Background (Ch 1, 3-5) - Neuropsychology PDF

Part I – Background Ch 1, 3-5 Intro to neuropsychology Brief review of Nervous system organization and function  Neuropsychology The scientific study of the relationships between brain function and behaviour Biology Biophysics Pharmacolog...

Part I – Background Ch 1, 3-5 Intro to neuropsychology Brief review of Nervous system organization and function  Neuropsychology The scientific study of the relationships between brain function and behaviour Biology Biophysics Pharmacology Physiology Chemistry Psychology Etc.  Why study neuropsychology? To gain an understanding of how the brain is organized to produce behaviour To understand human behaviour, consciousness, and diversity ↓ sexual , cultural , ete. To treat those with brain injury, disease, and neurological disorder Major divisions of the human nervous system Central Nervous Peripheral Nervous System (CNS) System (PNS) Brain Nerves that carry signals in and out of Spinal cord the CNS (vertebrates) - CNS axons i.e. spinal nerves, Retina included - due cranial nerves to developmental process-diencephalon outpocket Major divisions of the human nervous system Oconscious Sensory and motor somatosensation systems are crossed ↳ RS brain perceives & G unconscious controls Ls of body Organization of the nervous system T ↓ retina SNS ANS ↳ 3 iscussed nconsciousT · conscious · voluntary "rest & controls muscles "fight or flight" digest" controls organs t glands  sensory Overview of nervous system function neuron: takes into CNS + detects Stim Forms a coordination and communication network between all. parts of an animal’s body to produce behaviour (PNS) 1. Sensory Input: conduction of signals from sensory receptors to the CNS cell bodies in PNS ; axons in CNS 2. Integration: analysis and interpretation of the sensory ↳Interneurons signals and formulation of responses * w/in CNS 3. Motor Output: send command to effector cells to carry out response  sensory capabilities incoming , The brain’s past experience T primary function is to CPNS) produce behaviour (movement) -I outgoing CNS - effector cell Campbell Biology: Concepts and Connections First Canadian Edition Reece et al.  Directional flow of neural information Afferent = incoming information 07 ↓ a ton terminal cellbody Efferent = outgoing information afferent efferent X a > - - - - - v synapse  The human nervous system is composed of cells afferent dendrites Neurons: specialized nerve cells engaged in information processing carry signals from one location in the body/brain to another ↓ aton Human brain contains ~86 billion cell Isoma ↑ neurons! body > aron terminal - Campbell Biology: Concepts and Connections First Canadian Edition Reece et al. efferent Glial cells (glia): non-neuronal cells that support the function of neurons -microglia Nutritional support, immune function, regulators of neuronal signalling astrocytes ↳ ~85 billion! https://commons.wikimedia.org/wiki/File:Glia.png author: BruceBlaus  Neurons Most behaviors are produced by groups of hundreds or thousands of neurons circuit for Functional groups of neurons, or neural networks, connect wide areas of the brain and spinal cord Vary greatly in size and shape  Diversity in neuron morphology typically sensory internerrous newy fun bipolar unipolar Joaevites Purkinje > - only found in cerebellum Pyramid Neurons are information processing units dendrite Underlie plasticity Dendrites produced and retracted ↑ increased SA X from dendrites Dendritic spines may be added or pruned Neurons have up to 20 dendrites, each with many branches and up to 30 000 spines! Axon hillock: junction of soma and axon signal integration centre ↳ part of the cell ↳ axon body Axon collateral: Branch of an axon initial segment Telodendria (terminal branches): End branches of an axon Terminal button (end foot): knob at the tip Laxon of an axon that convey information to other neurons terminal / presynaptic terminal Synapse: special junction between one si AIS : 1st neuron and another; forms the information Og6 transfer site between neurons  Synapses form the basis of neuronal communication Presynaptic