (Broderick & Blewitt, 2006). There are a number of differences between TBI school age children and their peers. In assessing TBI students an observer is likely to find several deficits, some cognitive, in attention span, impulsivity, distractibility, poor organizational skills, frustration tolerance, information overload, social judgment errors, integration skills, abstract thinking, problem-solving as well as poor processing information, and reduced performance in relation to ability level (BIANJ, 2007; The National Dissemination Center of Children with Disabilities, n.d.). An observer is likely to find the same deficits with learning disabilities, however – in addition to these deficits an onlooker would also expect to find additional problems. These problems might include a wider variation in performance skills, greater variation in abilities, changes in learning styles before and after injury, deficits in new learning while retaining old declarative memory, memory deficits would be more pronounced, social contact would be altered, the inconsistency of performance would be exaggerated, lack of self control, a broad range of inappropriate behaviors, and a lack of insight of the problems they are facing. There would be emotional changes as well. These changes might include problems regulating mood, and lack of self control. Again, an observer would be likely to see these behaviors to occur in children with learning disabilities, however – children with TBI would exhibit additional behaviors. These behaviors might include overreaction to change – overreaction to sensory stimulation including light, temperature, movement, and noise – deficits and awareness of these problems – lack of recognition of cause and effect relations – inhibition – confusion – and less reaction to rewards and punishments (BIANJ, 2007; TNCCD, n.d.). It is also important to note that it would be very easy to confuse a learning disability with localized TBI because of the limited number of deficits produced by that class of injuries as already discussed. It is also important to note that a single one of these behaviors would not

automatically constitute a TBI, but clusters would be indicative. TBI in adolescence pose there own set of problems. As stated earlier, adolescents between the ages of 15 to 19 are among the highest at risk groups (BIAA, 2006). It is at about this time, adolescents begin to enter the workforce (Lash, 2000). TBI adolescents face special challenges with regard to accurately completing tasks, paying attention, establishing a routine, remembering directions, appropriate response to feedback, task switching, working independently, accommodating changes in routines, readiness to redo tasks, evaluating the quality of their work, using work materials and language appropriately, and maintaining a separation between work and personal issues (Lash, 2000). There are many things educators can do to prepare students for this adjustment. Lash (2000) recommends a number of academic strategies to prepare adolescence students for these challenges. These attention strategies include reducing distractions, dividing work into small sections, presenting information and asking students to summarize, alert students with cue words using a non-verbal cueing method. For memory enhancement, again summarize information – maintain assignment sheets – use self reminders such as calendars, Post-it notes, and assignment books – educate students on chunking information – teach mental rehearsal – show students how to incorporate relevant knowledge with prior learning. To improve the organizational skills, provide students with more time to review, write checklists, prepare daily routine schedules, review the schedule with the student, provide written cues to organize an activity, drill sequencing material, prepare outlines, use color coding materials, and teach self planning. To develop following direction skills, provide both written and oral instructions, then repeat the instructions to the teacher, highlighting or underline specific parts of written or directed assignments, converting complex directions into simple steps, teaching self checking, and slowing the pace of learning (Lash, 2000). Let us turn our attention to older adults. While older adults do not fall in a high risk group for TBI, Americans ages 75 and over are at risk for hospitalizations and death as a result of a TBI (U.S. Department of Health and Human Services Centers for Disease Control and Prevention, 2008) Symptoms of TBI in older adults include repeated nausea or vomiting – worsening headaches that do not go away – seizures or convulsions – difficulty waking from sleep – dilation in both or one pupil – slurred speech – loss of coordination - numbness or weakness in legs or arms – increased restlessness – agitation - or confusion. In addition, some medications such as blood thinners can exacerbate the likelihood of an older adult receiving a TBI, even if the blow to the head is small (USDHHSCDCP, 2008). Early Determination, First Aid, and Future Research of TBI There are several early-warning sign of TBI. These initial symptoms present themselves as severe facial or head bleeding, ear or nose bleeding, severe headache, level of consciousness changes that occur more than a few seconds at a time, discoloration behind or below the eyes, termination of breathing, confusion, difficulties with balance, leg or arm weakness, unequal pupil size, vomiting, slurred speed, and seizures (Mayo Clinic, 2008). The Mayo Clinic suggests several steps for the initial stages of TBI. The Mayo Clinic (2008) recommends keeping the individual still, but lying vertically in a dark room with shoulders and head elevated, stop bleeding by applying firm pressure to the site of the wound with a sterile or clean cloth unless the help giver believes the skull is fractured, and observe changes in alertness and breathing. Current research by the National Institute of Health (2008) suggests that for adults lowering the body’s internal core temperature to 91.4 degrees Fahrenheit (33.0 degrees C) within 8 hours of injury reduces or reverses much of the effect of a TBI. There are several new research trends the National Institute of Health is pursuing. The National Institute of Health (2008) is evaluating the effectiveness of lowering body temperature of children with TBI as a means of lowering intracranial

