Lecture 6: Chapter 7 – The Autonomic Nervous System and Hormones Flashcards
The autonomic nervous system is a component of the _____ _____ _____ that regulates ____ ____ ______?
The autonomic nervous system is a component of the peripheral nervous system that regulates involuntary physiological processes
The autonomic nervous system connects to organs such as the?
The heart, lungs, stomach, intestines, genitals, and smooth muscle around arteries
The autonomic nervous system consists of two chains of neurons alongside the spinal cord:
- Sympathetic system: “fight or flight” system
- Walter Cannon (1915) determined that the sympathetic nervous system prepares the body for vigorous/stressful activity - Parasympathetic system: “rest and digest” system
- Activates to relax and repair body after periods of stress
List the 6 short-term impacts from the SNS to engage in vigorous activity
- Increases blood flow to brain and muscles via vasodilation of arteries
- Relaxes and expands bronchioles (sacs in lungs) to increase oxygen intake
- Accelerates heartbeat to improve transfer of oxygen to tissues
- Dilates pupils in order for the retina to take in more light
- Also indicates sexual interest
- Increases sweating to cool down body from increased heat
- Piloerection: making the body’s hairs stand up on end
- Makes animal look larger when frightened,
evolutionary relic in humans
- Makes animal look larger when frightened,
List the 3 long-term impacts from the SNS to engage in vigorous activity
- Secretion of adrenaline, noradrenaline, and cortisol to engage body’s stress response
- Stimulates glucose production and release from liver to supply energy
- Stimulates overall cellular metabolism and breakdown of fats in body
List the 5 mechanisms of the SNS to decrease resting/relaxing behaviour
- Constricts blood flow to hands, feet, and skin via vasoconstriction of arteries
2 Inhibits peristalsis (intestine pulsing) and secretion via vasoconstriction of arteries - Inhibits salivation, leading to dry-mouth feeling
- Inhibits bladder contraction, preventing bladder emptying
- Stimulates orgasm (climaxes/ends sexual activity)
Sympathetic nerves travel ____ each other for long distances along the spinal cord, and synapses connecting to different organs are typically ____ ____
Sympathetic nerves travel alongside each other for long distances along the spinal cord, and synapses connecting to different organs are typically clustered together
Initially, researchers believed that sympathetic branch acted in “____” with each other, resulting in an ______ _____
Researchers believed that sympathetic branch acted in “sympathy” with each other, resulting in an all-or-none response
It is now understood that activation of the sympathetic branch is more _____ with different combinations of _______ and ______ _____
Now understood activation is more differentiated with different combinations of neurotransmitters and receptor subtypes
In contrast to sympathetic nerves, parasympathetic nerves ___ __ and head for different organs closer to the spinal cord. Thus?
In contrast to sympathetic nerves, parasympathetic nerves split off and head for different organs closer to the spinal cord. Thus, stimuli that activate one part of system may or may not activate other parts
List the 9 functions of the parasympathetic nervous system (rest and digest)
- Constricts pupils to conserve energy
- Stimulates flow of saliva to aid in digestion
- In cats and dogs, reflects increased parasympathetic stimulation associated with contentment - Constricts and shrinks bronchioles
- Slows heartbeat
- Stimulates peristalsis and secretion of digestive chemicals (e.g. bile) in GI tract
- Insulin secreted to facilitate the storage of energy in fatty tissues and in the liver
- Contracts bladder, allows bladder emptying
- Does not affect blood vessels directly, but less sympathetic activity will send more blood to digestive system, less to muscles/brain
- Big meals make one feel lethargic when exercising, and sleepy (less blood to brain) - Promotes body conditions favourable for sexual activity
- Increases blood vessel dilatation in genitals of males and females, facilitating sexual arousal
Explain the 1st role of the parasympathetic nervous system in emotion
A certain degree of calming is valuable for social relationships and for some positive emotions (Porges, 1997)
Explain the 2nd role of the parasympathetic nervous system in emotion
People with higher resting parasympathetic activation:
1. Tend to be better than average at regulating their emotions (Butler, Wilhelm & Gross, 2006)
2. Report more positive affect in their daily lives (Bhattacharyya et al., 2008)
Explain the 3rd role of the parasympathetic nervous system in emotion
Heart rate predicts amount of compassion people feel and show when someone else is suffering (Stellar, Cohen, Oveis & Keltner, 2015)
1. Moderately slowing your heart rate helps you focus on others and stop worrying about your own problems
2. Too much calming causes people to stop worrying about others as well
How do the sympathetic and parasympathetic systems work together?
Both work in concert to regulate bodily activity (similar to pedal and brake in a car)
Describe how the sympathetic and parasympathetic systems work together in the rabbit example
- After hearing a sudden noise, rabbit’s sympathetic NS will dilate pupils, and slightly increases sweating, and parasympathetic NS will decrease heart rate
- Helps to focus attention on outside environment
Describe how the sympathetic and parasympathetic systems work together in the human example
Humans read a list of objects and evaluated their usefulness in life-or-death situations (thinking of threats, but not yet doing anything about it)
Finding: increased attention being paid to words on the list results in increased probability of remembering words on list
Describe how the sympathetic and parasympathetic systems work together with respect to the nausea example
During nausea, sympathetic NS decreases stomach contractions and induces gagging, while parasympathetic NS stimulates intestines and salivary glands, while slowing heart rate
Describe the methods of Löw, Lang, Smith & Bradley (2008) study on how the sympathetic and parasympathetic systems work together
- Had participants play video game where they have an opportunity to win some money, and sometimes face the threat of losing it
- As gun approaches you and gets larger, you have an increased chance to lose money, unless you react quickly enough when signal appears
Describe the two findings of Löw, Lang, Smith & Bradley (2008) study on how the sympathetic and parasympathetic systems work together
- When gun is small and distant, heart rate decreases (PSN activated to increase attention)
- When gun grows larger, heart rate increases for vigorous response (SNS activated)
Define the endocrine system
Hormones in the body and the glands that produce them
Define Hormones
Chemicals produced and released by glands in one part of your body and carried by the bloodstream to cells of other areas
Insulin (hormone) is produced and released by the _____ to increase ___ ____ __ _____
Insulin is produced and released by the pancreas to increase glucose uptake in cells
Growth hormone is produced in the _____ ____ to promote ___ _______
Growth hormone is produced in the pituitary gland to promote cell reproduction