EXAM 1 REVIEW TEST Flashcards
1
Q
What is the Thalamic Nuclei for the Auditory system
A
- Medial geniculate body
2
Q
What is the Thalamic Nuclei for the Visual system
A
- pulvinar and lateral geniculate nucleus
3
Q
What is the Thalamic Nuclei for the Somatosensory system
A
-Ventral-Lateral Area
4
Q
What is the Thalamic Nuclei for the Olfactory system
A
- Mediodorsal nucleus
5
Q
What is the Thalamic Nuclei for the Gustatory system
A
-Ventral Posteromedial nucleus
6
Q
Explain sensory deprivation
A
- Your brain is so dependent upon sensory stimulation
- it is primed to interpret and analyze environmental stimuli so when deprived of this information/ stimulation, the brain makes it up
7
Q
What is a Homunculus?
Are there plural?
Who discovered this concept?
A
- the homunculus refers to a sensory map of the human body ( topographic representation)
- it refers to a sensory map of the human body and shows a depiction of what we would look like if our body parts grew in proportion to how much sensation we feel with them
- Wilder Penfield
8
Q
What are the two kinds of Homunculi
A
- Motor and Sensory
9
Q
What are the 5 ways to study asymmetry in patients
A
- Brain stimulation
- Double Dissociation
- Split Brain and Commissary patients
- Split face test
- Wada Test
10
Q
What is Brain Stimulation?
What happens with stimulation of the RH and LH?
A
- Wilder Penfield
- stimulating certain brain regions produces certain behaviour
- found that the RH produces interpretative and experiential responses that are not produced by stimulation of LH
example- Deja Vu, fear, sense of dreaming, religious thoughts/feelings - RH stimulation also produces disruptions in the judgements on line orientation, facial expressions and STM for faces
- LH accelerated speech production/ responses or block speech if the individual is already engaged
11
Q
What is Double Dissociation
A
- uses case studies, neuroimaging and neuropsychological testing to identify the neural substrate of a PARTICULAR brain function
- 2 manipulations that each have different effects on 2 different variables
(one manipulation affects the 1st variable and not the 2nd and the other manipulation affects the 2nd not the 1st)
12
Q
Left Hemisphere lesions in right handed participants consistently produce deficits in what
A
- language functions
13
Q
removal of the anterior part of left temporal lobe shows what deficits?
A
- superior intelligence
- significant deficits on tests of verbal recall and memory quotient (verbal memory)
- over time there will be a general decrease in intelligence ratings, and a further decrease in verbal memory
14
Q
right temporal lesion produces what deficits?
A
- low scores on recall of complex drawings
- overtime there is decrease in performance IQ and nonverbal memory
15
Q
What is the Split Brain and Commissurotomy procedure?
Who first performed this procedure?
A
- When medication fails to help epileptic seizures, cutting of the commissure (CC) in a Commissurotomy procedure will disconnect the two hemispheres
- William Van Wagen 1940
16
Q
How do we connect both sides of the visual world
A
information presented to the LVF travels first to the RH and then through the corpus callosum to the LH
17
Q
What happens when the LH of a split brain patient has access to information
A
- it can initiate speech and communicate the information
18
Q
What happens when the RH of a split brain patient has access to information
A
- good recognition abilities but lacks the initiation of speech because it lacks access to the speech mechanisms in the LH
- can draw or write it down
EXAMPLE
shown spoon to LVF they will say “I see nothing”
19
Q
Explain the Interpreter Test and results
Who created it?
