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Stress on the Brain: Teens and Young Adults, Types of Stress, Coping, and Delusions
The effects of stress on cognitive function are diverse, and dependent on variables such as: the perceived control, the predictability, and the severity of the stress. During adolescence the brain undergoes a massive transformation, that will heavily effect how a person responds to stressors. Chronic mild predicable stress increases neurogenesis and improves memory. High uncontrollable stress leads to learned helplessness and depression. Coping mechanisms can be used to control or cancel the negative effects and increase the positive. Coping mechanisms like exercise decrease depression and improve visuospatal memory. Extreme stress can cause delusional memories and PTSD. The effects of stress on adults are dependant on multiple variables, it can improve cognitive function or destroy it.
map of the brain
Adolescent Mental Development
A distinct behavior change evident in male rats, an increase in "self grooming" that stimulates growth of the Prostate and Seminal Vesicles, when they enter puberty. Such behaviors are accompanied with physical development and are immediately apparent. Adolescent neurological (brain nerves) development is not as visible.
The adult psyche is conditioned in adolescence by the types of chronic stress it encounters. As prepubescent children develop into adults, memory patterns become more internally generated than externally generated, when compared to children. This means that as children mature into adults, our memory becomes more orientated on what we felt and thought at the time, instead of what physically happened to us. Chronic stressors in adolescence permanently alter learning and memory functions as we progress into adulthood.
The effects of chronic stress in adulthood are not long lasting and the changes in neural structure reverse with time; but not in adolescence, when the basic structures are just beginning to develop. There is a large increase in both white matter, the connections between the neurons in their brains is developing rapidly. Adolescents start to have increased control over their emotional and cognitive processes. The increase in the volume of the Amygdala and Hippocampus is largely due to neurogenesis (growth of brain nervous tissue). Catecholaminergic systems important to attention arousal, goal-directed behavior, and stress reaction are remodeled. (McCormic pg. 6)
Biological transitions are a time of increased vulnerability, and change re-activity to the stress systems; especially in the HPA (Hypothalmic-Pituitary-Adrenal) areas. The negative feedback mechanism is immature in the preadolescent HPA axis (the neurons or nerves that connect them). This effects the novel stress reaction. Novel stress occurs when we encounter anything unfamiliar. The novel stress reaction is the similar to an adults but in adolescents rises in cortisone levels last longer, because the HPA is immature.
Preteens and teens are more sensitive to minute stressors, because they have a lower floor for response than adults. They experience more minute stressors and can have equally minute responses.
Repeated social defeat sensitizes corticosterone response in adolescents but not in adults. corticosterone is a negative feed back hormone produce in the brain. This pattern can be observed in any middle school. They begin to form clicks and dread the idea that they are precieved as different. Being different increases the chance of social defeat. The extent of habituation of stress response depends on the stressor, with lower habituation to social instability at this time.
Maturation of the limbic structures that regulate HPA begins to happen early in adolescence. The limbic system is cental to emotion processing. All vertebrates have one, but it is more pronounced in highly intelligent animals. This is the reason that they have all those utopian ideas, that they profess are distinctly their own.
These ideas are caused by the formation of new neural pathways. They are beginning to link together their motivations and emotions. This is new to them and are not fully mature. Dopaminergic projections from the ventral tegmental area to the nucleus accumbens is an important pathway for motivations by facilitating emotional processing.
Risk taking behavior emerges in adolescence as the prefrontal cortical regions develop. In itself an increase in risk taking is a good thing. This will allow them to grow and learn outside of their comfort zone. They will stay away longer, make a more diverse assortment of friends, learn how to use their newly developing judgment skills, and learn how to interact with the world outside of home and school. They are just starting to develop independent judgment and taking risks is how they will learn to use it. Judgment is an extremely complex task, requiring further brain development. This is the brains main area of development till about the age of 25. The Prefrontal Cortex needs practice and exercise to develop properly. Through risk taking behavior it will develop connections to every other part of the brain, not just with in itself. Because the judgment process is far from fully developed, they need guidance on how to evaluate risks. The lessons on how to evaluate and take risks will follow them for the rest of their lives. If left to their own devices they are set up for disaster.
