Central Nervous System PDF

Central Nervous System (CNS) – Part I Objectives of the CNS Section CNS Functional Anatomy (Brain & Spinal Cord) √ CNS Function (Sensory & Motor) CNS Neurotransmitters Higher Functions (learning & memory, language, sleep, motivation & emotion) CNS Disorders  Outline of the Material Ner...

Central Nervous System (CNS) – Part I Objectives of the CNS Section CNS Functional Anatomy (Brain & Spinal Cord) √ CNS Function (Sensory & Motor) CNS Neurotransmitters Higher Functions (learning & memory, language, sleep, motivation & emotion) CNS Disorders  Outline of the Material Nervous Spinal Brain CNS System Cord CNS Motor Functional Sensory (Quick Functional Functions Anatomy Functions Intro) Anatomy CNS Neuro- Learning & Language Motivation CNS transmitte Memory Sleep & Emotion Disorders rs Today’s Outline Nervous Brain Spinal Cord System (Quick Functional Functional Intro) Anatomy Anatomy  By the end of this session, you will be able to: 1. Identify the main structures of the Today’s human brain and discuss their function Learning Objectives 2. Identify protective elements of the CNS and discuss their role 3. Describe spinal cord functional anatomy, spinal tracts and the effects of spinal cord injury Recommended Video to Watch (Not Testable): https://www.youtube.com/watch?app=desktop&v=4 4B0ms3XPKU Nervous System Nervous system has two major divisions: Central nervous system (CNS), composed of the brain and spinal cord Peripheral nervous system (PNS), consisting of nerves that connect CNS to peripheral structures Nervous System – Neurons (1) Two major cell types found in the nervous system: main unit of Neuron: functional nervous system, generates electrical signals (action potentials) supportiveofthe neuron Glial cells: non neuronal cells that support neurons (do NOT) generate nerve impulses nopotential ? Illustration of a typical neuron created Neuronal synapse Nervous System – Neurons (2) Lie entirely within the CNS & account for >99% of all neurons If : most of the axon is in the PNS goes down Nervous System – Glial Cells Neuron Astrocyte Oligodendrocyte 1. Astrocytes supply nutrients for neurons 2. Oligodendrocytes myelin formation 3. Ependymal cells make CSF cell.in 4. Microglia immune the CNS Yiiai Myelin What about Schwann cells ?! CSF Glial cells that are a part of PNS Ependymal cells Microglia Do You Remember (from nerve & muscle section) ?! ❖ Which of the following participate in forming the myelin sheaths for the axons in the CNS? A. Neurons B. Schwann cells in the PNS C. Astrocytes D. Oligodendrocytes in the CNS E. Ependymal cells Central Nervous System: The Brain Lateral View of the Skull and Brain cranial centiicus bones O 0 O O EEEITiiiio.se Overview of Planes and Directions (1) EYE crown Brainis 3 D structure Roller Coaster Discount Voucher (rostral, caudal, dorsal, ventral) Overview of Planes and Directions (2) obtain The cerebellum is …….. to the spinal cord! rostral spinal cord Foundations of Neuroscience Copyright © 2021 by Casey Henley Major divisions of Human Brain (Sagittal Section) Forebrain Midbrain Hindbrain Cerebrum Midbrain Cerebellum Diencephalon Pons Corpus Medulla Oblongata Callosum connect tall the lobes Themthphere of thfain Brainstem Diencephalon (Sagittal Section) busstation sleep Copyright © 2019, 2016, 2013 Pearson Education, Inc. All Rights Reserved  Brain Stem (Lateral View) Icerebelium midbrain polns pont optictract medulla breathing cardiovomiting insideponstrommetakia anesthesiawillaffect thisareafast Copyright © 2019, 2016, 2013 Pearson Education, Inc. All Rights Reserved Parts of Cerebrum & Diencephalon (Frontal Section) Outer shell of gray matter has composed of cell bodies EMBiates (give the area a gray WhEmatter appearance) 1content Inner layer of white matter 35ᵗʰ composed of tracts of myelinated axons has egg What do you think ?! Which are associated with gray matter? A. myelinated axons B. neuronal cell bodies C. signals carried up and down the spinal cord D. nuclei in the brain E. Both B and D Copyright © 2019, 2016, 2013 Pearson Education, Inc. All Rights Reserved Major Structures of the Limbic System Cingulate gyrus inemotional Structures of the limbic system tonÉh behaviour are associated with Septum Learning/memory Emotion ? Sex JEFE Visceral function (Appetite) homeostasis meetings Endocrine function funny smell can Amygdala bring back memories center ofemotion  Summary of Functions of Major Parts of the Brain Cerebral Participates in perception, generation of skilled cortex movements, and cognitive functions (reasoning, learning, and memory) Basal ganglia higherlevelfunc Participate in the initiation of movement and coordination of skeletal muscle activity hand waving example Thalamus Acts as a synaptic relay station for sensory pathways on their way to the cerebral cortex; also participates in control of skeletal muscle coordination, and has a key function in awareness Hypothalamus Participate in temperature control, water balance, eating and drinking behavior, and emotional behavior, also homeostasis regulates the reproductive