Chapter 3 - Anatomy Of The Nervous System Flashcards
1
Q
Brain-body orientation is the “______ ______”
A
human face
2
Q
Spatial orientation is the “______ ______ ______”
A
Other body parts/body orientation
3
Q
Anatomical orientation is the “______ __ ______” through the brain from perspective of the viewer
A
Direction of section
4
Q
“_______” is towards the back
A
Dorsal
5
Q
“_______” is towards the stomach
A
Ventral
6
Q
“_______” is towards the front
A
Anterior
7
Q
“________” is towards the rear
A
Posterior
8
Q
“_______” is above another structure
A
Superior
9
Q
“________” is below another structure
A
Inferior
10
Q
“_______” is towards the side
A
Lateral
11
Q
“_______” is towards the middle
A
Medial
12
Q
Nerve does “______” equal neuron
A
NOT
Neuron: single neural cell
Nerve: bundle of axons running together (only used in PNS)
13
Q
What is a tract?
A
Bundle of axons running together in the CNS
14
Q
What is a nucleus?
A
Group of cell bodies in CNS
15
Q
What is a ganglion?
A
Group of cell bodies in PNS
16
Q
The CNS includes what?
A
Brain
Spinal cord
17
Q
The PNS includes what?
A
Somatic nervous system
Autonomic nervous system
Enteric nervous system
18
Q
The somatic nervous system does what?
A
Transmits sensation, produces movement
Cranial nerves
Spinal nerves
19
Q
The autonomic nervous system does what?
A
Balances internal functions
Sympathetic division (arousing)
Parasympathetic (calming)
20
Q
The enteric nervous system does what?
A
Controls the gut
21
Q
What are the 3 types of neurons?
A
1) motor: commands to muscles/organs
2) sensory: carry info from body —-> brain/spinal cord
3) interneurons: neurons connect one neuron to another in same part of brain/spinal cord
22
Q
Difference b/w efferent and afferent? (Information)
A
Efferent: OUT of the CNS
Afferent: INTO the CNS
23
Q
What are the layers to protecting the brain?
A
Skull
**Dura mater
**Arachnoid membrane
**Pia mater
**= MENINGES
Subarachnoid space (filled w CSF)
24
Q
What does the forebrain control?
A
Highly developed, numerous functions
25
What does the midbrain control?
Reflex actions and voluntary movements
26
What does the hindbrain control?
Vital functions and coordinating movements
27
The cerebral cortex is the “_____ ______” of the frontal lobe
Outer layer
28
The cerebral hemispheres is the “______, _______ _________” dominating brains appearance
Large, wrinkled structures
29
Give the definition of these “surface” features…
Cortex
Gyrus
Sulcus
Fissure
Cortex: outer surface of brain, cell bodies/neurons
Gyrus: each ridge in surface of brain
Sulcus: groove/space b/w 2 gyri
Fissure: large groove/space b/w 2 gyri
30
What are the lateral ventricles?
Winged-shaped cavities
Filled w CSF made by interconnected blood vessels
Interior feature of brain
31
What is CSF?
Cerebrospinal fluid
Suspends the brain, acts as SHOCK absorber
Provides stable environment for function
32
There are “____” pairs of cranial nerves
12
Control sensory and motor functions of the head, neck and face
33
There are “___” pairs of spinal nerves divided into “__” anatomical regions
30
5
Cervical, thoracic, lumbar, sacral and coccygeal
34
What are dermatomes?
Body segments associated with nerve
35
What is the neuronal circuits as a functional unit?
(Ten principles of NS function)
Neuronal circuits: series of neurons that serve a function when ACTIVATED, connected by synapses
1. Monosynaptic: sensory & motor neuron
2. Poly synaptic: at least one interneuron present
36
What is sensory and motor divisions?
(Ten principles of NS function)
Kept SEPERATE throughout the nervous system
Divided in the CORTEX 2 ways:
1. Separate sensory and motor cortical region
2. Entire cortex is organized around this distinction
37
What is hierarchical & parallel organization?
(Ten principles of NS function)
Brain has BOTH of these
Proximity & connection often indicate SHARED/SIMILAR function
38
Why are many circuits crossed?
