Stress and the Brain

Stress is a normal response to challenges that arise in everyday life. In some situations, stress can be useful, it can increase focus, performance, energy, and alertness, allowing us to perform and think better. Experiencing stress can also help us build our coping skills and learn how to adapt easily. When stress becomes overwhelming or prolonged, it can have a severe impact on the brain and body. Understanding how stress works can empower you to manage its effects and help prevent the negative effects.

What Happens in the Brain During Stress?

When you encounter stress, your brain activates the hypothalamic-pituitary-adrenal (HPA) axis, releasing hormones like adrenaline and cortisol to prepare your body to respond. This is known as the “fight-or-flight” response. While helpful in short bursts, such as responding to danger or meeting a deadline, long term or chronic activation of this system can harm the brain.

For more information on the HPA axis and its role in stress, visit APA's Guide to Stress.

Fight or Flight

The fight-or-flight response is the body’s natural reaction to perceived threats. It prepares you to either confront the challenge (fight) or escape the danger (flight). This response involves a cascade of changes in your brain and body, including:

• Increased Heart Rate and Blood Pressure - To deliver more oxygen to your muscles and brain.
• Rapid Breathing - To supply more oxygen to the bloodstream.
• Release of Adrenaline and Cortisol - These hormones mobilize energy and sharpen focus.
• Heightened Senses - Vision and hearing become more acute to detect threats.

While this response can be lifesaving in short-term situations, chronic activation of the fight-or-flight system due to ongoing stress can lead to:

• Fatigue and muscle tension
• Increased anxiety or hypervigilance
• Cognitive impairments such as difficulty concentrating or remembering tasks

This is especially significant for individuals with neurological conditions, where prolonged stress can amplify symptoms and interfere with daily functioning.

Cortisol: The Brain’s Stress Hormone

Cortisol is a key player in the body’s stress response. In small doses, it:

• Boosts energy by mobilizing blood sugar.
• Enhances focus and alertness.
• Regulates inflammation and immune responses.

Though cortisol in little amounts can be healthy, prolonged exposure to cortisol from chronic stress can disrupt the brain and body. By managing stress effectively, you can keep cortisol levels in check and protect your brain and body.

How Stress Impacts the Brain

When the brain endures stress for a long time many different parts of the brain may be impacted.

Hippocampus

The hippocampus, which oversees the processes involving memory and learning. Chronic stress and high cortisol levels can cause the hippocampus to shrink, which can make it harder to remember and retain information. For example, stress might make it harder to remember where you left your phone, put your keys down, or pay attention during a meeting.

Amygdala

The amygdala, which processes fear and emotions, becomes hyperactive under stress. This can make small frustrations feel overwhelming or increase anxiety about everyday situations.

Prefrontal Cortex

Chronic stress weakens the prefrontal cortex, which governs decision-making and self-control. This may lead to impulsive behavior, poor time management, or difficulty concentrating.

Everyday Impacts of Stress on the Brain

Stress affects how we live, work, and interact daily. Some common signs include:

Cognitive Symptoms

• Forgetfulness
• Mental Fog
• Sleep Problems
• Difficulty Focusing
   

Emotional Symptoms

• Emotional Outbursts
• Anxiety
• Feeling Overwhelmed
• Feelings of Sadness
• Social Withdrawal
• Hypervigilance
   

Physical Symptoms

• Muscle Pain
• Digestive Problems
• Feeling Tired
• Weakened Immune System
• Skin Issues
• Appetite Changes
• Heart Issues
• Hormonal Changes
   

Strategies to Manage Stress

The good news is that our brains are resilient. There are many ways to mitigate stress:

Practice Mindfulness  -  The 4-7-8 breathing technique can help reduce stress. Breathe in for 4 seconds, hold for 7 seconds, and exhale for 8 seconds. This can help reduce stress and anxiety.

Exercise Regularly - Engaging in 30 minutes of exercise daily release endorphins and can help your mood. Walking, yoga, boxing, or anything that makes you move can help with your overall stress levels.

Get Enough Sleep - Having a sleeping routine is extremely important for managing stress. Have a bedtime, keep away from the screen, and create a dark, comfortable sleep environment.

 Keep Social Connections -  Being around friends can help with stress. Try to schedule some social team weekly if possible, or even keep connected via phone.  

Be Creative - Have a creative outlet that you enjoy. This can be playing music, journaling, arts and crafts, woodwork, or dancing.

Seek Professional Help - If you feel like stress has become overwhelming contacting a professional can be beneficial. Anyone who needs help can call the crisis hotline at 988. 
 

Stress is a part of life, but its effects don’t have to be permanent. By understanding how stress and cortisol impact the brain and taking proactive steps to manage them, you can protect your mental health and improve overall well-being. If stress feels overwhelming, remember that support is always available—whether from a trusted friend, a professional, or a resource like this one.