system and circadian rhythms Cerebellum Coordinates movements, such as eye movement and those for posture and balance. Participates in some forms of spiralFord learning Brainstem 1. Cardiovascular, respiratory, digestive control 2. Sleep/wake cycle, arousal 3. Balance and posture 4. Locomotor initiating centre Spinal cord Locomotor pattern generator (producing rhythmic movements), spinal reflexes movement  7 temporal Practice Major Structures of the Brain and Their Function ! fright pariet thalamus hypothal Pituatgand midbrain cost X pineal pons cerebellum medulla oblongata 19 SP Protective Elements Associated with the CNS Bone Skull for the brain Vertebrae for the spinal cord outside Meninges composed of 3layers Dura mater Arachnoid mater knowthe D Pia mater arrangement PADforthe brain Cerebrospinal fluid (CSF) Cushions the structures insubarachnoid region Blood-Brain Barrier (BBB) inside Helps maintain a stable environment for the brain  Hydrocephalus?! insubarittle tpQ.mn chCS ependynemal cellsusuallydrains createwitha balance Jangge orangeare ependyemal cells Blood-Brain Barrier (BBB) notphysical morechemicalprotectant ❖ The BBB closely controls the types of substances that enter the brain extracellular fluid and the rates at which they enter ain hartnee Eiiiin.tr state What do you think ?! Neural tissue has minimal extracellular matrix. Which is involved in the support and protection of neural tissue? A. Cerebrospinal fluid B. Meninges C. Glial cells D. Outer casing of bone E. All of the above Copyright © 2019, 2016, 2013 Pearson Education, Inc. All Rights Reserved Central Nervous System: The Spinal Cord Lateral View of the Spinal Cord 31 spinal nerves convey signals to and from the spinal cord: 8 cervical 12 thoracic 5 lumbar Inotuthber 5 sacral 1 coccygeal 8am 12pm 5pm viewfrom theside 5am I coffee Dermatomes C1 2 know which are asthey innervate Cervical 3 4 Head, neck, shoulders, arm, hand C1-C8 5 6 ✓ Each spinal nerve 7 8 T1 C2 innervates a specific 2 3 C3 area of skin 4 5 C2 C3 C4 C4 T3 (Dermatome) and a Thoracic 6 C4 T2 T4 T5 T6 Trunk T3 C6 C7 T1-T12 7 T7 T4 C5 C8 C5 T8 specific set of T5 T2 T2 C5 8 T1 T6 T1 T9 T7 T10 T1 9 T11 T8 muscles (Myotome). C6 C6 T1 T12 10 C6 T9 L1 C7 T10 11 T1 T11 C7 T1 S2 T12 S5 12 C8 C8 L2 Co L1 S3 C6 S4 L1 Lumbar S3 C8 2 Waist, front of L2 S4 L2 L1-L5 S3 L2 C7 3 4 legs, feet L3 L3 5 L3 S2 S2 Sacral Buttocks, L4 L4 S1-S5 and genitals, anus, L4 L4 L5 Coccygeal back of legs, feet S1 S1 S1 L5 L5 L5 S1 S1 L5 Primary Roles of the Spinal Cord orderisswitchedthanin brain Send sensory information from the body to O the brain (dorsal root) O Send motor commands from the brain to the O body (ventral root) O Coordinate reflexes (acting without signals from the brain) withoutthinking doesn'tgoto brain Also contains central pattern generators that control rhythmic movements (walking, flying, swallowing, etc.) primarily initiated by this Copyright © 2019, 2016, 2013 Pearson Education, Inc. All Rights Reserved Section of the Spinal Cord (Ventral View) Afferent neuron axons that enter the spinal cord from peripheral nerves enter on the dorsal side of the cord via the dorsal roots. Dorsalonly _accumulated root ganglia, contain the cellbodies cell bodies of these afferent neurons. The axons of efferent neurons leave the spinal cord on the ventral side via the ventral roots. noventral root  9 Further Organization of the Spinal Cord sensory motornuclei hom gray tract axons aftergatiending Multie pathway tract hochbination ofnuclei Copyright © 2019, 2016, 2013 Pearson Education, Inc. All Rights Reserved destending tract  Spinal Reflexes getssenttothe brainforexperience learning ie hotstove YÉanglia 1 process integrated in thespinalcord Copyright © 2019, 2016, 2013 Pearson Education, Inc. All Rights Reserved  intact Spinal Cord Injury (1) C1 2 Breathing (C1-4), head & neck movements (C2) 3 4 Heart rate (C4-6), shoulder movements (C5) Wrist & elbow movements (C6-7) When spinal cord is damaged at a 5 6 7 given level, sensation from and 8 T1 Hand & finger movements (C7-T1) 2 the motor control of functions 3 4 Injury at C6-7 below that level are likely to be 5 6 Blood pressure, breathing, coughing, abnormal. 7 8 control of trunk posture 9 Affected mostcommon in males 10 by injury 1 11 12 L1 Sex reflexes, hip movements, locomotion injury will 2 3 Knee movements occurto function 4 5 Knee & foot movements underneaththe injury Bladder, bowel control, sexual function  don'tneedtomemorize genevaliz Spinal Cord Injury (2) C1 2 Breathing (C1-4), head & neck movements (C2) 3 4 Heart rate (C4-6), shoulder movements (C5) Wrist & elbow movements (C6-7) Another example: 5 6 7 8 T1 Hand & finger movements (C7-T1) If spinal cord is damaged at L2, 2 3 sensation and movements of 4 5 lower part of leg, bladder, bowel 6 7 Blood pressure, breathing, coughing, and sexual functions are affected, 8 9 control of trunk posture but not breathing, trunk posture, 10 etc. 11 12 Injury at L1-L2 L1 Sex reflexes, hip movements, locomotion thelowertheinjury 2 the better Knee movements 3 4 5 Affected Knee & foot movements