Neuroanatomy Flashcards
(201 cards)
1
Q
Where on the Neuroaxis is the dorsal part of the brain in regards to the dorsal part of the body?
A
90 degrees
2
Q
neuroaxis
A
an imaginary line that runs the length of the spinal cord through the brain
3
Q
the 4 anaotomical directions and their 2 names of eachother
A
- Rostral/anterior structures are located toward the head
-
Caudal/posterior structures are located toward the tail.
- EX: dogs hips and caudal to its shoulders
- Dorsal/superior structures are located toward the back.
- Ventral/inferior structures are located toward the belly
- Brain is different directions
- Superior- towards the top
- Inferior- towards the feet
- Anterior- towards the front
- Posterior- towards the rear
4
Q
draw the brain and body and label the 4 directions of each
A
5
Q
Planes of section in the brain
A
- Coronal (frontal) sections divide the brain from front to back (parallel to the face).
- Horizontal (axial) sections divide the brain from top to bottom.
- Sagittal sections are parallel to the midline (between the ears) and give us a “side” view of the brain.
- Midsagittal – sagittal section dividing the brain along the midline, creating 2 approximately equal halves
6
Q
Protection of the Brain
A
- Bone
- Meninges
- CSF
- BBB
7
Q
Meninges
A
- Three layers in the central nervous system (CNS):
- Dura mater
- Arachnoid
- Pia mater
- Only two layers in the peripheral nervous system (PNS): dura and pia
8
Q
Dura Mater
A
- Out most layer of the meninges
- Kind of a mother swaddling baby, so it’s the blanket that swaddles the brain
- Leather like
- CNS & PNS
9
Q
Arachnoid Membrane
A
- Spider-weblike
- Only CNS
10
Q
Pia Matter
A
- Clear membrane that wraps around the brain
- CNS & PNS
11
Q
Ventricles of the brain
A
Produces and distributes CSF
- Lateral- lateral from midline
- Central canal- continuation for 4th ventricle
- Cerebral aqueduct- connects 3rd and 4th ventricle
12
Q
choroid plexus
A
clusters of capillary blood versicles which line the ventricles and secretes the cerebrospinal fluid
13
Q
CSF
A
- Created by choroid plexus
- Acts as a cushion
- Passes through:
- 2 lateral ventricles (one in each hemisphere)
- 3rd ventricle
-
4th ventricle
- Both in brainstem
- 4th is continuous with the Central canal of the spinal cord
- allows CSF to enter the subarachnoid space
- Leaves through the subarachnoid space/4th ventricle
- CNS and not PNS
- contained in the cerebral aqueduct
14
Q
Hydrocephalus
A
- Found in babies
- Too much water on head instead of brain matter caused by a blockage
- Prevents growth of brain
15
Q
The Brain’s Blood Supply
A
- No connected with fluid at all
- Vertebral artery- comes from back of the skull
- Ceratoid artery- oxygen blood vesicles up sides of neck to supply the brain
16
Q
Blood Brain Barrier
A
- Prevents toxins that are in the blood from getting in the brain
- No gaps between cells creating capillary in the brain
- astrocytes
17
Q
The Central Nervous System
A
includes the brain and the spinal cord
18
Q
The Peripheral Nervous System
A
the nerves exiting the brain and spinal cord that serve sensory and motor functions for the rest of the body
1.
19
Q
What’s the difference, recovery wise, if the CNS or PNS gets damaged?
A
The CNS can’t recover,
The PNS and damaged nerves can regenerate and recover function
20
Q
What does the Spinal cord consist of?
A
- Vertebrael Column
- Central Canal
- Spinal Nerves
21
Q
Vertebral column
A
the bones of the spinal column that protect and enclose the spinal cord
22
Q
Central canal
A
- in the center of the spinal cord
- Sensory enters through here with dorsal horns
- Filled with CSF
23
Q
Spinal nerves
A
- exit between the bones of the vertebral column
- Motor nerves exit through the ventral horns
- considered a mixed nerve
24
Q
5 Nerve types in spine
A
- Cervical nerves- 8 of them that serve the area of the head neck and arms
- Thoracic nerves-12, serve most of the torso
- Lumbar nerves- 5, serve the lower back and legs
- Sacral nerves-5 serve the back of the legs and genitals
- Coccygeal Nerve-
25
How many segments and nerve types are there in the spine?
31 segments and five nerve types
26
White matter
* made up of nerve fibers known as axons, the parts of neurons that carry signals to other neurons
* **Outside**
* The white look is from the mylein
* Axons from sensory neurons carry sensory information up the dorsal parts of the spinal cord
* axons from motor neurons carry movement and travel information in the ventral parts of the spinal cord
27
grey matter
* consists of areas primarily made up of cell bodies
* Inside
* Butterfly/H shaped
* the neurons found in the **dorsal** horns of the H receive sensory input
* neurons in the **ventral** horns of the H pass motor information onto the muscles
28
ventral horn cells
participate in either voluntary movement or spinal reflexes
29
Reflexes
* an involuntary action or response
* Help us sit and stand and not fall
1. patellar reflex
2. withdrawal reflex
30
patellar reflex
* the knee jerk reflex.
