Neuroanatomy Lectures Flashcards
What are the major divisions of the CNS
Brain: encephalon
Forebrain (prosencephalon)
- telencephalon
- diencephalon
Midbrain (mesencephalon)
Hindbrain (rhombencphalon)
- pons
- medulla
What is the difference between between white and grey matter?
What are association, commisural and projection fibres?
What are the functions os the insula and opercula?
Functions include disgust, emotion, homeostasis, perception, motor control, self-awareness, cognitive functioning, and interpersonal experience.
What are the functions of the frontal lobe?
Motor function, problem solving, memory, judgement, impulse control, higher cognitive function, language, executive function.
What are the functions for the temporal lobe?
Semantic processing (the meaning and identity of things), memory, Language, primary auditory cortex.
What are the functions for the parietal lobe?
Somatosensory,
Dominant (usually left) perception, language and mathematics
Non dominant (usually right): visuospatial function
What is the occipital lobe like?
Visual
Stria of Gennari/striate cortex
What is teh neocortex like?
6 layers
Input from other cortical areas
Projects to thalamus and input from thalamus
Projects to brainstem and spinal cord
Projects to thalamus
What are brodmanns areas?
What is the brains asymmetry dominance?
What is the brocas, wernickes areas and the corpus callosum?
What are the coverings of the brain?
Skin -
Bone
Dura mater -
Arachnoid mater -
Trabeculae
Subarachnoid space
Pia mater -
Cerebral cortex -
Blood vessel-
White matter
What does dura mater involve?
Falx cerebri
Tentorium cerebelli
Tentorial incisure
Straight sinus
Inferior sagittal sinus
Superior sagittal sinus
Transverse sinuses
Falx cerebelli
What is arachnoid mater and cisterns like?
What are the 4 key elements for the blood brain barrier?
Endothelial cell tight junctions
2.Lack of BM fenestrations
3.Astrocytic end feet
4.Pericytes
What is the circle of Willis made up of/
What are the superficial veins and sinuses of the brain?
-Superior sagittal sinus
- Inferior sagittal sinus
- Great cerebral vein
- Straight sinus
- Confluence of the sinuses
- Superior anastomotic vein
- Superficial middle cerebral vein
- Inferior anastomotic vein
- Internal jugular vein
-Superior sagittal sinus
- Confluence of the sinuses
-Transverse sinus
- Sigmoid sinus
What is the vasculatur of the spinal cord?
What is the ventricular system?
- Lateral ventricles (I & II)
- IIIrd ventricle
- IVth ventricle
- Cerebral aqueduct/ aqueduct of Sylvius
- Interventricular foramen
What are the imp ependymal cells and choroid plexus?
What is the interstitial fluid drainage?
Interstitial fluid drains → CSF via perivascular channels.
•CSF drains via
•arachnoid granulations
•peripheral nerves to lymphatics
•Importantly: nasal mucosa lymphatics → deep cervical lymph nodes
What does the brainstem give rise to?
Cranial nerves
What are the cerebellum divisions?
Archicerebellum (oldest) floculonodular lobe:
○balance. Connected to vesibular nuclei and reticular nuclei.
●Paleocerebellum (quite old):
○Muscle tone and posture
○Afferent: dorsal spinocerebellar tracts via inf cerebellar peduncle and ventral SC tract via superior CP
○Efferent: Globose and emboliform nuclei to red nucleus to rubrospinal tract
●Neo cerebellum (more fancy movements, coordination, muscle tone)
○Afferent: Cerebral cortex to pontocerebellar fibres (decussate) via MCP
○Efferent: Purks to dentate to red nucleus & ventral thalamus via SCP
What is the cerebellar wiring like?
Mossy fibres from cortex (ponto cerebellar pathway), vestibular nucleus, spinal cord, reticular formation, deep cerebellar nuclei (feedback)
What are the three main groups of nuclei in the thalamus?