by injury Bladder, bowel control, sexual function Spinal Cord Injury (3) Brown-Sequard Syndrome ▪ Injury is on one side of the spinal cord (left or right) ▪ Injured side is more affected mostly butthe otherside willaffected Below the lesion a well ontheotherside spiathway onsameside Shams and Arain, 2022. Image courtesy S Bhimji MD Answer me ! Which is TRUE? A. Descending tracts carry efferent signals. B. Ascending tracts carry sensory information. C. Dorsal roots carry sensory information. D. Ventral roots carry efferent signals. E. All of these statements are true. Copyright © 2019, 2016, 2013 Pearson Education, Inc. All Rights Reserved Quick Summary Main structures of the human brain and their function Protective elements of the CNS (glia, bone, meninges, CSF, BBB) Spinal cord functional anatomy Spinal tracts and spinal cord injury Images from: Graphics, Vectors, and animations from: freepik.com (Copyright © 2010- 2023 Freepik Company S.L. All rights reserved) vecteezy.com (© 2023 Eezy Inc. All rights reserved) under Free License. © McGraw Hill, LLC. All rights Copyright © 2019, 2016, 2013 and tenor.com reserved. Authorized only for Pearson Education, Inc. All instructor use in the classroom. Rights Reserved. CNS and Spinal Cord Rap (1) i Yo, let's dive deep into the neural sea, Temporal lobe, for memory and sound, Where synapses fire, wild and free. Where language is processed, profound. The CNS, a intricate machine, Occipital lobe, for vision's delight, A symphony of neurons, unseen. Interpreting images, day and night. Cerebrum, the cortex, a layered expanse, Where thoughts and emotions entwine and dance. Frontal lobe, the executive suite, Planning, decision-making, a complex feat. Parietal lobe, for spatial awareness, Integrating senses, a neural caress. CNS and Spinal Cord Rap (2) Cerebrum, the balance maestro, Spinal cord, a highway of nerves, Coordinating movements, a rhythmic show. Connecting brain to body, it never swerves. Brainstem, the vital center, Gray matter, where neurons reside, Regulating functions, a life-sustaining splendor. White matter, the pathways, where signals glide. Medulla oblongata, heart and breath, Reflexes, quick responses, a survival tool, Pons, sleep and arousal, a delicate death. Bypassing the brain, a neural rule. Midbrain, for motor function, And sensory processing, a neural junction. Central Nervous System (CNS) – Part II Objectives of The CNS Section CNS Functional Anatomy (Brain & Spinal Cord) CNS Function (Sensory & Motor) √ CNS Neurotransmitters √ Higher Functions (learning & memory, language, sleep, motivation & emotion) CNS Disorders Outline of Today’s Material CNS Sensory CNS Motor Function Function CNS Neuro- transmitters  By the end of this session, you will be able to: Today’s 1. Identify sensory, motor, and association Learning areas of the brain and their pathways Objectives 2. Identify major neurotransmitters and neuromodulators in the CNS and their receptors, and describe their functions Brain Function the From a functional viewpoint, brain can be divided into three specializations: 1) Sensory areas 2) Motor areas 3) Association areas in between Primary Motor Cortex (motor cortex) Integrate information from sensory and Primary Somatosensory Cortex motor areas (sensory cortex) Association Areas motor cortex Motor association area Sensory association area 5 major ones senatex Prefrontal association area prefront tex Auditory association area Visual association area auditorycortex visualcortex  Demonize his Sensory Information – A Few Points ❖ Most sensory information travels from the body to the brain along ascending pathways in the spinal cord OR from the head to the brain via cranial nerves afferentneuron sameinfoboan brain some interah Gentebrain autumnghospinal ❖ Some information does not reach the brain, e.g., cord visceral reflexes are integrated in brainstem or spinal cord and usually do not reach conscious perception (e.g., control of blood pressure) some sensory info nevergetto brain reflexed Sensory Information (2) ❖ Processing does not end in primary receiving areas but continues to association areas for further complex processing/integration. O smelldoesnotgo tothethalamus soma body Somatosensory Cortex – Somatotopic Map note Filmation a lot of sensory 00 into associated in 0 Qeñfrize  Somatic Senses – Ascending Pathways differentfeeling will take perieption ofbody t.hnfh diff ▪ Touch typeof pathways ▪ Proprioception neuron ▪ Temperature ▪ Nociception ▪ Pain ▪ Itch EE L Figure 10-8 (silverthorn) crosselthespinalcord  p l y p p Motor Information – Motor Cortex r o A large number of neurons in the “descending” pathways for motor control come from the primary motor cortex and the premotor Edelinated area. gritemient o Neurons of the motor cortex that control muscle groups in various parts of the body are arranged into a somatotopic map (similar to that seen in the somatosensory goingtowards cortex). EEE Factions Somatotopic Map of Primary Motor Cortex hermoncums part ththStor IFEments neyelded Descending Pathways starts atcortex tospinal