senses IV

Question 1

Surfaces of objects do what with wavelengths?

Answer 1

Surfaces of objects absorb some wavelength and reflect others

Question 2

What is doen with non-absorbed light?

Answer 2

reflected and picked up by eyes

Question 3

How can reflectance of light be measured?

Answer 3

photospectrometer

Question 4

Lens of the human eye absorbs UV and with increasing age……

Answer 4

also short wavelengths (violet, blue)

Question 5

What are the proven dimensions of colour vision in animals?

Answer 5

dichromacy, trichromacy, tetrachromacy

Question 6

Trichromats discriminate more colours than ….

Answer 6

dichromats

Question 7

What is a trichromat?

Answer 7

seeing 3 colours

Question 8

what is a dichromat?

Answer 8

seeing 2 colours

Question 9

What are the three types of wavelength?

Answer 9

s, m and l-cones

Question 10

How does colour vision defects affect each sex?

Answer 10

8% of males

0.5% of females

Question 11

Which cone opsin genes are on the X chromosome?

Answer 11

M- and L-cone

Question 12

which cone opsin gene is on chromosome 7?

Answer 12

S-cone

Question 13

What is Protanomaly?

Answer 13

reduced sensitivity to red light

Question 14

WHat is deuteranomaly?

Answer 14

reduced sensitivity to green light (MOST COMMON)

Question 15

what is tritanomaly?

Answer 15

reduced sensitivity to blue light (RARE) – tritanopia: lacking the short-wavelength

Question 16

Normal vision requires what?

Answer 16

at least one L, one M and one S pigment gene

Question 17

What is trichromatic vision a result of?

Answer 17

gene duplication in primates (therefore close overlap of L- and M-cone spectral sensitivities).
Optimal to detect and distinguish ripe fruit.

Question 18

What does colour vision result froM?

Answer 18

different types of opsin with different spectral sensitivities

Question 19

What is a Spectrally opponent cell

Answer 19

Spectrally opponent cell: a visual receptor cell that has opposite firing responses to different regions of the spectrum

Question 20

Who discovered the spectral composition of daylight?

Answer 20

Isaac Newton

Question 21

What is colour constancy?

Answer 21

Ability to recognising colours under different illuminations

Question 22

What is the Kanisza illusion?

Answer 22

solid triangle pointing upwards that is lighter than the background, which occludes an inverted triangle pointing downwards, and a set of black discs which are also occluded by the solid bright white triangle that points upwards. Surprisingly, none of these shapes are actually present in the figure.

Question 23

What is sound?

Answer 23

pressure waves, movement of air particles set in motion by vibrating structure

Propagates in three dimensions, alternating compression and rarefaction of air, molecules move back and forth from regions of high pressure to low pressure.

Question 24

What are measures of sound?

Answer 24

– frequency (reciprocal of wavelength, perceived as pitch) and amplitude (loudness), phase and waveform

Question 25

What does movement fo the ossicles do?

Answer 25

pushes the oval window which moves the fluid inside the scala tympani
One the other end of the cochlea the round window bulges outward

Question 26

What is the round window?

Answer 26

A membrane separating the cochlear duct from the middle-ear cavity.

Question 27

What are the auditory receptors?

Answer 27

Inner (IHC) and outer (OHC) hair cells

Question 28

What does bending of the stereocilia do?

Answer 28

Bending of the stereocilia (right) opens large, nonselective ion channels, allowing K+ and Ca2+ to enter the stereocilia. The resulting depolarization opens Ca2+ channels in the cell’s base, causing the release of neurotransmitter to excite afferent nerves (Hudspeth, 1992).

Question 29

what does each superior olivary nuclei of the brainstem do?

Answer 29

receives inputs from both cochlear nuclei for first stage of binaural analysis of sound-source location.

Inferior colliculi are located in the dorsal midbrain.

Medial geniculate nuclei of the thalamus

Question 30

What do the paths of the cochlear nucleus do?

Answer 30

One path from each cochlear nucleus goes to both superior olivary nuclei, so they both receive inputs from both right and left cochlear nuclei. This bilateral input is the first stage in the CNS at which binaural (two-ear) effects are processed;

Question 31

What does the Jeffress model show?

Answer 31

Jeffress model of how the brain codes latency differences between sound heard by right and left ear by coincidence detection