Neurology and Trauma: Impact and Treatment Implications Damien Dowd, M.A. & Jocelyn Proulx, Ph.D.

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1 Neurology and Trauma: Impact and Treatment Implications Damien Dowd, M.A. & Jocelyn Proulx, Ph.D. Neurological Response to a Stressor Information from the senses goes to the thalamus which sends the information to other brain areas including the amygdala The hippocampus also sends information to the amygdala The amygdala sends information to the brainstem which generates a sympathetic system response that prepares the system for flight or fight The amygdala also sends messages to the hypothalamus which triggers a hormonal system response HPA Axis The hypothalamus which controls hormonal functioning releases corticotrophin-releasing hormone which triggers the pituitary gland to release beta-endorphins, which suppress pain, and adrenocorticotropic hormone which in turn triggers the release of cortisol from the adrenal gland Stress causes dysregulation of the HPA-Axis In the case of PTSD, beta-endorphins may continue to be released in response to flashbacks and intrusive memories This may lead to further PTSD symptoms such as avoiding situations or thoughts reminiscent of the trauma, emotional numbing, loss of interest in life and detachment from others There are also problems with the release of cortisol Cortisol affects learning, memory and emotions. (It also plays a role in metabolism by regulating the storage of glucose and effects the immune system by determining the length and strength of the inflammatory response to injury and by helping in the development of immune system cells) Typically in non-stressed individuals there is a higher production of cortisol during the morning and these levels gradually decrease during the day Extended production of cortisol can lead to a negative feeback loop - High levels in the system eventually lead to lowered production of

2 corticotrophin releasing hormone and adrenocorticotropin hormone and because adrenocorticotropin hormone leads to the release of cortisol, over time there is a consequent decrease in the production of cortisol This negative feedback loop may account for research showing that individuals with PTSD have lower than normal levels of cortisol in their system and individual with depression or who are dealing with current stressors or challenges have higher than normal levels of cortisol in their system What is not yet clear from the research is whether PTSD causes lower levels of cortisol production or if it is individuals with a genetic predisposition to having lower levels of cortisol that tend to develop PTSD - more research is needed Lower levels of cortisol may negatively affect a person's ability to process the event into long term memory, thus the memory remains as intense as when it first occurred. This may contribute to the flashbacks, intrusive memories, nightmares and fears associated with PTSD Higher levels of cortisol results in kindling - a process where the nervous system becoming sensitive to psychologically threatening stimuli thus generating an exaggerated response to even weak stimuli For individuals with PTSD this may mean that current stressors cause an exaggerated response especially if they are reminiscent of the trauma in any way The Hippocampus The hippocampus is involved in the formation of memories and in the regulation of stress Research has found less activity in the hippocampus of individuals with PTSD on learning and memory tasks There has also been a significant amount of research suggesting that the hippocampal region of individuals with PTSD is smaller, however there are also a number of studies that have not found this relationship It has been suggested that individuals who have a smaller hippocampus prior to a traumatic stressor may be more likely to develop PTSD or that it is only in cases of chronic PTSD that the hippocampal volume is affected - more research needed Among the effects of stress on the hippocampus are inhibiting the development of new neurons, the establishment of new memories and the

3 functioning of serotonin - a neurotransmitter that promotes sleep, temperature regulation and mood A degeneration of the hippocampus may lead to problems in learning and remembering new information, failure to remember general or details about the trauma, incomplete or no memory of the trauma, and dissociative episodes - all of which are potential symptoms of PTSD Medial Prefrontal Cortex The medial prefrontal cortex is involved in decision making, reasoning and judgement It suppresses or modifies the systemic arousal generated by the amygdala It can send messages that the situation is safe and thus there is no need for flight or fight response It can lead to a calmer, more strategic response to a threatening situation It also filters out irrelevant information, allowing the person to focus on what is important in their environment It is associated with processing of positive and negative emotions Impairment of the medial prefrontal cortex response means that the person is less able to generate effective coping strategies, self sooth and calm themselves. The amygdala response is less regulated and therefore the person may respond more intensely to fearful stimuli and may respond to a broader range of stimuli This may be responsible for symptoms of hyperarousal in PTSD, including exaggerated startle response, irritability, anger outbursts, hypervigilence, flashbacks, intrusive memories and misinterpretation of harmless stimuli as potential threats It may also mean that they are less able to discriminate between important and irrelevant information and therefore it becomes difficult to focus and pay attention This along with the inability to regulate amygdala response may lead to distracting thoughts and ideas that make it difficult to concentrate, follow instructions, reason, make sound judgements and decisions - all symptoms common in PTSD Reduced activity in the medial prefrontal cortex has been associated with a reduced ability to process positive emotions perhaps because unchecked, the amygdala focuses on negative emotions such as fear

4 In its efforts to try to modify the amygdala response, the cortex may be using its resources to focus on the negative and may have insufficient resources to entertain more positive thoughts Genetic Markers The literature suggests that there is a moderate heritability component to PTSD and that it is several genes rather than just one that contribute to a predisposition to developing this condition. Current research is exploring which genes are involved Family mental health is a risk factor - children whose parents developed PTSD were more likely to develop it as well Identical twins had a higher concordance rate for PTSD than fraternal twins Both genetics and environment are part of this risk factor Genetic predispositions may be related to cortical dysfunctions, smaller hippocampal regions, or an overly large cavum septum pellucidum This is a cavity between the right and left hemispheres of the brain that is present in infants but closes by adulthood in the majority of the population. Enlargements in this area have been associated with PTSD, schizophrenia and chronic brain trauma Genetic predispositions for problems with serotonin and to a lesser degree, dopamine have been implicated in the risk for PTSD Serotonin is associated with the regulation of mood, appetite, sleep patterns and temperature, and the regeneration of neurons - lower levels have been linked to depression and PTSD Dopamine is involved with arousal, voluntary movement, and conditioned fear responses - higher levels have been associated with PTSD Treatment 1) Drug Therapies Antidepressants such as SSRIs (paroxetine) have been effective in reducing the re-experiencing, avoidance, numbing and hyperarousal symptoms of PTSD - they are also effective in treating co-morbid depression and anxiety

