Neuroanatomy Flashcards
Cranial Nerve 1
- Olfactory
- smell
Cranial Nerve 2
- Optic
- Vision
Cranial nerve 3
- Oculomotor
- eye movement
Cranial nerve 4
- Trochlear
- eye movement
Cranial nerve 5
- Trigeminal
- masticatory movements and facial sensation
Cranial nerve 6
- Abducens
- eye movement
Cranial nerve 7
- Facial
- Facial movement and sensation
Cranial nerve 8
- Auditory vestibular
- hearing and balance
Cranial nerve 9
- Glossopharyngeal
- tongue and pharynx movement and sensation
Cranial nerve 10
- Vagus
- heart, blood vessels, viscera, movement of larynx and pharynx
Cranial nerve 11
- spinal accessory
- neck muscles
Cranial nerve 12
- Hypoglossal
- tongue muscles
Basic functions of the brain
- creating a sensory reality
- integrating information
- producing behaviour
Brain anatomical orientations
- superior/dorsal ^ vs inferior/ventral
- anterior/rostral vs posterior/caudal
- at brainstem rotates 90 degrees (dorsal is now towards back of head)
The layers of the coverings of the brain
- scalp
- skull
- dura mater
- arachnoid mater
- pia mater
White matter
- areas of the nervous system rich in fat-sheathed neural axons
Gray matter
- areas of the nervous system predominately composed of cell bodies and blood vessels
Lobes
- frontal, parietal, occipital, temporal
Planes of view
- horizontal
- sagittal
- coronal
Brodmann area 17
- primary visual
Brodmann area 18, 19 20, 21, 37
- secondary vision
Brodmann area 41
- primary audition
Brodmann area 22, 42
- secondary audition
Brodmann area 1, 2, 3
- primary body sensation
Brodmann area 5, 7
- secondary body sensation
Brodmann area 7, 22, 37, 39, 40
- tertiary sensation
Brodmanm area 4
- primary motor
Brodmann area 6
- secondary motor
Brodmann area 8
- eye movement (motor)
Brodmann area 44
- speech (motor)
Brodmann area 9, 10, 11, 45, 46, 47
- tertiary motor
Anterior circulation
- bilaterally paired internal carotid arteries
- aorta brachiocephalic artery -> common carotid artery -> internal carotid artery (-> brain through carotid foramen) or external carotid artery
Posterior circulation
- bilaterally paired vertebral arteries
- aorta brachiocephalic artery -> subclavian arteries -> vertebral arteries -> basilar artery (brain)
Regions supplied by ACA (anterior cerebral artery)
- frontal lobe
- anterior parietal lobe
Arteries branching from ACA
- callosomarginal artery
- pericallosal artery
Regions supplied by the PCA (posterior cerebral artery)
- inferior and medial temporal lobe
- occipital lobe
Regions supplied by the MCA (middle cerebral artery)
- lateral frontal lobe (by MCA superior division cortical branches)
- lateral temporal lobe and parts of the parietal lobe (by MCA inferior division cortical branches)
Which arteries close the circle of willis?
- anterior communicating artery (AComm)
- posterior communicating artery (PComm)
What areas does the anterior choroidal artery feed?
- GP, putamen, internal capsule thalamus
What arteries are derived from the internal carotid artery?
- anterior choroidal artery, middle cerebral artery stem (M1), lenticulostriate arteries
What areas does the recurrent artery of Heubner feed?
- caudate putamen, GP internal capsule
What are the main venous drainages of the hemispheres?
- superficial veins: superior sagittal sinus, cavernous sinus
- internal jugular vein
- deep veins: great vein of Galen
Where are the two lateral ventricles? What do they contain?
- one inside each cerebral hemisphere
- choroid plexus: vascular structure that produces CSF
Where is the third ventricle?
- located within the diencephalon
- surrounded by the thalamus and hypothalamus
Where is the fourth ventricle?
- located in the hindbrain
- surrounded by the pons and medulla and cerebellum
How is the CSF circulated?
- lateral ventricles (choroid ventricles)
- through foramen of monro
- to third ventricle
- through sylvian aqueduct
- to fourth ventricle
- through foramen of Luschka and Magendie
- to subarachnoid space
- through arachnoid granulations
- to blood stream
How is the cerebral spinal fluid circulated? (2)
- CSF produced by choroid plexus
- CSF flows through ventricles to subarachnoid space via median and lateral apertures (some flows through canal of spinal cord)
- CSF flows through subarachnoid space
- CSF is absorbed into dural sinuses via arachnoid villi
What are the principle structures of the forebrain?
- cerebral cortex
- basal ganglia
- limbic system
What are the key features of the cerebrum?
- most complex mental processes (sensation, perception, thinking, and planning)
- largest brain structure
- most recently evolved brain structure
What are the surface features of the cerebrum?
- gyrus: a wrinkle
- sulcus: a shallow crack
- fissure: a deep crack
The two halves of the cortex are called? And they are joined by?
- hemispheres
- corpus callosum
What are the main features of the layers of the cortex?
- 6 layers
- different layers have different cell types
- density of cells varies with layer
- organized in columns
Which layers are involved in integrative functions?
- I, II, III
Which layers are involved in input of sensory information?
- IV
Which layers are involved in output to other parts of the brain?
- V, VI
Which layers are larger in the motor cortex?
- V and VI
Which layers are larger in the sensory cortex?
- IV
What are the main areas of the occipital lobe?
- primary visual cortex
- visual association cortex (higher processing of visual information)
What two streams stem from the occipital lobe?
- How/dorsal stream: motion
- What/ventral stream: colour, shape, size
What contributes to both them dorsal and ventral streams?
