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Flashcards in Reflexes Deck (16)
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1
Q

What is a reflex?

A

A stereotyped, involuntary and rapid response to a stimulus.

2
Q

What is integration?

A

The computational process by which an individual neuron processes its synaptic inputs and converts them into an output signal

3
Q

Which neurones are responsible for integration?

A

Interneurones

4
Q

What are the neural components of a reflex?

A
Sensory receptors
Afferents
Integration (by interneurones)
Efferents
Effectors
5
Q

What is the function of the stretch / myotatic reflex?

A

To maintain posture and adjust the degree of muscle contraction.

To prevent tearing of muscle.

6
Q

Are interneurones found in the CNS, PNS or both?

A

Exclusively in the CNS. E.g., in the spine, the somata are found in the grey matter. Reflexes can be cranial or spinal.

*Also in the enteric nervous system.

7
Q

What is a monosynaptic reflex?

A

A simple reflex that involves transmission of information from a sensory neurone to the appropriate motor neurone across a single synapse in the spinal cord.

E.g. the knee-jerk reflex (patellar).

8
Q

What is a polysynaptic reflex?

A

A reflex that involves transmission of information from a sensory neurone to interneurones in the CNS, which relay the integrated impulse to appropriate motor neurones.

Most reflexes are polysynaptic.

E.g. pupillary reflex.

9
Q

What morphology do interneurones have?

A

Multipolar morphology.

10
Q

Is the patellar reflex ipsilateral or contralateral?

A

Ipsilateral

11
Q

Is the crossed extensor reflex ipsilateral or contralateral?

A

Contralateral

12
Q

What is a contralateral reflex? What about ipsilateral?

A

A reflex which occurs on the opposite side of the body from the stimulus.
Branches of the afferent nerve fibers cross from the stimulated side of the body to the contralateral side of the spinal cord.
Ipsilateral - same side

13
Q

Is the pupillary reflex polysynaptic or monosynaptic?

A

Polysynaptic

14
Q

Is the pupillary reflex a spinal reflex or a cranial reflex?

A

Cranial

15
Q

Is the pupillary reflex an autonomic reflex or a somatic reflex?

A

Autonomic

16
Q

If light is shone into the right eye, how will the diameter of the right pupil change? What about the left?

A

Both pupils will decrease in diameter.