Lecture 4

Question 1

Name the 3 landmarks of the brain

Answer 1

1. Central sulcus
2. Sylvian (lateral) fissure
3. Parieto-occipital sulcus

Question 2

Describe:

The central sulcus

Answer 2

Separates the frontal lobe from the parietal lobe

Question 3

What is anterior to the central sulcus? What is posterior to the central sulcus?

Answer 3

Anterior: M1 (Primary motor cortex)
Posterior: S1 (Primary somatosensory cortex)

Question 4

Describe:

The Sylvian (lateral) fissure)

Answer 4

Separates the parietal lobe and the temporal lobe

Question 5

Describe:

The parieto-occipital sulcus

Answer 5

Separates the occipital lobe from parietal lobe, and occipital lobe from temporal lobe

Question 6

Describe:

The occipital lobe

Answer 6

• Smallest lobe, but contains the most neurons
• Devoted to processing vision; sometimes called visual cortex
• Contains primary visual cortex (V1)
• Contains three-dozen distinct extrastriate visual regions (i.e. V5/MT)

Question 7

What is V1? Where is it located?

Answer 7

V1: Primary visual cortex
Located on the medial (middle) surface of each hemispheres (squished in between the two hemispheres)

Question 8

What does V1 do?

Answer 8

Supports initial processing visual inputs
Supports coding of color, lumiannce, spatial frequency, orientation, and movement of visual stimuli

Question 9

Define:

Cortical magnification

Answer 9

Expansive V1 dedicated to central vision is more than expansive V1 peripheral vision

Question 10

Define:

Extrastriate

Answer 10

Beyond visual cortex

Question 11

What is V5/MT? What does it do?

Answer 11

Extrastriate region dedicated to capturing motion, helps detect motion

Question 12

David Hubel with Torsten Weisel won the Nobel Prize based on identifying neuron types. They did this in a cat experiment, explain the experiment

Answer 12

Directly measured the activity of one neuron in response to an activity
Measuring receptance field of neuron using a light

Question 13

How does a simple V1 neuron differ from a complex V1 neuron?

Answer 13

Simple V1 neuron is active to specific orientation of stimulus, the stimulus has to be in a very specific orientation to be activated
Complex V1 neurons have a wider field of detection

Question 14

What is binocular vision?

Answer 14

The ability to determine depth and distance

Question 15

True or False:

Babies have binocular vision

Answer 15

False
Binocular cells (specialized neurons) develop at a specific timepoint in an infant’s life

Question 16

Describe:

Cortical Blindness

Answer 16

A lesion/damage to the visual cortex that will cause a scotoma in the contralesional visual field

Question 17

Define:

Scotoma

Answer 17

Like a black hole in the visual field, the individual cannot see that area as neurons of that area is damaged event though the eye is functioning fine

Question 18

In cortical blindness:

Why does a damage to the visual cortex cause a scotoma in the contralesional visual field?

Answer 18

Visual fields are crossed; information from left is processed in the right hemisphere and vice versa

Question 19

How is cortical blindness diagnosed?

Answer 19

Evaluating MRIs: Looking for extremely dark or extremely light areas for information

Question 20

What fills areas that suffered strokes?

Answer 20

Cerebrospinal fluid

Question 21

Define:

Blindsight

Answer 21

One can respond to stimulus without being aware of them

Question 22

What is the extrageniculate pathway?

Answer 22

Vision that supports movement and doesn’t require on V1