- information from the secondary somatosensory cortex
- contributes to dorsal stream by specifying the movement used for grasping a target
- contributes to ventral stream by providing information about object size and shape
What are the main areas/functions of the parietal lobe?
- somatosensory cortex (tactile and position information processing)
- language comprehension
- spatial orientation and perception
Where does primary somatosensory cortex receive information from?
- from the body
Where does the secondary somatosensory cortex receive sensory information from?
- the primary somatosensory cortex
What are the main areas/functions of the temporal lobe?
- primary auditory cortex
- wernicke’s area (language comprehension)
- higher visual processing
- learning and memory
What are main areas/functions of the frontal lobe?
- primary motor cortex (voluntary movements)
- premotor cortex (initiation of movement)
- Broca’s area (written and spoken language)
- prefrontal cortex (personality and insight/foresight)
What are the functions of the motor areas?
- prefrontal cortex plans movements
- premotor cortex organizes movement sequences
- motor cortex produces specific movements
What are main areas of the prefrontal cortex?
- dorsolateral prefrontal
- inferior/ventral prefrontal
- ventromedial and orbitolateral prefrontal
What are the functions of the dorsolateral prefrontal?
- mediates internal cues for initiating actions
- working memory
- damage causes perseveration
What is the function of the inferior/ventral prefrontal?
- influences autonomic functioning
What are the functions of the ventromedial and orbitolateral prefrontal?
- reward-based learning
- emotional responses such as apathy
What are the functions of the association cortex?
- responsible for cognition
- everything but primary sensory or primary motor cortices
- unique information processing
What kind of unique information processing does the association cortex do?
- highly processed information
- detailed knowledge about the external and internal world
- inputs from the thalamic regions that received inputs from other cortical regions
What are the three major divisions of the association cortex?
- parietal association cortex
- temporal association cortex
- frontal association
What is the function of the parietal association cortex?
- paying attention to external and internal environment
What is the function of the temporal association cortex?
- identification of stimuli
What is the function of the frontal association cortex?
- planning responses
What functions is the limbic system involved with?
- memory, motivation and emotion
What anatomical structures are related to the limbic system?
- hippocampus
- hypothalamus
- amygdala
- septum
- cingulate cortex
- fornix
Limbic system: Hippocampus
- lies inside temporal lobes
- involved in learning and memory
- important for consolidation (but not retrieval or storage)
Limbic system: Amygdala
- lies inside front of temporal lobes
- controls reactions to biologically significant stimuli - emotional system (food, foes, mates)
- removal has decreased aggression
What are the three interconnected nuclei of the basal ganglia?
- caudate nucleus
- putamen
- globus pallidus
What is the basal ganglia’s function?
- movement control
What diseases are caused by abnormalities in basal ganglia function?
- Parkinson’s and Huntington’s disease
What are the functional divisions of the brainstem?
- diencephalon
- midbrain
- hindbrain
What are the principle structures of the diencephalon?
- thalamus
- hypothalamus
- epithalamus (pineal gland)
- subthalamus
What are the principle structures of the midbrain?
- tectum
- tegmentum
What are the principle structures of the hindbrain?
- cerebellum
- pons
- medulla oblongata
- reticular formation
What is the thalamus composed of?
- 15 subnuclei
What is the function of the thalamus?
- all sensory information (except olfactory) relays here
- “gateway to cortex”
- sensory processing
- moor processing
- integrative functions
- motivation
- memory
What are the functions of the hypothalamus?
- feeding: digestion and detection of nutrients
- fight: release of hormones
- flight: blood pressure and circulation
- fornication: behvioural and hormonal responses
Which areas are involved in the endocrine system and how?
- hypothalamus: controls pituitary gland
- pituitary: controls secretion of hormones from other sites in the body
- hormones: communication, slow and long-lasting messages, coordinates with neurotransmitters
What is the main function of the midbrain?
- coordinates sensory information
- “relay stations”
What are the substructures of the midbrain?
- tectum (superior colliculus and inferior colliculus)
- tegmentum
- substantia nigra
What functions involve the tectum?
- sensory processing (visual and auditory)
- produces orienting movements
What functions involve the tegmentum?
- eye and limb movements
- perception of pain
What functions involve the substantia nigra?
- voluntary movement
What is the main function of the hindbrain?
- “life support”
- breathing, heart rate
What are the key features/functions of the medulla?
- attaches to spinal cord
- unconscious functions (breathing, muscle tone, circulation)
What are the key features/functions of the pons?
- connects brainstem and cerebellum
- some sleep functions
What is the general function of the cerebellum?
- smoothing and coordinating movement
- learning complex moves so they become automatic takes place here (walking, throwing ball)
What are the key features/functions of the reticular formation?
- netlike mixture of neurons and nerve fibers
- “reticular activating system”
- stimulates the forebrain (regulation of sleep-wake behaviour and behavioural arousal)
What are the 3 lobes of the cerebellum?
- vestibulocerebellum (flocculonodular lobe)
- spinocerebellum
- neocerebellum
What are the functions of the vestibulocerebellum?
- receives a substantial amount of its input from the vestibular nerve
- important regulator of the vestibular system
- regulates balance and eye movements
What are the functions of the spinocerebellum?
- regulates body and limb movements
- important in regulating muscle tone and in adapting the body to changing circumstances
- includes vermal and paravermal zones of the anterior lobe and part of the posterior lobe
What are the functions of the neocerebellum?
- comprises most of the lateral hemispheres of the cerebellum
- receives the vast majority of its input from the pontine nuclei which receives input from the majority of the cerebral cortex via corticopontine fibers
- involved in planning movement and evaluating sensory information for action