* managed by two neurons:
* one neuron processes **sensory** information coming into the cord from the muscle receptors
* this neuron communicates with a spinal **motor** neuron that responds to input by contracting the muscle causing your foot to kick
31
withdrawal reflex
a spinal reflex that pulls body part away from a source of pain. Produces a very rapid movement
32
Plegia
* damage to the spinal cord results in a loss of sensation and a loss of voluntary movement in parts of the body served by nerves located below the damaged area
* **_EX_**: loss of bladder and bowel control due to loss of innervation of sphincter muscles.
* **_Paraplegic_**- legs
* **_Quadriplegic_**- legs and arms
33
Brain Divisions
1. Hindbrain
2. Midbrain
3. Forebrain
34
Hindbrain
the most caudal division of the brain including the medulla, pons, and cerebellum
**_Contains:_**
1. Medulla/Myelencephalon
2. Reticular formation
3. Metencephalon/Pons
4. Cerebellum
35
Midbrain/Mesencephalon
1. Mesencephalon
2. Tectum
3. Tegmentum
4. Cerebral aqueduct
5. periaqueductal grey
6. Motor Nuclei
7. Colicoli's
36
Forebrain
* Diencephalon:
* Thalamus
* Hypothalamus
* pituitary
* Telencephalon:
* Left and right cerebral hemispheres
* limbic system
* cerebrum
37
Medulla/Myelencephalon
The gradual swelling of tissue above the cervical spinal cord marks the most caudal portion of the brain
* The vast majority of all information passing to and from higher structures of the brain passes through the medulla
* Contains a lot of **_nuclei_** or collections of cell bodies with a shared function
* damage to the medulla is fatal
* mostly white matter of spinal nerves.
* Also: Cranial nerve nuclei and nuclei of autonomic functions: **breathing heart rate, blood pressure** – so damage to this area is fatal
38
39
reticular formation
* a collection of brainstem nuclei located near the midline from rostral
* **Reticular formation** (because if you see the whole structure it look like a net – *reticulum* in Latin) – **sleep and arousal.**
* **Form many connections with the thalamus**
40
Pons
* in the Metencephalon
* rostral to the medulla
* Forms connections between the medulla and higher brain centers
* Breathing and sensory control center
* contain nuclei
41
1. cochlear nucleus
2. vestibular nucleus
3. Raphe nuclei and locus coeruleus
* **_cochlear nucleus-_** receives information about **sound** from the inner ear
* **_vestibular nucleus-_** Cell bodies that receive input about the location and movement of head from sensory neurons in the inner ear
* balance
* **_Raphe nuclei and locus coeruleus-_** influence mood, arousal, and sleep and project widely to the rest of the brain
ALL WITHIN PONS
42
Cerebellum
* Little brain
* contains more neurons than the rest of the brain combined
* resembles a tree as white matter axons form trunk and branches and grey matter or neural cell bodies form leaves
* **voluntary movements, muscle tone, regulating balance**
* Executive functions an emotional processing
**Cerebellum** traditionally associated with **movement**, but increasing understanding of its involvement in a wide range of **cognitive functions**
43
Tectum
* roof, dorsal top-half
* **Tectum** – “roof”
* **auditory and visual reflexes**
* In humans, this is comprised of
* The superior colliculus
* The inferior colliculus
44
The superior colliculus
The inferior colliculus
_Dorsal Surface of Midbrain 4 bumps:_
**1. _1+2_ The superior colliculus** is involved in **preliminary visual processing and control of eye movements** – not conscious seeing
**2. _3+4_ The inferior colliculus** is involved in **auditory processing – location of sounds**. It receives input from various brain stem nuclei and projects to the medial geniculate nucleus of the thalamus, which relays auditory information to the primary auditory cortex
45
Tegmentum
* covering, ventral bottom half
* a motor center that relays inhibitory signals to the thalamus and basal nuclei preventing unwanted body movement.
46
Cerebral aqueduct
small channel running along the midline of the brain that connects the 3rd and 4th ventricles. where CSF is contained
47
periaqueductal grey
Gray matter surrounding the cerebral aqueduct of the midbrain that is believed to play a role in the sensation of pain
* large number of receptors
* peri means around
* contains most rostral portion of the reticular formation and a number of nuclei associated with cranial nerves
48
Motor Nuclei
* **_red nucleus-_**a structure located within the reticular formation that communicates motor information between the spinal cord and the cerebellum
* **_substantia nigra-_**midbrain nuclei that communicate with the basil glinge area of the forebrain
49
Thalamus
* located in the Diencephalon
* Processes sensory information/**sensory control center**, contributes to states of arousal, and participate in learning and memory
* Reticular formation and cortex for many connections
* Damage results in a coma and seizures
* _Location_: Rostral end of brainstem
50
Hypothalamus
* **Controls the hormone/endocrine system/ANS(gland area)**, Participates in the regulation of hunger, thirst, sexual behavior, and aggression.
* Part of limbic system
* Directly connected to the pituitary gland
* Hormones are released
* Fight or flight
51
Telencephalon
* The telencephalon is also known as the cerebrum, and it consists of the largest part of the brain (it makes up about 85% of the total weight of the brain). It contains the cerebral hemispheres, and thus includes the cerebral cortex and a number of other structures lying below it (subcortical structures), along with a variety of important fiber bundles like the corpus callosum
52
Peripheral Nervous System
1. Cranial nerves
2. Spinal Nerves
3. Automatic Nervous system
53
Cranial Nerves
* **Location:** are the nerves that emerge directly from the brain (including the brainstem)
* **Function:** Cranial nerves relay information between the brain and parts of the body, primarily to and from regions of the head and neck.