(Ten principles of NS function)
Because info passes from ONE side of the body to the OTHER
Ex) right motor cortex influences actions on the left side of the body
39
What are localized and distributed functions?
(Ten principles of NS function)
DAMAGE to one area can INTERFERE w/ a particular function
Any one location is RARELY the only thing in involved in that FUNCTION
40
What is brain symmetry & asymmetry?
(Ten principles of NS function)
HEMISPHERES look like mirror images, BUT some DISSIMILAR features exsists
CORTICAL ASYMMETRY is essential for INTREGRATIVE tasks (language/body control)
41
What is hemispheric lateralization?
Handedness
Rootedness
Ocular dominance
Aural dominance
42
What does the right hemisphere control?
Feelings, intuition & humour
Aesthetic & colour
Relationships, rhythm, physical senses & motor skills
***THE LEFT SIDE OF THE BODY
43
What does the left hemisphere control?
Analytical thinking, rules & logic
Structure, mathematics & planning
Speech, language & time
***THE RIGHT SIDE OF THE BODY
44
Left visual field is processed in the “______ __________” of the brain
Right visual field is processed in the “_______ _________” of the brain
Right hemisphere; left hemisphere
45
What is inhibition and excitation in balance?
(Ten principles of NS function)
Juxtaposition in both action and activity
• Making movements and prevents movements
• Excitation (increased neural activity) and inhibition (decreased neural activity)
46
What is the ventral and dorsal visual streams?
(Ten principles of NS function)
Occipital lobe —> dorsal stream —> parietal lobe
Striate cortex (region v1) —> ventral stream —> temporal lobe
47
What is the perceptual world from sensory input?
(Ten principles of NS function)
The nervous system produces movement in a perceptual world the brain CONSTRUCTS
Perception and experiences are SUBJECTIVE
Individual differences in systems, past experience, current state, etc.
48
What is neuroplasticity?
(Ten principles of NS function)
Experience ALTERS the brain’s organization:
- memory and learning
- forgetting due to loss of memory connections
****HOWEVER plasticity CAN be beneficial:
- recovery from brain injuries and diseases
- normal aging
49
How can we go from A —> B?
How can we go from B —> A?
How do we have A —> C —> B?
***DEVELOPMENT OF BRAIN & BEHAVIOUR
1. STRUCTURAL development can relate to emerging BEHAVIOURS
2. BEHAVIOUR development can relate to emerging STRUCTURES
3. Other factors can influence BOTH at once
50
As structures “_______” functions emerge and develop
“_________ _________” that develop quickly exhibit “_________” sooner
Mature; neural structures; functions
51
What is included in the prenatal stage (zygote)?
Day 1: fertilization
Day 2: division
Day 15: embryonic disk ***LOOKS LIKE A FRIED EGG
52
What is included in the prenatal stage (embryo)?
Neural plate:
- 3 weeks after conception
- thickened region of the ectodermal layer that gives rise to the NEURAL TUBE
Neural tube:
- structure in the early stage of the brain development from which the BRAIN and SPINAL CORD develop
53
What is included in the prenatal stage (fetus)?
Occurs around 9-12th week and occurs until 36th week
Forebrain, midbrain, hindbrain, and neural tube (forms spinal cord) developed by 36th week
54
What are the stages of brain development (fetus)?
7 stages
1. Cell birth (neurogenesis; gliogenesis)
2. Neural migration
3. Cell differentiation
4. Neural maturation (dendrite and axon growth)
5. Synaptogenesis (formation of synapses)
6. Cell death and synaptic pruning
7. Myelogenesis (formation of myelin)
55
What are the origins of neural cells (fetus)?
3 types
Progenitor cell: precursor cell derived from a STEM cell
- migrates and produces nondividing cells known as neuroblasts and glioblasts
Neuroblast: gives rise to different types of NEURONS
Glioblast: gives rise to different types of GLIAL cells
56
What is cell migration (fetus)?
Radial glial cells: PATH-MAKING CELLS that a
migrating neuron follows to its destination
Begins shortly after the first neurons are generated
Continues for 6 weeks in the cortex and throughout life in the hippocampus
57
What is cell differentiation (fetus)?
Neuroblasts become SPECIFIC TYPES of neurons
Cell differentiation begins after cells have started to migrate
58
What is neural maturation (fetus)?