A
split brain patients are presented with two images (one for each hemisphere) then asked to select a third image that matches the scene
- each hand will choose appropriate to the scene visible to the corresponding visual field (Left hand will choose what was seen in LVF)
- when asked to explain the choice the patient will describe the image selected by the right hand in terms of the scene on the right
- this suggest that only the LH is engaged in the interpretation of the situation
- Michael Gazzaniga
20
Q
What is the Split Face test
A
Shows RH specialization for recognizing faces
- Pictures of faces split down the middle and recombined in improbable ways
- when presented to split brain patient, the patient is unaware because they are only seeing the normal half in each hemisphere
- when u ask them which was the original group of faces they will say the one that was shown in the LVF or RH
21
Q
What is the WADA test
A
- Carotid Sodium Amobarbital injection
- this drug anesthetizes the hemisphere
- L carotid artery injection anesthetizes the L hemisphere and vice versa
- Patients are aphasic after (dont remember)
22
Q
What happens with a Carotid Sodium Amobarbital injection to the left carotid artery
A
- patient cannot speak, move R arm, no RVF
- RH nondominant but aware for speech so they cannot report on the experience later
23
Q
What happens with a Cartoid Sodium Amobarbital injection to the right cartoid artery
A
- sensory and motor disturbances but no speech disturbances
- UNLESS they are RH dominant for speech
24
Q
What is lateralized in the brain? ( what are the two distinct forms of functional lateralization in the brain)
A
- Specialization theories - unique functions for each hemisphere (LH bias for self interaction, RH integrated)
- Interaction models - both hemispheres have the capacity to perform all functions but dont (cooperation between hemispheres)
25
What are the three interaction models
1. The two hemispheres function simultaneously but work on different aspects of processing
2. Although the two hemispheres have the capacity to perform a given function they inhibit or suppress each other activity
3. Either the two hemispheres receive information preferentially and thus perform different analysis simultaneously or some mechanism enables each hemisphere to pay attention to specific types of information thus leading to different hemispheric analyses
26
What is the function of the posterior hippocampus?
memory and spatial navigation
27
What is the function of the anterior hippocampus?
anxiety related behaviours
28
What is Handedness associated with ?
- cerebral asymmetry and lateralization of the brain
- also associated with differences with cerebral blood flow, anatomical asymmetries and lateralization of functions like language
29
When does hand preference begin
10 weeks of fetal development
30
What are the four categories of theories for left handed vs right handedness
1. environmental
2. anatomical
3. hormonal
4. genetic
31
What percent of the population Is left handed
10%
32
What three subcategories do environmental theories break down into
1. Utility: mothers are more likely to hold infant in the left hand so they are closer to the mothers heart and so the mothers right hand is free to do other tasks
2. Reinforcement: for centuries children have been taught to write with their right hand, but modern education is not accepting left handedness (prevalence has not gone up)
3. Damage: there may be some genetic bias toward being right handed. suggesting that being left handed is the result of a genetic anomaly or stressful in-utero development
(ex. 18% of twins are left handed which is close to twice that of regular population 10%)
33
What are the two subcategories for the anatomical theories of handedness?
1. enhanced maturation: the LH generally shows enhanced maturation and greater development which may influence handedness
2. Those seen in nature:
- this theory points out that the heart is on the left side of the chest, the temporal lobe is larger on the left, and the areas that influence birdsong are found in the LH of brain
- LH dominance for language and motor control may just be another manifestation of this trend
(the research on these theories is little to none)
34
what are the hormonal theories of handedness
- exposure to different levels of testosterone early in life could impact cerebral organization and asymmetry
- testosterone is generally inhibitory on development
- testosterone acts on the LH of the brain leading to great development of the RH and Left handedness in some individuals
STUDIES EXAMINING AMNIOTIC FLIUD HAVE NOT SUPPORTED THIS THOERY
35
What are the genetic theories of handedness
there could be a dominant gene for handedness
- a more widely researched variant suggests the dominant gene encodes left hemisphere speech ( if there was a r handed gene it would also encode LH speech
- Genes that favour left hemisphere speech also favour an advantage in motor control of the right hand
36
What are the sex differences in Symptomatology
women- affective and cognitive
| men- more motor deficits
37
What are the 5 classes of cognitive behaviours Kimmura examined
1. motor skills
2. spatial analysis
3. mathematical aptitude
4. perception
5. verbal abilities
38
What are the tasks favouring women
- mathematical calculation
- verbal memory (recall)
- object memory (where this are)