* **The cranial nerves are considered components of the peripheral nervous system (PNS**)
* 12 cranial nerves enter and exit the brain
* 10th cranial nerve is **Vagus** nerve and goes all the way into our stomach and important for intenal organs
54
Spinal Nerves
* **Spinal nerves** emerge sequentially from the spinal cord with the spinal nerve closest to the head emerging in the space above the first cervical vertebra
* 31 pairs of spinal nerves exit the spinal cord to provide sensory and motor pathways to the body
* only have 2/3 layers of meninges- dura and pia matter
* CSF doesn’t surround spinal nerves
* **_2 Kinds_**: entering and exiting from head
* **_Sensory_**- entering (afferent) are outside spinal cord, **dorsal**
* **_Motor_**- exists (efferent) grey matter which are inside the spinal cord, **ventral**
55
dorsal root ganglion
a collection of cell bodies of sensory/afferent nerves located just outside the spinal cord
56
Mixed Nerve
* **_Mixed nerve-_** Spinal nerves, because it contains afferent and efferent or sensory and motor neurons
57
Autonomic Nervous System
* Provides sensory and motor innervation to glands, organs and smooth muscle
* Heart, lungs, digestive system, and other breathings are commanded by the ASN. as well as reflex if behaviors like sneezing coughing vomiting and more. AKA cruise control
* Three parts:
* Sympathetic nervous system
* parasympathetic nervous system
* Enteric nervous system
58
Sympathetic Nervous System
* Copes with emergencies and sit back preparing the body for action, arousal
* **Fight or flight system**
* Puts blood in and oxygen into the most necessary parts of the body. Puts salvation and digesting on standby
* should you be cut, you will not bleed very badly as blood vessels near the skin's surface are constricted to large muscle groups
59
Sympathetic chain
* a string of cell bodies outside the spinal cord who is axons communicate/receive input from the sympathetic neurons in the CNS and that communicate with target organs
* The chaining provides coordination for concerted, coordinated efforts.
* Messages from spinal neurons arrive at the same time So the sympathetic chain arrives at all the target organs simultaneously
* Essential for survival
60
How does the body know whether a sympathetic or parasympathetic input is being received?
* the chemical messengers is what identifies them:
* this system of my chemical messengers is critical for example if the heart is stimulated by ACH it will slow if it is stimulated by norephedrine it will speed up
61
Parasympathetic Nervous System
* Rest & Digest
* While you're sympathetic nervous system is using the energy the stored energy is provided by the parasympathetic nervous system as its job is to provide rest, repair, and energy storage
* **Location** is above and below the lumbar and thoracic regions of the spinal cord, in the brain and sacral divisions of the spinal cord
* Because the timing is not important a sympathetic chain is not needed
* The hypothalamus controls the autonomic nervous system by way of connections in the midbrain tegmentum.
62
Enteric Nervous System
* Contains a lot of neurons. The number of neurons is almost equivalent to the spinal cord
* some of the functions contribute to conscious sensations like pain hunger and satisfaction. The rest of its work remains below the level of conscious awareness
* hormones at like serotonin are released through the N trick nervous system
* Neurons embedded in the lining of the gastro intestinal system
63
The Endocrine System
* The hypothalamus directly controls the release of hormones by the glands making up the endocrine system. Including the pinyol gland the pituitary gland the thyroid glands the adrenal glands and the ice let's of languor hands in the pancreas
64
cerebral hemisphere
* **Frontal** – most anterior region
* **Parietal** – lies between the frontal and occipital lobes
* **Occipital** – posterior region, visual processing
* **Temporal** – lateral region, auditory processing
65
Boundaries between lobes
* **Sylvian fissure** – boundary of the temporal lobe
* **Central sulcus** – divides the frontal lobe from the parietal lobe
* **Postcentral gyrus** – a strip of cortex behind the central cortex, important for touch
* **Precentral gyrus** – in the frontal lobe, important for motor control
66
Strokes
67
Raphe nuclei and locus coeruleus
influence mood, arousal, and sleep and project widely to the rest of the brain
Other pontine (“in the pons”) nuclei contain cells that produce and deliver special neurotransmitters that affect general brain states – **raphe nuclei for Serotonin and locus ceruleus for Norepinephrine**
68
Basil ganglia/Corpus Striatum FUNCTION
* A collection of nuclei within the cerebral hemispheres that participate in the control of **motor** movements
* **_Enables the execution of motor programs stored by the cortex_**
degeneration occurs in Parkinson's & Huntington’s and produces disorders of movement and Psych and ADHD and OCD
69
Ganglia
a general term for collection of cell bodies
70
Basal ganglia nuclei
* Caudate Nucleus
* Putamen
* globus pallidus
* subthalamic nucleus
* nucleus accumbens/ventral striatum (bc its ventral to the rest)
* called corpus striatum because they are striped
* Substantia nigra is closely connected so it’s considered a part
71
Limbic System
* Four structures that participate in emotional behavior, motivated behavior, and learning
* 1. Hippocampus
* 2. Amygdala
* 3. Hypothalamus
* 4. Cingulate cortex
72
**_Hippocampus_**
* **_Location_**: At the midline in the four brain and at temporal lobe
* **_Function_**: learning and memory
* **_Degradation_**: as a result of stress can have memory loss called anterograde amnesia- can’t learn **NEW** facts/language/personal experience
73
**_Amygdala_**
* **_Location_**: anterior end of hippocampus, rostral temporal lobes
* **_Function_**: emotion, fear, rage, aggression, and motivation
* **_Degradation:_** abnormal emotional calmness, and an inability to respond appropriately two dangerous situations. Autism
* The Amygdala interacts with the hippocampus during the encoding and storage of emotional memories.
