Autonomic Nervous System and Volitional Movement

Question 1

What role does the autonomic nervous system (ANS) play in voluntary actions?

Answer 1

The ANS is crucial for regulating physiological processes that support voluntary movements and physical activity.

Question 2

What is the relationship between muscles, blood supply, and energy during physical activity?

Answer 2

Muscles require adequate blood supply, oxygen, and energy for contraction, and these processes are interdependent and controlled by the central nervous system (CNS).

Question 3

What are the two main components of the central nervous system (CNS)?

Answer 3

The somatic nervous system (activates muscles for movement) and the autonomic nervous system (regulates physiological functions).

Question 4

How does the ANS contribute to cardiorespiratory regulation?

Answer 4

The ANS ensures blood and oxygen reach exercising muscles and regulates energy metabolism to balance energy intake and expenditure.

Question 5

Why is maintaining physiological processes important during physical activity?

Answer 5

It supports muscle function and maintains vital signs within a safe physiological range, preventing harmful conditions like stroke or heart attack.

Question 6

How does inactivity affect the body according to the lecture?

Answer 6

Inactivity leads to deconditioning, resulting in changes in cardiorespiratory and energy systems, requiring rehabilitation of these systems.

Question 7

What are the three main branches of the autonomic nervous system?

Answer 7

The sympathetic, parasympathetic, and enteric divisions.

Question 8

What are the primary functions of the sympathetic and parasympathetic nervous systems?

Answer 8

The sympathetic nervous system supports “fight or flight” responses, while the parasympathetic nervous system promotes “rest and digest” activities.

Question 9

What is the enteric nervous system and how does it relate to the ANS?

Answer 9

The enteric nervous system independently controls gastrointestinal functions but can be modulated by the sympathetic and parasympathetic systems.

Question 10

How do the sympathetic and parasympathetic systems innervate organs?

Answer 10

Each organ receives input from both systems, allowing for dual control and modulation of physiological responses.

Question 11

Where are the sympathetic and parasympathetic ganglia primarily located?

Answer 11

Sympathetic ganglia are in the thoracolumbar segments of the spinal cord, while parasympathetic ganglia originate from the brain stem and sacral segments.

Question 12

How do the sympathetic and parasympathetic nervous systems affect heart contraction?

Answer 12

The sympathetic nervous system increases heart contraction rate, while the parasympathetic nervous system decreases it.

Question 13

Why is it important to understand how different organs are modulated by the sympathetic and parasympathetic systems?

Answer 13

This understanding aids in comprehending how physiological responses are controlled and can be referenced for clinical applications.

Question 14

What are the two divisions of the autonomic nervous system?

Answer 14

Sympathetic and parasympathetic divisions.

Question 15

How many neurons are involved in the autonomic nervous system circuitry?

Answer 15

Two neurons: pre-ganglionic and post-ganglionic

Question 16

Where are the pre-ganglionic neurons of the sympathetic nervous system located?

Answer 16

In the thoracolumbar segments (T1 to L2 or L3) of the spinal cord.

Question 17

What neurotransmitter is released at the synapse between pre-ganglionic and post-ganglionic neurons?

Answer 17

Acetylcholine.

Question 18

What is the main neurotransmitter for post-ganglionic neurons in the sympathetic system?

Answer 18

Norepinephrine (with some exceptions like sweat glands).

Question 19

What types of receptors are associated with acetylcholine in the autonomic nervous system?

Answer 19

Nicotinic receptors (on post-ganglionic neurons) and muscarinic receptors (on effector organs).

Question 20

What are the neurotransmitters critical for the functioning of the autonomic nervous system?

Answer 20

Norepinephrine, epinephrine, and acetylcholine.

Question 21

Where are the pre-ganglionic neurons of the parasympathetic nervous system located?

Answer 21

In the brain stem and sacral segments (S2 to S4)

Question 22

What is the craniosacral outflow?

Answer 22

The term referring to the parasympathetic nervous system’s origin from cranial and sacral nerves.

Question 23

What is the primary function of the sympathetic nervous system?

Answer 23

To drive the ‘fight or flight’ response.

Question 24

What is the primary function of the parasympathetic nervous system?

Answer 24

To engage in ‘rest and digest’ phenomena.

Question 25

What type of neurons are present in the somatic nervous system?

Answer 25

A single neuron projecting from the spinal cord to the skeletal muscle.

Question 26

What are the paravertebral and prevertebral ganglia?