- fine motor skills, coordination
- perception (rapidly matching)
39
What are the tasks favouring men
- mathematical reasoning
- geometric form perception
- mental rotation
- target-directed motor skills
- visual imaging
40
Sex differences in motor skills
- men are superior at target throwing and catching
- females have superior fine motor skills such as the peg board
- differences present early in like, as young as 3
41
Sex differences in spatial analysis
Men
- generally better at spatial tasks requiring mental rotation and navigation
- generally quicker at learning spatial navigation tasks
Women
- improve on mental rotation tasks when block figures are replaced by human shapes in different postures
- the human figure rotation task
- women better at identifying which objects have been moved or displaced, better recall for landmarks
the sex differences in spatial ability tasks is not in spatial information its the difference related to what you do with the info
42
Sex differences in mathematical Aptitude
```
Men
- mathematical reasoning
Females
- computation
- much better at reading (3x more than that of men in math)
```
43
Sex differences in brain structure that favour women
- larger language areas
- larger medial paralimbic areas
- larger lateral frontal areas
- greater relative amount of gray matter
- more densely packed neurons in temporal lobe
- more gyri
- thicker cortex
44
Sex differences in brain structure that favour men
- larger medial frontal areas
- larger cingulate areas
- larger amygdala and hypothalamus
- larger overall white matter volume
- larger cerebral ventricles
- larger right planum parietale
- more neurons overall
- larger brain
45
What are the influences of sex hormones on brain structure
- differences in the distribution of estrogen and androgen receptors during development could affect brain structure
- there are sexually dimorphic regions of the brain in the prefrontal cortex, the paralimbic cortex and the posterior parietal cortex
46
What are the sex differences in brain volume relative to cerebral size
Women
- prefrontal and medial paralimbic regions brain volume significantly higher in women
- estrogen receptors during development
Men
- larger relative volumes in the medial and orbital frontal cortex and the angular gyrus
- androgen receptors during development
47
Sex differences in concentration of gray matter
- males have uniform concentration of gray matter but females have some areas of high and low concentration
48
What are the symmetrical differences between sexes
- women brain more symmetrical than mens
- the asymmetry of the planum temporal and sylvian fissure is more common in men which supports the differences associated with language related structures
- women have more inter-hemispheric connections
49
Can you differentiate between a male and female brain by looking at them
no
- but by the patterns of connections between brain regions found in resting-state fMRI are reliable predictors
- males show greater connectivity in RH
- females LH
50
How to study brain connections and what are the sex differences in brain connections
- diffusion tensor imaging
| shows females have greater inter-hemispheric connectivity and males have greater intra-hemispheric connectivity (within)
51
What is the role of blobs?
- blobs are critical for the perception of color
| - V1
52
What are interblobs
- interblobs are involved in form and motion perception
| - V1
53
what are thick, thin and pale stripes and where are they found
- V2
- thick stripes: form perception
- thin stripes: color perception
- pale stripes: motion perception
54
What is the pathway for incoming visual information in the occipital lobe?
- V1: the first processing level receiving inputs from the Lateral Geniculate nucleus of the THALAMUS and all other occipital areas
- V2: secondary processing location and also projects onward to major visual areas
- after V2 there are three distinct parallel pathways that emerge en route to the parietal cortex and inferior temporal cortex (Dorsal , ventral and STS)
55
What does the Dorsal Stream do for the visual system
- the dorsal stream participates in the visual guidance of movements and involves connections from V2 to the parietal lobe
- HOW
- guiding movements
56
What does the Ventral Stream do for the visual system
- involved in the recognition of objects and motion perception
- V1 to temporal
- responsible for recognizing / identifying objects
- we are only actually conscious of a small amount of what the brain is actually doing
57
What does the Superior Temporal Sulcus do for the occipital lobe (STS)
- involved in processing biological movements such as face perception, walking
- may be uniquely human
- was only found in 2018
58
What is the "what" pathway and what is the How " pathway
- dorsal stream is the how pathway (guides movement) ventral stream is the what pathway (object recognition).
- was concluded by Milner and goodale experiments
59
What areas of the brain are active in early blind patients for echolocation
- the calcarine sulcus of the RH
60
What areas of the brain are active in late blind patients for echolocation
- LB shows activity at the apex of the occipital lobes of the RH and LH as well as in the calcarine sulcus of the LH
61
What is echolocation
- blind people have learned to navigate using echolocation by making brief auditory clicks, shaking keys or snapping their fingers.
