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Chapter 17 Flashcards

1
Q

disconnection

A

the cutting or resetting cerebral connection

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2
Q

Disconnection syndrome

A

the ensuing behavioral effects of disconnection

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3
Q

Intact Monkey - anatomically intact

A
  • hemispheres connected by commissures including…
  • optic chiasm - where two hemiretinas intersect
  • corpus callosum - bundle of fibers that interconnect the two hemispheres
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4
Q

tame monkey

A

commissures disconnected, left amygdala removed

  • If the objects were presented to the eye ipsilateral to the hemisphere with the ablated amygdala, the animal appeared tame even if the objects were typically frightening to monkeys.
  • when the right eye is covered, and the left amygdala removed, visual info is unavailable to motor system
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5
Q

wild monkey

A

commissures disconnected, left amygdala removed

  • If the objects were presented to the eye ipsilateral to the intact amygdala, the animal made its usual specie’s typical responses to threats and appeared wild.
  • left eye covered, the circuit in the right hemi for activating species typical behavior is intact.
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6
Q

disconnection monkey experiment results

+ steps

A
  • for an animal to display species’s typical responses to a visual stimulus, information must project from the eye to the visual cortex, passing through the temporal lobes to the amygdala and from the amygdala then to the brain stem and frontal cortex
    • these connections activate respectively the autonomic responses, movements and facial expressions.
  • If that hemisphere contains an intact amygdala, the circuit for activating specie’s typical behavior is complete and behavior would be typical.
  • If the amygdala in the hemisphere is not intact, visual information will be disconnected from modal systems and can not elicit specie’s typical behavior.
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7
Q

three major types of neural fiber pathways connecting to neocortex:

A
  1. association pathways
  2. projection pathways
  3. commissural pathways
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8
Q

association pathways

A
  1. made of long fiber bundles that connect distant neocortical areas
  2. short, subcortical, U-shaped fibers that connect adjacent neocortical areas
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9
Q

projection pathways

A
  • include ascending fibers from lower brain centers up to the neocortex
  • ex: projections from the thalamus, and descending fibers from neocortex to brainstem and spinal cord
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10
Q

commissural pathways

A
  • connect the two hemispheres
  • include principally: corpus callosum, anterior commissure, and hippocampal commissures
  • among areas that do receive interhemispheric connections, the density of projections is not homogeneous
  • Cortical areas that represent the body’s midline, including the central meridian of the visual field, auditory fields, and the track of the body on the somatosensory and motor cortex, have the densest connections
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11
Q

commissural connection in primary visual cortex (V1)

A
  • no interhemispheric connections, except for that part representing the midline of the visual world (visual meridian)
  • V1 represents the visual world topographically, and there is no need for one half of the representation to be connected to the other
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12
Q

commissural connections in motor and sensory areas

A
  • motor and sensory areas for distal parts of the limbs, mainly hands and feet, lack commissural connections
  • bc essential function is to work independently of one another, it could be argued that the connections are not necessary
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13
Q

callosal connections (3)

A
  1. most callosal projections connect to homotopic areas, presumably to meet the two areas together functionally
  2. projection zones within a hemisphere also connect to homotopic zones in the contralateral hemisphere
    • ex: area V1 is connected to area V2, not only within a hemisphere, but also across hemispheres, because area V1 in one hemisphere also sends connection to area V2 in the opposite hemisphere
  3. a group of projections has a diffuse terminal distribution
    • possibly to alert appropriate zone in one hemisphere that the other is active
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14
Q

homotopic areas

A

identical points in the two cerebral hemispheres that are related to the body’s midline

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15
Q
A
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16
Q

genu

A
  • anterior part of corpus callosum
  • contains the fibers projecting from the prefrontal cortex
  • Fibers through the body of the corpus callosum, proceeding from front to the back, project from the premotor, motor, somatosensory, and posterior parietal cortices
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17
Q

splenium

A

Fibers in the posterior callosum, or splenium, project from the superior temporal, inferior temporal, and visual cortices.