Answer 26

Locations of post-ganglionic neurons in the sympathetic nervous system.

Question 27

What is the central autonomic network?

Answer 27

A group of brain regions within the central nervous system that controls the sympathetic and parasympathetic systems, coordinating their actions on various physiological variables.

Question 28

Where do the sympathetic and parasympathetic systems originate?

Answer 28

The sympathetic system originates from the thoracolumbar outflow, while the parasympathetic system comes from the craniosacral outflow.

Question 29

What are the two main responses initiated by the central autonomic network?

Answer 29

The fight or flight response (sympathetic) and the rest and digest response (parasympathetic).

Question 30

Which brain region is a key part of the central autonomic network?

Answer 30

The hypothalamus.

Question 31

How does the hypothalamus relate to the thalamus?

Answer 31

The hypothalamus is located inferior and anterior to the thalamus.

Question 32

What are the five important roles of the hypothalamus summarized as “five Fs and one S”?

Answer 32

1. Food metabolism
2. Furnace (body temperature)
3. Fight response
4. Flight response
5. Fornication (reproductive behaviors)
6. Sleep-wake cycle (the S).

Question 33

What is the role of the amygdala in the central autonomic network?

Answer 33

The amygdala controls emotional responses and influences hypothalamic activity based on emotional states.

Question 34

What structures are involved in cardiovascular and respiratory control in the medulla?

Answer 34

The cardiovascular and respiratory centers, the nucleus of solitary tract, and the dorsal motor nucleus of vagus.

Question 35

How can the neocortex influence the autonomic nervous system?

Answer 35

Through conscious control methods like breathing exercises and mindfulness, allowing individuals to regulate heart rate and blood pressure.

Question 36

Which part of the cortex is essential for cognitive control over autonomic responses?

Answer 36

The prefrontal cortex, which is involved in problem-solving and rational thinking.

Question 37

What is the relationship between the spinal cord and the autonomic nervous system?

Answer 37

The spinal cord carries efferent outputs from both the sympathetic (thoracolumbar) and parasympathetic (craniosacral) systems.

Question 38

How do cognitive and emotional inputs affect the autonomic nervous system?

Answer 38

The hypothalamus integrates emotional input from the amygdala and cingulate cortex, as well as cognitive input from the prefrontal cortex, regulating autonomic responses accordingly.

Question 39

What is the main function of the Autonomic Nervous System (ANS)?

Answer 39

Homeostasis, the ability to maintain internal balance by adjusting physiological processes.

Question 40

How does the ANS maintain homeostasis?

Answer 40

By balancing the actions of the sympathetic and parasympathetic nervous systems.

Question 41

What are the two branches of the ANS?

Answer 41

The sympathetic nervous system and the parasympathetic nervous system.

Question 42

What does upregulating the sympathetic nervous system typically do?

Answer 42

It prepares the body for “fight or flight” responses.

Question 43

What is a negative feedback loop in the context of homeostasis?

Answer 43

A process where a stimulus is sensed, sent to a control center, which initiates an effector response to normalize the stimulus.

Question 44

How does the body regulate temperature through negative feedback?

Answer 44

Sensors detect temperature changes, signal the brain, which activates sweat glands to cool the body when temperature is too high.

Question 45

What is the reflex arc in the autonomic nervous system?

Answer 45

A pathway that includes a sensory receptor, afferent nerve fiber, synapse, and effector that responds to a stimulus.

Question 46

How does the autonomic reflex arc differ from somatic reflexes?

Answer 46

The autonomic reflex arc consists of two neurons (preganglionic and postganglionic), whereas somatic reflexes involve only one neuron.

Question 47

What are some examples of autonomic reflexes?

Answer 47

Baroreceptor reflex, micturition reflex, peristalsis reflex.

Question 48

What role do baroreceptors play in blood pressure regulation?

Answer 48

They sense stretch in the aorta and carotid arteries to help regulate blood pressure through autonomic responses.

Question 49

What types of sensory receptors are involved in autonomic reflexes?

Answer 49

Mechanoreceptors, chemoreceptors, nociceptors, and thermoreceptors.

Question 50

How do pupils respond to light changes?

Answer 50

Pupils dilate in low light via sympathetic activation and constrict in bright light via parasympathetic activation.

Question 51

What are some disorders associated with autonomic nervous system disruption?

Answer 51

Hypertension, orthostatic hypotension, autonomic dysreflexia, neurogenic bladder, and Horner’s syndrome.