Evaluating the Limitations of Post-traumatic Amnesia as a Severity Scale Traumatic brain injuries (TBI) account to a third (30.5%) of all injury-related deaths in the U.S. with an estimated 1.7 million individuals sustaining TBI each year (Center for Disease Control and Prevention, 2010). Classifications of brain injury (e.g., mild, moderate and severe) is mostly done using the Glasgow coma scale (GCS) which has gained broad acceptance for the assessment of the severity of brain damage (Bauer & Fritz, 2004). Recent studies suggest that almost all patients with moderate or severe TBI have a period of recovery during which they are responsive but confused. This state is commonly referred to as the post-traumatic amnesia. Post-traumatic amnesia (PTA) is defined as “a failure of continuous memory” (Artiola et al., 1980; p.377). PTA is often cited as the best method for codifying the degree, level of recovery and outcome after a closed head injury (e.g., Artieola et al., 1980; Tate, Pfaff, & Jurjevic, 2000). PTA duration is a better indicator of outcome than early injury scales such as the GCS score (Richardson et al., 2009).This analysis will examine the limitations of the general PTA assessment scale, and investigate the benefits and limitations of both retrospective and prospective methods used to measure the duration of PTA. There is a frequent assumption that coma depth and extent, and PTA are concomitant—reflecting different facets of common mechanism (Wilson, Teasdale, Hadley, Wiedmann, & Lang, 1993). Researchers contend that when PTA and coma have been juxtaposed, their correlation has substantiated to be only moderately closer. Furthermore, they assert that previous studies exploring PTA and coma as predictors of outcome ... ... middle of paper ... ...reliable is it? http://www.ncbi.nlm.nih.gov/pmc/articles/PMC486693/pdf/jnnpsyc00001-0046.pdf McMillan, T.M., Jongen, E.L.M.M., Greenwood, and R.J. (1996). Assessment of post-traumatic amnesia after severe closed head injury: retrospective or prospective? Journal of Neurology, Neurosurgery, and Psychiatry, 60, 422-427 http://jnnp.bmj.com/content/60/4/422.full.pdf Tate, R. L., & Pfaff, A., Jurjevic, L. (2000)Resolution of disorientation and amnesia during post-traumatic amnesia. Journal of Neurology, Neurosurgery, and Psychiatry, 68, 178-185 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1736763/pdf/v068p00178.pdf Wilson J.T.L., Teasdale, G.M., Hadley, D.M., & Wiedmann, K.D., Lang, D. (2012). Post-traumatic amnesia: still a valuable yardstick. Journal of Neurology, Neurosurgery, and Psychiatry, 56, 198-201 http://jnnp.bmj.com/content/57/2/198.full.pdf
Hippocampus is a small, curved region, which exists in both hemispheres of the brain and plays a vital role in emotions, learning and acquisition of new information. It also contributes majorly to long term memory, which is permanent information stored in the brain. Although long term memory is the last information that can be forgotten, its impairment has become very common nowadays. The dysfunction is exemplified by many neurological disorders such as amnesia. There are two types of amnesia, anterograde and retrograde. Anterograde amnesia is inability in forming new information, while retrograde refers to the loss of the past memory. As suggested by Cipolotti and Bird (2006), hippocampus’s lesions are responsible for both types of amnesia. According to multiple trace theory, the author suggests that hippocampal region plays a major role in effective retrieving of episodic memory (Cipolotti and Bird, 2006). For example, patients with hippocampal damage show extensively ungraded retrograde amnesia (Cipolotti and Bird, 2006). They have a difficult time in retrieving information from their non-personal episodic events and autobiographical memory. However, this theory conflicts with standard model of consolidation. The difference between these theories suggests that researchers need to do more work to solve this controversy. Besides retrieving information, hippocampus is also important in obtaining new semantic information, as well as familiarity and recollection (Cipolotti and Bird, 2006). For instance, hippocampal amnesic patient V.C shows in ability to acquire new semantic knowledge such as vocabularies and factual concepts (Cipolotti and Bird, 2006). He is also unable to recognize and recall even...
The article “How Our Brains Make Memories” explains how traumatic events and the memories they hold can become forgotten over time. Karim Nader recalls the day that two planes slammed into the twin towers in New York City and like almost every person in the United States he had vivid and emotional memories of that day. However he knew better than to trust his recollections of that day because he was an expert on memory. He attended college at the University of Toronto and in 1996 joined the New York University lab of Joseph LeDoux, a neuroscientist who studies how emotions influence memory. Fast forward to 2003, Nader is now a neuroscientist at McGill University in Montreal, where he says “his memory of
Researchers and doctors had little information on the proper management and care of someone who sustained a concussion. There were 2,350 participants in this study, with each player being enrolled in any one of the Ivy League schools, University of Virginia, or University of Pittsburgh. Players who experienced a mild head injury during practice or a game were removed from the field to be examined and assessed for “cognitive and psychosocial dysfunction through the use of neuropsychological techniques and self-reported questionnaires up to four times after injury” (Barth, et al., 1989). In order for a player to be diagnosed with a mild head injury, he must have had either a head contact injury or a complete loss of consciousness that lasted under two minutes and displayed some sort of memory and/or attention deficient. The results of Barth’s study showed that there were 195 documented mild head injuries.