- when these sounds are echoed off surrounding objects, the blind echolocators can locate and identify objects
62
What happens if there is destruction of the retina or optic nerve In one eye
- they would still see the left visual field and this is called Monocular blindness
(3 and 4 on diagram)
63
What happens is there is a lesion of the medial region of the optic chiasm which severs the crossing of fibres?
This is called bitemporal hemianopia and includes a loss of vision in both temporal fields
(1 and 4 in diagram)
64
What happens with a lesion of the lateral chiasm
- This is called right nasal hemianopia and results in loss of one nasal field of vision.
65
What happens with a complete cut of the optic tract, LGN, or area V1
This is called homonymous hemianopia or blindness of one entire visual field. So if we sever the connection to the left optic tract we would lose all of the right visual field.
66
What happens with damage to V1
you are basically blind. There are a few sneaky ways that info can get to higher levels without travelling through V1.
67
What happens when theres damage to are V3
- affect form perception
| - to completely eliminate form perception you would need a lesion in both V3 and V4
68
What happens with damage to V4
- loss of color perception and a world of grey
- these patients also lose the ability to remember what colors looked liked before the injury and they cant imagine those colose or think about color
69
What happens with damage to V5
- results in loss of vision of motion
| - individuals can see objects when they are at rest but they vanish as soon as the objects move
70
How could you test the different outcomes of V1 +V2 vs V4 damage?
Primates (better colour vision).
71
Which areas are involved in color processing
V1/V2/V4
72
damage in the visual cortex causes what symptoms
- could detect the presence of light but otherwise blind
| - retained ability to imagine colors
73
What do small occipital lobe lesions often produce?
scotoma
74
What is the primary function of the parietal lobes ?
- to process and integrate somatosensory and visual information
- especially as it applies to movement
75
Who is Constatine Von Economo ? (VE)
- he mapped 4 anterior parietal areas PA, PB, PC, PD
| - he mapped 3 posterior parietal ares PE, PF, PG
76
What is important about where area PG is located?
- may have implication in the STS pathway
- it overlaps with the occipital lobe
- area PG is more expanded in humans
77
What is the Lateral Intraparietal area involved in?
- controls saccadic eye movements
78
What is the Anterior parietal area responsible for?
- visual object-directed grasping
79
What is the posterior reach region involved in ?
- integrate parietal and occipital function to control movements in space
- allows us to direct movements and assign meaning and significance to them
- spatial information
80
What is Stereognosis
- tactile perception
81
What is Asterognosis
- the inability to recognize objects by touch
82
Main function of area PE and is it anterior or posterior?
Guide limb movement by providing information about limb position
-posterior
83
Main function of area PF and is it anterior or posterior?
- has heavy input from the primary somatosensory cortex via PE.
- For Complex guided movement
- posterior
84
Main function of area PG and is it anterior or posterior?
- receives the most complex connections, including visual, skin sensations, proprioceptive (internal stimuli), auditory, vestibular, oculomotor, and cingulate (motivational)
- Involved in spatially guided behaviours, especially those involving visual and tactile info.
- posterior
85
(ANTERIOR) Damage to the postcentral gyrus and adjacent posterior cortex results in what
- how do we test this
- somatosensory symptoms
- difficulty with somatosensory thresholds and deficits in stereognosis
- Patients have abnormally high sensory thresholds (hot/cold press), impaired position sense (elevator) and deficits in stereognosis (tactile perception).
- Afferent Paresis : a loss of kinesthetic feedback, makes finger movements clumsy
- 2-point discrimination task
86
(ANTERIOR PARIETAL DAMAGE) What is asterognosis and how do we test this
- inability to recognizes an object by touch
87
(ANTERIOR PARIETAL DAMAGE) What are the two ways to test asterognosis
TACTILE PERCEPTION TEST
patients are blind folded and objects are placed in either
A) their palm
B) told to handle shapes
88
(ANTERIOR PARIETAL DAMAGE) What is Simultaneous Extinction
the inability to detect a sensory event when paired with another identical sensory event
- damage to RH, lose sight in LVF (if objects are identical)
- damage most common in PE and PF (if objects are not identical)
89
(ANTERIOR PARIETAL DAMAGE) How to test simultaneous Extinction
only can be done through a specific procedure
- presenting two tactile stimuli simultaneously to the same or different body parts. The objective is to uncover those situations in both stimuli.