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18
Q

anterior commissure

A

much smaller than the corpus callosum and connects parts of the anterior temporal lobe, amygdala, and the paralimbic cortex of the temporal lobe surrounding the amygdala

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19
Q

humans born without corpus callosum

anterior commissure

A

the anterior commissure is greatly enlarged to connect far greater regions of the neocortex

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20
Q

connectome studies

goals

A
  1. demonstrate that large scale neural networks underlie complex cognitive operations
  2. seek to unravel neural network architecture and how networks relate to cerebral functions
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21
Q

Diffusion Tensor Imaging and DTI tractography

A

they can be mathematically described as comprising sets of nodes, neuronal elements and edges

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22
Q

graph theory

A
  • nodes (neuronal elements) interconnect with related nodes and clustering to functional modules
  • Individual modules maintain mutual nodal connections, but form few connections called hubs, to other modules
  • Mathematical analysis have identified a specific and especially densely connected set of hub regions that require disproportionately high metabolic activity and are believed to factor in efficient communication and functional integration across the brain.
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23
Q

connector hub

A

nodes that connect with connector hubs in other modules

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24
Q

provincial hub

A

nodes that connect primarily to similar nodes in the same module

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25
Q

connectivity of cortical hubs in human brain

A
  • Each hub participates in several dynamic brain networks as defined by fMRI and Magnetoencephalography recordings, MEG recordings including the default and salience networks
  • Cortical hubs emerged relatively early in brain development but continue to increase their functional interactions into adolescence.
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26
Q

importance of severed connections as an underlying factor in the effects of cerebral damage

Hugo Liepmann
If a patient was given a verbal command to use the left hand in a particular way

A

some apraxias might result from disconnections

  • If a patient was given a verbal command to use the left hand in a particular way, only the verbal left hemisphere will understand the command
    • implies that to move the left hand, a signal will then have to travel from the left hemisphere through the corpus callosum to the right hemispheric region that controls movement of the left hand
  • interrupting the part of the corpus callosum that carries the command from the left hemisphere to the right will disconnect the right hemisphere’s motor region from the command
  • apraxia will occur in the absence of the weakness or incoordination of the left hand
    • will develop in the presence of a lesion of the right hemisphere motor cortex, which controls the actual movement of the left hand.
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27
Q

Behavioral effects of severing corpus callosum in cats

(Myers and Sperry)

A
  • if sensory information was allowed separate access to each hemisphere, each hemisphere could be shown to have its own independent perceptual, learning, and memory processes
  • corpus callosum is important
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28
Q

why disconnection of neocortex is easy

A
  1. the primary sensory areas have no direct connections among one another
  2. even in higher-order sensory zones, only few direct connections exist among sensory systems
  3. the hemispheres are in large part symmetrical and are connected by only a few projection systems
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29
Q

hemispheres may become completely separated under three conditions:

A
  1. cut as therapy for epilepsy - commissurotomy
  2. callosal agenisis
  3. animal research
    • disconnections are performed to trace functional systems, to model human symptoms, and to answer basic questions about interhemispheric development
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30
Q

commissurotomy

recovery

A
  • surgical several of cerebral commissures
  • elective treatment for intractable epilepsy
    • when medication is ineffective
  • each hemisphere retains fibers that allow it to see only the opposite side of the visual world
    • each hemisphere predominantly receives information from the opposite side of the body and controls movement on the opposite side of the body
    • isolates speech in persons with lateralized speech
      • the dominant hemisphere, usually the left, is able to speak, and the non-dominant hemisphere is not
  • “typical” behavior recovers within two years despite independent functioning of hemispheres
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31
Q

split brain patients

A
  • their scores on standardized tests are normal
  • patient’s everyday behavior appears similar to that of typical unified people
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32
Q

specific tests on split brain patients

A
  • specific tests, such as those Sperry and his coworkers obtain with their split-brain patients in 1974, can still show differences between the functioning of split-brain patients and that of people with intact cerebral connections
    • usual testing procedures include presenting stimuli only to one hemisphere and then testing each hemisphere for what transpired
    • ex: split-brain patient who is asked to touch an out-of-view object with one hand, and then find a similar object with the other hand, is unable to match the objects
      • each hemisphere can be shown to have its own sensations, percepts, thoughts, and memories, that are not accessible to the other hemisphere
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33
Q

callosal agenesis

impairments

A

congenitally reduced or absent interhemispheric connections

  • can perform inter hemispheric comparisons of visual and tactile info
    • patients have enhanced conduction in the remaining commissure (ex: vision)
    • developed enhanced ability to use their few uncrossed projections (ex: tactile info)
  • impaired general intelligence, expressive and receptive language, visual and spatial reasoning, memory, motor skills, etc
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34
Q