2 ways
Mature in two ways:
1. DENDRITIC GROWTH: grow dendrites to provide surface area for synapses with other cells
- arborization (branching): growth of dendritic spines where most synapses occur
2. AXONAL GROWTH: extend axons to appropriate targets to initiate synapse formation
***Takes place AFTER neurons migrate to destination and differentiate into specific types
59
Each hemisphere is divided into 4 lobes, what are these?
1. Frontal (executive function)
2. Parietal (sensory integration)
3. Temporal (auditory, taste, smell, memory)
4. Occipital (visual)
60
Explain the difference between the different views of the brain
1. Dorsal view (looking down, from top)
2. Lateral view (looking from the side)
3. Ventral view (looking from the bottom)
4. Medial view (looking from the inside, sliced down the middle)
61
What is the allocortex VS the neocortex?
Allocortex:
- three-layered and four-layered cortex
- BELOW-SURFACE STRUCTURES
- evolved EARLIER than neocortex
Neocortex:
- six-layered cortex
- outer layer that us VISIBLE when we look at the SURFACE of brain
62
What structures are involved in the limbic system & what does it regulate?
STRUCTURES…
Amygdala
Hippocampus
Cingulate cortex
Thalamus????
———————————
REGULATES…
Emotional/sexual behaviours
Memory
Spatial navigation
63
What does the amygdala do?
Increases electrical activity in its neurons when we are under THREAT
Flight or flight response
Remember events tied to STRONG emotions
SENSORY INPUT received to determine emotional value/intensity of stimulus
64
What does the hippocampus do?
Formation and retrieval of memories (assists DECLARAITIVE memory formation)
65
What does the cingulate cortex (cingulate gyrus) do?
Helps focus ATTENTION & THOUGHTS
Especially on things that are unpleasant to us
66
What structures are involved in the olfactory system?
What is the vomersonal organ (VNO)?
STRUCTURES…
Pyriform cortex
Amygdala
Dorsomedial thalamus
——————————————
Vomeronsal organ (VNO): sensory neurons that detect pheromones
67
What structures are in the basal ganglia and what does it regulate?
STRUCTURES…
Caudate nucleus
Putamen
Globus pallidus
————————————————————-
REGULATES…
VOLUNTARY & UNVOLUNTARY movement
68
What does the thalamus do?
RELAYS incoming sensory through groups of neurons that project to the appropriate REGION in the CORTEX
Actively FILTERS incoming sensory information
69
What does the hypothalamus do?
Regulates the AUTONOMIC and ENDOCRINE systems
Hunger responses, sexual behaviour, temp control and aggression
HOMEOSTASIS
70
What is the reticular formation in the midbrain?
Helps to regulate AWARENESS & ATTENTION (filter)
Regulate SLEEP & WAKEFULNESS (arousal)
***Coordinates several brain areas (imagine visual stimuli ————> diff arrows all going diff directions)
71
What does the hindbrain do?
Regulation of BASIC LIFE functions
Connects PERIPHERAL & CNS
72
What does the medulla do?
Why is damage to the hindbrain typically fatal?
Controls HEART activity & CIRCULATION
Regulates BREATHING
Involved in coordinating SWALLOWING & DIGESTION
—————————————————————————
FATAL DUE TO…
All sensory/motor nerve tracts ascend from the SPINAL CORD & descend from the BRAIN
73
What does the pons do?
RELAY station for SIGNALS b/w higher levels of the nervous system & lower levels
Connects to MUSCLES & GLANDS IN FACE/NECK
74
What does the cerebellum do?
Controls bodily COORDINATION, BALANCE, & MUSCLE TONE (fine motor control)
Sequences of actions
Involved in PROCEDURAL memory (memory of motor skills)
75
What is synaptogenesis (fetus)?
Synaptic development
Schedule:
1. 5th gestational month: SIMPLE synaptic contacts
2. 7th gestational month: synaptic development of DEEP cortical neurons
3. after birth: development increases RAPIDLY during 1st year of life
76
What is cell death & synaptic pruning (fetus)?
Unecessary cells & connections REMOVED due to GENETIC INSTRUCTIONS, experience, hormones etc…
Cortex becomes THINNER in a caudal-rostral (back to front) gradient
DUE to pruning^^^
77
What is myelogenesis (fetus)?
