6. GAS model

• GAS - General Adaption Syndrome
• Rats exposed to different stressors but would have the same reaction regardless; physical stress response is non-specific and is identical within all members of a species
• There are 3 distinct phases in the GAS Model; Alarm, Resistance, and Exhaustion
• Alarm Phase - helps to cope with emergency short-term changes in our environment.
• Within the Alarm Phase, there are 2 parts; the Shock and Counter Shock parts
• Shock - when you are first aware of a stressor, and the ability to cope falls below normal
• Counter Shock - Activation of Sympathetic Nervous System, and the release of adrenaline and cortisol
• Resistance Phase - The use of max resources to cope and adapt. Physiological arousal stays above normal and Intense arousal deminishes
• In Resistance, unnecessary processes shut down and cortisol enters the blood stream
• Exhaustion Phase - When a stressor is not dealt with for a long period of time
• Cortisol decreases Immune Responses
• In the Alarm phase, Cortisol and Epinephrine start, and continue on into the Resistance phase in response to long-term stressors
• During the Resistance Phase, heart rate, blood pressure and muscle tension increase, immunity decreases and sugar regulation is abnormal
• Exhaustion is the phase where the body cannot cope with the elevated metabolic rates anymore, resulting in different diseases and function impairments
• GAS Model

  
• Chronic Stress can affect Brain Shape, function and size