74
**_Cingulate Cortex_**
* **_Location:_** dorsal to the corpus callosum, inner surface of the cerebral hemispheres
* **_Function:_** fold of cortical tissue that contains nerve cells and have two types:
* **_Anterior CC-_** decision making, action, emotion, anticipation for reward, empathy
* **_Posterior CC-_** eye movements, spatial orientation, and memory
* **_degradation:_** Alzheimer's disease
75
Olfactory bulbs
* receive and process emotional information about smell
* **_Location:_** base of the forebrain
76
anterior commissure
small band of axons keeping two hemipsheres connected
77
The Cortex
* outer layer of the cerebral hemispheres, thin layer of gray matter, contain the cerebral hemispheres
78
**_Gyri_**
hills of the cortex
79
Sulci/fissures
valleys of the cortex (fissures are deep)
80
Fissure
* a large sulcus that are the boundries of the temporal lobe and frontal/parietal
81
Central sulcus
* _–_ divides the frontal lobe from the parietal lobe
* it is wrinkled because it provides more surface area for cortical cells.
Cells are organized in layers: (numbered from outer to inner
82
Layers of the Cortex
* **_Layer I_**- no cell bodies, made up of nerve fibers of the cells forming connections with other layers
* Has no grey matter
* **_Layers II and IV-_** lots of Granule cells
* **_Layers III and V-_** large numbers of pyramidal cells
* **_provide most of the output from an area of the cortex to other parts of the nervous system_**
* **_Layer VI-_** many types of neurons which merge into the white matter below the cortical layers
83
Grey and white matter
* **_Grey matter-_** outside, cell bodies
* **_White matter-_** inside/underneath- axons
* **Underneath layer 6**
* **_EXACT OPPOSITE FOR SPINE-_** because of structure and function. There are different functions for the brain and the spine.
84
Granule Cell
* Their _short_ axons do not leave the cortex.
* Granule/Stellate cells are the principal _interneurons/Multipolar_ of the neocortex
* Smaller
* Wide assortment of shapes
85
Pyramidal cell
* shaped like a pyramid and are aligned organized way and do not cancel each other out.
* Have _long axons_ that _leave the cortex_ to reach either _other cortical areas_ or to various _subcortical sites_.
* Therefore, pyramidal cells are the _principal output neurons_
* Really important for EEG’s
* Schizophrenia has unorganized pyramidal cells
* huge
86
Frontal lobe
rostral of the lobes. Caudal boundary is marked by central sulcus
* it can localize a number of specific functions in areas of the cerebral cortex
* higher level cognitive processes like planning of behavior attention and judgment
* Sensory and motor information is lateralized (and flipped!).
* Language and logical thought: **typically left hemisphere.**
* Intuitive, spatial processing \> **right hemisphere.**
87
Parietal
on the other side of the central sulcus
sensory perception and integration, including the management of taste, hearing, sight, touch, and smell. It is home to the brain's primary somatic sensory cortex (see image 2), a region where the brain interprets input from other areas of the body
88
Temporal Lobe
ventral direction, separated from the frontal lobe by lateral sulcus
processing auditory information and with the encoding of memory
89
Occipital Lobe
back of the cortex
visual processing area of the brain
90
Insula
the cortex located within the lateral sulcus between the frontal parietal and temporal lobes. Referred to as the 5th lobe.
91
longitudinal Fissure
separating the two cerebral hemispheres along the dorsal midline, opposite of corpus collosum
92
**sensory cortex**
* **_Primary visual cortex:_** occipital
* **_primary auditory cortex:_** temporal
**_primary sodemosensory cortex_**: **post central gyrus** of the parietal, highest level of processing for information about touch, pain, position, and skin temperature
93
**motor cortex**
* **primary motor cortex:** located in the **precentral** **gyrus** in the frontal lobe
* **Precentral gyrus** – in the frontal lobe, important for motor control
* Both hemispheres have all lobes and structures. So, we have two thalamus’s
94
**association cortex**
Regions of cerebral cortex providing more complex processing of sensory information
95
dorsolateral prefrontal cortex
* - located to the top and side of the frontal lobes
* attention and working memory and planning of behavior
* **_damaged_**: apathy, personality change, and lack of ability to plan
96
orbitofrontal cortex
* -located above and behind the eyes
* control and delayed gratification
* damaged: emotional disturbances and impulsiveness, serial killers
* both of these maintain extensive reciprocal connections with the limbic system, the basil ganglia, and other parts of the cortex
97
Broca’s areas
* near the primary motor cortex in the frontal lobe that participates in speech production.
* left hemisphere
* Damage: difficulty speaking
98
_Akinetopsia_
- motion blindness.
Two relevant visual areas for motion processing which might be damaged: V5 and V1. (ASK ABOUT SUPERIOR COLLOCOLI)
99
_Agnosia_
causes the victims to lose the ability to recognize visual objects.
100
Prosopagnosia
* the inability to recognize faces (even their own face!). The result of abnormalities, damage, or impairment in the right fusiform gyrus.