footfsiteside 1. Corticospinal/pyramidal pathways originate in the cerebral cortex control rapid, fine movements of the distal extremities distal limb furtherfromtheaxis of 2. Brainstem/extrapyramidal system they pathways originate in the brainstem involved with coordination of the large muscle groups of the trunk and proximal SMITE portions of the limbs Let’s Put Everything Together ! motor sensory EFEed neuron ❖ How do these neurons communicate with each other? ✓ We will discuss it in the next section (neurotransmitters) What Do You Think ?! Ascending sensory pathways A. Cross the midline in the spinal cord. B. Cross the midline in the brainstem. C. Cross the midline in the medulla. D. They do not cross the midline. incorrect E. A, B, and C crossoverin medulla 1 in brainstem which are in the midline Copyright © 2019, 2016, 2013 Pearson Education, Inc. All Rights Reserved Neurotransmitters Quick Overview of the Synapses neurot ansmitters attached ftp.reibpcneqtic Electrical synapse Chemical synapse Mechanisms of Signaling at a Chemical Synapse Depolarization during the action potential opens voltage-gated calcium channels at the axon terminal Calcium entry activate processes that lead to the fusion of docked vesicles with the synaptic terminal membrane, leading to the release of neurotransmitters Activation of the Postsynaptic Cell at a Chemical Synapse Excitatory Postsynaptic Potential yet y ome Est c qieieit.IT neuon Inhibitory Postsynaptic Potential  Some Classes of Neurotransmitters or Neuromodulators √ Acetylcholine (ACh) Biogenic amines Catecholamines Dopamine (DA) √ Norepinephrine (NE) FOCUSonthis Epinephrine (Epi) Serotonin (5-hydroxytryptamine, 5-HT) Histamine Amino acids √ Excitatory amino acids; for example, glutamate Inhibitory amino acids; for example, gamma-aminobutyric acid (GABA) and glycine Neuropeptides For example, endogenous opioids, oxytocin, tachykinins Gases For example, nitric oxide, carbon monoxide, hydrogen sulfide Purines For example, adenosine and ATP Lipids For example, prostaglandins and endocannabinoids Neurotransmitters vs. Neuromodulators Neurotransmitters can act at neuro involved in “rapid” communicationMeffectis very fast Neuromodulators can act as neurotrans associated with “slower” events (e.g., learning, development, etc.) occur over minutes, hours, or even days can modify (amplify or dampen) postsynaptic cell’s response to specific neurotransmitters canincrease ordecreaseits activity Acetylcholine (ACh): A Major Neurotransmitter Neurons that release ACh: Cholinergic neurons FOCUSEDONCNS Receptors: muscarinic (G protein-coupled) or nicotinic (ligand-gated ion channel) Muscarinic receptors in the brain: involved in higher cognitive processes (learning and memory) Nicotinic receptors in the brain: important in reward pathways (nicotine/tobacco addiction) Nicotinic vs. Muscarinic ACh Receptor inthe periphffion Nicotinic: Fast EPSP acetate Muscarinic: s Slow EPSP 5 glebinka nicotinic ftp.tors muscarinic I mutttimore 9,9hachannels lactivategia more and ctklfefsia.ch more tobindto channel Biogenic Amines Small molecules synthesized from amino acids Most common neurotransmitters are: Dopamine (involved in brain reward systems and motivation) Norepinephrine (noradrenaline) allointhe periphery Serotonin epinephrine notimportantin alertness theens Epinephrine (adrenaline) is not common in CNS Norepinephrine is important in CNS (alertness, attention, cognitive function, stress reactions such as anxiety) ✓ Adrenergic receptors (Alpha & Beta) 321213 ✓ Excitatory and inhibitory effects anxietyrelated highernorepinephrine Serotonin (5-HT) everywhere in brain spinal cord ❑ A neuromodulator at every structure in brain and spinal cord ❑ 16 different receptor subtypes (G-protein or ligand gated) ❑ Excitatory or inhibitory effects ❑ Regulate food intake, reproductive behavior, emotion (mood, anxiety) low level can lead to depression ❑ Selective serotonin reuptake inhibitors (SSRI): treatment of depression activated ftp.tothfilfoftntagallowsittoaitivatethe ❑ LSD stimulates brain 5-HT2A receptor: visual hallucinations lots acid Diethylamide Lysergic I act like serotonin Amino Acid Neurotransmitters very important Most common in CNS (affect all neurons) Glutamate: Excitatory ▪ 50% of excitatory synapses in CNS Chmon ▪ Receptors: ionotropic (cation selective - the vast majority) or metabotropic (G-protein-coupled) IMPORTANT Glycine (in spinal cord and brainstem) and GABA: Both Inhibitory Thffsimpoutan ▪ Mostly Ionotropic (Cl selective) Eini ▪ Too much: loss of consciousness and coma needa ▪ Too little: seizure the brain too active tooexcited follfftain Glutamate Receptors and Glutamatergic EPSP both knownto AMPA NMDA be fastprocesses initiother glutamate 91 bindito AMPA Ghnetasily N Tood in pepoignzg.mg hmgg.tn depolarizationrepel Huang, the Emily & mgt Stevens, Charles. to charge due(1998). Essays in biochemistry. 33. 