2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 1 Development of Complex Curricula for Molecular Bionics and Infobionics Programs within a consortial* framework** Consortium leader PETER PAZMANY CATHOLIC UNIVERSITY Consortium members SEMMELWEIS UNIVERSITY, DIALOG CAMPUS PUBLISHER The Project has been realised with the support of the European Union and has been co-financed by the European Social Fund *** **Molekuláris bionika és Infobionika Szakok tananyagának komplex fejlesztése konzorciumi keretben ***A projekt az Európai Unió támogatásával, az Európai Szociális Alap társfinanszírozásával valósul meg. PETER PAZMANY CATHOLIC UNIVERSITY SEMMELWEIS UNIVERSITY sote_logo.jpg dk_fejlec.gif INFOBLOKK 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 2 Peter Pazmany Catholic University Faculty of Information Technology BEVEZETÉS A FUNKCIONÁLIS NEUROBIOLÓGIÁBA INTRODUCTION TO FUNCTIONAL NEUROBIOLOGY www.itk.ppke.hu By Imre Kalló Contributed by: Tamás Freund, Zsolt Liposits, Zoltán Nusser, László Acsády, Szabolcs Káli, József Haller, Zsófia Maglóczky, Nórbert Hájos, Emilia Madarász, György Karmos, Miklós Palkovits, Anita Kamondi, Lóránd Erőss, Róbert Gábriel, Kisvárdai Zoltán Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 3 www.itk.ppke.hu Control of movement Imre Kalló Pázmány Péter Catholic University, Faculty of Information Technology I. Neuromuscular system. Regulation of locomotion at the level of the spinal cord. II. Regulation of posture and balance. The medial postural system. III. Regulation of fine movements. The lateral voluntary system. Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 4 Movement serves survival by enabling Self-propagation -feeding Self-protection (”flight or fight”) Species-propagation –reproduction Species-protection (communities, societies) Biodiversity-propagation Biodiversity-protection Someofthemovementsareinvoluntary(reflexes,fixedactionpatterns),somerhythmicmovementsareautomaticallycarriedoutundercontinuousvoluntarycontrol(rhythmicmotorpatterns-locomotion)andsomemovementsarevoluntary(directedmovements). www.itk.ppke.hu Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 5 Locomotion–for many species the capability to change location means survival (finding new food resources, protective environment, a mate etc.) Based on the observations on the life cycle of "sea squirt", Rodolfo R. Llinas suggested that the nervous system evolved to allow active movement of theanimals. Bluebell_tunicates_Nick_Hobgood sea_squirt Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 6 Speed, force, dimension and complexity of movement are determined by 1. Biomechanical properties of the skeleto-muscular system 2. State of thedevelopment of nervous system phylogenetically ontogenetically cheetah-running-small-13.jpg 4246008350_8d239c57e3_z.jpg marathoner_sprinter21 copy.jpg Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 7 1. Biomechanical properties –structure and function of skeletal muscles www.itk.ppke.hu muscle_structure_full_size_landscape Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 8 www.itk.ppke.hu d1 MotorUnits Muscle fibers contract in response to excitation. Fibers belonging to different motor units are intermingled. Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 9 www.itk.ppke.hu Speed and force of contraction depend on the muscle fibers involved. f1 copy Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 10 Muscle tension is regulated by motor neuron firing rate .Hierarchicaland asyncronousactivation of motor units! www.itk.ppke.hu e1 copy2 e1 copy Single MUs -Twitch Contractile force is maintained by Summation Incomplete tetanus Tetanus Effect of extra and missing impulses Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 11 Muscle tension is modulated by receptors sensing active and passive tension, as well as static and dynamic changes during muscle contraction. Gain adjustment is possible in the muscle spindle. www.itk.ppke.hu h1 copy i1 copy j1 copy Golgi tendon organ Muscle spindle - nuclear bag (static and dynamic) -nuclear chain Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 12 2. State of the development of nervous system More advanced nervous system means higher complexity of movements.Maturation of the CNS shows species variations. www.itk.ppke.hu for pres_cliona_limacina_a_full.jpg forPres_td-learning-to-walk.jpg forPres_step-reflex.jpg images.jpg Human development.jpg 20-40. weeks 2 months 10 months 12 months 14 months Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 13 Human gait is composed of phasic and tonic components -the phasic component means the rhythmic alternating contractions of limb and trunk muscles, produced mainly by central pattern generators –CPGs are functional at birth -the tonic component is associated with postural muscles and quite immature at birth –it becomes functionalby the maturation of -the musculoskeletal system -the sensorimotor networks -higher brain centers -descending motor pathways -ascending sensory pathways Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 14 CPG for gait control is located in the spinal cord. Cats with total spinal cord lesion can walk on a moving