CH2 Sensation and Perception

Question 1

Signal Detection Theory

Answer 1

Our perception of stimuli changes due to internal and external context. i.e Someone saying your name

Question 2

Cells for Shape Vision

Answer 2

Parvo cells

Question 3

Bottom-up processing

Answer 3

Data-driven from stimuli and environment build up image to decide what it is

Question 4

Inner ear steps/parts

Endolymph? Perilymph?

Vestibule?

Semicircular canals?

Answer 4

1. Vibrations from the stapes push the Oval window which moves fluid in the Cochlea contains the organ of Corti composed of thousands of hair cells. The movement of the hair cause K+ and Ca2+ channels to open in the hair an cause an action potential that can travel to the brain
2. Endolymph (fluid) is found in the membranous labyrinth. Perilymph is found in the bony labyrinth (bone)
3. Vestibule: contains the utricle and saccule which contain otoliths (hair cells) sensitive to linear acceleration
4. Semicircular Canals: Sensitive of rotational acceleration. Ampulla (hair cells) moved by the resistance of endolymph

Question 5

Gestalt Principles

Answer 5

Question 6

Difference Threshold

Answer 6

Minimum difference that allows for differentiation of stimuli of higher or lower magnitude. Weber’s Law applies this as a percentage difference

Question 7

Middle ear steps/parts

Answer 7

1. Vibrations from the tympanic membrane are transmitted by the ossicle: - Malleus - Incus - Stapes
2. Eustachian tube connected to the nasal cavity equalizes pressure b/w middle ear and environment

Question 8

Optic Chiasm

Answer 8

Hear the right and left optic nerve cross each other

Question 9

Anatomy of Eye: Cornea, Iris, Lens, Ciliary Muscle, Ciliary Body, Retina

Answer 9

• Cornea: Gathers and filters incoming light
• Iris: Colored part of the eye (composed of the 2 muscles that dilate or contract the pupil)
• Lens: Behind the iris, controls the refraction of light towards the retina
• Ciliary Muscle: Can move the lens for accommodation
• Ciliary Body: produces aqueous humor which drains through the canal of Schlemm
• Retina: contains the photoreceptors

Question 10

Parallel Processing

Answer 10

Using vision and its many cells to identify an object

Motion (magno)

shape (parvo)

color (cones 60%R 30%G 10%B)

Question 11

Absolute Threshold

Answer 11

Minimum stimulus energy that is need to activate the sensory system (Action Potentials

Question 12

Threshold of Conscious Perception

Answer 12

Stimulus that reaches the CNS but does not trigger the higher-order brain that controls conscious and attention

Question 13

Top-down processing

Answer 13

Driven by memories and expectations. Quick recognition of an object without the need to identify its small parts

Question 14

Cells for Motion Vision

Answer 14

Magno cells

Question 15

Outer ear steps/parts

Answer 15

1. Sound reaches the external auditory canal 2. The sound waves to the tympanic membrane 3. The frequency of the sound waves determines the rate of tympanic vibration

Question 16

Response Bias

Answer 16

response based on external factors or tendencies implied in the situation.

Question 17

Macula and Fovea

Answer 17

Macula (rods) there are more rods than cones Fovea (cones)

Rods are slow

Cones are fast

Question 18

Bipolar cells and Ganglion Cells.

How do rods pass info.

Answer 18

They synapse together to form the optic nerves. Cones and rods are connected by bipolar cells.

Rods are always on, when light hits they become off and pass info to bipolar cells which pass to ganglion cell which passes to the optic nerves

Question 19

Nociceptors

Answer 19

a sensory receptor for painful stimuli

Question 20

Vision Processing In Eyes to Brain

Answer 20

Question 21

What’s the Auditory Space

Answer 21

The area around the head used to perceive sounds.

• Distance
• Altitude
• Azimuth (angle)

loudness is not part of it

Question 22

Place Theory

Answer 22

Perception of pitch, how high or low a tone is.

High vs low frequency

Question 23

Motion Parallax

Answer 23

objects in the foreground are perceived as moving faster than objects in the background

used to perceived both depth and motion

Question 24

Monocular Depth Cues

• Linear perspective
• Height in plane
• Relative Size
• Interposition
• Light and Shadow
• Texture gradients

Answer 24

Question 25

Binocular Depth Cues:

• Convergence
• Retinal Disparity

Answer 25

• Convergence: Angle of eye changes as the distance changes (move inward as the object is closer) used as a distance indicator
• Retinal Disparity: Distance b/w our eyes causes 2 different images of the same object, making two 2d images into one 3d image