* All ex of localization of function
101
90 degrees
Where on the Neuroaxis is the dorsal part of the brain in regards to the dorsal part of the body?
102
an imaginary line that runs the length of the spinal cord through the brain
neuroaxis
103
1. **Rostral/anterior** structures are located toward the head
2. **Caudal/posterior** structures are located toward the tail.
1. **EX:** dogs hips and caudal to its shoulders
3. **Dorsal/superior** structures are located toward the back.
4. **Ventral/inferior** structures are located toward the belly
* **Brain is different directions**
* **Superior-** towards the top
* **Inferior-** towards the feet
* **Anterior-** towards the front
* **Posterior-** towards the rear
the 4 anaotomical directions and their 2 names of eachother
104
draw the brain and body and label the 4 directions of each
105
1. **Coronal (frontal)** sections divide the brain from front to back (parallel to the face).
2. **Horizontal (axial)** sections divide the brain from top to bottom.
3. **Sagittal** sections are parallel to the midline (between the ears) and give us a “side” view of the brain.
4. **Midsagittal – sagittal section dividing the brain along the midline, creating 2 approximately equal halves**
Planes of section in the brain
106
1. Bone
2. Meninges
3. CSF
4. BBB
Protection of the Brain
107
* Three layers in the central nervous system (CNS):
1. **Dura mater**
2. **Arachnoid**
3. **Pia mater**
* Only two layers in the peripheral nervous system (PNS): dura and pia
Meninges
108
* Out most layer of the meninges
* Kind of a mother swaddling baby, so it’s the blanket that swaddles the brain
* Leather like
* CNS & PNS
Dura Mater
109
* Spider-weblike
* Only CNS
Arachnoid Membrane
110
* Clear membrane that wraps around the brain
* CNS & PNS
Pia Matter
111
Produces and distributes CSF
* **_Lateral_**- lateral from midline
* **_Central canal_**- continuation for 4th ventricle
* **_Cerebral aqueduct_**- connects 3rd and 4th ventricle
Ventricles of the brain
112
clusters of capillary blood versicles which line the ventricles and secretes the cerebrospinal fluid
choroid plexus
113
* Created by choroid plexus
* Acts as a cushion
* Passes through:
* **2 lateral ventricles (one in each hemisphere)**
* **3rd ventricle**
* **4th ventricle**
* **Both in brainstem**
* 4th is continuous with the Central canal of the spinal cord
* allows CSF to enter the subarachnoid space
* Leaves through the subarachnoid space/4th ventricle
* CNS and not PNS
* contained in the cerebral aqueduct
CSF
114
* Found in babies
* Too much water on head instead of brain matter caused by a blockage
* Prevents growth of brain
Hydrocephalus
115
* No connected with fluid at all
* Vertebral artery- comes from back of the skull
* Ceratoid artery- oxygen blood vesicles up sides of neck to supply the brain
The Brain’s Blood Supply
116
* Prevents toxins that are in the blood from getting in the brain
* No gaps between cells creating capillary in the brain
* astrocytes
Blood Brain Barrier
117
includes the brain and the spinal cord
The Central Nervous System
118
the nerves exiting the brain and spinal cord that serve sensory and motor functions for the rest of the body
1.
The Peripheral Nervous System
119
The CNS can't recover,
The PNS and damaged nerves can regenerate and recover function
What's the difference, recovery wise, if the CNS or PNS gets damaged?
120
1. Vertebrael Column
2. Central Canal
3. Spinal Nerves
What does the Spinal cord consist of?
121
the bones of the spinal column that protect and enclose the spinal cord
Vertebral column
122
* in the center of the spinal cord
* Sensory enters through here with dorsal horns
* Filled with CSF
Central canal
123
* exit between the bones of the vertebral column
* Motor nerves exit through the ventral horns
* considered a mixed nerve
Spinal nerves
124
1. **_Cervical nerves_**- 8 of them that serve the area of the head neck and arms
2. **_Thoracic nerves-_**12, serve most of the torso
3. **_Lumbar nerves-_** 5, serve the lower back and legs
4. **_Sacral nerves-_**5 serve the back of the legs and genitals
5. **_Coccygeal Nerve-_**
5 Nerve types in spine
125
31 segments and five nerve types
How many segments and nerve types are there in the spine?
126
* made up of nerve fibers known as axons, the parts of neurons that carry signals to other neurons
* **Outside**
* The white look is from the mylein
* Axons from sensory neurons carry sensory information up the dorsal parts of the spinal cord
* axons from motor neurons carry movement and travel information in the ventral parts of the spinal cord
White matter
127
* consists of areas primarily made up of cell bodies
* Inside
* Butterfly/H shaped
* the neurons found in the **dorsal** horns of the H receive sensory input
* neurons in the **ventral** horns of the H pass motor information onto the muscles
grey matter
128
participate in either voluntary movement or spinal reflexes
ventral horn cells
129
* an involuntary action or response
* Help us sit and stand and not fall
1. patellar reflex
2. withdrawal reflex
Reflexes
130
* the knee jerk reflex.
* managed by two neurons:
* one neuron processes **sensory** information coming into the cord from the muscle receptors
* this neuron communicates with a spinal **motor** neuron that responds to input by contracting the muscle causing your foot to kick
patellar reflex
131
a spinal reflex that pulls body part away from a source of pain. Produces a very rapid movement
withdrawal reflex
132
* damage to the spinal cord results in a loss of sensation and a loss of voluntary movement in parts of the body served by nerves located below the damaged area
* **_EX_**: loss of bladder and bowel control due to loss of innervation of sphincter muscles.
