Week 4.11 - The Embodied Brain

Question 1

How many neurons does an adult hermaphrodyte C. elegans have?

Answer 1

302

Question 2

C. elegans was first introduced as a model organism in…

Answer 2

1973

Question 3

What are methods of testing causality in the neural circuitry of the C. elegans?

Answer 3

• Genetic manipulation - Targeted cell elimination - Optogenetic stimulation

Question 4

Saccades are…

Answer 4

rapid eye movements to direct attention to discrete locations

Question 5

Smooth Pursuit is an eye movement for:

Answer 5

Locking the gaze on a moving target.

Question 6

How many eye muscles does each eye have?

Answer 6

6

Question 7

Which reflex is in response to the visual field moving?

Answer 7

Optokinetic Reflex follows the visual field (and Nystagmus brings the eye back)

Question 8

Motor neuron activity to the eye is primarily correlated with

Answer 8

Eye velocity

Question 9

Which effect is correct? A. Cold water in the ear will induce eye movement toward the ear B. Warm water in the ear will induce eye movement away from the ear

Answer 9

Both are correct

Question 10

Which of the following areas is not involved in vestibular processing?

Hippocampus, Vestibular nuclei, VPM of the Thalamus, Medial Superior Temporal Area

Answer 10

Hippocampus

Question 11

Adaptation of the vestibular ocular reflex is associated with which brain area?

Answer 11

Cerebellum (Purkinje cells and Parallel Fibers)

Question 12

Which vestibular signals can be ambiguous?

Answer 12

Translation & Tilt

Question 13

What are Sensorimotor behaviours? Give a few examples

Answer 13

A sensorimotor behavior is the ongoing relationship between sensory inputs and motor outputs.

For example, children can engage in instinctive sensorimotor behaviors (such as looking, sucking, grasping, and listening) .

Other examples are VOR and grasping and object.

Question 14

What are saccades?

Answer 14

a saccade is a quick, simultaneous movement of both eyes between two or more phases of fixation in the same direction. (used when you read for example)

Question 15

What is the Optokinetic reflex (OKR)?

Answer 15

This is a reflex that makes sure that when you are following a moving object with your eyes. You will occasionally ‘snap back’ a bit, that is called ‘nystagmus’. This is a reflex that can normally be suppressed.

> See this video <

Question 16

What is the function of the semicircular-canals and the vestibular system?

Answer 16

Indicate rotational acceleration of the head.

The vestibular system is a sensory system that provides information about motion, head position and spatial orientation.

The semicircular-canals are filled with endolymph. The endolymph will move through the canals as you move your head and move the cilia. When the cilia are pushed in one direction, depolarization of the connecting neurons will occur. If the cilia is pushed in the other direction, hyperpolarization of the connecting neurons will appear.