Lecture 7 Eye limb coordination

Question 1

Eye limb coordination

Answer 1

Motor act of coordinating the eyes and limb - moving them both toward the same target in unison

Question 2

Eye movements are ______ with goal directed hand movements

Answer 2

tightly coupled

Question 3

When reaching or intercepting an object

Answer 3

Humans naturally direct their eyes to the object

Question 4

How do eye movements improve hand accuracy?

Answer 4

Through a combination of visual with efference-copy information

Question 5

The information exchange between eye and hand movement system is

Answer 5

Bidirectional.
–> Execution of a concurrent hand movement can result in improvements in eye movements

Question 6

How long does a saccade take?

Answer 6

20-40ms

Question 7

When we track something with our eyes how do they move?

Answer 7

They track the target and then jump with a saccade and then track again.

Question 8

Eye foot coordination

Answer 8

When walking, gaze consistently looks 1.5s ahead to optimise vision of the environment that is traversed so they can walk efficiently and stable.

Question 9

How do we encode information for eye hand coordination?

Answer 9

With reference frames and coordinates systems

Question 10

Egocentric reference frames

Answer 10

Representing an object relative to yourself

Question 11

Allocentric Reference Frames

Answer 11

Representing an object relative to an external object

Question 12

The hippocampus has more _____ coded information

Answer 12

Allocentrically

Question 13

Gaze

Answer 13

The direction of your eye. Where you are looking in space. The main purpose of gaze shifts is to redirect the fovea toward a new object of regard

Question 14

Retinal/Eye fixed/Eye centered

Answer 14

Information is coded relevant to your looking direction

Question 15

Shoulder-arm geometry

Answer 15

The reference frame for a limb is the torse. The centre of shoulder rotation is significantly shifted from that of the head, which in turn is shifted with respect to that of the eye

Question 16

Forward Models

Answer 16

A network that predicts the sensory consequences of a given motor command in an environment

Question 17

The ___ and ___ seem to be more involved in reaching movements

Answer 17

Premotor cortex and M1

Question 18

How do we make a decision in a sports related context such as do I hit the ball to the left or to the right? Or do I block the ball instead (volleyball)

Answer 18

The brain specifies multiple possible actions in parallel up to the level of motor preparation while a variety of biasing influences cause one specific response program to prevail.

Question 19

How does continous control work?

Answer 19

So we can still change or update our movements even after they have begun. We change our mind as information is still being collected after the initial decision to move towards a certain thing

Question 20

How long does it take for a correction to kick in?

Answer 20

About 100ms. It is not reflexive

Question 21

Looking ahead for forthcoming actions

Answer 21

We need to be able to look ahead at a sequence of movements