membrane: Output side of a synapse (usually an axon terminal/end foot membrane) Postsynaptic membrane: Input side of a synapses (usually a dendritic spine) Wa synapse lefferent can a happen anywhe &dendrit ent  Leterrier C. (2016). The Axon Initial Segment, 50Years Later: A Nexus for Neuronal Organization and Function. Current topics in membranes, 77, 185–233. https://doi.org/10.1016/bs.ctm.2015.10.005 -1st action potential u myelin sheath Axon initial segment: signal integration centre By Curtis Neveu - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=118090532  Anatomy basics – Navigating brain nomenclature Lack of coherence Multiple names; various languages, numbers, and letters Early investigators – named structures after objects, mythology, flora, fauna etc. E.g., pulvinar (Latin, “pillow”) E.g., hippocampus (Greek, “seahorse”) Contemporary – numbers and letters Many brain structures are named to reflect anatomical location  Frame of reference: human face Location is relative to point of reference Ex) anterodorsal nucleus of the thalamus A card E B rustral C Frame of reference: other body parts and body orientation superior I - - Chuman gradriped labels are different. interior  anterior = motor posterior= sensory -posterior Idorsal in 2 anterior quadriped eventral in guadriped 0 anterior posterior ↓ anterior root Curr root / afferent) dorsal (moterlefferent) https://www.gettyimages.fr/photos/spinal-cord-cross-section ganglion Anatomical orientation: frame dorsal of reference is direction of ⑪ cut/section through the human anterior posterior ⑪ ① brain from viewer’s perspective ⑪ -opposite most structures Xanterior/posterior contralateral to G represented bilaterally I < ventral to B ipsilateral same side ↓ > represented bilaterally * all the others are unilateral ① ⑫ O A C X dorsal/ventual B ⑪ O DD ① ① ④ & hemisphere X medial/lateral  The cerebral > - neocortex tes g-prim·oarsumry > the 4 lobes y a a - cortex ↓ allocortex (HPC & amygdala Cortex, Latin for “bark” movement Outermost layer of the cerebrum (aka forebrain) ·executive functions min > - planning, decision-making , personality Heavily folded (gyri learning& · and sulci), layered matter on memory A grey audition · structure outside; while matter · facial on inside recognition  M1 : precentral gyrus postcentral ras imm - = fissure: really biysucus sunt B ↓ motor coordination , ↳ categorized based on balance , motor learning developmental origins Schwann cells : PNS oligodendrocytes : CN (inside (outside) while matter tract that connects hemispheres (produce Istore CS F =) lons , broyancy · C choroid plexusdependymal cells cell bodies , dendrites , ↑ capillaries - axons Gray matter, white Schwanst wrapsround matter, reticular matter = ↳ mixture of Campbell Biology: Concepts and Connections First Canadian Edition Latin= net matter gray & white Reece et al.  cell body stain violet/ myelin stain > - cresyl Nissl body stain * nuclei & endoplasmic G reticulum Nuclei (sing. nucleus): a group of similar neurons ↳ forming a cluster (CNS) nuclei wl similar functions In the PNS – referred to as ganglia (sing. ganglion) -heceblage,  fasiculus: connects areas win the same hemisphere (intrahemispheric connection j Neurons are connected to one another by axons missures: connects homotopic areas in diff. hemispheres Tracts – large collection of I the CNS ↳ corpus :. e. Cinternemispheric axons coursing together INconnection)& a&llosum very large > - equivalent connects areas Nerves – OUTSIDE the CNS (i.e. PNS) Functional organization of the CNS Spinal cord executes most body movements Can act independently of the brain ↓ Spinal reflexes Automatic (unconscious) movements Hard to prevent (brain cannot inhibit) Example: knee-jerk reflex (patellar tendon)  in CNS; Istretch > - processes patellar receptor cell bodyinin tendon afferent I (posterior/dorsal root ganglich ! contracts inhibitory L CNS cell bodies in ; processes in PNS chamstring Campbell Biology: Concepts and Connections First Canadian Edition Reece et al. Spinal cord and nerves * know the order of groupings & mul Spinal cord lies within bony spinal column, made up small bones