Midterm 2 chapters 6-8 Flashcards
(110 cards)
1
Q
Light can be thought of as …
A
- Particles of energy (photons)
- waves of electromagnetic radiation
2
Q
What is the smallest possible unit of light energy?
A
A photon
3
Q
What is an Electromagnetic Spectrum?
A
a continuum of energy produced by electric charges is radiated as waves
4
Q
How do Colours work?
A
certain objects reflect specific wavelengths of light and these wavelengths create a pattern of firing photorecepetors
5
Q
Where is light projected onto in the eye?
A
light is projected onto the retina
6
Q
what part of the retina represents the object we are looking at?
A
The fovea
7
Q
What focuses the image onto the retina?
A
The cornea
8
Q
What part of the eye is fixed?
A
the lenses
9
Q
What kind of photoreceptors line the retina?
A
Rods and Cones
10
Q
What part of the eye is rich in cone receptors?
A
the fovea
11
Q
What is the fovea specialized for?
A
it is specialized for seeing fine metals and colours
12
Q
What do photoreceptors do?
A
they convert light into nerve impulses aka transduction
13
Q
What is Transduction?
A
- when we take some outer stimulus (light or sound etc) and translate it into something the brain can understand which is an action potential
- the process of turning light into electricity
14
Q
What is an Opsin?
A
long protein strand
15
Q
What is Retinal?
A
a light sensitive molecule
16
Q
What helps improve eyesight?
A
Vitamine A and Retinal
17
Q
What are visual receptors?what happens at the visual receptors?
A
- outer segment
- where light acts to create electricity
- transduction occurs when retinal absorbs light
18
Q
When does Isomerization occur?
A
occurs when retinal changes shape, sticking out from opsin
19
Q
What is Visual Pigment Bleaching?
A
- when retinal separates from the opsin
- the retina then becomes lighter in colour
20
Q
What is Visual Pigment Regeneration?
A
- as light remains on, more and more of the retinal is detached, but more and more are regenerated
- opsin and retinal are rejoined
21
Q
What is the biggest difference between Rods and Cones?
A
Cones are Photopic (daytime vision)
rods are Scotopic (nighttime vision)
22
Q
Describe Cones
A
- found mostly in the fovea
- high-acuity (sharpness)
- colour vision
- needs a lot of light
23
Q
Describe Rods
A
- found mostly in periphery
- low-acuity (blurry)
- gray scale vision
- needs little light
- more convergence
24
Q
What is Convergence?
A
when we have more than one neuron all converging their inputs into one neuron
25
What is Selective Reflection?
some wavelength are reflected more than others
26
What is Transmission?
only some wavelengths pass through the object or substance
27
What are the two main theories that attempt to explain how we perceive colours?
1. trichromatic theory: colour vision depends on activity of three different colour receptor types (red, green, blue)
2. Opponent process theory: colour vision is related to opposing responses by blue-yellow and red green
28
What is Protanopia?
a colour deficiency where your missing the long wavelength (red) pigment
29
What is Deuteranopia?
a colour deficiency where your missing the wave medium length (green) pigment
30
What is Tritanopia?
possible missing the short wavelength pigment ?
| extremely rare
31
What is a soundwave?
the alternating increases and decreases in pressures creating soundwaves
32
What are the components of the Auditory Signal?
Frequency (pitch), Amplitude (volume), Complexity (timber)
33
What is Frequency?
the rate at which waves vibrate
34
What is Amplitude?
the intensity of the sound
35
What is Complexity?
most sounds are a mixture of frequencies
36
What amount of Hz are humans most sensitive to?
2,000 -4,000 Hz which is frequenct range for most speech sounds
37
what does the ear canal do?
helps amplify the sounds
38
what does the eardrum do?
pass vibration to the malleus, incus, stapes
39
What is the Vestibular System?
- it is needed for balance
- there is a canal for each plane we can be in
- tells your head where it is relative the the ground
40
Where is the Organ of Corti located?
the cochlea
41
What do the cilia do?
produce electrical signals
42
What kind of frequency sounds does the bases of basilar membrane code?
High frequency sounds
43
What are the two Primary Biaural Cues?
Interaural Time Difference (ITD)
Interaural Level Difference (ILD)
44
what is Interaural Time Difference?
based on the fact that there can be differences in the time it takes sound to arrive at one ear compared to the other
45
What is Interaural Level Difference?
localization for high frequency is accomplished using intensity difference
46
True or False: Cochlear nuclei are ipsilateral.
True
47
True or False: Damage to the ear itself, or auditory canal, or middle ear, or cochlear nucleus will lead to complete deafness in both ears
False: in one ear
48
What are the Main components of the Somatosensory System?
Nocioception
Hapsis
propioception
balance
49
What is Nocioception?
the perception of pain and temperature
50
What is Hapsis?
perception of objects using touch and pressure
51
What is Propiocpetion?
knowledge of the position of your limbs in space
52
What is balance?
controlled by the vestibular system in the inner ear
53
What does the superior colliculus receive information from?
The superior colliculus receives information from the retina
54
What does the inferior colliculus receive information from?
the inferior is receiving information from the superior olivary nuclei
55
What part of the thalamus receives auditory information?
The Medial Geniculate Nucleus (MGN)
56
What are neurons in the auditory cortex tuned based on?
they are tuned based on input and experience
57
Describe Rapidly adapting receptors
they respond quickly to sudden changes but adapt quickly
58
Describe slowly adapting receptors
a stronger stimulus takes longer to adapt
example: if you push down hard on your arm it will take a long time to adapt
59
What do sensory receptors respond to?
they respond to pressure, stretch, or vibration
60
Are Merkel receptors slow adapting or fast adapting?
merkel receptors slow adapting
61
Are Meissner Corpuscle fast adapting or slow adapting?
