Textbook Notes (367,860)
Canada (161,460)
Shauna Burke (120)
Chapter 3

Chapter 3.docx

4 Pages
Unlock Document

Health Sciences
Health Sciences 1001A/B
Shauna Burke

Chapter 3 Stress: The Constant Challenge What is stress? Stress refers to: 1.) Situations that trigger physical and emotional reactions = stressors 2.) The reactions themselves = stress response Stress = the general physical and emotional state that accompanies the stress response  Not only a physical reaction, also an emotional component Response to Stressors  The primary determinant of health consequences of stress is how the individual responds to the stress  Responses to stressors include: o Physical changes o Emotional and behaviours responses Physical Responses to Stressors Two control systems are responsible for the physical response to stressors: 1.) Nervous system 2.) Endocrine system Nervous System Consists of the Autonomic Nervous System which consists of: 1.) Parasympathetic Division  In control when you are relaxed  Aids in digestion, storing energy, growth promotion 2.) Sympathetic Division  Activated during arousal and emergency situations (pain, anger, fear)  Releases norepinephrine which commands body to mobilize energy resources to respond to crisis and causes arousal (increases attention and alertness) when released in the brain Endocrine System  The system of glands, tissues, and cells that help control body functions by releasing hormones and other chemical messengers into the bloodstream  Helps prepare the body to respond to a stressor Nervous System + Endocrine System Brain detects threat:  Neurochemical message sent to hypothalamus which releases chemicals to pituitary gland which releases adrenocorticotropic hormone (ACTH) into bloodstream  ACTH reaches adrenal glands which release cortisol and other key hormones into the bloodstream Simultaneously:  Sympathetic nerves instruct Adrenal Glands to release the hormone epinephrine which triggers several bodily changes  Examples: acute hearing and vision, increased heart rate, increased perspiration, etc. Fight or Flight reaction (Sir Walter Cannon) **Physical changes vary in intensity but the same physical reactions occur in response to both positive and negative stressors Physical Responses to Stressors Homeostasis  A state in which blood pressure, heart rate, hormone levels, and other vital functions are maintained within a narrow range of normal  Once a stressful situation ends, the parasympathetic division of the ANS initiates adjustments necessary to restore homeostasis Fight-or-Flight Reaction in Modern Life  A survival mechanism that is part of our biological heritage  Not often necessary – many stressors we encounter do not require a physical reaction  Fight-or-flight reaction prepares the body for physical action regardless of whether it is an appropriate response Emotional and Behavioural Response to Stressors Tend-and-Befriend  In addition to fight-or-flight, humans may respond to stress with social and nurturing behaviour  Especially characteristic of females; female response to stress evolved to protect self and offspring  May depend on underlying biological mechanisms (e.g. hormone oxytocin) Stress and Disease Explaining Stress and Disease 1) The General Adaptation Syndrome (GAS)  Developed by Hans Selye (1936)  Stressors can be pleasant = Eustress  Stressors can be unpleasant = Distress  Sequence of physical response is the same for both  Three reaction stages Stage One: Alarm (initial stressor) o Includes fight-or-flight response o Body is prepared to deal with crisis  more susceptible to disease o Symptoms = headaches, indigestion, anxiety, disrupted sleep/eating Stag
More Less

Related notes for Health Sciences 1001A/B

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.