90
(ANTERIOR PARIETAL DAMAGE)(What is Numb Touch
Who reported it
Where was the damage in the brain
What are the symptoms
- often called blind touch or numb touch
- Jacques Pillard in 1983
- This woman had Damage to PE/PF in left hemisphere
- resulting in complete anesthesia of the right side to the point that patients could be cut or burned without knowing.
- However, if you touched her right arm or hand, she could point to the area with her left hand, even though she said you didn’t touch her.
- This is the only reported case of numb touch.
91
(ANTERIOR PARIETAL DAMAGE) What is Somatosensory Agnosias
- Asomatognosia is a condition where the patient loses knowledge about their own body or condition. It is almost an unbelievable condition until you see it.
- usually affects one side and more commonly the left side
92
(POSTERIOR PARIETAL DAMAGE)
Balint Syndrome
What are the three weird symptoms?
- in 1909 Rezso Balint described a patient whose bilateral parietal lesion was associated with peculiar visual symptoms.
- oculomotor apraxia (paralysis of gaze)
- simultagnosia
- optical ataxia
93
(POSTERIOR PARIETAL DAMAGE) What is oculomotor apraxia
- paralysis of gaze.
- 35-40 degree gaze
- difficulty with peripheral information and have to move head to see things
- will only see things in their gaze and miss everything else
94
(POSTERIOR PARIETAL DAMAGE) What is Simultagnosia
-When attention was directed toward an object, missed other stimuli. Slightly different from simultaneous extinction.
95
(POSTERIOR PARIETAL DAMAGE) What is Optic Ataxia
- visually guided movements were impaired.
- Optic ataxia by itself can emerge from unilateral or bilateral lesions, but the combination of symptoms in Balints syndrome must have damage to both hemispheres.
96
(POSTERIOR PARIETAL DAMAGE) What is contralateral neglect
- A perceptual disorder that results from RIGHT parietal lobe lesions.
- Have no visual field deficits.
- Completely neglect or ignore the left side of the body and their world.
- Generally lack accurate spatial locations and exhibit topographical disability.
- The neglect occurs in the visual, auditory and somatosensory world
97
(POSTERIOR PARIETAL DAMAGE) What areas does the patient need damage in, in order to demonstrate neglect only on the right
- intraparietal sulcus and angular gyrus
98
What are symptoms of Right parietal lesions
- deficits In object recognition
| - drawing deficits
99
(POSTERIOR PARIETAL DAMAGE) What is Gerstmanns Syndrome and its 4 symptoms
- damage around area PG in left parietal lobe
- finger agnosia
- L/R confusion
- Acalculia
- Agraphia (inability to write)
100
What is Ideomotor Apraxia associated with
- L hemisphere lesions
| - R hemisphere lesions dont
101
What is constructional Apraxia
visuomotor disorder in which spatial organization is disrupted
- comes from damage to posterior parietal area
102
How to test somatosensory thresholds
2 point discrimination task
103
how to test tactile form recognition
- manipulate blocks blindfolded
| - shape manipulate likely involved ares PE and PF
104
How to test contralateral neglect
Subjects with contralateral neglect shift the horizontal line more to the right and skip the examples on the left side of the page
105
how to test visual perception
draw the remainder of a incomplete picture
| - damage to R temporoparietal junction
106
How to test spatial relation
pictures of body parts presented in different orientations and identify them as L or R
- L parietal or L frontal lobe damage
107
How to test language
- token test
| - damage to PG in L hemisphere
108
How to test apraxia
Kimura box test
109
What is the role of the Superior Temporal Sulcus in the temporal lobe
- Responsible for biological motion and theory of mind, it separates the superior and middle temporal gyrus
- The STS is a multimodal and polymodal cortex, which in involved in receiving input from the auditory, visual and somatic regions
- Theory of mind: the capacity to understand other people by ascribing mental states
110
How is visual processing accomplished in the temporal lobes
The temporal lobe's role in visual processing is not genetically determined they can teach it, which allows the visual system to adapt to different demands
- FFA and PPA
- Humans prefer to look at other faces more than any other stimuli
111
Haxby and colleagues 2000-looked at the core visual areas in the occipitotemporal part of the ventral stream and found what
- Key take away is that facial analysis is unlike other visual stimuli.