3 main groups of nuclei:
●sensory relays
●cerebellar and basal ganglia relays to motor frontal lobe
●connected to associative and limbic areas of cerebral cortex
Damage causes loss of sensation, pain, or movement disorders
What are the thalamic connections?
Input from mamillary bodies.
Controls emotional aspects of behaviour, instictive drives, memory
Etc
What is the basal ganglia and internal capsule structure like?
What is anterolateral cordotomy?
Now usually done percutaneously
•For treatment of intractable pain.
•Side effects include sleep apnoea due to reticulospinal tract damage
What is the spinothalmic tract like?
Crude touch,
Pain
Temperature
What is the DC medial leminscus pathway like with Vibration
Joint position?
Is the corticospinal pyramidal tract involved in movement?
Movement
GO THrough IMAGES ON NEUROANATOMY LECTURE - LEARN AND LABEL
What are the basal ganglia?
Deep brain structures first described
by Thomas Willis
•Two subgroups:
Rostral (upper part)
1. Striatum
•Putamen
•Caudate nucleus
- Globus pallidus
•Internal segment (Gpi)
•External segment (Gpe)
–Subthalamic nucleus
–Substantia nigra
Caudal (lower part)
Where is the caudate nucleus?
runs along the wall of the lateral ventricles
The putamen is lateral to the caudate nucleus
Caudate and putamen together form the striatum
Where is the substantia nigra?
The substantia nigra is in the mesencephalon
The red nucleus is above the substantia nigra
The subthalamic nucleus is rostrolateral to the substantia nigra
What circuits are basal ganglia involved in?
Several different circuits
–Motor circuit
–Limbic circuit
–Oculomotor circuit
What illnesses are associated with basal ganglia dysfunction?
Illnesses associated with Basal Ganglia dysfunction:
–Parkinson’s Disease
–Huntington’s Disease Motor
–Dystonia Disorders
–Gilles de la Tourette syndrome
–Obsessive compulsive disorder Psychiatric
–Attention Deficit Hyperactivity Disorder (ADHD) Disorders
–Cerebral Palsy Secondary
–Wilson Disease Damage
What is the role of dopamine in PD and HD?
PD
–Increased muscle tone
–Reduced movements
–Not enough dopamine
•HD
–Decreased muscle tone
–Overshooting movements
–Too much dopamine
What is the role of dopamine in PD and HD?
PD
–Increased muscle tone
–Reduced movements
–Not enough dopamine
•HD
–Decreased muscle tone
–Overshooting movements
–Too much dopamine
What is the synthesis and vesicular storage of dopamine?
Synthesis and vesicular storage
Tyrosine - amino acid
L-DOPA
Dopamine
What is DA - Postsynaptic?
What else is involved in the DA system?
What happens to the head of caudate in HD?
What is the function of the cortex and basal ganglia?
“Will power” and motor execution
Basal ganglia:
Facilitation, integration
“fine tuning of movements”
What is involved in generating movement?
Cortex -> basal ganglia
-(substantia nigra - dopamine +/Striatum-GABA - )->
cortex -> movement
How does movement pathway get affected by PD and HD?
PD no substantia nigra releasing dopamine
Decrease in movement?
HD no Striatum releasing GABA - increase in movement
What is L-DOPA?
Naturally occuring precursor and drug
What is the drug treatment of DP?
Drugs mostly aim at correction of dopamine deficit
•But:
–More and more cells die
–The drugs work shorter and shorter
–The longer on treatment, the more likely are the patients to develop side effects, in particular dyskinesias
How does stimulation affect PD?
Stimulation = Functional lesioning of the subthalamic
Nucleus leads to dramatic improvement of PD
HOW? PATWHAY?
What is the regional pattern in the brain in HD?
What is the Pharmacological treatment of choreiform movements?
Problem: Too much dopamine
•Solution: Dopamine receptor blockers = neuroleptics
–Typically used for psychosis treatment