165-78. GABA (Gamma Amino-Butyric Acid) anti anxiety ▪ Major inhibitory neurotransmitter in brain ftp.jatethe sleep reduceactivityof ▪ Small interneurons that dampen neuronal activity the brain ▪ Ethanol stimulates GABA synapses and alprazolam (Xanax) inhibits glutamate synapses: depression diazepam (Valium) of brain electrical activity GABAA: ligand-gated chloride channel; mediates fast IPSP GABAB : metabotropic, slower IPSP B metabotropic Chen et al., Acta Pharmacologica Sinica volume 40, pages571–582 (2019) Quick Summary ▪ Sensory, motor, and association areas ▪ Sensory and motor information processing and their pathways ▪ Chemical synapse, EPSPs and IPSPs ▪ Major neurotransmitters and neuromodulators in the CNS, their receptors and their function Images from: Graphics, Vectors from: freepik.com (Copyright © 2010- 2023 Freepik Company S.L. All rights reserved) and vecteezy.com (© 2023 Eezy Inc. All rights reserved) under Free License. © McGraw Hill, LLC. All rights Copyright © 2019, 2016, 2013 reserved. Authorized only for Pearson Education, Inc. All instructor use in the classroom. Rights Reserved. Central Nervous System (CNS) – Part III Objectives of The CNS Section CNS Functional Anatomy (Brain & Spinal Cord) CNS Function (Sensory & Motor) CNS Neurotransmitters Higher Functions (learning & memory, language, sleep, motivation & emotion) √ CNS Disorders Outline of Today’s Material Learning Motivation & Language Sleep & Memory Emotion  By the end of this session, you will be able to: 1. Distinguish between different classes of memory and types of amnesia Today’s 2. Explain neural basis of learning and memory Learning 3. Compare different types of aphasia Objectives 4. Distinguish between different stages of sleep based on EEG activities 5. Explain the physiology of motivation and emotion and identify the brain areas involved  Declarative (explicit) Procedural (implicit) Learning & Memory memory memory newinforesponse ofexperience Definition: Retention and Definition: Memory for recall of experiences that skilled behaviors Learning: acquisition of can be put into words independent of any information as a consequence of (declared). conscious understanding. experience. Recall needs conscious Also includes learned attention. emotional responses. Example for skilled storing info trying torecall info Example: memory of an behaviors: riding a bike, Memory: relatively permanent event (e.g., a wedding) and playing a musical storage of learned information maybe even knowing the instrument. specific time and place (ability to retain and recall when the memory Example for learned information). originated. emotional responses: fear of spiders. declarative Areas involved: Areas involved: riding a bike highexplain declare your hippocampus, amygdala, and other parts of the sensorimotor (sensory and motor) cortex, basal nuclei, limbic system and cerebellum implitit I justdo it Short-Term and Long-Term Memory Memory classification based on duration: H1 Short-term (working?) memory: seconds to minutes, and susceptible to external interference Long-term memories: days to years, and can survive disruptions BCS Short-term to long-term: basedon Consolidation i iions  Retrograde amnesia Anterograde amnesia Loss of Memory part future Short-term memory is Losing the ability to (Amnesia) interrupted when a person consolidate short-term becomes unconscious from declarative memories into retrograde pastforgotten a blow to the head, and long-term memories. past beforeaccident memories are abolished (for a variable period of time) They can remember stored difficulty for all that happened before information and events that anterograde formingmemory the blow. c occurred before their brain goingforward injury, but after the injury, they can only retain information as long as it exists in short-term memory. Cause: damage to the limbic system and associated structures, such as hippocampus, thalamus, Markowitsch and Staniloiu, Handbook of Clinical Neurology, 139, 2016, 419-445. and hypothalamus. Neural Basis of Learning and Memory One model: long-term potentiation (LTP): getstronger Certain synapses undergo a long-lasting increase in their effectiveness when they are heavily used Involves processes that alter gene expression (new protein synthesis) New proteins may be involved in increased number of synapses, increased number of transmitters or increased number of receptors on postsynaptic membrane Synaptic Plasticity  Synaptic Plasticity verystrong without repetion LTOoccurs more longterm deppretion tattletale howyouforgetthings Helepton are more sensitive splatility Eangeletter worse (Image: Alan Woodruff / Queensland Brain Institute) LTP at Glutamatergic Synapses Cooperative activity of AMPA and NMDA receptors is implicated in LTP. A process involved in learning and memory. neurotrans longtomentiation NMDA itcloseto Short LTP Video: AMPA https://www.youtube.com/watch?v=- mHgPfXHzJE membrane potential 4a membranewillrepelmg2 Match ! 