Lesson 7 - Reflexes and Reaction Time

Question 1

Is reaction time voluntary or involuntary?

Answer 1

Voluntary, unlike reflexes

Question 2

Reaction time is considerably more complex than reflexes as they involve __________

Answer 2

Higher brain functions

Question 3

Where does the delay for reaction time occur?

Answer 3

At the synapses between the different neurons involved

Question 4

What are the factors that affect reaction time?

Answer 4

1. Age (+/-)
2. Arousal (Fastest with intermediate level)
3. Distraction (Increases with reaction time)
4. Gender (Males generally have faster reaction times than females)
5. Practice (More practice decreases reaction time)
6. Errors (More errors lead to slower reaction times)
7. Fatigue (More fatigue leads to slower reaction times)
8. Punishment (-)
9. Drugs (Stimulants decrease reaction; depressants increase reaction time)
10. Warnings (Reaction time is faster with warning)

Question 5

It is an instantaneous response to a stimulus.

Answer 5

Reflex

Question 6

Are reflexes voluntary or involuntary?

Answer 6

Involuntary

Question 7

A reflex occurs via neural pathways in the nervous system known as __________

Answer 7

Neural Arcs

Question 8

What are the steps in reflexes?

Answer 8

1. Receptors detect a change
2. Sensory neurons carry information to the CNS
3. The CNS processes the sensory information
4. Motor neurons then send the information from the CNS to effector organs (ex: skeletal muscles)
5. The effector organ then produces a response appropriate to the stimulus that is perceived (for example pulling your hand away when you actually touch a sharp object)

Question 9

These are produced via single synapses between sensory axon and motor neurons.

Answer 9

Spinal reflexes

Question 10

This is the place where neurons connect and communicate with each other.

Answer 10

Synapse

Question 11

These are nerve cells that communicate information to the CNS and the rest of the body

Answer 11

Neurons

Question 12

This type of neurons help perceive a stimulus.

Answer 12

Sensory neurons

Question 13

This type of neurons are for coordinating an action.

Answer 13

Motor neurons

Question 14

This is a part of the neuron that carries information to and from the spinal cord.

Answer 14

Axon

Question 15

How many neurons do spinal reflexes use and what are they?

Answer 15

Two neurons: sensory and motor

Question 16

What are the different types of spinal reflexes?

Answer 16

1. Stretch (myotatic) reflex
2. Golgi tendon reflex
3. Crossed extensor reflex
4. Withdrawal reflex

Question 17

This refers to the contraction of a muscle in response to its passive stretching

Answer 17

Muscle stretch reflexes

Question 18

Where is the cell body of the sensory axon located to illicit a patellar reflex?

Answer 18

Dorsal root ganglion in the lumbar region of the spinal cord (L2 to L4)

Question 19

This is also known as the nociceptive flexion reflex

Answer 19

Withdrawal reflex

Question 20

Withdrawal reflex is important in __________ from harmful stimuli.

Answer 20

Protecting the body

Question 21

TRUE OR FALSE:
Flexor muscles are stimulated, causing the flexion of your leg towards the stimulus.

Answer 21

FALSE: Away from the stimulus*

Question 22

TRUE OR FALSE: There is an opposite reaction in the opposite leg to enhance postural support.

Answer 22

TRUE

Question 23

This is more complex than a regular myotatic reflex.

Answer 23

Pupillary reflex

Question 24

Pupillary reflex involves:

Answer 24

1. Additional cells
2. Interneurons
3. Four neurons

Question 25

These are neurons that help in integration of sensory information and motor activity

Answer 25

Interneurons

Question 26

TRUE OR FALSE: Pupillary reflex results in a shorter delay between stimulus perception.

Answer 26

FALSE: Longer delay*

Question 27

Pupillary constriction is referred to as __________.

Answer 27

Miosis

Question 28

Pupillary dilatation is referred to as __________.

Answer 28

Mydriasis

Question 29

This is characterized by rapid dilation of the ipsilateral pupil (by 1 to 2 mm) with a painful or startling stimulus

Answer 29

Ciliospinal reflex

Question 30

Contact with the cornea initiates 2 reflexes. What are they?

Answer 30

1. Blink (corneal) reflex 2. Tear production

Question 31

This is also known as the oculocephalic reflex or the doll’s eye reflex

Answer 31

Auditocephalogyric reflex

Question 32

Auditocephalogyric reflex is used to test what?

Answer 32

1. Cranial Nerves III, VI, and VIII 2. Overall brainstem function

Question 33

The gag reflex is also known as the __________.

Answer 33

Pharyngeal reflex

Question 34

It is an involuntary reflex involving bilateral pharyngeal muscle contraction and the elevation of the soft palate.

Answer 34

Gag reflex

Question 35

The gag reflex test is performed to test which cranial nerves?

Answer 35

CN IX and X

Question 36

What is the function of the gag reflex?

Answer 36

It attempts to eliminate foreign objects from the oral cavity.

Question 37

This has receptor organs in the skin rather than in muscle fibers

Answer 37

Skin reflex arcs

Question 38

FILL IN THE BLANKS: A __________ plantar reflex is called the __________ and is a sign of a disease of the __________ (corticospinal tract)

Answer 38

Positive; Babinski sign; Pyramidal