- The face pathway is surprisingly excessive and is located in an area that is difficult to damage
- Prosopagnosia: the inability to recognize faces
- Facial processing is ASYMMETRICAL, this processing is specialized to the right hemisphere.
112
What is the split face test
- a test that researchers used to see that facial processing is ASYMMETRICAL, in the RIGHT HEMISPHERE. The split face test helps researchers see this asymmetry in control patients
113
In split face tests which picture will participants choose
- Participants preferentially select C (or left side of face mirror image) because processing is in the right hemisphere
- Patients with injury to their RIGHT temporal regions cannot match either side of the face in either presentations (don’t notice it)
114
Why do people say " i dont actually look like that" when they see themselves In photos
If you take your own picture and do this you will select B, but your friends will select C
Because... when you look at yourself in the mirror the RIGHT side of you face is reflected to your left visual field and then processed by your right hemisphere
This is why people always say “I don’t actually look like that” when they see themselves in pics.
The more asymmetrical your face us, the more unflattering you perceive yourself because the pics are opposite to your mirror image perceptions
115
Speech differs from other auditory inputs in three ways
Formants: speech sounds come from 3 restricted ranges of frequencies called formants
Vowel sounds are in a constant frequency band but consonants show rapid changes in frequency, syllables differ in both onset frequency and duration
Context Specific: the same speech sounds may vary from context to context but they are perceived the same way (cat and curse, both are C but sounds different and used differently
The major difficulty in learning a new language comes from having to train your temporal lobe to categorize all of the sound
Speed: speech sounds change rapidly in relation to one another and the order of the sounds is very important for understanding
Normal speech- 8-10 segments per second
We can understand 30 segments per second
Non speech noises we can only understand 5 per second
Music is generally slower which is why kids learn language so well from song like “the wheels on the bus go round and round”. We have slowed down the word processing
116
What lobe is speech processed in for both comprehension and movements
Speech is processed in the frontal lobe for both comprehension and movements using the dorsal pathway from the STS to frontal area 44
117
Key difference between music and language
Language is fast and requires fast analysis of individual elements
Music and slower and relies on discrimination between small frequency differences
118
Why is music fundamentally different from language
- Music is fundamentally different from language because music relies on the relationship between auditory elements rather than individual elements
- We know that the brain is primed for music and begins prenatally
119
What makes musical information different
Loudness : the magnitude of the sensation, this is judged by the person and is completely subjective
Females detect things at lower volumes
Timbre: the distinct character of a sounds, the quality that distinguishes it from all other sounds of a familiar pitch and loudness
Example: if a piano and a trombone both play the same note, you can tell that they are different
Pitch: refers to the position of a sound in a musical scale, this is also subjective
Pitch is clearly related to frequency (the vibration of the sound)
Pitches are compared as higher or lower
This is a function of the RIGHT primary auditory cortex
Sound waves themselves to not have a pitch, it takes a human brain to map the internal quality of pitch
Timing:
Melody (RIGHT)
Rhythm (LEFT)
120
What is Herschls gyrus involved in
music
it is larger in the LEFT for fundamental frequency
larger in Right for spectral pitch
121
LEFT TEMPORAL LOBE DAMAGE
- Deficits in verbal memory
- Deficit in processing speech sounds
- Difficulties keeping up the with speed of language (complain people are talking to fast)
- Recognition of language
122
RIGHT TEMPORAL LOBE DAMAGE
- Deficits in non-verbal memory (face)
- Deficits in processing aspects of music and melodies
- Deficits in facial recognition and expression
- Cant discriminate complex frequency patterns
- Recognition of music and sound localization
123
What are symptoms associated with temporal lobe damage
- Disturbances of Auditory sensation and perception
- Disorders of music perception
- Disorders of visual perception
- Stimulus selection
- Categorization and organization
- Using contextual information
- Memory deficits
- Affect and personality
- Sexual behaviour