There is a decrease in longterm and latency period spatial learning when compared with children and adults. they will learn quickly from the immediate concequences of their actions. Unlike adults and children, the delayed concequences of doing something, getting caught, then punished; are more difficult for them to learn from. Adolescent brains are tuning themselves to the here and now. This is a stage when the present has the most bearing over actions.
In adolescence our growth and metabolism are protected from stress responses but psychologically we are at an increased risk. Bullying has serious consequences at this time. The names and insults can be more damaging physical assault. High stress impairs spatial memory retrevial without impairing spatial learning, by disrupting the Hypothalmus and selectively destroying dendrites and eventually neurons in this area while suppressing neurogenesis. Exposure to elevated chronic stress inhibits medial prefrontal cortical dependant tasks, such as extinction of conditioned fear and shifting attention along with hindering some spatial performance.
Chronic elevation of glucocoroids causes the dendrites in the Hippocampus, Medial Prefrontal Cortex and Basolateral Amygdala to retract. This is also accompanied by a decrease in neurogenesis in the Dentate Gyrus. (McCormic pg. 5) The partial destruction and stunted growth of these vital parts of the brain permanently impairs learning, judgment, and emotional processing.
Environmental experiences while in adolescence can influence spatial cognition when they become adults. When subjected to high stress, hippocampal proteins associated with learning and memory are significantly decreased. The extinction of conditioning is markedly reduced. (McCormic pg. 7)
Neural activation is increased by exercise. (McCormic pg 4) the more activity the neurons are, the more they will grow. This makes physical activity essential for healthy mental development. They will gain more from their experiences and develop stronger judgment if they are physically active.
This is a period when an individuals psyche is very vulnerable to stress. high stress environments have long lasting impacts on many cognitive abilities including memory. This is when the brain begins to associate motivations with emotions. This is when independent judgment starts to develop entirely on its own. This is when they learn, why to fear and how much to fear something. They need guidance and exercise to develop properly.
which is worse: something you can't control, or something you can't see coming
Types of stress can be classified as either dysphoric or euphoric. They are both stress and act on the body identically, but mentally they are very different. Euphoric stress is good stress, like the anticipation of a child Christmas morning. Dysphoric stress is bad stress, like not being able to make credit card payments. When people talk about stress they are almost exclusively talking about dysphoric stress. for the rest of this article the term stress is referring to dysphoric stress.
Mild Chronic Stress
All stress is not bad. The chronic mild predicable stress we encounter every day is beneficial to learning and memory, providing stimulus for growth. CMPS (Chronic Mild Predictable Stress) stimulates neurogenesis particularly in the Hypocampus. Things that also increase neurogenesis are anti-depressants, enriched environments, and exercise.
Now, I know what you've probably heard about rats that have the misfortune of ending up in stress experiments. They can have some hope of ending up in one that only subjects them to 5 minutes of restraint per day for 28 days, always at the same time, and periodically tested as their cognitive abilities improve for about 2 months. It takes about 6 weeks for new neurons to be Incorporated in spatial memory systems. After their 2 months of testing for prolonged improvements, they are euthanized and have their brains dissected. The rodents showed a decrease in depressive and anxiety behavior. Neurogenesis and neuropasticity went way up. There was 51% post restraint day 1 drop in depressive behavior compared to handled control, and the effects lasted for long periods.(Parihar pg. 3) They were 3 times more likely to indulge in open arms with 4.5 fold increase in time spent in open arms, showing a huge reduction in anxiety. The behavior not only persisted but continued to climb to a 6.3 fold increase at the end of 2 months. Upon dissection they had 1.5 fold increase in density and size of neurogenesis clusters in the Hypothalmus. No signs of neurodegeneration or inflammation were found. They showed no change in fate-choice of new neurons when compared to control. 1.6 fold increase in Hippocampus neurogenesis. The cells were of higher quality. 1.8 fold increase in dendric length per cell accompanied with 1.9 fold increase in dendric nodes per cell. These rats did no better than control in learning tasks but showed a remarkable improvement in memory. Spatial memory and novel object recognition were particularly effected. In this study they gave a N value of 12: 6 restraint, 6 handled for control.(Parihar) I think this is because of the "niceness" with which this experiment was conducted.
CMPS is something we all live with and it is beneficial. Without stress we cannot learn or remember what we learn.
