Anatomical Orientation and the Nervous System Flashcards
1
Q
define anatomical plane
A
reference planes used to describe sections of the body: sagittal, coronal and transverse
2
Q
define sagittal plane
A
divides the body into left and right parts
3
Q
define coronal plane
A
divides the body into anterior (front) and posterior (back) parts
4
Q
define transverse plane
A
divide the body into superior (upper) and inferior (lower) parts
5
Q
define anterior
A
refers to the front side of the body
6
Q
define posterior
A
refers to the back side of the body
7
Q
define superior
A
refers to a position closer to the head or upper part of the body
8
Q
define inferior
A
refers to a position closer to the feet or lower part of the body
9
Q
define medial
A
refers to a position closer to the midline of the body
10
Q
define lateral
A
refers to a position farther from the midline of the body
11
Q
define ventral
A
refers to the front side or belly side of the body
12
Q
define dorsal
A
refers to the back side of the body
13
Q
define proximal
A
refers to a position closer to the point of attachment
14
Q
define distal
A
refers to a position farther from the point of attachment
15
Q
define superficial
A
refers to structures located closer to the outer surface of the brain
15
Q
define deep
A
refers to structures located farther from the surface and toward the core of the brain
16
Q
define internal
A
refers to structures situated within or inside the brain
17
Q
define external
A
refers to structures located on or near the outer aspects of the brain
18
Q
define palmer surface
A
anterior surface of the hand (the palm)
19
Q
define dorsal surface
A
posterior surface of the hand (back of the hand)
20
Q
define plantar surface
A
refers to the bottom or sole of the foot
21
Q
define surface
A
refers to the top side of the foot
22
Q
define cranial
A
refers to a position closer to the head or skull
23
Q
define caudal
A
refers to a position closer to the tail or lower end of the body
24
define rostral
refers to a position closer to the front of the brain or toward the nose
25
define occipital
refers to a position near or related to the back of the brain, specifically the occipital lobe
26
define unilateral
refers to a structure or condition occurring on only one side of the body
27
define bilateral
refers to structures or conditions present on both sides of the body
27
define ipsilateral
refers to structures or conditions occurring on the same side of the body
28
define contralateral
refers to structures or conditions occurring on the opposite side of the body
29
define midline
refers to unpaired structures
30
define glial cell
a non-neuronal cell in the CNS that supports, nourishes, and protects neurons
31
define astrocyte
a type of glial cell that provides structural support, regulates blood-brain barrier functions, and maintains the extracellular environment in the CNS
32
define neuron
a nerve cell responsible for transmitting electrical signals throughout the nervous system
33
define capillary
a small blood vessel in the CNS that facilitates the exchange of gases, nutrients, and waste products between the blood and brain tissue
34
define microglia
the immune cells of the CNS that acts as macrophages, clearing debris and responding to injury or infection
35
define oligodendrocyte
a type of glial cell in the CNS that produces myelin, which insulates axons to increase the speed of nerve signal transmission
36
define cerebrum
the largest part of the brain, responsible for higher cognitive functions, sensory processing, voluntary motor control, and complex behaviours
37
define diencephalon
located deep in the brain, it includes structures that relay sensory information and regulate autonomic functions
38
what does the diencephalon include?
- hypothalamus
- thalamus
- pineal gland
39
define hypothalamus
regulates vital functions such as temperature, hunger, thirst, and the release of hormones from the pituitary gland
40
define thalamus
acts as the main relay station for sensory information, directing signals to appropriate areas of the cerebral cortex
41
define pineal gland
produce melatonin, which helps regulate sleep-wake cycles
42
define brainstem
connects the brain to the spinal cord and controls basic-life sustaining functions like heart rate, breathing, and swallowing
43
what does the brainstem include?