Meissner Corpuscle are fast adapting
62
What are the two main sensory Pathways?
Medial Lemniscus System and spinothalamic
63
What is medial lemniscus system?
large fibers, used for fine touch, proprioception
64
What is spinothalamic?
smaller fibers, used for pain a temperature
65
What are the 4 Homunculi?
fast adapting, slow adapting, proprioception, temp and pain
66
What are tactile Receptive fields?
neurons in the ventral posterior nucleus
67
What are receptive fields?
the location on the skin that, when stimulated, causes the receptor to fire
68
What is the Direct pathway model and what is a con of this theory?
researchers assumed that pain responses were created in receptors in the skin and sent directly to the brain
Problem: pain can occur when there is no stimulation on the skin ex phantom limb
69
What is the Gate control Model?
- pain signals enter the spinal cord are sent to S1
| - additional pathways can act as a "gate" to increase or decrease pain signals leaving the spinal cord
70
What do S-Fibers do?
carry pain signals from nocioceptors
71
What do L-fibers do?
carry information about tactile stimulation (no pain)
72
What do T-Cells do?
Transmit pain signals to the brain
they determine amount of pain experienced: more activity, more pain
73
Whats is central control?
signals coming from the brain to help reduce pain sensation
74
What neurotransmitter activates the same receptor as opiates? and how does it work?
Endorphins, they both block incoming pain signals
75
What does Macrosmatic mean? What are some examples?
species that have a very keen sense of smell for survival
Ex dogs, cats
76
What does Microsmatic Mean? and give an example.
Species who depend less on their sense of smell for survival
ex humans
77
What is detection threshold?
the lowest concentration at which an odour can be detected
78
What is recognition threshold?
odor has to be increased by a fact of 3 for quality to become apparent
79
Where do smell receptors reside in?
the Olfactory Mucosa
80
True or false: there are new olfactory receptors created every few weeks to replace the receptors that have deteriorated
True.
81
Whats are the 5 main qualities of taste?
Bitterness, sourness, sweetness, saltiness, umami (savoury)
82
What are taste buds?
receptors in tongue and oral cavity in clusters of about 50
83
What is Filiform?
shaped like cones and are found over entire surface giving it its rough appearance, they do not contain taste buds
84
True or False: action potentials from taste cells are transmitted via sensory nerves
False: action potentials from taste cells are transmitted via cranial nerves
85
What is Ageusia?
the inability to recognize common tastes
86
What is the posterior parietal cortex good for?
the posterior parietal cortex is good for integrating sensory information, and send it to the frontal cortex
87
What is the order of operation for the Motor Cortical Network?
Posterior sensory cortex sends goals
then the prefrontal cortex plans movements
then the premotor cortex organizes movement sequences
then the motor cortex executes actions
88
What is the posterior parietal cortex used for?
the posterior parietal cortex is used for attention (helps direct/disengage attention)
89
What is Proprioception?
Monitors limbs
90
What is Optic Ataxia?
damage to the posterior parietal area, difficulty reaching toward and grasping objects
91
What is Limb Apraxia?
when you can't perform purposeful movement in the absence of primary motor deficit
92
What does Ideomotor mean?
incorrect execution of the action
93
What does Ideational mean?
when you lose knowledge of the goal of the action
94
What is Pantomime?
asking the subject to generate a movement without an object present
95
What is Imitation?
asking the subject to imitate your movement
96
What is Ideomotor apraxia?
when people have deficits in their ability to plan or complete motor actions that rely on semantic memory . they can explain how to perform an action, but unable to "imagine" or act out a movement
97
What is Ideational/conceptual apraxia?
when people can't conceptualize a task and struggle to complete multistep actions
98
What does somatotopic Mean?
more cortex devoted to body parts that make complex movements
99
What 3 nuclei is the Basal ganglia comprised of?
caudate, putamen, globus pallidus
100
what does the basal ganglia play a critical role in?
the basal ganglia plays a critical role in managing the force of movements and motor learning
101
What does the cerebellum play a critical role in?
maintaining balance and posture, helps coordinate and accurately time motor output
102
What happens when someone has a cerebellar lesion?
do not adjust movements as easily
103
What are the 4 descending motor pathways?
two dorsolateral
- corticospinal
- corticorubrospinal
two ventromedial
-corticospinal
cortico-brainstem-spinal tract
104
What is a Corticospinal dorsolateral tract?
What does it control?
descend through the medullary pyramids, then decussate
it controls the wrists, hands, fingers, toes
105
What is a corticorubrospinal dorsolateral tract?
what does it control?
synapse at red nucleaus and cross before the medulla
it controls some face muscles and distal muscles of arms and legs
106
What is a cotricospinal ventromedial tract?
descends ipsilaterally, axon branch and innervate interneuron circuits bilaterally in multiple spinal segments
107
what is cortico-brainstem-spinal ventrolmedial tract?
interacts with various brainstem structures and descends bilaterally carrying information from both hemispheres
108
What are the differences between dorsolateral and ventromedial?
dorsolateral terminates in one contralateral spinal segment, controls distal muscles, and controls limb movements
ventromedial is bilateral innervation, controls proximal muscles, posture and whole body movement
109
What are muscle spindles?
they are embedded in muscle tissue, they detect changes in the muscle length
110
What are golgi tendon organs?
embedded in tendons, detect muscle tension
