FUNCTIONAL-NEUROANATOMY.pdf

🤯 Functional Neuroanatomy Class NEU 212 Type PRELIM Lesson 4 I. Meninges Additional protection for the brain. Non nervous connective tissue Contains the...

🤯 Functional Neuroanatomy Class NEU 212 Type PRELIM Lesson 4 I. Meninges Additional protection for the brain. Non nervous connective tissue Contains the CSF It makes the brain float. When the brain doesn’t float, affected agad ang brain mo. There are 3 meninges (DAP) Dura Mater Toughest and outermost layer, also called the Pachymenix Dura = tough, In the process of a traumatic brain injury, the dura matter needs to be penetrated for it to be called a TBI. The brain folds because of the Dura. Subdural Space: The space between the dura mater and arachnoid is the subdural space. (These spaces protect the brain from associated hemmorhagic injury) Arachnoid The middle layer It houses the CSF and acts as a cushion Subarachnoid space: The space between the arachnoid and pia mater is the subarachnoid space. This space ends in sacral 2 and 3 of the spinal chord. This is also the space for spinal tapping. (Spinal tapping is used for diagnosing brain viruses, etc.) LOCATION FOR THE FLOW OF CSF. Pia Mater It fuses with the ependyma to form the choroid plexus The choroid plexus is the one that produces CSF. II. Ventricles and Cerebrospinalfluid 3 main ventricles: “brain cavities”. It helps lessen the weight of the head. Filled with CSF so that the brain doesnt grow. Lateral Ventricle (Left and right) (Most superior) 3rd Ventricle (Near brain stem) 4th Ventricle (Inferior CSF Function (PINCH) Protection It lessens the force applied in the brain The neuroglia in the CSF helps with the detection of foreign substances Removal of foreign substances Intracranial pressure regulation Kapag maraming CSF, tataas ung intercranial pressure which is detrimental for the brain. Hydrocephalus is an abnormal increase of the intercranial pressure Nutrition mode of transportation of nutrition to the brain Cusion due to buoyancy Functional Neuroanatomy 1  Homeostasis CSF Flow Produced in the choroid plexus of the lateral ventricles. Moves to the two lateral ventricles Flow to the interventricular foramina or the foramen of monroe Moves into the third ventricle Another choroid plexus located in the third ventricle produces more CSF It will then move to the aqueduct of sylvius It will arrive to the 4th ventricle Another choroid plexus in the 4th ventricle will produce more CSF It will then flow to the openings or apertures. Two lateral and one medial. The medial is called Foramen of magendie and the lateral is called foramen of luschka. It will then arrive to the subarachnoid space. It will start in the Sacral 2 and 3 of the Spinal Cord Distribute to the external surfaces of the brain and spinal cord It will then drain in the arachnoid villi and then move the draining vessels in the superior sagitttal sinus The CSF will go to the blood and then weewee mo na palabas hehehe III. Circle of Willis Blood supply of the brain IV. Neurophysiology 🧠 General Organization of the Nervous System Focus on the glial eells V. Cerebrum The cerebrum is the largest part of the brain. It consists of two large hemispheres (left and right hemispheres) Left (Dominant) MALI Right (Nondominant) HAM It occupies the anterior and middle cranial fossae and the superantorial region of postrior cranial fossa. Contralateral functions: left controls right and vice versa Each hemisphere consists of a surface layer of gray matter, called the cerebral cortex and a central core of white matter. In the basal part of the latter are located large masses of gray matter, known as basal nuclei/ganglia Gyri and Sulcus Gyri/gyrus: These are elevated ridges of tissue on the surface of the cerebral hemisphere. (the hills) Sulci/sulcus: Shallow grooves separating the gyri. (the canyons) Fissures: Deeper grooves which separate large regions of the brain. The more prominent sulci and gyri are important anatomical landmarks. Median Longitudinal Fissure: separates the right and left cerebral hemisphere. Transverse Cerebral Fissure: separated the cerebral hemisphere from the cerebellum. Central Sulcus or Rolandic Sulcus: lies in the frontal plane, separates the frontal lobe from the parietal lobe Precentral Gyrus: anterior border of the central sulcus Postcentral Gyrus: posterior border of the central sulcus Parieto-occipital sulcus: separates the parietal from the occipital lobes Lateral sulcus: separates it the temporal lobe from the parietal and frontal lobe. Functional Neuroanatomy 2  Fiber Connections: Commissural fibers: Connects left and right structure Corpus Callosum: connect left and right hemisphere Association Fibers COnnects structures within the same hemisphere Arcuate Fasciculus: connects the wernickes area to the broca’s area. If you have a lesion here you have conduction aphasia (repetition). Projection Fibers Connects structures outside the brain mga tracts (corticospinal tracts) The brain has 5 lobes: 1. Frontal 2. Parietal 3. Temporal 4. Occipital 5. Insula: buried deep within the lateral sulcus and forms part