called vertebrae (sing. vertebra) (brainstem Find bran ↓ Each spinal nerve is associated with a spinal segment – grouped anal cord ↓ into 5 anatomical regions Runnerve *contralateral Each spinal segment corresponds in brain; ipsilateral to a region of body surface in nerve (dermatome), identified by the same number  Cross-section of the human spinal cord posterior-sensory up to brain- & motor processed in anterior = the opposite hemisphere Back afferent Left R nerve. efferent Front - The Law of Bell and Magendie No need to memorize  Cranial Nerves IEr important ANS & Functions laid out in Table 3.2, p. 63  Brainstem Ty forebrain ↑ sensory · > - brainstem info ↓ spinal cord Begins where spinal cord integrative. (sensorimotor ( enters skull sensory Receives afferent signals ↓ from body’s senses, sends motor part of the efferent signals out to spinal hindbrain cord to control most of body’s movements Responsible for most life- sustaining behaviour  mixture of gray & Brainstem – Hindbrain Y white matter Reticular formation: netlike mixture of nuclei and fiber pathways Nuclei located in patches along its length  sleep-wake behaviour and arousal (alertness) Sudiencephalon * stimulates forebrain -bridge > intense - damage = come Pons: bridge between cerebellum and rest of brain  vital body movements > - breathing facial > - movements Medulla: vital functions like breathing and cardiovascular system  Brainstem – Hindbrain cerebellum Coordination of voluntary movements Motor learning Integrates motor functions with mental processes Balance and posture Size increases with physical speed and dexterity of a species Primates: ~80% of all the brain’s cells  Parkinson Brainstem – Midbrain sendit tectum (Latin, roof): posterior sensory structure ↳ sensory Superior and inferior colliculi - -- G Produces orienting visual movements (e.g., turning-auditory 1 head to see source of sound) & scratching itches in specific location tegmentum (Latin, floor) anterior motor structure Species-specific behaviors IPAGT L Perception of pain (PAG) motor pain inhibition coordination  centre Brainstem – Diencephalon relay - > - olfaction > learning memory, - , attention (LGN) > - Visual (MON ↓ > auditory - bilateral T Q Thalamus Asorts incoming signals &sends to appropriate region of cortex ② Pituitary gland* hormone release ③ Hypothalamus* regulates pituitary (homeostatic functions)  > - hindbrain !!! Ebelow Public Domain, https://commons.wikimedia.org/w/index.php?curid=1298385  Hypothalamus the dies in CN cell goal-motivated > - contains 22 nuclei associated with all aspects of motivated behaviour including temperature regulation, eating, drinking, and sexual behavior etc. doesn't sustain ( ↳ non-regulatory ( life Controls bodies production of hormones via the pituitary gland  Thalamus mi SI central ↑↑ sulcus - O- pulvinar M for music ILGNILGBI ↑ ImmNIMGB) 20 nuclei, each projecting to a specific - area of neocortex Cerebrum aka Forebrain aka Telencephalon Cerebral cortex - neocort Chipprampus & amygdala Limbic system Basal ganglia bulbs · olfactory  Cerebrum aka Forebrain aka Telencephalon advanced cognitive functions such as thinking and language Cerebral Cortex (often referred to as just Claudate cortex) Neocortex: perception, planning, emotions, nucea memory 16 layers Constructs our reality eutament Allocortex: role in emotional and motivational states, certain forms of learning and memory 13 layers cardatee tum > evolutionarily older - Basal ganglia: coordination of voluntary movements Invclei) Gregulating movement force a  Forebrain – Basal ganglia Collection of nuclei below the white matter of the cortex coronal section striatum (diencephalon) functionally similar Hegmentum)  Forebrain – Basal ganglia oute r RobinH at English Wikibooks. - Transferred from en.wikibooks to By File:BrainCaudatePutamen.svg: User:LeevanjacksonDerivative work: User:SUM1 - Derivative work based on Commons., CC BY-SA 3.0, File:BrainCaudatePutamen.svg, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=85845448 https://commons.wikimedia.org/w/index.php?curid=36970335  Forebrain – Basal ganglia 3 main functions: 1. Connects sensory