sensory disconnection

olfaction

A

connections are not crossed

  • input from left nostril goes straight back into left hemi, same with right
  • fibers travel through the anterior commissure join the olfactory regions in each hemisphere
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35
Q

sensory disconnnection - olfaction

case

A
  • case: patient whose anterior commissure is severed - cannot name odors presented to the right nostril because the speaking left hemisphere is disconnected from the information
  • rt hemi has the info but no control of speech
  • olfactory function still intact but because the patient can use the left hand to pick out an object such as an orange that corresponds to the odor, smell
    • no connection with speech is necessary because the right hemisphere both contains the olfactory information and controls the left hand
  • if requested to use the right hand the patient will be unable to pick out the object because the left hemisphere which controls the right hand is disconnected
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36
Q

sensory disconnection

vision

A

information flashed to one visual field travels selectively to the contralateral hemisphere

  • verbal material including words is perceived more accurately when presented to the right visual field
    • prob bc the input travels to left “speaking” hemi
  • visual spacial input such as a map produces a left visual field superiority because the right hemisphere appears to be superior to the left in analyzing spacial information
  • visual field superiority observe the neuro-typical controls is relative
    • visuospatial input - left field superiority
    • relative effects occur because either hemisphere potentially has access to input to the opposite hemisphere through the corpus callosum which connects the visual area
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37
Q

sensory disconnection

vision

words presented to the left visual field

A

words presented to the left visual field and hence in right hemisphere are sometimes perceived, although not as accurately or consistently as when presented to the right visual field

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38
Q

sensory disconnection

vision

words presented to right visual field

A

verbal material perceived more accurately when presented to rt visual field, bc the input travels to the left, speaking hemisphere

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39
Q

if obj presented to left visual field

commissurotomy patient

A
  • commissurotomy pt unable to read it or answer qs about it verbally (but right visual field no difficulties)
  • commissurotomy pt will be unable to name it and will appear agnosic and aphasic
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40
Q

if obj presented to right visual field

commissurotomy pt

A

commissurotomy pt

obj will be correctly named

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41
Q

sensory disconnection

vision

split brain

A

the split brain pt is aphasic, alexic, and agnosic if verbal material or an obj requiring verbal response to presented visually only to rt hemi, but intact if material is presented to left hemi

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42
Q

sensory disconntection

somatosensory functions

A
  • if the two hemispheres are disconnected the somatosensory functions of the left and right parts of the body become independent
  • ex: if some object is placed in the left hand of a blindfolded callosal patient who is then asked to choose the presented object from an array of objects the left hand can pick out the object but the right hand cannot
    • if an object is placed in a blindfolded patient’s right hand the patient can name it but cannot do so if the object is placed in the left hand because the sensory input is disconnected from the left speech hemisphere
    • one hand has no way of knowing what the other hand is doing inn the absence of input coming from opposite hemisphere
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43
Q

normally

if object placed in left hand

if person is blind folded and right hand is molded into particular shape

A
  • if obj placed in lt hand - can be named because tactile info projects to right hemi, crosses to left, and has access to speech zones
  • if a person is blindfolded an rt hand is molded to form a particular shape, the left hand is able to copy the shape
44
Q

sensory disconnection

audition

A

both crossed and uncrossed connections

  • words played in left ear can travel directly to the left hemisphere or can go to the right hemisphere and then to the left through the corpus callosum
    • bilateral anatomical arrangement appears to reduce the effects of these connections
45
Q

dichotic listening task

A
  • input from the left ear is thoroughly suppressed
  • patient reports only those words played to the right ear
    • digits or words played to the right ear are reported but no input to the left ear is reported
  • surprising because words played to the left ear even under these conditions will be expected to attain some direct access to the left hemisphere. But this direct access does not appear to exist when the hemispheres are disconnected.
46
Q

partial disconnection

Posterior part of corpus callosum is intact

A
  • combine markedly milder effects than those of complete commissurotomy with the same therapeutic benefits
  • patients with partial disconnection are significantly better at motor tasks
47
Q

partial disconnection

splenium

A

subserves visual transfer

48
Q

partial disconnection

region just in front of splenium

A

affects somatosensory transfer

49
Q

The term “disconnection syndrome” is used to describe the behavioral effects of …

a. the disruption of communication between the brainstem and cerebrum
b. psychiatric disorders characterized by out-of-body experiences
c. the destruction of one or more cortical regions contributing to a neural network
d. an interruption of communication between two cerebral regions

A

d. an interruption of communication between two cerebral regions

50
Q

The MOST posterior portion of the corpus callosum is called the…

51
Q

Commissurotomy is performed in humans primarily as a treatment for …

52
Q

The condition that results from severing the anterior commissure is called _______.

