Neurons Flashcards
What is the function of the pyramidal tract?
Initiating, controlling and stopping voluntary movement
What are the 3 major subdivisions of the brain?
hindbrain, midbrain, forebrain
What is the frontal association cortex responsible for?
Intelligence, behaviour, personality, mood, cognitive function
What is the Non-dominant hemisphere (right) responsible for?
Non-verbal language, emotional expression, spatial skills, conceptual understanding, artistic/musical skills
What is the temporal association cortex responsible for?
Memory, mood, aggression, intelligence
What is the dominant (left) hemisphere responsible for?
Speech & language
What is the Parietal Association Cortex responsible for?
3D recognition, spatial skills
Effects of injury on right/non-dominant hemisphere
Loss of non-verbal language
Speech lacks emotion
Spatial disorientation
Inability to recognise familiar objects
Loss of musical appreciation
Brocas and Wernickes areas are linked by…
Arcuate Fasciculus (arch shaped white matter tract)
What is Wernickes are responsible for?
Speech/language recognition
Where is Wernicke’s area located?
Superior temporal gyrus of temporal lobe
Lesion to Wernickes area results in…
fluent/sensory aphasia (words not understood)
Where is Brocas area?
inferior frontal gyrus of frontal lobe
What is Brocas area responsible for?
Planning of speech movements
Lesion to Brocas area results in…
Non-fluent/motor aphasia (cannot produce words)
What are the 3 parts of the brain stem?
Midbrain, pons, medulla oblongata
Lesion to arcuate fasciculus results in…
conduction aphasia (response to words heard is inappropriate)
What is Exners area responsible for?
Control of hand/finger movement associated with writing
What is the Supramarginal Language Area responsible for?
Reading
Where is Exners area?
Pre motor cortex in the frontal lobe
What is the Angular gyrus language area responsible for?
Writing
What does the lateral fissure do?
Separates temporal and frontal lobes, and partially separates temporal and parietal lobes
How many pairs of spinal nerves are there?
31
What are the 5 nerve regions named?
Cervical, thoracic, lumbar, sacral, coccygeal
What are the 3 meninges called?
Pia Matar, Arachnoid Mater, Dura Mater
How many cervical nerves are there?
8 (C1-C8)
How many thoracic nerves are there?
12 (T1-T12)
How many lumbar nerves are there?
5 (L1-L5)
How many sacral nerves are there?
5 (S1-S5)
How many coccygeal nerves are there?
1 pair
At what vertebrae does the spinal cord end?
L1-L2
What is the name for the bundle of nerves ‘hanging off’ the end of the spinal cord?
Cauda Equina
What is the name for the ‘string’ which anchors the spinal cord?
Filum Terminale Internum/Externum (externum is outside conus medullaris)
Cone at end of spinal cord is called….
Conus medullaris
What are the main symptoms of parkinsons disease?
Tremors, rigidity, flat mood, bradykinesia
What does an interneuron do?
Helps conveys motor information to move big trunk muscles
What 2 structures does the striatum consist of?
Putamen & Caudate Nucleus
What is the receptor responsible for touch sensation?
Meissners corpuscle
What is the receptor responsible for pressure sensation?
Paccinian corpsucle
What type of info does the dorsal gray matter horn convey?
Sensory
What type of info does the ventral gray matter horn convey?
Motor
What type of info does the intermediate gray matter horn convey?
Automatic
What is the result of a lesion to an UMN?
Spastic paralysis
What is the result of a lesion to a LMN?
Flaccid paralysis
What does a lesion to the spinal cord result in?
Dissociative sensory loss (sensation lost from same side for touch, opposite side for pain)
What does a lesion to the brain stem results in?
Associative sensory loss (sensation and pain lost from opposite side of body to lesion)
Where does the discriminative pathway decussate?
Internal arcuate fibres/lower medulla, at the dorsal column nuclei
Where does the non-discriminative pathway decussate?
Anterior white commissure in spinal cord
Where does the 1st neuron of the discriminative pathway terminate?
Dorsal column nuclei (gracile & caudate nucleus)
Where does the 1st neuron of the non-discriminative pathway terminate?
Substantia gelatinosa in the the dorsal gray horn
What is the function of the basal ganglia?
Coordinates smooth movements
Initiation of movement
Modification of movement
Expression of mood
What does a lesion to one side of the basal ganglia result in?
Unrefined movements of the opposite side of the body
What does a lesion to one side of the cerebellum result in?
Uncoordinated movements and loss of balance on the same side of the body
What is the medial lemniscus?
A white matter column in the brain stem
What is the corpus callosum?
A white matter tract carrying info between the 2 hemispheres
What is the cerebral aqueduct?
A narrow passage linking the 3rd and 4th ventricles
What are the superior and inferior colliculi?
The roof of the midbrain which play a small role in controlling eye movements (superior) and movements related to auditory stimuli (inferior)
Where is the primary auditory cortex located?
In the superior temporal gyrus
What are the cerebral peduncles?
White matter tracts which make up the floor of the midbrain and carry info between the cerebral cortex and the spinal cord and pons
What are the 3 types of white matter tracts?
Commisural, association, projection
What is a pallidotomy?