Unpredictable chronic stress, sever stress, and depression inhibit neurogenesis. Unpredictable stress is when you can't see it coming. It shows up out of the blue. Depending on your personality type this may be the worst kind of stress. This is when you get waylaid from right field. what negative experience is going to happen next is any ones guess. While some unpredictable stress is normal and healthy, to much can have sever consequences. Unpredictable stress is often the result of an uncertain environment. If you find yourself in an environment that is causing your mental health to deteriate, immediately seek professional help. Sometimes it takes an outsider to help identify and cope with extremely fluctuating elements in an environment.
Sustained high levels of uncontrollable stress can cause learned helplessness in lab rats. An easy way to teach a lab rat helplessness quickly is to put them in a cage with an electrified floor with no way for the rat to turn it off. To speed up the process make the floor electrified at random times so it is not predictable to the rat. Also, give the rat nothing that facilitates coping, this means nothing to chew on, no exercise wheel, no way to bury anything, and no social contact. Learned helplessness has all the observable effects of chronic depression. The rat will be slow to learn that it can move to the other side of the cage when signaled by a light. It will be slow to learn it can turn it off as compared to control rats. After helplessness has been learned, it will just lay there and get electrified.
These learning difficulties apply to more than just getting zapped but to all stressors it encounters. It is estimated that between 5% to 20% of people will have incompacitating depression at least once in their lives. (Sapolsky pg. 271) Most people will recover from it, even from the second and the third time, but the fourth has a tendency of being more permanent even in lab rats. Depression is not having the blues for a few days or weeks it is persistent for at least 2 weeks or more, even years.
Depressions defining feature is the inability to feel pleasure, called anhedonia or dysphoria. There are many types of depression, but generally there is a large decrease in positive emotions and a large increase in negative emotions. Suffers often have delusional negative thoughts. Neurons degenerate when increased levels of glucocorticoids are sustained. This degeneration is particularly evident in areas of the brain central to memory formation and retrieval: the Hippocampus, Hypothalmus, Prefrontal Cortex, and Amygdala.
There is a vast array of coping mechanisms. Social support, turning it into a positive, putting the stress into context, meditation, prayer, distractive pursuit, and exercise are just a few of them.
Just having some one to talk to is the strongest coping mechanism known. The absence of social support is the strongest mental stressor human beings can experience. Support groups come in a vast variety of forms. Common support groups can be family, friends, religious organizations, and professional help. People who find help dealing with stressors are more likely to resolve issues and cope. Healthy social support groups help people overcome obstacles. It is way easier then trying do to do it all by yourself. The actions of an individual are limited in effecting an environment. A healthy supportive group can help a person evaluate how much control they have over a stressor, and how to adapt. Not everything can be changed, sometimes it can only be accepted.
Turning a bad into good is very effective at managing stress. Sometimes it's as simple as rephrasing: "I have to study" versus "I get to learn", is a drastic change in out look. how you look at stress changes how it effects you. Another effective method is to see how you can help others. you can also see how your problems are for a better good. finding ways to change bad stress into good stress is very effective. changing your perception of stressors can help alleviate the negative effects of dysphoric stressors by turning them into euphoric stressors.
How to adapt to stress is a tricky thing. The cause and extent of stress must be put into context. How to accept the fact that you will be paralyzed for the rest of your long life, is much different then how to accept the fact that people with out handicaps some times park in handicapped spots. Successfully adapting to both follow similar patterns. In both cases you must accept that you have a limited capability of changing it. Finding only one reason why it's a positive creates a weak mental adaptation; the more you can find, the better. You must also realize how much effect the stressor has in your life. If it is something you can control, will devoting your time and resources to change it, be worth it? Is it worth a bad day, hour, or minute? stressors need to be put into contex so they can be evaluated for successful adaptation. How much control do you have over it? How predictable is it? How much of an impact does it have on you? How long will the effect last? why does this stressor happen? there are many more questions that need answers to evaluate stressors, but these are the major ones. By putting stressors into contex you are more likely to deal with them better.
Often stressors are internally generated. There is a proverb "There are two wolves fighting inside of me. One is hate and the other love.' said a Wise-man. A young person asked 'Which one will win?' The Wise-man said 'The one that I feed". We can control allot of stress by how we choose to think. If you choose to think negatively, you will develop allot of negative stress that will harm your well being. If you choose to think positive, you will develop a lot of positive stress that will help you to learn and grow.
