Category: hypothalamus

The Biological Effects of Anxiety on the Body

Stress and anxiety can wreak havoc upon your body. It can lead to problems with childhood physical development, and affect the immune, endocrine, gastrointestinal, and cardiovascular systems. It can exacerbate diabetes. Stress affects the mind as well, a tragic example being PTSD, where an individual might relive a traumatic event over and over. 

Stress can be either good or bad event – such as marriage or a divorce. Low levels of stress can actually be a good thing – for instance, a small amount of stress might help you prepare for an upcoming exam better than you otherwise would have. But sometimes stress becomes overwhelming, and biological systems in your body that would usually only slightly increase during “good stress,” go into overdrive – potentially on a long-term basis. 

In order to understand why long-term stress can be bad, we need to understand what immediate effect stress has on our bodies. Under stress, the hypothalamus-pituitary-adrenal system (HPA axis) is activated. The hypothalamus releases corticotrophin-releasing-hormone (CRH). CRH stimulates the pituitary gland. The pituitary then secretes adrenocorticotrophic hormone (ACTH). The Adrenal cortex then produces the stress hormone cortisol in humans. 

Anatomy of hypothalamus-pituitary-adrenal system
Top left, the pituitary gland is red
Top right, the hypothalamus and pituitary glands are connected
Bottom left, the adrenal glands are bright red
Bottom right, the adrenal glands are the yellow cones on the kidneys

Cortisol activates the fight-or-flight response. The sympathetic nervous system shuts down anything that your body doesn’t need during a traumatic event where you might need to fight or run away from a threat. That means your stomach stops digesting, you stop producing semen / ovulating, your immune system – which requires a huge amount of energy – slows way down. Tissue repair – also another drain on energy – halts.  Activation of the sympathetic nervous system leads to release of the adrenaline (epinephrine) and noradrenaline (norepinephrine). These hormones circulate through the body and increase rate of the heart and of glucose metabolism – that gets the oxygen and energy flowing so you can use your limbs for fight or flight. 

Cortisol is the hormone that prepares the body for fight-or-flight; thus, it is a good hormone to have around in an immediate danger. However, if stress continues, and cortisol is not turned off, the long term effects of suppression of vital bodily functions is quite detrimental to the body. Usually, after immediate stress, the cortisol has a feedback inhibition mechanism, in which it signals to slow its own production. However, if the stress continues for too long, cortisol’s feedback inhibition loop can be deactivated; thus allowing the adrenal cortex to continue pumping out cortisol and keeping the physiological effects of the sympathetic nervous system still active. 

Since the immune system is inhibited by the sympathetic nervous system, individuals experiencing long-term stress are susceptible to infection by viruses and bacteria. 


The best known physical side effect of stress is cardiovascular problems. As mentioned earlier in this post, the sympathetic nervous system increases heart-rate so that blood pumps more quickly throughout the body. Not only can this increase blood pressure directly, but it can also lead to damage of the blood vessel walls. The high blood pressure leads to tiny tears in the blood vessel walls. These tears are susceptible to accumulating circulating “junk” such as particles of fat and cholesterol. This accumulation – pictured n yellow above – can decrease blood flow through the vessel, or completely block flow as seen above. When the heart doesn’t get enough oxygen, then a heart attack may occur. Another problem with decreased blood flow is that if the brain doesn’t get enough oxygen, this can cause a stroke. 

As you can see, stress can have a huge impact on your health. Doesn’t that stress you out?


This is a series of posts summarizing what I’m learning in my Abnormal Psychology course. Much of the information provided comes from reading my James N. Butcher’s textbook Abnormal Psychology. To read the other posts, follow these links: 

The Definition of Abnormal
A History of Abnormal Psychology
Abnormal Psychology in Contemporary Society
Contemporary Viewpoints on Treating Mental Illness – Biology
Contemporary Viewpoints on Treating Mental Illness – Psychology
Frontline: New Asylums
Brave New Films: This is Crazy
Clinical Mental Health Diagnosis: Biological Assessment
Clinical Mental Health Diagnosis: Psychological Assessment
Does the DSM Encourage Overmedication?
Post Traumatic Stress Syndrome – The Basics
Panic Disorder
Obsessive Compulsive Disorder
Hoarding and Body Dysmorphic Disorders
Depression – an Overview
Personality Disorders – Clusters and Dimensions
Personality Disorders – Cluster A
Personality Disorders – Cluster B
Personality Disorders – Cluster C
Biological Effects of Stress on Your Body
Somatic Symptom and Related Disorders
Dissociative Disorders
Borderline Personality Disorder
Dialectical Behavioral Therapy
Paraphilic Disorders
Gender Dysphoria – Homosexuality and Transgender
Anxiety Disorders
Bipolar Disorder – The Basics
Suicide – An Overview

References:

Butcher, James N. Hooley, Jill M. Mineka, Susan. (2014) Chapter 5: Stress and Physical and Mental Health. Abnormal Psychology, sixteenth edition (pp. 129-161). Pearson Education Inc.

Panic Disorder

Fear is an emotion that elicits the “fight-or-flight” response of the autonomic nervous system. It is an immediate (uncontrollable) response to a direct danger – such as a rattlesnake, a gun pointed at your head, or a fast car driving right at you. Fear is generally a helpful response that allows you to protect or remove yourself from the imminent peril. 

Sometimes the fear response can occur in the absence of any obvious stimulus – this can lead to a panic attack. Panic attacks are terrifying physiological and psychological events in which your autonomic nervous system ramps you up for fight-or-flight. Often, the person becomes terrified that they are dying – usually of a heart attack. Like intense fear, the heart starts pounding, adrenaline flows, breathing races. Sometimes the victim will run from the room – perhaps to a hospital or perhaps with no direction at all – to escape the unseen threat. 