cortical regions to motor cortical regions 2. Regulates force of movement and movement fluidity actions have 3. Role in associative learning > - > - basicstimulus-response association consequences largely unconscious  Forebrain – The limbic system * emotionA > - sexual I white matter behaviour tract & > - social interactions npc( > - executive functions decision-making - white matter tract thalamus ALSO : Fear · anxiety. > prefiontal cortex (PFC) - · episodic memory basal ganglia > - · spatial nav. hypothalamus  Forebrain – The neocortex Humans: up to 2500 cm2 in area, but only 1.5-3 mm thick  - * Da- intra- parietal sulcus * A A * A & - Gyri csTscontains Sulci multimodal (many senses it can respond + cortex A I * S A anterior * pust. fissure > contains - * ~ must of V (10 Visual cortex) Major gyri and sulci  Cortical organization (10) -> from thalamus 1- 20 -> 3 : (bottom-up) Projection map (top-down) 3 10 > : -2 - > - anterior cortex 12 % Sensory info received by (PMC) primary area  secondary ° L , o ↓ area  posterior tertiary areas (form complex 30 (PFC) i VI associations)  frontal tertiary areas (action plans) posterior 30 ideas/concepts/perceptions - (30)/ association areas anterior 30-plans/goals  Neocortical layers 6 layers of grey matter Different layers have different cell types largerino - Cell density varies layer to IIIIIIIIII layer IIIIIIIIII IIIII Functional differences IIIIII between layers  Brodmann’s map - 52 are as > cytoarchitectonic map - BA22 = - Wernicke's are a BA44845 = Broca's area Korbinian Brodmann, Public domain, via Wikimedia Commons ①long Cortical connections connections blu lobes of one hemisphere - tracts ③ connections between ② shorter , within a hemisphere Lone homotopic points · (commissures) Fi ↑ X connections intranemispheric * Iranemispheric connections · fasciculvs  What about myelin? Giant axon of the msquid North Atlantic squid: 1 mm diameter (25 m/s) like a big water pipe ; > - I cell projections more H20/second CNS Mammalian: X Largest axons ~30 µm diameter and 10 m/sec Up to 150 m/s in a myelinated axon ↳ PNS ↓ cell itself a ton  Multiple sclerosis (MS) Most common autoimmune disease, usually diagnosed between 15-40 1 in 500 – 1 in 1000; 2X more likely in women in the myelin CNS is lost Loss myelin formed by oligodendroglia Hard scar (plaque) forms at site of myelin loss, which can be visualized by MRI Disrupted ability of neurons to propagate action potentials efficiently Symptoms: Blurred or double vision Extreme fatigue women = I Loss of balance Prevelance of Muscle stiffness issues sensory Speech problems Bladder and bowel problems Short-term memory problems Loss of sensation and motor control, usually appearing first in hands or feet  Communication in the human nervous system 86 billion neurons and trillions of synapses F Each neuron receives info from hundreds of other neurons excitatory or > - inhibitory  thousands of synaptic terminals per neuron Axon initial segment = site of integration Campbell Biology: Concepts and Connections First Canadian Edition; Reece et al. (2015)  Two modes of synaptic communication vertebrae 3-5 ms > - primary synapse in > - delay = > - Chemical synapse: Junction at which messenger - molecules are released when stimulated by an action potential Neurotransmitter: Chemical with an excitatory or inhibitory effect when released by a neuron onto a target ↳ post-synaptic receptors' response determines effect - invertebraes of neurotransmitter Electrical synapse: Electrical synapses are specialized connections between neurons that facilitate direct ionic and small metabolite communication ~ no gap blu membranes ; no cell is really pre/post-synapse ↓ Gap junction: area of contact between adjacent cells formed by hemichannels composed of connexin proteins. response mirrored in adjacent cell  to axon transports Chemical synapses ↑ terminal vesicles , cast channels , e+ c Y. as - 'post-synapt A M part of tripartite = provide precursor Synapse molecules , neuro clean-up  Electrical synapses > activitycan be synced in cells - connected wl electrical synapse gapjunction - Anemichannel no cell - is really > - made of connexin proteins pre/post- Synapt M M M ↓ bidirectional information De Michele, Pasquale. (2015). Analysis, tuning and implementation of neuronal models simulating Hippocampus dynamics. 