- midbrain
- pons
- medulla oblongata
44
define midbrain
involved in visual and auditory processing, as well as motor control and coordination
45
define pons
serves as a bridge for communication between the cerebrum and cerebellum and helps regulate breathing
46
define medulla oblongata
controls autonomic functions such as heart rate, blood pressure, and respiration
47
define cerebellum
coordinates voluntary movement, balance, and motor learning, ensuring smooth and precise movements
48
define central canal
a small, fluid-filled passageway that runs the length of the spinal cord, containing cerebrospinal fluid (CSF) and connecting to the ventricles of the brain
49
define gyri/gyrus
raised ridges or folds on the surface of the brain that increase its surface area, allowing for more neurons and enhanced cognitive function
50
define sulci/sulcus
shallow grooves or indentations on the brain's surface that separate adjacent gyri and help define the boundaries of different brain regions
51
define fissures
deep grooves in the brain that divide major brain regions, such as the longitudinal fissure, which separates the two cerebral hemispheres
52
define central sulcus
a groove separating the frontal and parietal lobes, and the motor from the sensory cortext
52
define precentral gyrus
a ridge located in the frontal lobe of the brain housing the primary motor cortex responsible for voluntary motor control of skeletal muscles
53
define postcentral gyrus
a brain ridge containing the primary somatosensory cortex, responsible for processing sensory information from the body
54
define longitudinal fissure
the deep groove that divides the brain into the left and right cerebral hemispheres
55
define diencephalon
a brain region between the brainstem and cerebrum, containing the thalamus, hypothalamus, and pineal gland, involved in sensory processing and homeostasis
56
define midbrain
the part of the brainstem that controls vision, hearing, motor coordination, and regulates arousal and alertness
57
define vermis
the central part of the cerebellum that connects the two hemispheres and helps coordinate body posture and movement
58
define primary fissure
a deep groove in the cerebellum that separates its anterior and posterior lobes
59
define posterior lobe
the largest lobe of the cerebellum, involved in coordination of voluntary movements and fine motor control
60
define folia
thin, leaf-like folds on the surface of the cerebellum that increase its surface area for neural processing
61
define meninges
the three protective membranes (dura mater, arachnoid mater, pia mater) that surround and protect the brain and spinal cord
62
define dura fold
extensions of the dura mater that form partitions within the cranial cavity, stabilising and supporting the brain by separating its regions
63
what is the falx cerebri?
separates the two cerebral hemispheres along the midline
64
what is the falx cerebelli?
separates the two hemispheres of the cerebellum
65
what is the tentorium cerebelli?
separates the cerebrum from the cerebellum
66
define superior sagittal sinus
a large venous channel located along the upper edge of the flax cerebri, responsible for draining blood from the brain into the venous system
67
define straight sinus
a venous channel draining deep brain veins into the confluence of sinuses
68
define confluence
a meeting point where multiple venous sinuses in the brain converge
69
define incisura tentorii
an opening in the tentorium cerebelli that allows the brainstem to pass between the cerebrum and cerebellum
70
define diaphragma sellae
a small, circular fold of dura mater that covers the sella turcica and surrounds the pituitary gland, leaving an opening for the pituitary stalk
71
define sella turcica
a saddle-shaped depression in the sphenoid bone of the skull that houses the pituitary gland
71
what are the three common types of CNS herniations
1. transtentorial (uncal) herniation
2. tonsillar herniation
3. subfalcine herniation
72
define transverse sinus
a venous sinus located along the posterior part of the tentorium cerebelli, draining blood from the brain to the sigmoid sinuses
73
define herniation
abnormal displacement of brain tissue from one area to another, often due to increased intracranial pressure, compressing vital structure and impairing function
74
define subfalcine herniation
displacement of the brain tissue under the flax cerebri, potentially compressing the anterior cerebral artery
75
define transtentorial (uncal) herniation
displacement of brain tissue through the tentorial notch, compressing the brainstem
76
define tonsillar herniation
downward movement of cerebellar tonsils through the foramen magnum, compressing the medulla
77
symptoms of subfalcine herniation
common, headache contralateral leg weakness
78
symptoms of transtentorial (uncal) herniation
occulomotor (CN III) paresis - weakness/paralysis of occulomotor nerve, affecting eye movement
(ipsiliateral dilated pupil, abnormal EOM's), contralateral hemiparesion
79
symptoms of tonsillar herniation
obtundation - reduced level of consciousness with decreased alertness and responsiveness
80
All three meningies: dura mater, arachnoid mater and pia mater are filled with what fluid?