Destruction of globus pallidus cells
Name 1 type of commissural fibres
Corpus callosum
Name 1 type of association fibres
Arcuate fasciculus
Name 2 types of projection fibres
Spinothalamic, corticospinal
What produces CSF
Choroid plexus
The primary auditory area displays _______ arrangement
Tototopic
Higher pitch sounds are processed ________ in the brain
Deeper/more medially
Lower pitch sounds are processed ________ in the brain
Closer to the surface/more laterally
What are the 3 functions of CSF
Mechanical protection (shock absorbing)
Homeostatic function (pH)
Circulation (exchange of nutrients & waste)
Describe the pathway of CSF
Choroid plexuses in lateral ventricles -> lateral ventricles -> 3rd ventricle -> cerebral aqueduct -> 4th ventricle
Where is the 3rd ventricle located?
Between the right and left halves of the thalamus, over and around the intermediate mass
Where is the 4th ventricle located?
Between brain stem and cerebellum
What reabsorbs CSF?
Arachnoid villi of the arachnoid mater
What is a cluster of arachnoid villi called?
Arachnoid granulation
Which part of the brain contains the most neurons?
Cerebellum
What type of control does the cerebellum have? (in regards to side of body)
Ipsilateral
What is the cerebellum responsible for?
Balance & posture
Adjusts movement for error
Smooth movement
Unconscious movement
Where is the cerebral aqueduct found?
Midbrain
What are the 3 parts of the midbrain?
Colliculi, penducles, cerebral aqueduct
What are the penducles?
White matter tracts in the midbrain
What are the 2 colliculi and what are their functions?
Superior - reflex to action of sight
Inferior - reflex to action of sound
What functional area of the brain does the calcarine sulcus highlight?
Primary and secondary visual areas
What 3 structures does the hindbrain consist of?
Pons, medulla, cerebellum
What do the nuclei found in the medulla and pons control?
Breathing and heart function
Where are the frontal eye fields found?
Pre-motor cortex
Is Exners area above/more medial or below/more lateral than the frontal eye fields?
Above/more medial
What is the fattiest organ in the body?
The brain
What does the telencephalon develop into?
Cerebrum and lateral ventricles
What does the mesencephalon develop into?
Midbrain and cerebral aqueduct
What are the 2 layers of the cranial dura mater?
Periosteal (external) & Meningeal (internal)
What separates the 2 hemispheres of the cerebrum?
Falx cerebri
What separates the 2 hemispheres of the cerebellum?
Falx cerebelli
What separates the cerebrum from the cerebellum?
Tentorium cerebelli
What is the area that receives impulses for taste called?
Primary gustatory area
What is the area that receives impulses for smell called?
Primary olfactory area
What lobe contains the primary gustatory area?
Parietal
What lobe contains the primary olfactory area?
Temporal
What lobe & hemisphere contains the facial recognition area?
Temporal & non-dominant (right)
What is the area that receives impulses from the primary olfactory area called?
Orbitofrontal cortex
What 5 nuclei make up the basal ganglia?
Caudate Nucleus
Putamen
Globus pallidus
Subthalamic Nucleus
Substantia Nigra
What neurotransmitter is released from the Substantia Nigra to the striatum?
Dopamine
What neurotransmitter is released from the Striatum to the Substantia Nigra?
GABA
What neurotransmitter is released from the Striatum to the Globus pallidus?
GABA
What neurotransmitter is released from the Globus Pallidus externa to interna?
GABA
What neurotransmitter is released from the Globus Pallidus interna to the VA-VL nucleus in the thalamas?
GABA
What neurotransmitter is released from the VA-VL nucleus to the Primary Motor cortex?
Glutamate
Is Brocas area inferior (below) or superior (above) to exners area?
Inferior
What neurotransmitter is released from the primary motor cortex to the striatum?
Glutamate
What is the function of the arcuate fasciculus?
To align speech recognition/comprehension with speech production
What are the protective structures of the spinal cord?
The meninges
Cerebrospinal fluid
The vertebrae
What passes through the dorsal root of the spinal cord?
Sensory fibres of the spinal nerve
What passes through the ventral root of the spinal cord?
The motor fibres of the spinal nerve
What are the symptoms of a spastic paralysis?
Increased muscle activation and jerky movements
What region of the thalamus to both the spinothalamic and medial lemniscus pathway terminate?
Ventro posterior region
What are the symptoms of a flaccid paralysis?
Decreased muscle activation and no nervous control of muscle
What do association fibres link?
Gyri of the same hemisphere (arcuate fasciculus)
What do commisural fibres link?
Hemispheres (corpus callosum)
What do projection fibres link?
Superior and inferior structures (e.g. internal capsule)
What is the potential danger of pallidotomy as a treatment for Parkinson’s disease?
Damage to the optic nerve
What is the function of the cingulate gyrus in the brain?
Regulate emotions and pain
According to the homunculus concept, which area of the body has the largest representation in the primary motor cortex?
Hands and mouth
What is the function of the mamillary body?
Memory
What part of the brain reflexes to sight?
Superior colliculus
What part of the brain reflexes to sound?
Inferior colliculus
What does the diencephalon develop into?
Forebrain: Thalamus, hypothalamus, epithalamus, pituitary, and third ventricle
What does the metencephalon develop into?
Pons, cerebellum and upper part of the fourth ventricle
What does the myelencephalon develop into?
The medulla and lower part of the fourth ventricle
What are the 2 layers of the dura mater called (around the brain)?
External periosteal and internal meningeal
What does the hindbrain consist of?
Pons, cerebellum, medulla, fourth ventricle
What are corticopontine fibres between?
Cortex and pons