1. Your memory of the World War history B A. Working memory 2. A soldier's memory of the World War experience B B. Explicit memory 3. Your ability to use the mouse on computer C C. Implicit memory 4. A person who cannot create new memories has E D. Retrograde amnesia 5. It is retrieved unconsciously C E. Anterograde amnesia Language Cerebral Dominance and Language Left hemisphere (in 90% of the population) produce and comprehend language understanding conceptualize the words (to say or write) neural control of the act of speaking or writing recent verbal memory speaking writing Males and females process language slightly differently Females: both hemispheres for some language tasks Males: mainly left side listeningtosomething emotional right hemisphere willalsobeactivated Integration of Spoken Language WHY understand Wernicke’s area: understanding language/comprehension Broca’s area: produces speech/expression Bro speech monthneurons moniiinniiii monrnemacmewem.ee go.EE 5  Aphasia Damage to languagecenter one orboth Wernicke’s area: receptive aphasia ▪ Unable to understand sensory input https://www.youtube.com/watch?v=3oef68YabD0 lastpartthat will affectthe motorcortex Broca’s area: expressive aphasia cansometimes producelanguage ▪ Unable to understand complicated sentences with multiple elements Haikage ▪ Difficulty speaking or writing normal syntax motorcortexwill innervated vellybed https://www.youtube.com/watch?v=RMa9BVpJkYQ&t=42s notbe Global aphasia: receptive + expressive https://www.youtube.com/watch?v=FUutVGeoG-k daminesen Ataxia ?! Sleep  Quick Overview of Electroencephalogram (EEG) electricalactivityofbrainneurons ✓ Measures electrical activities in the brain using electrodes attached to the scalp ✓ Diagnostic tool Nagel S. (2019). Towards a home-use BCI: 10.15496/publikation-37739. EEG Pattern During Sleep ✓ EEG pattern changes profoundly in sleep as brain activitychanges Beta rhythm (alert) 0 beta alpha ❖ As a person becomes increasingly drowsy, their wave pattern Alpha rhythm (relaxed with eyes closed) transitions from beta goingtosleep rhythm to predominantly alpha rhythm. EEG Through Various Stages of Sleep ❑ When sleep actually occurs, EEG shifts toward lower-frequency, larger-amplitude wave patterns (e.g., theta rhythm and delta rhythm) become ❑ There are two phases of sleep: increasein amplitudefrequency NREM (non-rapid eye movement) – N1, N2, N3 REM (rapid eye movement) amplitude talents NREM Sleep beta alpha theta NI N3 Three stages: Stage N1: theta waves begin to Takeshi intersperse among alpha pattern (light sleep) 30 45 reality wakeup mins Stage N2: theta waves, sleep spindles NI N3 and K complexes Stage N3: delta waves (slow-wave or deep sleep) Sleep begins with the progression from stage N1 to stage N3 (normally takes 30 to 45 minute) REM Sleep o Paradoxical sleep brain activity likebeing alert asleep is difficult to arouse but there is intense EEG activity similar to that of the alert/awake state. o Dreaming eyesmovingveryfast o REM begins 50 to 90 minute after sleep onset NI N2 N3 N2 REM first episode lasts about 10 minutes. Each of later REM episodes thisisthe sequence gets longer Nz REM does not happen NEVER ❖ If uninterrupted, sleep moves from NREM N1 to N2 to N3, then back up to N2, and then to an episode of REM  Sleep-Wakefulness Stages Stage Behavior EEG Alert wakefulness Awake, alert with eyes open. Beta rhythm (greater than 12 hertz). Relaxed wakefulness Awake, relaxed with eyes closed. Mainly alpha rhythm (8 to 12 hertz) over the parietal and occipital lobes. Changes to beta rhythm in response to internal or external stimuli. Relaxed drowsiness Fatigued, tired, or bored; eyelids may narrow and close; head may Decrease in alpha-wave amplitude and frequency start to droop; momentary lapses of attention and alertness. Sleepy but not asleep. NREM (slow-wave) sleep Stage N1 Light sleep; easily aroused by moderate stimuli or even by Alpha waves reduced in frequency, amplitude, and neck muscle jerks triggered by muscle stretch receptors percentage of time present; gaps in alpha rhythm as head nods; continuous lack of awareness. filled with theta (4 to 8 hertz) and delta (slower than 4 hertz) activity Stage N2 Further lack of sensitivity to activation and arousal. Alpha waves replaced by random waves of greater amplitude. Stage N3 Deep sleep; in stage N3, activation and arousal occur only Much theta and delta activity; progressive increase with vigorous stimulation. in amount of delta. REM (paradoxical) Greatest muscle relaxation and difficulty of arousal; E E G resembles that of alert awake state. sleep begins 50 to 90 minute after sleep onset, episodes repeated every 60 to 90 minute, each episode lasting inO2consumption about 10 minute; dreaming frequently occurs, rapid eye movements behind closed eyelids; marked increase in bythe brain brain O2 consumption. Why Do We Need Sleep? forbalance inthebody ❖ Homeostatic requirement (like food and water) notenoughsleep hungry grelinsecreted Sleep deprivation lectin secretedwith impairs the immune system dampen enough leep it causes cognitive and memory deficits won'tactaswell leads to psychosis and even death sleepallowsthe replenishment ofreceptor neurotighffithffed during sleep, brain experiences reactivation of neural pathways stimulated during the prior awake state ▪ subjects deprived of sleep