General Adaptation Syndrome: some initial thoughts by David Kraft.
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about the role of the endocrine system in stress. I would also like to point out why it is important to differentiate between fear responses and long-term fear. This is also the case for short term stressors and the long term variety.
It appears that fear is controlled by the amygdala. When we are aroused by strong feelings, or when we are alerted, there is a pattern of physiological responses. This is often, as Tina suggested, referred to as a fight or flight response (Canon, 1932). The body is aroused and motivated via the sympathetic nervous system and the endocrine system. At this time our heart rate and blood pressure increase, breathing gets faster and blood is diverted to the muscles ready for action. As Tina said, the sympathetic nervous system actively increases while the parasympathetic nervous system reduces activity. But, the amygdala is accessed very quickly. It by-passes, if you like, other mechanisms that might be used to evaluate the validity of this potential threat. LeDoux (1998) called it the ‘quick and dirty route’. The autonomic reactions and hormonal secretions happen unconsciously. So, in short, our initial reaction to a stimuli works on an emotional plane rather than a cognitive one. We are conditioned to fear from previous experience. This is classical conditioning. We are particularly responsive to auditory stimuli and gustatory stimuli. This is why it is very difficult to threat phobic anxiety using some of the strategies that CBT practitioners use. Techniques such as cognitive restructuring and education will have little effect until you break the pattern of behaviour. Evans and Coman (2003) talk about the fear of the fear, and often it is the anticipation of a series of events that make a phobic reaction so devastating for the individual concerned. So, for psychotherapists, it is particularly helpful to break patterns of behaviour. This can be used in conjunction with systematic desensitization. A biological explanation for this is as follows. If we re-evaluate and change the emotional response to certain situations we send outputs to many brain regions including the lateral hypothalamus and the amygdala. In fact it is the ventromedial prefrontal cortex that does his. It receives information about the environment, it performs a range of behaviours and physiological responses and is involved in inhibiting emotional responses to certain situations. In short, this part of the brain is associated with the control of planned behaviour. As the GAS theory suggests, there are types of stress. GAS theory divides them into three—Alarm Reaction, Resistance and Exhaustion. Most text books of the Biomedical model talk about two: acute chronic stress, which is short-lived, and chronic stress which is ongoing. When stress continues an initial alarm reaction has passed and individuals adapt to high arousal, as the body tries to defend itself (Selye, 1956). Later, we become exhausted and this is when damage is likely to occur. As a result, we become depressed or anxious, and this may have an effect on our autoimmune system. Criticisms to this theory are as follows: 1 It assumes a uniform and non specific physiological response With regard to point 3 above, ones perception of any stress is at the heart of whether it causes stress and anxiety o not. Lazarus and Folkman (1984) suggested that in the primary stages of stress we regard the stimuli as (1) a challenge, (2) a threat or (3) something can cause dame. This is the transactional model. Think of a situation as a challenge can be a useful technique for clinicians. As a therapist and someone interested in the psychoneuroimmunology, I am ken to use systematic desensitization and re-framing in order to reduce learn term stress. |
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David Kraft
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