pressure and creating an increase in blood flow. Another area of current research is the use of stem cells to replace or repair damaged nerve tissue. The National Institute of Health is also pursuing improved rehabilitation programs for those individuals who already have TBI (NIH, 2008). Conclusion The scope of TBI in our society is dramatic. There are 8 types of the injury including DAI, concussion, contusion, coup-contrecoup, RTBI, penetration injury, shaken baby syndrome, and blast injury. Brain injuries come in 2 different classes, whole and local brain injuries. DAI, concussion, shaken baby syndrome, and blast injury would fall in the whole brain damage. On the other hand, contusion, coup-contrecoup, and penetration injury would fall under the class of local brain injury. RTBI and locked in syndrome could fall into either group, depending on the nature of the pre-existing injury and the more recent one. However, it would fall in the local brain damage in only one of 4 possible outcomes, when both the previous and most resent damage are both local injuries. Local brain injures produce are more predictable in terms of consequences. Localized brain injuries allow us to take advantage of what psychology already knows about brain structure and what likely consequences would develop as a result of damage to those sites. TBI is developmentally dependant - it effects infants, children, adolescents, adults, and older adults differently. Infant TBI is difficult to detect because of communication problems, TBI children learn at a slower pace the non-TBI students and in some cases slower with than children with learning disabilities (BIANJ, 2007). Teachers must employ different educational strategies for children with TBI. Adolescents with TBI must prepare to enter the job market - instructors can help here too (BIANJ, 2007). Older adults are more vulnerable to the most dangerous aspects of a TBI assault, death and hospitalization because of frailty and medication (USDHHSCDCP, 2008). There are early warning signs for TBI just after trauma. There are a number of warning signs in the early stages of TBI, and the appropriate first-aid can limit and reverse potential damage. Research on TBI is ongoing, and focuses on new therapies as well as new applications of existing techniques on different developmental groups. For example, determining if lowering body temperature in children is as effective as lowering body temperature in adults as a means of limiting and reversing TBI (NIH, 2008). References Agamanolis, D. P. (2006). Traumatic brain injury and increased intracranial pressure. Retrieved on February 2, 2009 from http://neuropathology.neoucom.edu/chapter4/chapter4aSubduralepidural.html. American Speech - Language - Hearing Association. (2009). Right Hemisphere Brain Damage. Retrieved on February 10, 2009 from http://www.asha.org/public/speech/disorders/RightBrainDamage.htm. Brain Injury Association of America. (2006). Facts about traumatic brain injury. Retrieved on February 1, 2009 from http://www.biausa.org/elements/aboutbi/factsheets/factsaboutbi_2008.pdf. Brain Injury Association of America. (n.d.). Types of traumatic brain injury. Retrieved on February 1, 2009 from http://www.biausa.org/Pages/types_of_brain_injury.html. Brain Injury Association of New Jersey. (2008). The brain controls everything. Retrieved on February 1, 2009 from http://www.bianj.org/learn. Brain Injury Association of New Jersey. (2007). Brain injury: A guide for educators. Retrieve on February 1, 2009 from http://vizedhtmlcontent.next.ecollege.com/ec/courses/31631/CRS - CCPDCEO 3159991/Brain_Injury,_A_Guide_for_Educators.pdf. Brain Injury Association of New Jersey. (n.d.) What is concussion? Retrieved on February 1, 2009 from http://www.sportsconcussion.com/. Broderick, P.C. & Blewitt, P. (2006). The life span: Human development for helping

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