A person who experiences frequent panic attacks can be diagnosed with panic disorder. A person with panic disorder is terrified of having another panic attack – and even that fear can elicit another attack. Such a disorder can be crippling. I have a friend with panic disorder that struggled in college because she’d had a panic attack during a particular class, and she was intensely afraid to go back to that class, fearing that she might have another attack. According to the DSM-5, in order to have panic disorder, a person must have 4 of 13 symptoms including: pounding heart, sweating, trembling, shortness of breath, choking, chest pain, nausea, dizziness, chills or heat, numbness or tingling, feelings of unreality, fear of “going crazy,” or fear of dying. 

Panic attacks usually last 20-30 minutes with a peak for about 10 minutes, which is good because any longer than that could pose an immediate danger to the person’s metabolism (in case of diabetes) or cardiovascular system (heart attack). 

The fear response in a panic attack originates in the amygdala, which is thought to be the central component of the “fear network.” According to the prevailing theory, panic attacks occur when the fear network is activated. Panic disorder develops in people who have a non-adaptive fear network which is overly-sensitive. Although the physiological response to a panic attack originates in the amygdala, there are also cognitive components to panic disorder (e.g. fear of another panic attack in particular situations). The hippocampus, which is involved in learning and emotional responses, is likely involved in this aspect of panic disorder. The cognitive factors in panic disorder (e.g. fears of dying or going insane) are likely controlled by higher cortical centers of the brain.

There are a couple of theories about the development of panic disorder. In the comprehensive learning theory of panic disorder, a person undergoes classical conditioning – such as Ivan Pavlov discovered when his dogs began to salivate reflexively to the sound of a metronome that was always ticking when the dogs ate. In a process called interoceptive conditioning, the person begins to unconsciously associate physiological arousal (e.g. pounding heart, head rush, increased breathing rate) with panic. Thus, when a person is physiologically aroused, such as while running, she will suddenly experience a panic attack. Panic attacks can also be induced by happy events. For instance, when something exciting happens, such as a marriage proposal, the happy person can suddenly rush into panic. 

Another theory of panic disorder is the cognitive theory. In this case, the person consciously associates physiological arousal with impending doom. When his heart is pounding, he thinks he could be having a heart attack. When his breathing becomes labored, this could be lung cancer. Such thinking is called “catastrophizing.” 

Panic provocation studies support the cognitive theory of panic disorder. In such a study, a subject is given a stimulant that increases heart rate or other physiological symptoms of arousal. One test group is told in advance that the stimulus will increase heart rate, and that it is completely harmless. The other test group will not receive any explanation. It turns out that people who are forewarned of the physiological arousal are less likely to experience a panic attack. This is not in line with the comprehensive learning theory, in which the panic is induced reflexively, and cognition has nothing to do with the attack.

In all likelihood, both theories play some part in the origin of panic attacks. 

Many people with panic disorder are prescribed benzodiazapines such as Xanax or Klonopin. These medications are very useful for anxiety relief, but they can be addictive. Upon cessation of the medication, a patient can undergo uncomfortable side effects such as nervousness, sleep disturbance, dizziness, and panic attacks. For those of you who wonder why we are so dependent upon medications for treatment of anxiety, try undergoing a three hour anxiety attack like the one described in My Bipolar Mixed State. You will soon understand that immediate relief is necessary.

Because of the negative side effects of medication, it is good to treat panic disorder with psychological therapy, such as cognitive-behavioral therapy, as described in Contemporary viewpoints on treating mental illness – psychology. In such treatment, a patient can be exposed to internal stimuli of physiological arousal; for instance, running in place, spinning in a chair, or hyperventilating. The patient must continue this activity until he dissociates the physiological symptoms with panic. Such deconditioning therapy can be combined with education about the nature and causes of panic disorder. The patient can be taught to meditate or control their breathing. Patients are also taught about the cognitive errors that they might be making (i.e. my heart is pounding, I must be having a heart attack). 

This is a series of posts summarizing what I’m learning in my Abnormal Psychology course. Much of the information provided comes from reading my James N. Butcher’s textbook Abnormal Psychology. To read the other posts, follow these links: 

The Definition of Abnormal
A History of Abnormal Psychology
Abnormal Psychology in Contemporary Society
Contemporary Viewpoints on Treating Mental Illness – Biology
Contemporary Viewpoints on Treating Mental Illness – Psychology
Frontline: New Asylums
Brave New Films: This is Crazy
Clinical Mental Health Diagnosis: Biological Assessment
Clinical Mental Health Diagnosis: Psychological Assessment
Does the DSM Encourage Overmedication?
Post Traumatic Stress Syndrome – The Basics
Panic Disorder
Obsessive Compulsive Disorder
Hoarding and Body Dysmorphic Disorders
Depression – an Overview
Personality Disorders – Clusters and Dimensions
Personality Disorders – Cluster A
Personality Disorders – Cluster B
Personality Disorders – Cluster C
Biological Effects of Stress on Your Body
Somatic Symptom and Related Disorders
Dissociative Disorders
Borderline Personality Disorder
Dialectical Behavioral Therapy
Paraphilic Disorders
Gender Dysphoria – Homosexuality and Transgender
Anxiety Disorders
Bipolar Disorder – The Basics
Suicide – An Overview

References:

Butcher, James N. Hooley, Jill M. Mineka, Susan. (2014) Chapter 6: Panic, Anxiety, Obsessions, and their Disorders. Abnormal Psychology, sixteenth edition (pp. 163-210). Pearson Education Inc.