* **_Paraplegic_**- legs
* **_Quadriplegic_**- legs and arms
Plegia
133
1. Hindbrain
2. Midbrain
3. Forebrain
Brain Divisions
134
the most caudal division of the brain including the medulla, pons, and cerebellum
**_Contains:_**
1. Medulla/Myelencephalon
2. Reticular formation
3. Metencephalon/Pons
4. Cerebellum
Hindbrain
135
1. Mesencephalon
2. Tectum
3. Tegmentum
4. Cerebral aqueduct
5. periaqueductal grey
6. Motor Nuclei
7. Colicoli's
Midbrain/Mesencephalon
136
* Diencephalon:
* Thalamus
* Hypothalamus
* pituitary
* Telencephalon:
* Left and right cerebral hemispheres
* limbic system
* cerebrum
Forebrain
137
The gradual swelling of tissue above the cervical spinal cord marks the most caudal portion of the brain
* The vast majority of all information passing to and from higher structures of the brain passes through the medulla
* Contains a lot of **_nuclei_** or collections of cell bodies with a shared function
* damage to the medulla is fatal
* mostly white matter of spinal nerves.
* Also: Cranial nerve nuclei and nuclei of autonomic functions: **breathing heart rate, blood pressure** – so damage to this area is fatal
Medulla/Myelencephalon
138
139
* a collection of brainstem nuclei located near the midline from rostral
* **Reticular formation** (because if you see the whole structure it look like a net – *reticulum* in Latin) – **sleep and arousal.**
* **Form many connections with the thalamus**
reticular formation
140
* in the Metencephalon
* rostral to the medulla
* Forms connections between the medulla and higher brain centers
* Breathing and sensory control center
* contain nuclei
Pons
141
* **_cochlear nucleus-_** receives information about **sound** from the inner ear
* **_vestibular nucleus-_** Cell bodies that receive input about the location and movement of head from sensory neurons in the inner ear
* balance
* **_Raphe nuclei and locus coeruleus-_** influence mood, arousal, and sleep and project widely to the rest of the brain
ALL WITHIN PONS
1. cochlear nucleus
2. vestibular nucleus
3. Raphe nuclei and locus coeruleus
142
* Little brain
* contains more neurons than the rest of the brain combined
* resembles a tree as white matter axons form trunk and branches and grey matter or neural cell bodies form leaves
* **voluntary movements, muscle tone, regulating balance**
* Executive functions an emotional processing
**Cerebellum** traditionally associated with **movement**, but increasing understanding of its involvement in a wide range of **cognitive functions**
Cerebellum
143
* roof, dorsal top-half
* **Tectum** – “roof”
* **auditory and visual reflexes**
* In humans, this is comprised of
* The superior colliculus
* The inferior colliculus
Tectum
144
_Dorsal Surface of Midbrain 4 bumps:_
**1. _1+2_ The superior colliculus** is involved in **preliminary visual processing and control of eye movements** – not conscious seeing
**2. _3+4_ The inferior colliculus** is involved in **auditory processing – location of sounds**. It receives input from various brain stem nuclei and projects to the medial geniculate nucleus of the thalamus, which relays auditory information to the primary auditory cortex
The superior colliculus
The inferior colliculus
145
* covering, ventral bottom half
* a motor center that relays inhibitory signals to the thalamus and basal nuclei preventing unwanted body movement.
Tegmentum
146
small channel running along the midline of the brain that connects the 3rd and 4th ventricles. where CSF is contained
Cerebral aqueduct
147
Gray matter surrounding the cerebral aqueduct of the midbrain that is believed to play a role in the sensation of pain
* large number of receptors
* peri means around
* contains most rostral portion of the reticular formation and a number of nuclei associated with cranial nerves
periaqueductal grey
148
* **_red nucleus-_**a structure located within the reticular formation that communicates motor information between the spinal cord and the cerebellum
* **_substantia nigra-_**midbrain nuclei that communicate with the basil glinge area of the forebrain
Motor Nuclei
149
* located in the Diencephalon
* Processes sensory information/**sensory control center**, contributes to states of arousal, and participate in learning and memory
* Reticular formation and cortex for many connections
* Damage results in a coma and seizures
* _Location_: Rostral end of brainstem
Thalamus
150
* **Controls the hormone/endocrine system/ANS(gland area)**, Participates in the regulation of hunger, thirst, sexual behavior, and aggression.
* Part of limbic system
* Directly connected to the pituitary gland
* Hormones are released
* Fight or flight
Hypothalamus
151
* The telencephalon is also known as the cerebrum, and it consists of the largest part of the brain (it makes up about 85% of the total weight of the brain). It contains the cerebral hemispheres, and thus includes the cerebral cortex and a number of other structures lying below it (subcortical structures), along with a variety of important fiber bundles like the corpus callosum
Telencephalon
152
1. Cranial nerves
2. Spinal Nerves
3. Automatic Nervous system
Peripheral Nervous System
153
* **Location:** are the nerves that emerge directly from the brain (including the brainstem)
* **Function:** Cranial nerves relay information between the brain and parts of the body, primarily to and from regions of the head and neck.
