The Impact of Stress on the Brain
Not all stress is created equal. Occasional stress can be useful – like when you need to focus on an exam, compete athletically or react quickly to avoid a sudden threat. Consistent stress is poisonous. It wreaks havoc on mood and sleep, zaps energy and can literally change your brain, affecting its size, structure and ability to function normally.
The brain is made up of complex webs, or circuits, of specialized cells called neurons that send electrochemical messages within the brain and throughout the body.
For example, your brain is constantly scanning for threats and rewards. When one is detected, the limbic system (AKA the “feeling and reacting brain”) alerts us by releasing chemical messages. When your brain detects something pleasurable, like hiking in nature or laughing with a friend, the brain releases chemicals that signal the body to relax and feel good: dopamine, oxytocin and serotonin. When it detects a threat, it releases adrenaline and cortisol, signaling our body’s stress (“fight or flight”) response.
Because we’re wired for survival first and foremost, the feeling brain is often the first responder to incoming information, reacting milliseconds before the thinking brain can make sense of it. Another term for this is an “amygdala hijack.” The amygdala, a part of the feeling brain, sends out a threat alert, sparking an immediate emotional response totally out of proportion to the reality of the situation.
When stress becomes chronic or acute
Some of us are more susceptible to chronic stress than others, or go through life events that are particularly stressful, causing our brain’s natural stress response to remain in high alert.
When the brain’s stress response fails to shut off, stress chemicals (cortisol, adrenaline) remain elevated and ‘feel good’ chemicals (serotonin, dopamine) are suppressed, resulting in a wide range of impacts to health, from regulating emotions to sleep, sensory perception and even memory challenges. These changes in the brain can set the stage for mental health problems such as anxiety, depression and psychosis.
Panic attacks are one example of this type of dysfunction, in which we find ourselves having acute responses to stress in less than life-threatening situations, like history class.
Thoughts are powerful. Being aware of them helps.
OK enough with the bad news already. If you’ve been stuck in a stress vortex for a week or most of your life, treatment can help, and there are lots of things you can do to get stress response back in check.
One of them is paying close attention to your own thoughts, which play a big role in your body’s response to stress.
Example: If you’re about to play a championship basketball game and you’re imagining yourself missing the winning shot, your brain is going to flip on the stress response and you’ll have a negative emotional reaction. By shifting your thinking to the positive, envisioning yourself playing your best, you can help your brain avoid the hijack trap, and stay focused on your 3-pointer.
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