There are many forms of meditation. Meditation is a mental exercise were you intentionally change your perspective with the intent of finding a solution. In meditation you typically look with in your self, with out the distractions of what is going on around you. Their are many types of mediation, all of them differentiating on the exact approach. Zen meditation is known to be highly effective. During Zen meditation you attempt to focus on nothing. First you begin by finding a quiet place that offers little distraction. Get into a comfortable position with good posture. Ignore your senses, do not concern your self with what is going on around you. If a dog barks, accept that a dog is barking and ignore it. You will start to develop day dreams, ignore those to. Accept that you are day dreaming when it, and release yourself from it. It can be described as emptying your mind, but it will develop into a mindfulness. This will be something new that your mind is not accustomed to. It will need to be trained. Day dreams are typically of the past and the future, during this mental exercise you want to become aware of the exact moment. The exact moment is not a second from now or a second ago. The effects of Zen mediation have been conclusively shown to reduce stress, increase attention span, develop awareness, and improve creativity. Zen is just one form of mediation their are many others.
Prayer is effective. During prayer you look to a higher power for help. Prayer changes your perspective much like meditation. You look outside of earthly things for help. Some people consider them to be the same thing, but its an opposite change of perspective. the effects of prayer and mediation, on how people cope with stress are very similar.
Finding something to take your mind off it for a bit. This can be helpful as long as the stressor isn't ignored completely. Sometimes things can become overwhelming, filling your mind with all day. A hobby is giving yourself a break from the constant assault of stress. A hobby is a break, this means you have to be constructively dealing with your stress the majority of the time.
simple yet effective
Stress and Exercise
We have many ways of coping with stress one of them is exercise. Exercise increases visuospatal memory. In the general population of young adults, exercise is not linked to improvements in concentration or verbal memory. It will decrease clinical depression however along with anger and stress. as people get older, mental abilities like concentration and verbal memory tend to decline. Exercise then begins to have clinically significant impacts on mental acuity. Exercise can help put excessive stress hormones to work neutralizing their negative effect.
In clinical samples, older subjects typically start off with markedly higher ceiling when compared to young adults. As people get older, most of us lose neural plasticity. After our mid twenties, our brains begin to specialize in certain tasks. This natural part of aging allows there to be an increase in cognitive function from exercise. The older an adult gets the larger the positive gains from exercise because of this ceiling effect.
We all can get an increase in speed tasks (reaction time), visuospatal and visuoattention, effortfull processing, and executive control benefits from regular aerobic exercise. People who exercise regularly have an increase of .5 standard deviations (5 points) in cognitive performance (IQ) over the general population.
The robust protective influence of a regular work out as we age is well documented. Aerobic exercise increases regional blood flow in the brain. It facilitates neuroplasticity. Serotonin and Dopamine secretion show marked change. This is an anti-depressant effect. Increased blood flow and a positive outlook on life slows mental deterioration as we age.
An increase in neurogenesis is accompanied by keeping yourself in shape. A study (n=23) of adults 17 to 29 years old was conducted by Stroth.(Stroth pg. 9) After 6 weeks individuals partaking in 30 min aerobic exercise 3 times weekly showed an increase of 1 standard deviation in visuospatal memory tasks assessed by the Visual and Verbal Memory Test (VVM; Shellig and Schachtele, 2001), with no change in verbal memory and concentration, assessed by d2 Test of Attention (Brickenkam, 2002).
When we are stressed our brains increase stress hormones. In most animals these hormones are caused by external threats and are metabolized through the fight or flight response. Human stress response is usually internally generated. There is rarely an immediate threat of getting eaten or dieing of starvation. Our power to drive our flight or fight response creates an over-abundance of these stress hormones. By engaging in regular exercise we can "burn off" the excess along with that stubborn belly fat. This will lower your overall stress hormone levels and continue to sustain its reactiveness. Your stress reaction will turn on faster when you need it, then shut off when you don't.
As we get older the ability to respond to stress takes longer to initiate and then won't shut off. An example would be: a 70 year old man goes for a jog, his heart rate will rise slower than it did when he was 20, and when he stops jogging his heart wont stop racing.