* **The cranial nerves are considered components of the peripheral nervous system (PNS**)
* 12 cranial nerves enter and exit the brain
* 10th cranial nerve is **Vagus** nerve and goes all the way into our stomach and important for intenal organs
Cranial Nerves
154
* **Spinal nerves** emerge sequentially from the spinal cord with the spinal nerve closest to the head emerging in the space above the first cervical vertebra
* 31 pairs of spinal nerves exit the spinal cord to provide sensory and motor pathways to the body
* only have 2/3 layers of meninges- dura and pia matter
* CSF doesn’t surround spinal nerves
* **_2 Kinds_**: entering and exiting from head
* **_Sensory_**- entering (afferent) are outside spinal cord, **dorsal**
* **_Motor_**- exists (efferent) grey matter which are inside the spinal cord, **ventral**
Spinal Nerves
155
a collection of cell bodies of sensory/afferent nerves located just outside the spinal cord
dorsal root ganglion
156
* **_Mixed nerve-_** Spinal nerves, because it contains afferent and efferent or sensory and motor neurons
Mixed Nerve
157
* Provides sensory and motor innervation to glands, organs and smooth muscle
* Heart, lungs, digestive system, and other breathings are commanded by the ASN. as well as reflex if behaviors like sneezing coughing vomiting and more. AKA cruise control
* Three parts:
* Sympathetic nervous system
* parasympathetic nervous system
* Enteric nervous system
Autonomic Nervous System
158
* Copes with emergencies and sit back preparing the body for action, arousal
* **Fight or flight system**
* Puts blood in and oxygen into the most necessary parts of the body. Puts salvation and digesting on standby
* should you be cut, you will not bleed very badly as blood vessels near the skin's surface are constricted to large muscle groups
Sympathetic Nervous System
159
* a string of cell bodies outside the spinal cord who is axons communicate/receive input from the sympathetic neurons in the CNS and that communicate with target organs
* The chaining provides coordination for concerted, coordinated efforts.
* Messages from spinal neurons arrive at the same time So the sympathetic chain arrives at all the target organs simultaneously
* Essential for survival
Sympathetic chain
160
* the chemical messengers is what identifies them:
* this system of my chemical messengers is critical for example if the heart is stimulated by ACH it will slow if it is stimulated by norephedrine it will speed up
How does the body know whether a sympathetic or parasympathetic input is being received?
161
* Rest & Digest
* While you're sympathetic nervous system is using the energy the stored energy is provided by the parasympathetic nervous system as its job is to provide rest, repair, and energy storage
* **Location** is above and below the lumbar and thoracic regions of the spinal cord, in the brain and sacral divisions of the spinal cord
* Because the timing is not important a sympathetic chain is not needed
* The hypothalamus controls the autonomic nervous system by way of connections in the midbrain tegmentum.
Parasympathetic Nervous System
162
* Contains a lot of neurons. The number of neurons is almost equivalent to the spinal cord
* some of the functions contribute to conscious sensations like pain hunger and satisfaction. The rest of its work remains below the level of conscious awareness
* hormones at like serotonin are released through the N trick nervous system
* Neurons embedded in the lining of the gastro intestinal system
Enteric Nervous System
163
* The hypothalamus directly controls the release of hormones by the glands making up the endocrine system. Including the pinyol gland the pituitary gland the thyroid glands the adrenal glands and the ice let's of languor hands in the pancreas
The Endocrine System
164
* **Frontal** – most anterior region
* **Parietal** – lies between the frontal and occipital lobes
* **Occipital** – posterior region, visual processing
* **Temporal** – lateral region, auditory processing
cerebral hemisphere
165
* **Sylvian fissure** – boundary of the temporal lobe
* **Central sulcus** – divides the frontal lobe from the parietal lobe
* **Postcentral gyrus** – a strip of cortex behind the central cortex, important for touch
* **Precentral gyrus** – in the frontal lobe, important for motor control
Boundaries between lobes
166
Strokes
167
influence mood, arousal, and sleep and project widely to the rest of the brain
Other pontine (“in the pons”) nuclei contain cells that produce and deliver special neurotransmitters that affect general brain states – **raphe nuclei for Serotonin and locus ceruleus for Norepinephrine**
Raphe nuclei and locus coeruleus
168
* A collection of nuclei within the cerebral hemispheres that participate in the control of **motor** movements
* **_Enables the execution of motor programs stored by the cortex_**
degeneration occurs in Parkinson's & Huntington’s and produces disorders of movement and Psych and ADHD and OCD
Basil ganglia/Corpus Striatum FUNCTION
169
a general term for collection of cell bodies
Ganglia
170
* Caudate Nucleus
* Putamen
* globus pallidus
* subthalamic nucleus
* nucleus accumbens/ventral striatum (bc its ventral to the rest)
* called corpus striatum because they are striped
* Substantia nigra is closely connected so it’s considered a part
Basil ganglia nuclei
171
* Four structures that participate in emotional behavior, motivated behavior, and learning
* 1. Hippocampus
* 2. Amygdala
* 3. Hypothalamus
* 4. Cingulate cortex
Limbic System
172
* **_Location_**: At the midline in the four brain and at temporal lobe
* **_Function_**: learning and memory
* **_Degradation_**: as a result of stress can have memory loss called anterograde amnesia- can’t learn **NEW** facts/language/personal experience
**_Hippocampus_**
173
* **_Location_**: anterior end of hippocampus, rostral temporal lobes
* **_Function_**: emotion, fear, rage, aggression, and motivation
* **_Degradation:_** abnormal emotional calmness, and an inability to respond appropriately two dangerous situations. Autism
* The Amygdala interacts with the hippocampus during the encoding and storage of emotional memories.