10.6092/UNINA/FEDOA/10322 - transfer ~ Chemical - Advantages Electrical – Advantages Flexibility Instantaneous signal transfer – allows for synchronization i.e. strengthening or weakening of between large population of a synapse based on changes to neurons pre- and postsynaptic terminals eta ~ ↳I. channels of receptors =synaptic plasticity – the capacity for change *Very important or learning and memory  Why are synapses so important? Sites of: Learning and memory Strengthening or weakening of synapses Drug action > of drugs wl affect on nervous system - Caffeine, nicotine, alcohol, antidepressants, illegal drugs, THC Neurological disorders (neurodevelopmental and neurodegenerative) Depression, schizophrenia, ADHD, autism, Alzheimer Disease etc. lies & the ↳ most dysfunction synapse Anterograde synaptic transmission S ↓ small molecule class forward synthesized e - in the moving direction synaptic terminal  Neurotransmitter release ↳ mediated Ca* & its channels by ion. Car + 2) V G. Channels activated bound to actin -cast cytoskeleton; ↓o association tregion rich in 1) action potential cast channels & arrives ↓ > - Nat influx neuropeptide dedVezIGle? treadily > not - docked , so not necessarily releasible reserves readily pool releasible & VG. Nat. activ channels filaments ‘Active Zones’ by Casey Henley is licensed under a Creative Commons Attribution Non-Commercial Share- Alike (CC-BY-NC-SA) 4.0 International License.  Neurotransmitter Classes 1. Small-molecule transmitters main focus 2. Peptide transmitters Of this course 3. Lipid transmitters 4. Gaseous transmitters NO CO , Has just know that , 5. Ion transmitters Znat these exist  TABLE 5-1 Best-Known and Well-Studied Small- 1. Small molecule Molecule Neurotransmitters neurotransmitters * Acetylcholine (ACh) Amines > characterized by a mire - Class of quick-acting * Dopamine (DA) C-NH) group ; made from neurotransmitters acid precursor * Norepinephrine (NE, or noradrenaline [NA]) a mino -> synthesized on demand I A Epinephrine (EP, or adrenaline) e terminal * Serotonin (5-HT) Synthesized from dietary Amino acids ↳ nutrients and packaged determines > - * Glutamate (Glu) identity ready for use in axon * Gamma-aminobutyric acid (GABA) terminals Glycine (Gly) double ring Histamine (H) ~ Purines Once released, are quickly Adenosine replaced at presynaptic Adenosine triphosphate (ATP) - membrane adenosine  The 4 major activating systems neural pathways that coordinate brain activity through a single NT role in synchronization of activity across widespread brain regions 1. Cholinergic system 2. Dopaminergic system 3. Noradrenergic system 4. Serotonergic system * all small molecule neurotransmitters > - primarily ACh heart , but also in brain - post-synaptic 1st NT discovered - - ↳ pre-synap t Works primarily at I nicotinic actylcholine receptor the neuromuscular nicotine > agonist - = junction (including heart) ↓ synapse blu motor neuron & muscle cell i.e., activates depolarization (4 + ++ + + ) skeletal muscles in the SNS this * process is responsible for voluntary movement  ACh Chemistry ACh = choline + acetate fatty ↓ foods acidic foods 3 key enzymes in synthesis/degradation: I Acetyl CoA acetyl coenzyme A > - ChAT choline acetyl transferase Esynthesis > - extracellular Suffix fluid AChE achetykholinesterase ~ -> denotes a protein ↑ degredation  ACh in the CNS (Cholinergic Activating System) -D waking behaviour * * learning & memory left compared 2 Nuclei ACh = slightly - to sources diagram projections to... > neocortex - > - HPL > - amydala  DA Like other amines, synthesized from amino acid precursors ↓ amine Tyrosine (hard cheeses and bananas are group good sources) Involved in coordinating movement, attention, learning, motivation, and reward processing etc. SN basal ganglia (striatum / Implicated in Parkinson Disease - tegmentum > Degeneration of the substantia nigra, a small midbrain nucleus Symptoms appear when DA levels have been reduced