5 Since these increase the amount of serotonin in the system, it has been suggested that they may help to regenerate neurons in the hippocampus. It has also been suggested that drugs that reduce corticotrophin-releasing hormone may reduce HPA axis dysfunction leading to hyperarousal. The problem with drug therapies is that they do not address the underlying causes of PTSD, perhaps accounting for the fact that more significant reduction in PTSD (and non-ptsd symptoms) symptoms have been found for other forms of therapy such as exposure therapy 2) CBT Most often applied therapies for trauma intervention Generated the most research and have demonstrated effectiveness in reducing PTSD and trauma related symptoms, more so than supportive therapies alone They address distorted, inaccurate and irrational beliefs and thoughts and replace them with more accurate and rational perceptions Traumatic memories are processed, relabelled and reorganized in a way that give the person a sense of meaning and control Adaptive coping mechanisms are learned 3) Exposure Therapy Is a form of CBT - for individual who avoid thinking about or talking about the trauma Individual gradually confronts trauma related information through talking and journaling Avoidance is reinforcing but does not resolve the trauma Facing their fears and memories of the traumatic event mean that these fears and memories lose their power to generate fear - individual finds out they no longer have the power to harm them in the present Associated with decreased symptoms such as avoidance and heightened arousal Reducing fear arousal may be necessary before individuals are asked to apply more cognitive strategies related to emotional regulation, logical thought, and functioning associate with CBT Lessening the fear response may allow the person to be calm enough to focus on more cognitive processes

6 Imagery rescripting - the traumatic images are confronted and changed to less threatening images or new positive images are developed to replace the traumatic ones Rescripting can generate new perspectives, new emotions, previously unrecognized needs, and new realities. Not all studies support the effectiveness of exposure therapy - some indicate that fear responses diminish gradually over time - in which case exposure may be re-traumatizing 4) Stress Inoculation Therapy Form of CBT Involves an education phase - information about trauma and trauma response Rehearsal phase - learning and practicing behavioural and coping strategies Implementation phase - applying learned strategies in life and monitoring progress Combined with exposure therapy this approach has proven effective in reducing trauma symptoms, although studies are limited in number 5) Narrative Focused Therapy Narrative therapy involves a component of exposure with cognitive restructuring. In therapy individuals are asked to reconceptualize and retell their story with a different focus, different possible reactions, perspectives or contexts, or how they wish they and their lives were in reality Expanding narratives to include more detail and complexity is encouraged. By developing these different narratives individuals come to realize that reality is a matter of personal perspective and that they have the capacity to construct alternative views of reality, some of which will help them achieve more desirable outcomes 7) Emotion Focused Therapy Therapy is a process of first - emotional awareness and acceptance and second - emotional transformation. Clients are guided through a description and labelling of their emotions

7 Increased emotional awareness has been associated with developing a more positive mood and decreasing negative ruminations on a negative event Emotion transformation involves identifying if the primary emotion is adaptive or maladaptive, with adaptive emotions being used to guide behaviour and maladaptive emotions being targeted for change. Change of maladaptive emotions consist of modifying emotional schemas. This schematic change can include an increased focus on positive emotions. Positive emotions are related to resilience in terms of more flexible, creative thinking and counteracting the effects of negative emotions 8) EMDR Often used with trauma survivors Person talks about their trauma while moving their eyes rhythmically from left to right Believed this will reset or activate connections between brain structures impaired by the trauma It is more effective at reducing trauma symptoms than relaxation training and stress management alone, but some have suggested that the effectiveness lies with the exposure component of talking about the trauma 9) MBSR Mindfulness is a form of meditation that asks individuals to be fully in the present and to attend to current sensations without imposing interpretation or judgement Physical sensations, internal states and action/environment interactions become the focal point and therefore individuals become aware of multiple sensory experiences and the contexts in which they occur Mindfulness uses a variety of techniques or exercises including meditation, yoga, deep breathing, listening to music, and self monitoring of thoughts. By maintaining awareness of present sensations individuals not only slow down their systemic arousal, but they break past patterns of perceiving the world and begin to experience their world differently. It diverges thoughts from the automatic, habitual perceptions to develop new awareness. The following changes can result from mindfulness:

8 Increased sensitivity to one's current environment Increased openness to new information Increased capacity to formulate new ways of categorizing or structuring perceptions Increased capacity to consider multiple dimension and perspectives when problem solving Becoming unstuck in terms of thought patterns and ending ruminations Other forms of meditation such as focused attention where the individual focuses on one stimuli and filters out other distractors have been associated with increases in cortical connections and a thick cortex Eventually they use less mental effort to focus attention and filter distraction - helps when processing new information (in CBT) These individuals have better attention, alertness and better short term memory Evidence and Recommendations Given that symptoms associated with trauma and PTSD vary considerably across individuals and time, it has been suggested that different approaches may be necessary Therapeutic relationship is a significant predictor of therapeutic success Whatever approach is used there is a need for more evaluative research on all approaches taken to further guide their application with individuals experiencing trauma.

HE 250 PERSONAL HEALTH. Stress

HE 250 PERSONAL HEALTH. Stress HE 250 PERSONAL HEALTH Stress Stress Stress General state of the body, mind, and emotions when an environmental stressor has triggered the stress response Stressor Events or agents in the environment that