Sensation and Perception (2)

Question 1

Sensation

Answer 1

conversion of physical, electromagnetic, auditory, and other info from the internal and external environment into electrical signals in the nervous system.

Question 2

Perception

Answer 2

processing of sensory information to make sense of its significance.

Question 3

Photoreceptors

Answer 3

responds to electromagnetic waves in the visible spectrum (vision)

Question 4

Nociceptors

Answer 4

responds to painful or noxious stimuli (somatosensory)

Question 5

Olfactory receptors

Answer 5

responds to volatile compounds (smell)

Question 6

Taste receptors

Answer 6

respond to dissolved compound (taste)

Question 7

Threshold

Answer 7

the minimum stimulus that causes a change in signal transduction

Question 8

Absolute threshold

Answer 8

minimum of stimulus energy that is needed to activate a sensory system.

Question 9

The threshold of conscious perception

Answer 9

minimum of stimulus energy that will create a signal large enough in size and long enough in duration to be brought in awareness.

Question 10

difference threshold or just-noticeable difference (jnd)

Answer 10

the minimum difference in magnitude between two stimuli before one can perceive this difference.

jnd for sound frequency is more accurately quantified as 0.68%.

Question 11

Weber’s Law

Answer 11

states that there is a constant ratio between the changes in stimulus magnitude needed to produce a jnd and the magnitude of the original stimulus.

Question 12

Signal detection Theory

Answer 12

focuses on the changes in our perception of the same stimuli depending on both internal and external context.

Question 13

Cornea (eye)

Answer 13

gathers and focuses incoming light

Question 14

pupil

Answer 14

allows passage of light from anterior to posterior chamber

Question 15

Iris

• Dilator pupillae
• Constrictor pupillae

Answer 15

Iris: controls the size of the pupil

Dilator pupillae –> opens the pupil under sympathetic
Constrictor pupillae –> constricts pupil under parasympathetic.

Question 16

Cilary body

Answer 16

produces aqueous humor; accommodation of the lens

Question 17

Lens

Answer 17

refracts the incoming light to focus it on the retina

Question 18

Retina

Answer 18

detects images

Question 19

Sclera

Answer 19

provides structural support.

Question 20

Cones and Rods

Answer 20

Cones –> color vision
Rods –> contains a single pigment called rhodopsin permits for night vision.

Mnemonic:
Cones for COLOR
Rods for RAAT

Question 21

Optic nerve

Answer 21

rods and cones are connected with bipolar cells, bipolar cells synapse with ganglion cells, which group together to form Optic nerve.

Question 22

Visual Pathway

Answer 22

Cornea –> pupil –> vitreous humor –> retina (rods + cones to bipolar cells to ganglion cells) –> optic nerve –> optic chasm –> optic tract –> LGN (lateral geniculate nucleus in thalamus) –> radiation through parietal and temporal lobe –> visual cortex in occipital lobe

Question 23

Parallel Processing

Answer 23

Ability to simultaneously analyze and combine information regarding color, shape, and motion.

Question 24

Parvocellular cells

Answer 24

cells that detect shapes, very high color spatial resolution.

only work with stationary or slow-moving objects.

Question 25

Magnocellular cells

Answer 25

cells that detect motion, because it has a high temporal resolution.

Question 26

Tymphanic membrane ( eardrum)

Answer 26

vibrates as sound waves enter the ear. Also divides outer and inner ear.

Question 27

Ossicles (middle ear)

Answer 27

consists of malleus (hammer), incus (anvil), and stapes (stirrup).

Question 28

Bony labyrinth

Answer 28

contains the cochlea, vestibule, and semicircular canals These structures contain endolymph.

Question 29

Endolymph

Answer 29

found in the membranous labyrinth

Question 30

Perilymph

Answer 30

found in bony labyrinth. transmits vibrations from the outside world and cushions the inner ear structures.

Question 31

Cochlea: spiral-shaped divided into 3 parts called scalae

Answer 31

middle scalae: houses hearing apparatus called the organ of Corti, rests on the basilar membrane. The organ of Corti consists of hair cells which bathe in endolymph.

Question 32

Stereocilia

Answer 32

long tufts on the surface of hair cells. As vibration reaches to the basilar membrane, stereocilia go back and forth. This motion opens ion channels, causing receptor potential.

Question 33

Auditiory Pathway

Answer 33

pinna --> external auditory canal --> tympanic membrane --> malleus --> incus --> stapes --> oval window --> perilymph of cochlea --> basilar membrane --> hair cells --> vestibulocochlear nerve --> brain stem --> MGN of thalamus --> auditory cortex (temporal).

Question 34

Vestibule

Answer 34

a portion of the bony labyrinth, contains utricle and saccule. Utricle and Saccule--> sensitive to linear acceleration, part of balancing apparatus determine orientation in 3D. contained modified hair cells covered with otolithus.

Question 35

Semicircular canals

Answer 35

sensitive to rotational acceleration. They arranged perpendicular to each other. Hair cells are located in the ampulla. When the head rotates, the endolymph in the semicircular canal resists motion, bending the hair cells, sending signals to the brain.

Question 36

Place Theory

Answer 36

states that the location of hair cells on the basilar membrane determines the perception pitch when that hair cell is vibrated. High-frequency pitch cause vibration close to oval window Low-frequency pitch cause vibration away to oval window

Question 37

Pacinian corpuscles

Answer 37

respond to deep pressure and vibration

Question 38

Meissner corpuscles

Answer 38

respond to light touch

Question 39

Merkel cells

Answer 39

respond to deep pressure and texture

Question 40

Ruffini cells

Answer 40

respond to stretch

Question 41

free nerve ending

Answer 41

respond to pain and temperature

Question 42

Physiological zero

Answer 42

normal temp of the skin to which objects are compared to determine if they feel warm or cold

Question 43

Gate theory of pain

Answer 43

states that pain sensation is reduced when other somatosensory signals are present.

Question 44

Bottom-up processing

Answer 44

recognition of objects by parallel processing and feature detection. slower but less prone to mistake.

Question 45

Top-down processing

Answer 45

recognition of objects by memories and expectations. Faster but more prone to mistakes.

Question 46

Perceptual organization

Answer 46

refers to our synthesis of stimuli to make sense of the world including the integration of depth, motion, form, and constancy.