Formation of myelin via glial development
Formation of ASTROCYTES (role in synaptic pruning/plasticity) & OLIGODENDROCYTES (myelin in CNS)
Begins after most neurogenesis is complete and continues throughout life
78
Light coloured zones (on the brain) “_________ ______”
Myelinated last
79
How is neurogenesis studied in the adult brain?
What about in the animal brain?
Most studied region is the hippocampus (found significant neurogenesis in here)
Hippocampus it involved in formation of new memories so this makes sense
————————————————————————-
Most studied region in animals is ONLY in the hippocampus, subventricular zone, hypothalamus, striatum, substantia nigra, neocortex, and amygdala
***THIS IS ALL DEBATED
80
The hypothalamus is a “_________” b/w the endocrine system and the nervous system
Bridge
As it maintains homeostasis
81
What is the endocrine system?
Series of GLANDS throughout the body that release HORMONES
Serves as a secondary control system
Feedback to NS
Tends to be slower
82
Name the 5 main endocrine glands
1. Pituitary: “director” growth hormone
2. Thyroid: metabolic rate
3. Adrenal: salt & carbohydrate
4. Pancreas: sugar metabolism
5. Gonads: sex hormones
83
How does the hypothalamus work to control the endocrine system?
SECRETES hormones
Controls the PITUITARY GLAND via direct nerve stimulation & chemicals
84
How do the pineal glands work to control the endocrine system?
SECRETE melatonin to REGULATE sleep cycles
85
How does the pituitary gland work to control the endocrine system?
SECRETES hormones that affect sexual behaviour, reproduction, circulatory function, hunger * responses to aggression
86
What is the HPA axis?
Hypothalamic- pituitary adrenal axis
Activated in times of stress
How the brain affects the IMMUNE system
87
The two main types of neural tissue are “_________”, which forms the connections among cells, and “_____________” which collects and processes incoming (afferent) sensory or outgoing (efferent) information
White; gray
88
Bundles of nerve fibres (axons) in the brain and spinal cord are called “__________”. Outside the brain and spinal cord these bundles are called “____________”.
Tracts; nerves
89
What is the diencephalon also called?
“Between brain”
Two structures are the hypothalamus and thalamus
90
What diseases interfere with the basal ganglia?
Parkinson’s disease (severe tremors, muscular rigidity, reduced involuntary movement)
Tourette syndrome (motor tics, involuntary vocalizations)
***DISORDER OF CONTROLLING MOVEMENTS
The basal ganglia, therefore, must play a critical role in controlling and coordinating movement patterns rather than in activating the muscles to move
91
The “_________” receives sensations from the skin and muscles & produces movements INDEPENDENT of the brain
Spinal cord
92
The ANS interacts with the CNS and SNS via sets of autonomic control centres called “___________”, which acts as minibrains to control the internal organs
Ganglia
93
Why is the ENS called a second brain?
Contains a wide range of neuron types, chemical transmitters, glial cells and complex neural circuits, similar to the brain
94
List some factors that influence brain function
1. Hormones
2. Sensory experience
3. Injuries
4. Genes
5. Factors associated w/ SES
95
What important constraint determines when behaviours emerge?
***IMPORTANT
Behaviours CANNOT emerge until the requisite neural structures are sufficiently MATURE
96
What slows frontal lobe development?
1. Frontal lobe is sensitive to EPIGENETIC INFLUENCES (aversive childhood experiences ex. Physical/verbal abuse) might compromise development
2. Development correlates with ADULT INTELLIGENCE
Important features:
- reduction in cortical thickness
- increase in connectivity b/w medial regions
Greater intelligence = greatest plastic changes
97
What are Piagets stages of cognitive development?
1. Sensorimotor stage (18-24m, differentiate from outside world)
2. Preoperational stage (2-6 yrs, form mental representations)
3. Concrete operations (7-11yrs, mentally manipulate ideas about material)
4. Formal operations (sometime after 11yrs, reason in the abstract)
98
In what sequence do the forebrain structures required for learning & memory develop?
1. Displacement task
2. Non matching- to- sample learning task
3. Concurrent-discrimination learning task (neural structures MATURE SOONER for this task)
