Lecture Exam 5 - The Autonomic Nervous System and Higher-Order Functions

What is the process by which short-term memory is converted to long-term memory?

Memory Consolidation

What are skill memories primarily concerned with?

Learned motor behaviors incorporated at an unconscious level

What happens to digestive and urinary functions during increased sympathetic activity?

Both digestive and urinary functions are typically reduced.

Which type of long-term memory fades with time and requires effort to recall?

Secondary memories

All parasympathetic neurons release which specific neurotransmitter?

acetylcholine (ACh)

What are autonomic plexuses?

nerve networks formed by mixing sympathetic and parasympathetic fibers.

What type of receptors are stimulated more by norepinephrine than by epinephrine?

Alpha receptors are stimulated to a greater degree by norepinephrine.

Why is the adrenal medulla considered a modified sympathetic ganglion?

contains ganglionic neurons with short axons

Where are nicotinic receptors found in the autonomic nervous system?

Found in ganglion cells of both sympathetic and parasympathetic divisions.

What describes the relative length of preganglionic and postganglionic fibers in the sympathetic division?

Preganglionic fibers are short, while postganglionic fibers are long

What is the concept of 'dual innervation' in the autonomic nervous system?

it means most vital organs are innervated by both ANS divisions.

Which of these is a response to increased sympathetic activity?

activation of energy reserves and higher respiratory rate is common

How do sympathetic and parasympathetic divisions typically interact regarding visceral effectors?

They usually exhibit opposite effects on the same visceral effector.

What is the primary effect of stimulating Beta-3 receptors?

Stimulation lipolysis, breaking down triglycerides in fat cells

What characterizes the cerebral cortex activity during deep sleep (NREM sleep)?

its activity is at its minimum during this sleep stage.

Which of these is not a type of autonomic ganglia where preganglionic fibers synapse?

The intramural ganglia are distinct from sympathetic division.

What is a key difference of short reflexes compared to long reflexes?

Short reflexes bypass the CNS entirely, with interneurons in ganglia.

What is a major effect of increased parasympathetic division activity?

Increased smooth muscle activity in the digestive tract occurs.

What key event occurs during Rapid Eye Movement (REM) sleep?

active dreaming takes place, with brain actively similar to being awake.

What is the primary function of collateral ganglia?

they innervate abdominopelvic tissues and various organs.

Which plexus is responsible for regulating heart rate, force, and blood pressure?

Cardiac Plexus

What is the primary function of the parasympathetic division?

it conserves energy and maintains the resting metabolic rate.

Which characteristic is shared by all higher-order functions?

they require the cerebral cortex for their complex operations.

What neurotransmitter is released by sympathetic preganglionic neurons at their synapses?

they release acetylcholine, which is always excitatory here.

Which beta receptor type triggers the relaxation of smooth muscles along the respiratory tract?

Beta-2 receptors cause relaxation of smooth muscles in airways.

Which dangerous toxin binds to muscarinic receptors and what does it do?

Muscarine targets parasympathetic divisions, binds to muscarinic receptors.

What is a visceral reflex?

A polysynaptic reflex initiated in viscera, providing motor responses.

What does 'autonomic tone' refer to in the autonomic nervous system?

It is the resting level of activity maintained by autonomic motor neurons.

Where are alpha-2 receptors found, and what is their primary effect?

They are found on sympathetic and parasympathetic neurons; stimulation is inhibitory and coordinates activities of ANS.

Which type of sympathetic ganglionic neuron releases acetylcholine?

Cholinergic neurons stimulate sweat glands and dilate blood vessels.

What is the effect of exposure to acetylcholine on nicotinic receptors?

causes excitation of the ganglionic neuron or muscle fiber.

What distinguishes the effects of muscarinic receptors from nicotinic receptors?

Muscarinic receptor effects are generally longer lasting and varied.

Where are muscarinic receptors primarily located?

On target cells of parasympathetic ganglion cells and some sympathetic ones.

Why are the effects of parasympathetic stimulation localized and short-lived?

Most ACh is inactivated rapidly at the synapse by AChE.

Where are the ganglionic neurons of the parasympathetic division typically located?

They are within or adjacent to target organs.

What is the primary control mechanism for sympathetic activation during a crisis?

The hypothalamus controls the overall 'flight or fight' response.

Where are the integrative centers for the autonomic nervous system located?

The hypothalamus houses these critical integrative centers.

What is a characteristic response to increased parasympathetic activity?

Decreased heart rate and blood pressure are typically observed.

What is the role of preganglionic fibers in the autonomic nervous system?

They transmit motor commands from the CNS to ganglionic neurons.

Which division of the ANS prepares the body for emergencies?

The sympathetic division activates the 'fight or flight' response.

What are the three components generally classified as higher-order functions?

Consciousness, learning, and intelligence

Which system operates without conscious instruction and controls visceral effectors?

The autonomic nervous system coordinates internal organ functions reliably.

What describes the relative length of preganglionic fibers in the parasympathetic division?

They are long, originating from brainstem and sacral segments.

Why do the effects of adrenal medulla secretions last longer than direct sympathetic innervation?

The hormones diffuse out of the bloodstream slowly over time.

Which neurotransmitters are primarily secreted by the adrenal medulla into the bloodstream?

Epinephrine (adrenaline) and norepinephrine (noradrenaline) are released.

How many cervical ganglia are typically found within the sympathetic chain?

3

Where are the preganglionic neurons of the sympathetic division located?

They are located in the lateral horns between T1 and L2 segments.

What is the effect of stimulating alpha-1 receptors, which are common in smooth muscle?

Stimulation of alpha-1 receptors primarily causes an excitatory effect.

What are the swollen segments on sympathetic ganglionic neuron telodendria called?

varicosities, releasing neurotransmitters broadly.

Most sympathetic ganglionic neurons release which neurotransmitter at their varicosities?

They primarily release norepinephrine and are called adrenergic neurons.