to less than 10% of normal levels in the basal ganglia tremors postural · · rigidity instability · slowness ·  Sequential synthesis of 3 amines tyrosine > - hydroxylase di Levodopa Rate-limiting factor: supply of tyrosine hydroxylase is limited · monoamines lamine neurotransmitters) > - caudate , putame a llidus ,  DA in the CNS SN- X striatum involuntary & erratic movements I withing- "reward Pathway" - IVTA) ↓ ↳ UTA- NA, HPC , too much da amygdala , PFC Schizophrenia ; too little- ADHD =  Parkinson Disease Shaking usually first symptom, typically beginning in a hand Propensity to lean forward/run forward to prevent falling As progresses – essential functions such as eating, swallowing impaired Cause: several genes have been implicated, environment may also play a role 5-HT Synthesized from the amino acid tryptophan (abundant in milk, pork, turkey, bananas etc.) Role in regulating waking activity, mood and aggression, appetite, sleep, memory, respiration, pain perception 5-HT in the CNS ↓ +/ > - ↑ ↓  NE in the CNS & emotional X learningt memory LC > allocortex - , neocortex , brainstem , cerebellum > in - reticular formation  GABA and Glutamate Amino acid subclass of small molecule class - used in many Workhorses of the brain synapses In forebrain and cerebellum - exception to rule of > receptor mediated Glutamate = main excitatory NT excitation/inhibition Key player in learning and memory, especially in hippocampus and cortex GABA = main inhibitory NT Learning and memory, brain development 2. Peptide transmitters Family Examples 50+ Opioids Met-enkephalin, dynorphin, beta-endorphin Short amino acid Neurohypophyseals Vasopressin, oxytocin chains (fewer than 100) Secretins Secretin, motilin, glucagon, growth hormone-releasing factor Translated from Insulins Insulin, insulin growth mRNA factors not synthesized Most are ↑& terminal Gastrins Gastrin, cholecystokinin Somatostatins Somatostatin assembled by Tachykinins Neurokinin A, neurokinin B, ribosomes located substance P in cell body 2. Peptide transmitters hormone = released into blood local effect & has distant Stress hormones (e.g., cortisol) target Bonding hormones (e.g., oxytocin) Regulate eating/drinking (e.g., orexin) Modulate pleasure/pain (e.g., endogenous opioids such as endorphins, enkephalins, dynorphins) May contribute to L&M Etc. 3. Lipid transmitters Endocannabinoids Synthesized at postsynaptic membrane to act on receptors at presynaptic membrane A retrograde synaptic transmission Anandamide (AEA) and 2-AG (2-arachidonoylglycerol) derived from unsaturated fatty acids (poultry and eggs) Sanksrit ananda, “joy” or “bliss” & AEA action mimicked by THC (tetrahydrocannabinol) 3. Lipid transmitters - endocannabinoids Appetite, pain, sleep, mood, memory, anxiety, stress Hydrophobic, thus not stored in vesicles > - synthesized on demand ; cannot be stored in vesicle retrograde NTs, reduce amount of small-molecule NT released C CB1 receptors; found at glutamatergic and GABAergic synapses - can modulate excitatory /inhibitory synapse  Two classes of neurotransmitter receptors (ligand-gated ion ( channels 1. Ionotropic receptor: embedded membrane protein that acts as both a binding site for NT and a pore that regulates ion flow ↳ neurotransmitter ligand = a (4-protein coupl 2. Metabotropic receptor: embedded membrane protein with a binding site for a NT Linked to a G protein > - Guangl nucleotide-binding protein Ionotropic receptor Cl hyper = Nat/k de =. Isynaptic cleft) post-synaptic membrane  Metabotropic receptor G proteins can: Trigger opening/closing of ion channels Initiate intracellular signaling cascades, resulting in the insertion of additional NTRs don't have ; * a pove activate other channels NT Ionotropic Receptors Metabotropic Receptors ACh acetylcholine Nicotinic - Muscarinic (5) DA dopamine - Dopamine (5) GABA GABAA GABAB Glu glutamale - NMDA, AMPA, kainate mGluRs (7), NMDA Gly glycine - Glycine, NMDA -histamine H * lots of responses a single NT Histamine (3) NE can mediate a NE alpha (8), NE norepinephrine - beta (3) 5-HT serotonin - 5-HT3 5-HT (12) 10 Principles of Nervous System Function O 1 Neuronal circuits