53
Q

The only sensory system whose afferent fibers do NOT cross is …

A

olfactory system

54
Q

Functionally, the visual system is entirely crossed, such that stimuli in the left-visual field are initially processed by the right-visual cortical areas and vice versa. Which of the following systems is MOST similar to vision in this regard?

A

somatosensory

55
Q

On which of the following tasks would you expect to see the LEAST impairment following hemispheric disconnection?

a. tactile apperception
b. chimeric face perception
c. puzzle assembly
d. dichotic listening

A

d. dichotic listening

56
Q

_____ is the name of the aphasic syndrome that is the result of a disconnection between the anterior and posterior speech zones.

A

conduction aphasia

57
Q

anosomic

A

lacking sense of smell

58
Q

conduction aphasia

A

speech sounds and movements are retained, but speech is impaired because it cannot be conducted form one region to the other

59
Q

the cutting or resetting cerebral connection

A

disconnection

60
Q

the ensuing behavioral effects of disconnection

A

Disconnection syndrome

61
Q
  • hemispheres connected by commissures including…
  • optic chiasm - where two hemiretinas intersect
  • corpus callosum - bundle of fibers that interconnect the two hemispheres
A

Intact Monkey - anatomically intact

62
Q

commissures disconnected, left amygdala removed

  • If the objects were presented to the eye ipsilateral to the hemisphere with the ablated amygdala, the animal appeared tame even if the objects were typically frightening to monkeys.
  • when the right eye is covered, and the left amygdala removed, visual info is unavailable to motor system
A

tame monkey

63
Q

commissures disconnected, left amygdala removed

  • If the objects were presented to the eye ipsilateral to the intact amygdala, the animal made its usual specie’s typical responses to threats and appeared wild.
  • left eye covered, the circuit in the right hemi for activating species typical behavior is intact.
A

wild monkey

64
Q
  1. association pathways
  2. projection pathways
  3. commissural pathways
A

three major types of neural fiber pathways connecting to neocortex:

65
Q
  1. made of long fiber bundles that connect distant neocortical areas
  2. short, subcortical, U-shaped fibers that connect adjacent neocortical areas
A

association pathways

66
Q
  • include ascending fibers from lower brain centers up to the neocortex
  • ex: projections from the thalamus, and descending fibers from neocortex to brainstem and spinal cord
A

projection pathways

67
Q
  • connect the two hemispheres
  • include principally: corpus callosum, anterior commissure, and hippocampal commissures
  • among areas that do receive interhemispheric connections, the density of projections is not homogeneous
  • Cortical areas that represent the body’s midline, including the central meridian of the visual field, auditory fields, and the track of the body on the somatosensory and motor cortex, have the densest connections
A

commissural pathways

68
Q
  • no interhemispheric connections, except for that part representing the midline of the visual world (visual meridian)
  • V1 represents the visual world topographically, and there is no need for one half of the representation to be connected to the other
A

commissural connection in primary visual cortex (V1)

69
Q
  • motor and sensory areas for distal parts of the limbs, mainly hands and feet, lack commissural connections
  • bc essential function is to work independently of one another, it could be argued that the connections are not necessary
A

commissural connections in motor and sensory areas

70
Q
  1. most callosal projections connect to homotopic areas, presumably to meet the two areas together functionally
  2. projection zones within a hemisphere also connect to homotopic zones in the contralateral hemisphere
    • ex: area V1 is connected to area V2, not only within a hemisphere, but also across hemispheres, because area V1 in one hemisphere also sends connection to area V2 in the opposite hemisphere
  3. a group of projections has a diffuse terminal distribution
    • possibly to alert appropriate zone in one hemisphere that the other is active
A

callosal connections

71
Q

identical points in the two cerebral hemispheres that are related to the body’s midline

A

homotopic areas

72
Q
  • anterior part of corpus callosum
  • contains the fibers projecting from the prefrontal cortex
  • Fibers through the body of the corpus callosum, proceeding from front to the back, project from the premotor, motor, somatosensory, and posterior parietal cortices
73
Q

Fibers project from the superior temporal, inferior temporal, and visual cortices.