Understanding the reasoning behind amnesia and the hippocampus is of critical importance in neuroscience. Discussed by Cipolotti & Bird (2006), LTM impairments can lead to anterograde and retrograde amnesia if the medial temporal lobe (MTL) is damaged bilaterally. Specifically, the two most important types of LTM related to anterograde and retrograde amnesia are episodic and semantic memories. Conversely, many researchers have long debated the true functions of the hippocampus and have allowed two theories to emerge. The standard model of consolidation (SMC) assumes that the hippocampus is important in consolidating LTM, while the multiple trace theory (MTT) argues that information is encoded by specific memory traces by the hippocampus. These two theories help further explain the vast functions of the hippocampus. However, in regards to amnesic patients, the SMC has proven to be more widely accepted due to reported results implying that the hippocampus is important in consolidating LTM. In contrast, in anterograde patients, memories can be retrieved through recollection and familiarity. In fact, it has been proposed that the recol...
The injury is defined as a concussion when “it causes a change in mental status such as amnesia, disorientation, mental fogginess, confusion, nausea or vomiting, blurred vision or loss of consciousness.” (Mayo Clinic, n.d.)
Yates, Keith, et al. “Longitudinal Trajectories of Postconcussive Symptoms in Children With Mild Traumatic Brain Injuries and Their Relationship to Acute Clinical Status.” Pediatrics. 123.3 (2009) : 735-743. Web. 11 Apr. 2014.
...d disregard clues in a situation and fail to warn the person to use safety and caution (Pitman et al. 771). Research has shown that when affected by PTSD the hippocampal size has decreased between “0.0-0.5 which in percentage is 0-20%”, and that is a relatively large margin (Vilens and Sher 5). Vilens and Sher examined the reduction in the hippocampus by types of traumatic events and found that, “there seems a trend toward combat trauma resulting in larger changes, followed by childhood sexual abuse, accidents and interpersonal violence” (5). Studies on the amygdala have shown an increase in reaction to trauma related stimuli, and also play a role in the extent of the symptoms that one experiences (Pitman et al. 772). The prefrontal cortex, and corpus callosum both show lower volumes in people diagnosed with PTSD rather than those who are not (Vilens and Sher 5-6).
The effects of trauma on the functioning of the brain is an expanding subject of research and treatment. Trauma can change the chemistry of the brain and disrupt normal human functioning. Information in this section has been taken from the works of Judith Lewis Hermann, MD, Robert Scaer,
The only result from the testing consistent with a brain injury was the abnormal pupil response of the right eye (constriction) (Traumatic brain injury, 2015). The physical effects that could have pointed to a brain injury were the laceration to the right side of the gentleman’s head and the amount of blood loss. The complaints from the patient that may have insisted a brain injury included a severe headache, dizziness, and nausea (Traumatic brain injury, 2015).
... Shimamura, A. (1995). Susceptibility to memory interference effects following frontal lobe damage: findings from tests of paired- associate learning. Journal of Cognitive Neuroscience, 144-152.
management of real-world memory demands despite profound anterograde amnesia. Journal of Clinical & Experimental Neuropsychology, 30(8), 931-945.
Heinonen, H., Himanen, L., Isoniemi, H., Koponen, S., Portin, R., Taiminen, T. (2002). Axis 1 and 11 psychiatric disorders after traumatic brain injury: a 30-year follow-up study. Am J Psychiatry.159 (8): 1315-1321. (Medline).
All of the disorders in the Dissociative Disorders category need to be distinguished from conditions which are due to a General Medical Condition or the use of a Substance. Moreover, Dissociative Amnesia is within the diagnostic criteria for Dissociative Fugue, Dissociative Identity Disorder, Posttraumatic Stress Disorder, Acute Stress Disorder and Somatization Disorder; hence, an additional diagnosis of Dissociate Amnesia is not given. Dissociative Amnesia must be differentiated from Age-Related Cognitive Decline and nonpathological forms of amnesia.
Consequently, any major incidents that involve severe head injuries by force may cause retrograde amnesia. So, what is the significance of short and long-term memory storage in relation to amnesia? Through encoding and retrieval, we are able to experience external events; record them in our sensory memory; where they become encoded in our short-term memory; and then eventually encoded to our long-term memory—which is beneficial to our retrieving process. Again, imagine waking up one morning with a memory deficit, due to an incident that you have no idea occurred. How do you imagine you would react?
Stocchetti, N., Pagan, F., Calappi, E., Canavesi, K., Beretta, L., Citerio, G., … Colombo, A., (2004). Inaccurate early assessment of neurological severity in head injury. Journal of Neurotrauma, 21(9), 1131-1140. doi:10.1089/neu.2004.21.1131