are the functional units of the nervous system > - functional unit 2 Sensory and motor divisions pervade the nervous system 3 The CNS functions on multiple levels and is organized hierarchically and in parallel exceptions - O hemisphererespondstubudySNIENS connections & 4 Many brain circuits are crossed - 5 Brain functions are localized and distributed 6 The brain is symmetrical and asymmetrical 7 G The nervous system works by juxtaposing excitation and inhibition 8 The brain divides sensory input for object recognition and movement O 9 The nervous system produces movement in a perceptual world the brain constructs > responds to stimuli (vibrations = sound) - C 10 Neuroplasticity is the hallmark of nervous system functioning 2. Sensory and motor divisions pervade the nervous system. Ex) Law of Bell and Magendie (SNS – spinal nerves): anterior/ventral root = efferent, posterior/dorsal root = afferent This organization extends into the CNS as well Hindbrain and midbrain  posterior is sensory, anterior is motor Cortex  separate regions process sensory vs. fine motor outputs Q Layer IV receives sensory inputs; layers V and VI send motor outputs 3. The CNS functions on multiple levels… ↳ simple animals- simple nervous systems Simple animals, such as worms, have a spinal cord. More complex animals, such as fish, have a brainstem as well, and yet more complex animals have evolved a forebrain. o previous levels not lost => evolution is additive Each new addition to the CNS has added a new level of behavioral complexity without discarding previous levels of control.  a...and brain systems are spinal organized hierarchically and in brainstem ↓ parallel. cortex double-headed arrow = Multiple hierarchically organized circuits reciprocal ↑ stimulus: movie relationship acting in parallel enable the performance of complex and/or simultaneous behaviours brainstem Ex) watching a movie and eating popcorn Sub- cortical lots of things going on at once · -many levels wind blu hierarchies nescortex these perception Al mu VI SI dresimultaneous  The “binding problem” How does the brain bind features together of a single object? - smell sound story etc., , , has diff sensory processes in one ↳ memory many. How does the brain put all the separate objects together into one coherent scene/unified consciousness? 5 and 6. Localization and lateralization of function Some functions/behaviours are controlled by one specific region => localized Other functions are parsed apart, and processed (in parallel) in completely separate regions dist but => distributed-memory are localized. aspects mem HPC) (episodic = Some functions are represented bilaterally, others are localized on one side of the brain => lateralized Lateralization of speech and patient “Tan” -history of epilepsy 1861, Monsieur Leborgne, had lost his speech and was transferred to Broca’s care most func. distributed specific brain - leading belief ↑ regions Pivotal case in the “holism” vs. “localization” debate, and the discovery of language lateralization Paul Broca · left frontal lobe & speech production 1824 - 1880 CT scan of a subject with Broca’s Aphasia in ability ↳ to produce Broca's lateralized area - speech ↑ to left hemisphere O * comprehension not affected A Wernicke aphasia : lack of speech Wernicke-Geschwind Model- language - is comp. a localized (1) comprehension ↳ in temporal lone (bilateral function => not aware of could 11. don't know somethings wrong Classical anterior and intra hemispheric posterior speech connection zones are connected um by the arcuate in premotor Cortex Al fasciculus insuperior temporalus 8. The brain divides sensory input for object recognition and motor control Ex) dorsal and ventral visual processing streams colour , lines , Ventral: vision for movement selem). but identification/recognition (“what” stream) concept => occipital temporal to Conscious * * facial gone = > recognition Dorsal: vision for action (“how” stream) => occipital to dorsal↳ grasping * unconscious A gone This is also an example of parallel retina > thalamus -occipital lobe - info processing! (principle 3) ↳ dorsal stream ventral stream Top Hat