The subdural space is filled with subdural hematoma
The subarachnoid space is filled with cerebro-spinal fluid (CSF)
81
define periosteum
a connective tissue membrane covering bones, providing nourishment and attachment points for muscles
82
what are the two types of dura mater
- periosteal layer
- meningeal layer
83
what does the periosteal layer do?
outer layer of dura mater, provides protection and structural support
84
what does the meningeal layer do?
inner layer of dura mater, forms partitions (dural folds) within the brain to support and stabilise the brain, and creates venous sinuses for blood drainage
85
define arachnoid villus
small protrusions of the arachnoid mater into the venus sinuses that allow cerebrospinal fluid (CSF) to be absorbed into the bloodstream
86
order of layer of the brain
- skin of scalp
- periosteum
- bone of skull
- dura mater
- periosteal
- meningeal
- arachnoid mater
- pia mater
- arachnoid villus
- blood vessel
- falx cerebri
87
where does the CSF come from?
produced via the choroid plexus in the ventricles of the brain
88
what are the three ventricles involved with the CSF?
- lateral ventricle
- third ventricle
- fourth ventricle
89
what is the role of the lateral ventricle?
located in each hemisphere of the brain, they produce and circulate cerebrospinal fluid (CSF) through the brain's ventricular system
90
what is the role of the third ventricle?
located between the two halves of the diencephalon, it connects to the lateral ventricles via the interventricular foramen and helps circulate CSF
91
what is the role of the fourth ventricle?
positioned between the brainstem and cerebellum, it drains CSF into the subarachnoid space around the brain and spinal cord
92
what is the relationship between the ventricles (where CSF is produced) and the subarachnoid space?
1. specialised tissue called the choroid plexus produces the CSF
2. fluid flows from the ventricles into the subarachnoid space to protect and nourish the brain and spinal cord
93
what happens if the CSF doesn't return to the circulation?
it can cause hydrocephalus, leading to increased intracranial pressure, brain swelling and potential neurological damage
94
what is hydrocephalus usually caused by?
usually involves dysfunction in the arachnoid villi or venous sinuses - where CSF is typically reabsorbed into the bloodstream
95
what is used to treat hydrocephalus?
catheter draining CSF from the ventricles into the peritoneal cavity
96
role of the frontal lobe
responsible for executive functions such as decision-making, problem-solving, motor control, and personality
97
role of parietal lobe
processes sensory information like touch, temperature, and spatial awareness
98
role of occipital lobe
primarily responsible for visual processing and interpretation
99
role of temporal lobe
involved in auditory processing, memory, and language comprehension
100
what is the insula?
a region of the cerebral cortex located deep within the lateral sulcus, involved in processing emotions, perceptions, and autonomic functions
101
how are the cortices in the cerebral cortex usually organised?
Most primary cortices are located around the deepest sulci/ fissures such as:
- the central sulcus: surrounded by primary somatomotor & somatosensory cortices
- the lateral fissure : surrounded by primary auditory and gustatory cortices
- the calcarine sulcus: surrounded by primary visual cortex
102
role of primary somatosensory cortex
Located in the postcentral gyrus, processes sensory information from the body
103
role of primary (somato-) motor cortex
Located in the precentral gyrus, it controls voluntary muscle movements.
104
role of primary gustatory cortex
Located in the insula, it processes taste.
105
role of auditory cortex
Located in the temporal lobe, it processes auditory information
106
role of visual cortex
Located in the occipital lobe, it processes visual information
107
role of parieto-occipital fissure
separates the parietal and occipital lobes, marking the boundary between sensory processing and visual areas
108
role of lateral fissure
Separates the temporal lobe from the frontal and parietal lobes, important for organizing brain regions involved in auditory processing and language.
109
role of calcarine sulcus
Located in the occipital lobe, it contains the primary visual cortex, responsible for processing visual information
110
what is the broca's area?
region in the frontal lobe responsible for speech production and language processing
111
role of the prefrontal cortex
responsible for executive functions, such as decision-making, problem-solving, emotional regulation, and social behavior
112
what is the frontal eye field?
A region in the frontal lobe that controls voluntary eye movements and visual attention
113
what is the premotor cortex?
A region of the frontal lobe that plans and coordinates voluntary movements before they are executed by the primary motor cortex
114
what are the areas associated with vision?
- visual association area
- primary visual cortex
114
what is the visual association area?
Interprets visual information from the primary visual cortex
114
what is the primary visual cortex?
Processes raw visual information, such as light, color, and shapes
115
what are the areas associated with hearing?
- wernicke's area
- auditory association area
- primary auditory cortex
116
what is the Wernicke's area
A brain region in the temporal lobe essential for language comprehension
117
what is the auditory association area?