of its floor it is covered by portions Each cerebral hemisphere has three basic regions Superficial cortex of gray matter: looks gray in fresh brain tissue Internal white matter Basal nuclei: Islands of gray matter situated deep within the white matter The cerebral cortex is where our conscious mind is found. It enables us to be aware of ourselves and our sensations, to communicate, remember, and understand, and to initiate voluntary movements. Brodmann Areas (not complete pa, just refer to the pdf for this one) Cerebral cortex is identified ito 52 cortical areas called Brodmann areas. Brodmann Area Neuroanatomy Functions Pre central gyrus, primary 4 Primary motor area flacidity (weak motor cortex Precentral Gyrus (including 6 premotor or supplemental motor cortex Spasticity supplementary motor area) 9-12 Prefontal area Higher cortical functions (judgement) Behavioral problems Functional Neuroanatomy 3  Brodmann Area Neuroanatomy Functions facilitates eye movement and visual 8 Frontal cortex reflexes as well as pupil dilation and eye movement constriction. Brocas aphasia, motor aphasia, 44,45 Broca’s area Production of speech expressive aphasia, nonfluent aphasia. Post central gyrus, primary receiving sensory Hemianesthesia (lack of sensation on 1,2,3 somatosensory cortex information one side of the body) kapag diniinan mo ung pag touch sa Superior parietal lobule. Interprets the Gersmann 5,7 both hands, di nila alam kung saan ung association sensory information Syndrome diin Gersmann 39 Angular Gyrus Visual Interpretation Syndrome 40 Supramarginal gyrus idiomotor apraxia 43 Primary gustatory cortex taste Ageusia: loss of taste VI. Basal Ganglia: The Basal Ganglia monitors the intensity of movement, motion, it directly affects the production of neurotransmitters. Neurotransmitters: either excitatory or inhibitory Acetylcholine: neuromuscular junctions Norepinephrine: Sympathetic nervous system Dopamine: Motivation and mood Glycine: GABA: inhibition in the brain The most abundant neurotransmitter in the nervous system is glutamate The most abundant neurotransmitter in the cerebral cortex is GABA The most abundant neurotransmitter in the spinal cord is Glycine It also smoothens muscle performance The most abundant neurotransmitter in the striatum is Dopamine Structural organization Corpus Striatum Centriform Putamen Globus Palibus Neostriatum Putamen caudate nucleus Functional Organization Subthalamus Subthalamic nucleus Substantia Nigra Pars compacta Produces dopamine In parkinsons disease, the dopamine levels drop. Pars reticulata Produces GABA Functional Neuroanatomy 4  VII. Diencephalon It has four subparts Subthalamus Motor control Hypothalamus Suprachiasmatic nucleus Sleep-wake cycle or Circadian Rhythym Preoptic Nucleus Sex drive Lateral Hypothalamus Hunger centre Medial Hypothalamus Satiety Anterior hypothalamus Labas init (sweat) Posterior hypothalamus Pasok init (shivering) Epithalamus Hanibular Nuclei Olfaction Pineal body Induces sleep Melatonin excretion Thalamus Sensory relay except olfaction. All sensory input except olfaction. VIII. Cerebellum “the little brain” Ipsilateral functions: left controls left and right controls right It has 3 lobes Anterior Lobe Called Paleocerebellum Responsible for muscle tone You can become flacid or have hypotonicity Posterior Lobe Neocerebellum Coordination Flocullonodular lobe Archicerebellum Balance Vermis Maintains upright posture Arbor VItae Tree of life maintains respiration A lesion in the cerebellum give you Ataxic Dysarthia Scanning speech Naninigas pag nagsasalita Functional Neuroanatomy 5  Limbs have incoordination lost of balance IX. Brainstem It has three structures: Midbrain It bridges all the tracts from the basal ganglia The reflex center of the brain Visual reflex located in the superior folliculi of the midbrain Hearing reflex Located in the inferior folliculi of the midbrain The cranial nerves 9-12 are seen here Motor control Pons The cranial nerves 5-8 are seen here Bridges the left and right cerebellum Sleep, respiration, swallowing, etc. Vaso motor control regulation of inspiration Parts Upper pons Pnemotaxic center inhibits insipration Lower pons Apneustic center inspiration Nagstistimulate ng inspiration Medulla Oblangata The cranial nerves 3-4 are seen here Vasomotor center Houses automatic respiratory reflects center Junction between the spinal cord to the foramen magnum X. Spinal Cord This starts at the foramen magnum and connected by the medulla oblangata It ends at Adults = L1 Children = L3 Conus Medularis This is where the spinal cord tapers off. Filum Terminale Pia matter prolongation Where the CSF produces in the spinal cord The length of the spinal cord differs in gender Male = 48 cm Female = 45 cm The cervical area or cervical spinal cord branches off to the brachial plexus. The lumbar are branches off to the lumbosacral plexus. Central Part Functional Neuroanatomy 6  Grey matter Peripheral part White matter Functions: Anterior part Motor Posterior part Sensory VEM - DAS Ventral - Epherent - Motor Dorsal - Afferent - Sensory Functional Neuroanatomy 7