show less effective memory retention braintriestotonsolidateinfo gainedthroughout theday Were you paying attention? An individual is displaying suppressed muscle tone and is difficult to wake up. When they wake up, they reports dreaming. The cycle of sleep they were experiencing is: A. Slow wave sleep B. Stage N1 C. Stage N2 D. REM sleep Motivation & Emotion Motivation & Emotion Motivation: internal signals that shape voluntary behaviors. lead to hormonal, autonomic, and behavioral responses. Emotion: results from the relationship between an individual and the environment. Internal attitudes toward events and/or environment (e.g., happiness, sadness, etc.) External responses (emotional behaviour) ie yelling atsomeone Motivation whatyouneed forsurvival I. Primary motivated behavior: directly related to homeostasis (e.g., maintaining water balance, nutrition, body temperature, etc.) pleasure II. Secondary motivated behavior: related to pleasure or addictive behaviours (over-eating, taking recreational drugs, etc.*) goingto call Tiers secondarymotivatingbehaviour ❖ Reward and punishment are inseparable from motivation high othefatitiable Brain Regions Involved in Motivation main reward pathway ✓ Mesolimbic and mesocortical dopamine pathways are parts of the reticular activating system (RAS) ✓ involved in motivation, rewards & punishments ✓ begin in the midbrain, and release dopamine in areas that process emotion givesgoodpeeing ❖ Dopamine vs. Amphetamines Eisiem groutp ofdrugs activate reward pathway dopamine release Brain Regions Involved in Emotional Responses (and motivation) Forebrain structures contentions (including cerebral cortex): modulation, direction, understanding, or even inhibition of emotional behaviors controlthis Limbic areas: inner emotions (e.g., amygdala: fear) man Lateral hypothalamus: fear emotions rage responses Prefrontal Cortex Activity During a Sad Thought (Red and Yellow Areas) the brain structure thatget activated when rad Quick Summary ❑ Classification of memory and amnesia ❑ Neuronal basis of memory (LTP–synaptic plasticity) ❑ Language and aphasia ❑ Sleep and different stages of sleep based on EEG waves ❑ Motivation and emotion and the brain areas involved in these behaviours Images from: Graphics, Vectors from: freepik.com (Copyright © 2010- 2023 Freepik Company S.L. All rights reserved) and vecteezy.com (© 2023 Eezy Inc. All rights reserved) under Free License. © McGraw Hill, LLC. All rights Copyright © 2019, 2016, 2013 reserved. Authorized only for Pearson Education, Inc. All instructor use in the classroom. Rights Reserved. Central Nervous System (CNS) – Part IV Objectives of The CNS Section CNS Functional Anatomy (Brain & Spinal Cord) CNS Function (Sensory & Motor) CNS Neurotransmitters Higher Functions (learning & memory, language, sleep, motivation & emotion) CNS Disorders √  Outline of Today’s Material CNS Disorders Amyo- trophic Multiple Alzheimer's Parkinson's Lateral Sclerosis Disease Disease Sclerosis (MS) (ALS)  By the end of this session, you will be Today’s able to: Learning Explain and discuss the pathophysiology Objectives and etiology of AD, PD, ASL, and MS while identifying their signs, symptoms and risk factors  Dementias memory loss Neurodegenerative disorders with decline in memory and other cognitive skills that reduce a person's ability to perform everyday activities pthealtmheentn.HR htit nottestable ❖ It is common to have mixed dementia (e.g., both Alzheimer’s and vascular dementia) Alzheimer’s Disease (AD) The most common cause of dementia in older adults Slowly progressive, brainshrinks characterized by neuritic plaques and neurofibrillary tangles in medial temporal d lobe and cortical structure Breijyeh and Karaman. Molecules 2020, 25, 5789. AD’s Neuropathology p levelusuallynormal in our brain 1. Senile Plaques: extracellular deposits of beta-amyloid protein (Aβ). accumulation in hippocampus, amygdala, and cerebral cortex damages axons, dendrites, and synapses 2. Neurofibrillary Tangles: tangles clumps of hyperphosphorylated tau protein accumulated in cytoplasm, axons, and dendrites geFphosphorylated overly neuron cannot communicate and will the die I7 3. Synaptic Loss: defects in axonal transport, loss of dendritic spines, pre-synaptic terminals, and axons ftp.iegn.cinqtithon Schramm Simon. (2018). License CC BY-NC 4.0 Cholinergic Hypothesis of AD ❑ ACh is involved learning, memory, attention, etc. maaven.si Eeain ❑ Β-amyloid affect cholinergic neurotransmission and cause a reduction in choline uptake and release of ACh. IEEE ❑ Degeneration of the cholinergic neurons bragley will Cholinesterase Inhibitors ? thief solution drugthat inhibits the acetylcholinesterase activity Breijyeh and Karaman. Molecules 2020, 25, 5789. AD Risk Factors ▪ Age most AD cases have a late onset (65 years and older) ▪ Genetics mutation in certain genes 70% of AD cases are related to genetic factors (mutations in amyloid precursor protein (APP), Presenilin-1 (PSEN-1), Presenilin-2 (PSEN-2), and apolipoprotein E (ApoE) ▪ Sex more common in females live longer ▪ Lifestyle