74
Q

much smaller than the corpus callosum and connects parts of the anterior temporal lobe, amygdala, and the paralimbic cortex of the temporal lobe surrounding the amygdala

A

anterior commissure

75
Q

the anterior commissure is greatly enlarged to connect far greater regions of the neocortex

A

humans born without corpus callosum

anterior commissure

76
Q
  1. demonstrate that large scale neural networks underlie complex cognitive operations
  2. seek to unravel neural network architecture and how networks relate to cerebral functions
A

connectome studies

goals

77
Q

they can be mathematically described as comprising sets of nodes, neuronal elements and edges

A

Diffusion Tensor Imaging and DTI tractography

78
Q
  • nodes (neuronal elements) interconnect with related nodes and clustering to functional modules
  • Individual modules maintain mutual nodal connections, but form few connections called hubs, to other modules
  • Mathematical analysis have identified a specific and especially densely connected set of hub regions that require disproportionately high metabolic activity and are believed to factor in efficient communication and functional integration across the brain.
A

graph theory

79
Q

nodes that connect with connector hubs in other modules

A

connector hub

80
Q

nodes that connect primarily to similar nodes in the same module

A

provincial hub

81
Q
  • Each hub participates in several dynamic brain networks as defined by fMRI and Magnetoencephalography recordings, MEG recordings including the default and salience networks
  • Cortical hubs emerged relatively early in brain development but continue to increase their functional interactions into adolescence.
A

connectivity of cortical hubs in human brain

82
Q

some apraxias might result from disconnections

  • If a patient was given a verbal command to use the left hand in a particular way, only the verbal left hemisphere will understand the command
  • implies that to move the left hand, a signal will then have to travel from the left hemisphere through the corpus callosum to the right hemispheric region that controls movement of the left hand
  • interrupting the part of the corpus callosum that carries the command from the left hemisphere to the right will disconnect the right hemisphere’s motor region from the command
  • apraxia will occur in the absence of the weakness or incoordination of the left hand
    • will develop in the presence of a lesion of the right hemisphere motor cortex, which controls the actual movement of the left hand.
A

importance of severed connections as an underlying factor in the effects of cerebral damage

Hugo Liepmann

83
Q
  • if sensory information was allowed separate access to each hemisphere, each hemisphere could be shown to have its own independent perceptual, learning, and memory processes
  • corpus callosum is important
A

Behavioral effects of severing corpus callosum in cats

(Myers and Sperry)

84
Q
  1. the primary sensory areas have no direct connections among one another
  2. even in higher-order sensory zones, only few direct connections exist among sensory systems
  3. the hemispheres are in large part symmetrical and are connected by only a few projection systems
A

why disconnection of neocortex is easy

85
Q
  1. cut as therapy for epilepsy - commissurotomy
  2. callosal agenisis
  3. animal research
    • disconnections are performed to trace functional systems, to model human symptoms, and to answer basic questions about interhemispheric development
A

hemispheres may become completely separated under three conditions:

86
Q
  • surgical several of cerebral commissures
  • elective treatment for intractable epilepsy
    • when medication is ineffective
  • each hemisphere retains fibers that allow it to see only the opposite side of the visual world
    • each hemisphere predominantly receives information from the opposite side of the body and controls movement on the opposite side of the body
    • isolates speech in persons with lateralized speech
      • the dominant hemisphere, usually the left, is able to speak, and the non-dominant hemisphere is not
  • “typical” behavior recovers within two years despite independent functioning of hemispheres
A

commissurotomy

87
Q
  • their scores on standardized tests are normal
  • patient’s everyday behavior appears similar to that of typical unified people
A

split brain patients

88
Q
  • specific tests, such as those Sperry and his coworkers obtain with their split-brain patients in 1974, can still show differences between the functioning of split-brain patients and that of people with intact cerebral connections
    • usual testing procedures include presenting stimuli only to one hemisphere and then testing each hemisphere for what transpired
    • ex: split-brain patient who is asked to touch an out-of-view object with one hand, and then find a similar object with the other hand, is unable to match the objects
      • each hemisphere can be shown to have its own sensations, percepts, thoughts, and memories, that are not accessible to the other hemisphere
A