Delusions (Delirium) are a common type of false memory encountered by faculty in Intensive Care Units (ICU) in hospitals. Delusional memories increase with critical illness, sedation, chemical withdrawal, and abnormal environments. Delusions often coincide with confusion, disorientation in time and place, decreased cognitive function, and compromised ability for information processing. This is different from Psychiatric morbidity associated with amnesia and memory disorders.
Delirium selectively effects episodic memory (personal events). Sleep deprivation lowers memory consolidation and can produce hallucinations, and these can be exacerbated by physical restraints and isolation.
The limited external stimuli common in hospitals draws attention to internal stimuli causing patients to have poor recall of external events, but vivid recall of dreams, nightmares, and delusions. 26% to 73% (difficulties with accurate reporting: Kiekas) of ICU patients have delusional memories of their experience. The main factors contributing to the amount of delusional memories versus factual memories are length of stay, sedation, infection and/or high fever, whether they had surgery immediately before admittance, if they were on a ventilator, renal failure, and low hemoglobin.
Delusions are persecutory in nature, with vivid recall and lots of details. Patients think they are real at the time and question their factuality much latter. Why ask if something we all just saw, happened? It later when they begin to rationalize their experiences, that they begin to question whether those wild occurances happened.
PTSD is triggered by a serious threat to one's own physical integrity, accompanied by feelings of intense fear and helplessness. Usual symptoms are psychologically re-experiencing the event, avoidance/numbing of emotion, and prolonged hyper arousal. These symptoms will follow the triggering traumatic experience with latency period ranging from 6 weeks to 6 months.(Kiekas pg.6)
The link between delusions and PTSD is that delusions increase with depression and anxiety. Extreme stress leads to PTSD, but PTSD does not corelate to factual versus delusional memories. Increased stress exponentiates depression and anxiety and can cause nightmares which can be a major source of stress.
Recalling the details of delusional memories does not fade with time, the recall of details in factual memories does. When delusions begin they make even more stress, so even unpleasant memories if they are real become protective in this vicious cycle.
The longer delusional memory creation persists the stronger the PTSD created. When the patient gets out of the hospital, the more delusional memories that they created is related to the delay before they return to work. Sleep and family problems often develop with the decrease in mental health. The patient may see a decrease in emotional role and social functioning. Anxiety, depression, and PTSD are very common post ICU experiences it is estimated that 14 to 27 percent of ICU survivor develop PTSD and it may persist for years.
Delusional memories are a stress-related type of false memory, that identify the person having them as being in a group, with increased likely hood of PTSD.
During adolescence our brain is trained on how to learn from stress with prolonged impact of that learning as the brain shapes itself to adapt us to our environment. Mild to moderate stress give us stimulation for learning and growth, facilitating cognitive processes including memory. It is important that we learn constructive ways of dealing with stress and exercise is one of the many ways we can do this. In times of stress we often create false memories. Delusions occur when our tendency for remembering external stimulus is replaced by shifting to much of our attention to internal stimulus. Rats are also capable of leaning helplessness and developing depression making this more than a human phenomenon. Some stress is a good thing to much can be very bad for mental health. Stress can improve cognitive function or destroy it.
Kiekkas, P. P., Theodorakopoulou, G. G., Spyratos, F. F., & Baltopoulos, G. I. (2010). "Psychological Distress and Delusional Memories After Critical Care: a Literature Review". International Nursing Review, 57(3), 288-296. doi:10.1111/j.1466-7657.2010.00809
Parihar, V. K., Hattiangady, B. B., Kuruba, R. R., Shuai, B. B., & Shetty, A. K. (2011). "Predictable Chronic Mild Stress Improves Mood, Hippocampal Neurogenesis and Memory". Molecular Psychiatry, 16(2), 171-183. doi:10.1038/mp.2009.130
Sapolsky, R.M. Why Zebras Don't Get Ulcers: An Updated Guide To Stress, Stress Related Diseases, and Coping. 2nd Rev Ed, April 15, 1998
Stroth, S., Hille, K., Spitzer, M., & Reinhardt, R.(2009). "Aerobic Endurance Exercise Benefits Memory and Affect in Young Adults". Neuropsychological Rehabilitation, 19(2), 223–243