sleep ▪ Medical factors important at 40 50 cardiovascular disease (CVD), obesity, diabetes ▪ Air pollutants, metals, and infections What do you think ? Which age group has the highest rate of Alzheimer cases reported? A. 85 and older B. 74 to 84 b c women livelonger C. 65 to 74 D. 55 to 65 Parkinson’s Disease Parkinson’s Disease (PD) A degenerative, progressive disorder affecting neurons in substantia nigra pars compacta (SNpc) of basal ganglia neuronswilldie off Dopaminergic neurons involved in control of body movement and muscle tone. senddopaminesignals Degeneration of these neurons in PD affects body movements. notsure what it is “Idiopathic” but a combination of genetic and environmental risk factors 60yearsold more commonin males butnotbymuch  Symptoms of PD ibisumbrella movement (Emotionless face) (Bradykinesia) nomoremuscle mtthhea.tt tseth ponceinshowiupslifelpan Symptoms of PD appear after 60-70% ofshortens Gotten dopaminergic cells in SNpc are lost, which typically occurs over 5-10 years (Akinesia) life expectancy is 15-25 years after symptoms appear movement Treatment for PD (1) ❑To increase dopamine in substantia nigra L-Dopa (precursor to dopamine) ▪ Cross the blood-brain barrier efficiacfargters EaterEaster ▪ Converts to dopamine in the brain and stimulates dopaminergic receptors 1 55off pletely ▪ Dramatic reduction of symptoms in first year but effects decline with use over the years Treatment for PD (2) ❑ Deep brain stimulation (DBS) Stimulation of different regions of basal ganglia can be effective at reducing PD symptoms and the attesting gate site DBS - Remarkable Results! Stimulation off Stimulation on Stimulation off Stimulation on motor skills state's its returned ALS * nosignal Frompetton ALS (1) neuron in the cortical pathway will die A progressive neurodegenerative disease of the upper and lower motor neurons (cortical and spinal motor neurons) Degeneration of axons within the anterior and lateral corticospinal tracts Lead to muscle weakness, atrophy, and eventually paralysis and death √ √ Most cases are sporadic (90–95%), i.e., not genetically inherited spine lower to body ALS (2) First onset of symptoms usually between the ages of 50 and 65 Most common symptoms: ▪ muscle weakness, twitching, and cramping ▪ slurred speech or trouble swallowing ▪ eventually lead to impairment of muscles (inability to do anything, swallow or breath) Risk factors: more common in males due to their occupation o Age & Sex o Smoking & Environmental toxin exposure o Physical activity (contradictory) o Radiation o Diet ALS – A Possible Molecular Mechanism – Excitotoxicity in ease Feet neurotransmitters 418 FEET TOO MUCH Cart in the postsyphatic neuron howyouki.lt the metformin the ena Spalloni et al., Biochimica et biophysica acta. 1832. Multiple Sclerosis can be in central peripheral Multiple sclerosis (MS) NOT testable in canada rate an autoimmune disease of the CNS characterized by Chronic inflammation (leading to BBB injury) Demyelination and axonal damage Astroglial proliferation (gliosis) * Neuronal loss in different CNS locations leads to severe physical or cognitive incapacitation as well as neurological problems in young adults (20 to 40 years) ✓ affects females more than males Subtypes of MS o Relapsing-remitting MS (RRMS) Most common, characterized by acute attacks followed by periods of remission. Attacks on myelin and nerve fibers occur. o Secondary-progressive MS (SPMS) Disease continues to worsen with or without remission. Many with RRMS develop SPMS (considered the second phase of the disease) o Primary-progressive MS (PPMS) Symptoms continue to worsen gradually from the beginning. No relapses or remissions. Largely affect the nerves of the spinal cord o Progressive-relapsing MS (PRMS) Least common, progressive from the start, worsening symptoms along the way. With or without remission. Subtypes of MS Treatment? Copyright © 2013 to 2023 - Epomedicine MS Etiology o Environmental factors (latitudinal gradients, season, Vitamin D deficiency) highest in North America, lowest around the equator o Genetic & racial associations heritability between 35-75% Caucasian and African American at a higher risk o Infections can leadto MS development o Diet (high in animal fat, animal products) o Toxins morecommon in females loss of vitamin D makeup MS Common Symptoms  Ronald Reagan - AD Robin Williams – PD+LBD Muhammad Ali - PD Ozzy Osbourne - PD Stephen Hawking - ALS Bryan Randall - ALS Christina Applegate - MS Jack Osbourne - MS Quick Summary Types of dementia, AD, its risk factors and pathophysiology PD signs and symptoms, pathophysiology and treatment ALS symptoms, risk factors, and mechanism MS pathophysiology, subtypes, etiology, and symptoms Images from: Graphics, Vectors from: freepik.com (Copyright © 2010- 2023 Freepik Company S.L. All rights reserved) and vecteezy.com (© 2023 Eezy Inc. All rights reserved) under Free License. © McGraw Hill, LLC. All rights Copyright © 2019, 2016, 2013 reserved. Authorized only for Pearson Education, Inc. All instructor use in the classroom. Rights Reserved.