specific tests on split brain patients

89
Q

congenitally reduced or absent interhemispheric connections

  • can perform inter hemispheric comparisons of visual and tactile info
    • patients have enhanced conduction in the remaining commissure (ex: vision)
    • developed enhanced ability to use their few uncrossed projections (ex: tactile info)
  • impaired general intelligence, expressive and receptive language, visual and spatial reasoning, memory, motor skills, etc
A

callosal agenesis

90
Q

connections are not crossed

  • input from left goes straight back into left hemi, same with right
A

sensory disconnection

olfaction

91
Q
  • case: patient whose anterior commissure is severed - cannot name odors presented to the right nostril because the speaking left hemisphere is disconnected from the information
  • rt hemi has the info but no control of speech
  • olfactory function still intact but because the patient can use the left hand to pick out an object such as an orange that corresponds to the odor, smell
    • no connection with speech is necessary because the right hemisphere both contains the olfactory information and controls the left hand
  • if requested to use the right hand the patient will be unable to pick out the object because the left hemisphere which controls the right hand is disconnected
A

sensory disconnnection - olfaction

case

92
Q

information flashed to one visual field travels selectively to the contralateral hemisphere

  • verbal material including words is perceived more accurately when presented to the right visual field
    • prob bc the input travels to left “speaking” hemi
  • visual spacial input such as a map produces a left visual field superiority because the right hemisphere appears to be superior to the left in analyzing spacial information
  • visual field superiority observe the neuro-typical controls is relative
    • visuospatial input - left field superiority
    • relative effects occur because either hemisphere potentially has access to input to the opposite hemisphere through the corpus callosum which connects the visual area
A

sensory disconnection

vision

93
Q

words presented to the __ visual field are sometimes perceived, although not as accurately or consistently

A

sensory disconnection

vision

words presented to the left visual field

94
Q

verbal material perceived more accurately when presented to ___ visual field, bc the input travels to the ___

A

sensory disconnection

vision

words presented to right visual field

right, left

95
Q
  • commissurotomy pt unable to read it or answer qs about it verbally (but right visual field no difficulties)
  • commissurotomy pt will be unable to name it and will appear agnosic and aphasic
A

if obj presented to left visual field

commissurotomy patient

96
Q

commissurotomy pt

obj will be correctly named

A

if obj presented to right visual field

commissurotomy pt

97
Q

the split brain pt is aphasic, alexic, and agnosic if verbal material or an obj requiring verbal response to presented visually only to rt hemi, but intact if material is presented to left hemi

A

sensory disconnection

vision

split brain

98
Q
  • if the two hemispheres are disconnected the somatosensory functions of the left and right parts of the body become independent
  • ex: if some object is placed in the left hand of a blindfolded callosal patient who is then asked to choose the presented object from an array of objects the left hand can pick out the object but the right hand cannot
    • if an object is placed in a blindfolded patient’s right hand the patient can name it but cannot do so if the object is placed in the left hand because the sensory input is disconnected from the left speech hemisphere
    • one hand has no way of knowing what the other hand is doing inn the absence of input coming from opposite hemisphere
A

sensory disconntection

somatosensory functions

99
Q

both crossed and uncrossed connections

  • words played in left ear can travel directly to the left hemisphere or can go to the right hemisphere and then to the left through the corpus callosum
    • bilateral anatomical arrangement appears to reduce the effects of these connections
A

sensory disconnection

audition

100
Q
  • input from the left ear is thoroughly suppressed
  • patient reports only those words played to the right ear
    • digits or words played to the right ear are reported but no input to the left ear is reported
  • surprising because words played to the left ear even under these conditions will be expected to attain some direct access to the left hemisphere. But this direct access does not appear to exist when the hemispheres are disconnected.
A

dichotic listening task

101
Q

patients are significantly better at motor tasks

A

partial disconnection

Posterior part of corpus callosum is intact

102
Q

subserves visual transfer

A

partial disconnection

splenium

103
Q

affects somatosensory transfer

A

partial disconnection

region just in front of splenium

104
Q

lacking sense of smell

105
Q

speech sounds and movements are retained, but speech is impaired because it cannot be conducted form one region to the other

A

conduction aphasia

Neuropsych (15 decks)

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