**_Amygdala_**
174
* **_Location:_** dorsal to the corpus callosum, inner surface of the cerebral hemispheres
* **_Function:_** fold of cortical tissue that contains nerve cells and have two types:
* **_Anterior CC-_** decision making, action, emotion, anticipation for reward, empathy
* **_Posterior CC-_** eye movements, spatial orientation, and memory
* **_degradation:_** Alzheimer's disease
**_Cingulate Cortex_**
175
* receive and process emotional information about smell
* **_Location:_** base of the forebrain
Olfactory bulbs
176
small band of axons keeping two hemipsheres connected
anterior commissure
177
* outer layer of the cerebral hemispheres, thin layer of gray matter, contain the cerebral hemispheres
The Cortex
178
hills of the cortex
**_Gyri_**
179
valleys of the cortex (fissures are deep)
Sulci/fissures
180
* a large sulcus that are the boundries of the temporal lobe and frontal/parietal
Fissure
181
* _–_ divides the frontal lobe from the parietal lobe
* it is wrinkled because it provides more surface area for cortical cells.
Cells are organized in layers: (numbered from outer to inner
Central sulcus
182
* **_Layer I_**- no cell bodies, made up of nerve fibers of the cells forming connections with other layers
* Has no grey matter
* **_Layers II and IV-_** lots of Granule cells
* **_Layers III and V-_** large numbers of pyramidal cells
* **_provide most of the output from an area of the cortex to other parts of the nervous system_**
* **_Layer VI-_** many types of neurons which merge into the white matter below the cortical layers
Layers of the Cortex
183
* **_Grey matter-_** outside, cell bodies
* **_White matter-_** inside/underneath- axons
* **Underneath layer 6**
* **_EXACT OPPOSITE FOR SPINE-_** because of structure and function. There are different functions for the brain and the spine.
Grey and white matter
184
* Their _short_ axons do not leave the cortex.
* Granule/Stellate cells are the principal _interneurons/Multipolar_ of the neocortex
* Smaller
* Wide assortment of shapes
Granule Cell
185
* shaped like a pyramid and are aligned organized way and do not cancel each other out.
* Have _long axons_ that _leave the cortex_ to reach either _other cortical areas_ or to various _subcortical sites_.
* Therefore, pyramidal cells are the _principal output neurons_
* Really important for EEG’s
* Schizophrenia has unorganized pyramidal cells
* huge
Pyramidal cell
186
rostral of the lobes. Caudal boundary is marked by central sulcus
* it can localize a number of specific functions in areas of the cerebral cortex
* higher level cognitive processes like planning of behavior attention and judgment
* Sensory and motor information is lateralized (and flipped!).
* Language and logical thought: **typically left hemisphere.**
* Intuitive, spatial processing \> **right hemisphere.**
Frontal lobe
187
on the other side of the central sulcus
sensory perception and integration, including the management of taste, hearing, sight, touch, and smell. It is home to the brain's primary somatic sensory cortex (see image 2), a region where the brain interprets input from other areas of the body
Parietal
188
ventral direction, separated from the frontal lobe by lateral sulcus
processing auditory information and with the encoding of memory
Temporal Lobe
189
back of the cortex
visual processing area of the brain
Occipital Lobe
190
the cortex located within the lateral sulcus between the frontal parietal and temporal lobes. Referred to as the 5th lobe.
Insula
191
separating the two cerebral hemispheres along the dorsal midline, opposite of corpus collosum
longitudinal Fissure
192
* **_Primary visual cortex:_** occipital
* **_primary auditory cortex:_** temporal
**_primary sodemosensory cortex_**: **post central gyrus** of the parietal, highest level of processing for information about touch, pain, position, and skin temperature
**sensory cortex**
193
* **primary motor cortex:** located in the **precentral** **gyrus** in the frontal lobe
* **Precentral gyrus** – in the frontal lobe, important for motor control
* Both hemispheres have all lobes and structures. So, we have two thalamus’s
**motor cortex**
194
Regions of cerebral cortex providing more complex processing of sensory information
**association cortex**
195
* - located to the top and side of the frontal lobes
* attention and working memory and planning of behavior
* **_damaged_**: apathy, personality change, and lack of ability to plan
dorsolateral prefrontal cortex
196
* -located above and behind the eyes
* control and delayed gratification
* damaged: emotional disturbances and impulsiveness, serial killers
* both of these maintain extensive reciprocal connections with the limbic system, the basil ganglia, and other parts of the cortex
orbitofrontal cortex
197
* near the primary motor cortex in the frontal lobe that participates in speech production.
* left hemisphere
* Damage: difficulty speaking
Broca’s areas
198
- motion blindness.
Two relevant visual areas for motion processing which might be damaged: V5 and V1. (ASK ABOUT SUPERIOR COLLOCOLI)
_Akinetopsia_
199
causes the victims to lose the ability to recognize visual objects.
_Agnosia_
200
* the inability to recognize faces (even their own face!). The result of abnormalities, damage, or impairment in the right fusiform gyrus.
* All ex of localization of function
Prosopagnosia
201
arcuate fasciculus
One of the key roles of the arcuate fasciculus is connecting Broca's and Wernicke's areas, which are involved in producing and understanding language