Interprets sounds and associates them with meaning
118
what is the primary auditory cortex?
Processes basic auditory information like pitch and volume
119
what does the central sulcus separate?
The central sulcus separates the frontal lobe from the parietal lobe.
120
Where is the primary somatomotor cortex located, and what is its function?
The primary somatomotor cortex is located in the frontal lobe and is the center for somatomotor output.
121
what is the role of the pituitary gland?
Regulates various endocrine functions by secreting hormones that control growth, metabolism, reproduction, and stress response.
122
role of the spinal cord
transmits neural signals between the brain and the body, and coordinates reflexes and motor control
123
role of the cerebellum
Coordinates voluntary movements, balance, posture, and motor learning
124
role of superior colliculus
Involved in visual processing and controlling eye movements, particularly in response to visual stimuli
125
what is the fornix?
A fiber tract connecting the hippocampus to other brain regions, involved in memory
126
what is the corpus callosum?
A fiber bundle that connects the brain's left and right hemispheres
127
define cingulate gyrus
A brain region involved in emotion, behavior, and cognitive functions
128
where is the brainstem located?
between the diencephalon (interbrain) and the spinal cord
129
define grey matter cortex
The brain's outer layer, containing neuron cell bodies, responsible for processing and integration
129
define grey matter nuclei
Clusters of neuron cell bodies within the brain, involved in processing information
130
define white matter in brain
Brain tissue made up of myelinated axons, responsible for transmitting signals between different brain regions
131
What role do oligodendrocytes and Schwann cells play in the nervous system?
Oligodendrocytes in the CNS and Schwann cells in the PNS provide insulation to nerve axons by forming the myelin sheath.
132
Why do fiber tracts in the brain and spinal cord appear white?
The myelin sheath formed by oligodendrocytes gives axonal bundles a white appearance, leading to the term "white matter."
133
Cervical cord (C1-C8)
Controls the neck, arms, diaphragm, and upper chest, with nerves responsible for movement and sensation in these areas.
134
Thoracic cord (T1-T12)
Controls the chest and abdominal muscles, as well as some back muscles, contributing to respiration and trunk stability.
135
Lumbar cord (L1-L5)
Controls the lower back, hips, and legs, influencing movement and sensation in the lower extremities.
136
Sacral cord (S1-S5)
Controls the pelvis, bowel, bladder, and sexual function, as well as sensation and movement in the lower limbs.
137
what is the cauda equina?
A bundle of nerve roots at the end of the spinal cord that innervates the lower body.
138
what are cervical and lumbar enlargements?
- Cervical enlargement: An expanded region of the spinal cord (C4-T1) that supplies nerves to the upper limbs.
- Lumbar enlargement: An expanded region of the spinal cord (T11-L2) that supplies nerves to the lower limbs.
139
what is the dural tube?
A protective membrane surrounding the spinal cord and brain.
140
What are the two main functions of white matter tracts in the spinal cord?
To transmit sensory information to the brain (ascending tracts) and motor commands from the brain (descending tracts).
141
Name the examples of sensory (ascending) tracts.
- Dorsal column-medial lemniscus system
- spinocerebellar tract
- anterolateral system
142
What is the role of the dorsal column-medial lemniscus system?
It carries fine touch, vibration, and proprioceptive sensory information to the brain.
142
Name two examples of motor (descending) pyramidal tracts.
Lateral corticospinal tract and anterior corticospinal tract.
142
What is the primary function of the lateral corticospinal tract?
To control voluntary motor movements, particularly of the limbs.
143
what is included in the Dorsal column-medial lemniscus system?
- gracile fasciculus
- cuneate fasciculus
144
what is included in the spinocerebellar tracts?
- anterior and posterior spinocerebellar tract
145
what is included in the anterolateral system?
lateral and anterior spinothalamic tract
146
what is included in the extrapyramidal tract?
- rubrospinal tract
- reticulospinal tract
- olivospinal tract
- vestibulospinal tract
147
what is the difference between the pyramidal and extrapyramidal tracts?
Pyramidal tracts: Responsible for voluntary motor control, particularly precise and skilled movements, by directly connecting the brain's motor cortex to the spinal cord
Extrapyramidal tracts: Responsible for involuntary and automatic motor control through indirect pathways involving various brainstem nuclei.