platform (with supported body) after recovery from the traumatic shock. Spinal cord: protective reflexes walking Brainstem: chewing, swallowing, breath taking , walking eye movements Cerebral cortex: speech, hand-finger movements Basal ganglia: initiation of movement behavior Diencephalon: eating, drinking Cerebellum: co-ordination of movements association of stimuli 2 3 CNS lesions resulting in impairment of movements 1. Spinal cord injury 2.Decerebration 3.Decortication 1 Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 15 Thenetworkresponsibleforcontrollingwalkingdevelopsduringtheembryoniclife.Adorsoventralgradientofbrainmorphogenstriggertheexpressionoftranscriptionfactors,whichinturndeterminedifferentiationofneuralstemcellstointerneurons(V0-V3)andmotoneurons(MN). www.itk.ppke.hu Interneurons V0 -coordination of left-right alternation (contralateral) V1 -speed of MNs output (ipsilateral inhibition) V2 -burst robustness left-right alternation V3 -burst robustness Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 16 Anetworkofspinalneurons(composedofinterneuronsandmotoneurons)generatesarhythmicmotorpattern.Duetoitscomplexityinvertebrates,itisdifficulttoinvestigatetheregulatingneuronalnetwork,whichisthereforelargelyunknown. www.itk.ppke.hu Themajorobservationsaboutthefunctionofcellularcomponentsandtheoperationalrulesoftheneuronalnetworkgeneratingtherhythmicmotorpatternderivefromstudiesonorganismswithrelativelysimpleneuronalsystemsi.e. clione lobster leech lamprey Introduction to functional neurobiology: Control of movement 17 Network (model) response Cellular (neurons) response ModelNeuronalNetworks_b.jpg ModelNeuronalNetworks_a.jpg Central (motor) pattern generator(CPG, MPG):Neuronal network, which iscapable to maintain arhythmic output without rhythmic sensory or central input Rhythmsare either generated: -by endogenously oscillating neurons (currents)or -by network activity of non-oscillating neurons 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 18 Reciprocal Inhibition_a&b Reciprocal Inhibition_c Postinhibitoryreboundleadtogenerationofactionpotentials!„anodebreakspike” Commonphenomenon:voltage-dependentNachannelsorT-typecalciumchannelsarepartiallyinactivatedattherestingpotential.Transienthyperpolarizationreleasethechannelsfromtheinactivatedstate.Thresholdoftheactionpotentialwillbelower. Electrical properties of the participating neurons determine -oscillation in network output -activity of neurons -period of rhythms Half-centeroscillator:Twoneuronsconnectedinreciprocalmannergeneraterhythms–alternatingmuscularcontractionandrelaxation Clione–two-neuron system Introduction to functional neurobiology: Control of movement a.jpg a.jpg b.jpg c.jpg 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 19 LobsterStomach PyloricRhythm Lobster –multi-neuron system Rhythmgenerationisdependentontheactivityofothercells–networkinputisessential!Thereleasedneurotransmitteraltersthemembranecharacteristicsoftheneuronswithinthenetwork! ABcellshowsconditionalburstactivity!Whenitisactive,ashortdepolarizationinducesadriver(plateau)potentialinLPneuron! Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 20 Lobster -neuromodulators alter network activity and output. Rewiring_PyloricNetwork_a Rewiring_PyloricNetwork_b1 Rewiring_PyloricNetwork_b2 Experiment:Removing neuronal input (GABA, serotonin, dopamine, FMRFamide-like peptide etc.), adding neuromodulators Alteration of excitability of neurons and synaptic strength within the network results in different outputs! Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 21 Leech_a Leech_b Leech-command neurons in the network activity Trigger neurons receive input from sensory neurons and initiate rhythmic activity of MPGs Gaiting neurons determine the duration of the MPGs activity –the duration of the swim Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 22 Leech-command neurons in the network activity TriggerNeurons Shortactivationofthe„trigger”neuroninducesalong-lastingactivationofthe„gating”neuron,whichinturnleadstoalong-lastingburstactivationofCPGsandthemotoneurons. Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 23 ForPres_19-9.jpg Lamprey-command systemof vertebrates CPGsarecomposedofexcitatory(E)andinhibitoryinterneurons(L&C).“C”interneuronsareinreciprocalinhibitionwithitspairintheotherhalf-center.Stretchreceptors(SR)sendexcitatoryandinhibitoryfeed-backtoCPGs.Excitatoryreticulospinalneurons(R)induceplateaupotentialsinthepattern-generatingneurons.RoleofNMDAreceptorsistoincreasecalciumlevels,whichinturnactivatecalcium-dependentpotassiumchannels. Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 24 Summary –what can be predicted for the operation of MPGs in mammals (humans): • similar membrane events (postinhibitory rebound, driver potential etc) • similar reciprocal connection of half-centers • neuromodulators influencing electrical properties of network elements • cellular components brought in action determine the output signal of the network • the existence of higher command system • peripheral signals exert also strong influence on the MPGs Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 25 DorsalRootStimulation Mouse–Rhythmic burst activity of CPGs and motoneurons can be induced by stimulating dorsal roots for a longer period Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 26 HB9expressingspinalmotoneuronsandinterneuronsintheneonatalmousespinalcordshowningreenbythereporterfluoresceinprotein. Anexcitatoryinterneuronisrecordedandfilledwithbiocytin. www.itk.ppke.hu cover-horiz-sb TheHb9interneuronactivityischaracterizedbyrhythmicmembranedepolarizationunderlyingactionpotentials.Theactivityisinphasewiththeactivityrecordedfrommotor neurons(ventralrootrecording). Hinckley et al, JNeurophysiol, 2005 Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 27 www.itk.ppke.hu Motoneurons Muscles Renshaw cell Ia Inhibitory IN Hb9 Excitatory IN CIN -Excitatory CIN -Excitatory CIN -Inhibitory The mammalian CPGs are modulated via interneurons Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 28 Descending pathways.jpg Comissural interneurons (CINs) receive information from descending motor pathways Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 29 Interneurons on the ipsilateral side transfer stimulus from the skin, which modify the motor program and consequently the firing activity of motoneurons r1 copy Region-specific Modality of the stimulus determines the response Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 30 Postureandbalanceismaintainedbycontinuousprocessingofsensory,vestibularandvisualinputsandgenerationofcompensatorymuscularcontraction. 1. Sensory -proprioceptiveinputs 2. Vestibular input 3. Visual input Proprioceptionmeans the unconscious sense of self position and movement. Regulation of posture and balance Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 31 Changes in the physical contactof the body with the support surfacetrigger compensatory actions through stretch reflexes l1 copy This reflex -has phasic and tonic components -involves reciprocal innervation of the antagonistic muscles -is characterised by motor output to all homonym and ~ 60% of synergistic muscles -is characterised by adjustable sensitivity through setting fuzimotor fiber activity -can be modified by presynaptic inhibition of the afferent fibers -Is characterised by direct synaptic input to MNs; the delay is 0.5-0.9 ms Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 32 Posture is maintained even, if rapid changes occur in the body support –a „built in” mechanism of the nociceptive reflex s1 copy Multisensory convergence – Loss of specificity of sensory processing Contralateral inhibition offlexorMNs Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 33 Different mechanisms are adapted to the various positional changes of the support surface Exp:_ Moving platform triggers the ankle strategy -feed-back mechanism Activation of the muscles distal to proximal direction e.g.: forward movement of platform –backward sway: activation of TA-quadriceps muscles-abdominal muscles Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 34 Different mechanisms are adapted to the various positional changes of the support surface Exp:_ Tilting platform triggers the hip strategy -feed-back mechanism Activation of the muscles proximalto distaldirection e.g.: forward tilting –forward sway: activation of paraspinalis (erector spinae) –ham string muscles –triceps surae muscle Similar action, when the movement of the platform isLARGERand FASTERorwhen the surface is COMPLIANT (soft) or NARROW Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 35 Feed-back corrections, when the postural disturbance is unexpected Feed-forward corrections, when the postural disturbance is expected x1 copy Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 36 The extent of muscle contraction depends on previous experience and expectationsFeedforward or preventing mechanisms are triggered Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 37 Cortical neurons respond to small disturbances i2 copy2 j2 copy Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 38 Thevestibularnucleiareinconnectionwiththecerebellum,whichreceivesensoryinformationfromthebody.Themediallongitudinalfasciclecontainsfibersofsuperiorvestibularnucleusprojectingtothemotornucleioftheeye.Thelateralvestibularnucleusprojecttothespinalcordtoactivatetheextensormusclesoftheipsilaterallimbs. Themedialposturalsystemprocessesproprioceptive,vestibularandvisualinformationsandconveysmotorresponsestothespinalcord.Itinnervatestheaxialmusculatureandtheproximalpartsofthelimbs. Vestibular regulation.jpg Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 39 Exp:Vestibulocervical and vestibulospinal reflexes stabilize head and body posture Stretchintheneckmusclesandstimuliofthevestibularorganexcitepathwaysthatcontractneckandlimbmusclestoopposeanundiseredmovementofthebody. Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 40 Removal of the visual input –only the proprioceptive and vestibular sensors are in action -Romberg test It is positive in the case of cerebellar, proprioceptive and vestibular damage. Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 41 Summary • Stabilityofthebodyisprovidedbyfeed-forwardcontrolandrapidfeedbackcompensatorycorrections • Vestibularandneckreflexesstabilizetheheadandsight • Brainstemandspinalcordmechanismsparticipatealsointheposturalcontrol Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 42 Voluntary movement Locomotion can be initiated by the activation of many neurons distributed in several discrete regions of the brain. Spinal cord: protective reflexes walking Brainstem: chewing, swallowing, breath taking , walking eye movements Diencephalon: eating, drinking Cerebellum: co-ordination of movements association of stimuli 2 3 1 Cerebral cortex: speech, hand-finger movements One of the principal site is in the brain stem, but tonic inhibition of this site from the basal ganglia normally prevents locomotion. Basal ganglia: initiation of movement behavior Introduction to functional neurobiology: Control of movement 2011.10.12.. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 43 Initiation of movement from the basal ganglia. Role of disinhibition. Output through the pallidum Input from the striatum Output Cerebral cortex Thalamus Brain stem Cerebral cortex Thalamus Diencephalon Mesencephalon Substantia Nigra Dopamine Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 44 The lateralvoluntarysystem Lateral&medial rendszer The corticospinal pathway The (cortico-) rubrospinal pathway Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 45 Cortical areas involved in motor control Their ablation results in deficits in movements, their stimulation induces or alters movements Cytoarchitectonic areas 4 and 6 Brodman (and areas 1, 2, 3, 5, 7 and 24) They communicate with other motor structuresand receive area-specific subcortical (thalamic and basal ganglia) and cortical afferents. Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 46 Motor cortical areas receive input from other cortical areas, as well as subcortical areas e2 copy Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 47 Somatotopic representation in monkeys and humans A large overlap in the representation fieldsof body parts, muscles or movements! ”New ”M1 bypasses spinal cord mechanisms and enables novel patterns of motor output Rathelot, PNAS, 2009 Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 48 The primary motor cortex is agranular –predominantly there are pyramidal cellsat this site d2 copy Layer 4 is reduced or absent, no internal granular layer! Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 49 Convergence and divergence characterize the M1 neurons f2 copy Convergence–they are distributed in complex mozaik arrangement Divergence–they ramify in multiple spinal segments Dancause N et al. Cereb. Cortex 2006;16:1057-1068 Published by Oxford University Press Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 50 Plasticity ofthe motor cortex It occurs: -afterdenervation of one part of the body -when amuscle is stretched passively –rehabilitation after stroke -when muscles are used intensively for prolonged period Paired associative stimulus (electric stimuli of Median Nerve followed by TMS) Motor-evoked potential (MEP) amplitudes are substantially larger in active subjects! Cirillo J, J.Physiol., 2009 Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 51 Several cortical areas are activated during planning and execution of voluntary movements. Khushu, J.Biosci, 2001 By complex hand movements bilateral activation of the: Sensorimotor areas Supplementar motor area Ventrolateral premotor area contralateralactivation of the: Dorsolateral premotor area Medial cortical areas rostral to the SMA Cortical electrical potentials 1s prior to movement! Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 52 M1 neurons regulate kinematics and dynamics of movement Discharge of neurons is correlated with force, directionof the movement, position of the joints and velocity. Single cell recording. g2 copy Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 53 Ensemble activity of a large population of cortical neurons is tuned for a particular direction of movement h2 copy i2 copy Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 54 Cells in the premotor area encode the direction of the planned movement Wise and Strick, 1996 PMA_delayed activation_2.jpg majom kísérlet.jpg Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 55 majom kísérlet.jpg Visual-Internal cues.jpg 1. 2. 3. 4. 5. 1. 2. 3. 1. 2. 1. 2. 3. 3. Internal cues 1-3 External cues 4-5 1. 1. 2. 2. 3. 3. Internal cues activate cells in the SMA, whereas cells in the premotor area are active in response to visual cues Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 56 Local increase in blood flow shows also the role played by the supplementer motor area during mental rehearsal of motor tasks nrn2805-f1 Parieto-frontal mirror neuronal circuit Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 Nature Reviews Neuroscience 11, 264-274 (April 2010) nrn2805-f2 Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 Nature Reviews Neuroscience 11, 264-274 (April 2010) The premotor neurons encode the goal of the movement nrn2805-f3 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 Nature Reviews Neuroscience 11, 264-274 (April 2010) Introduction to functional neurobiology: Control of movement Mirrorneurons may encode the goal of the motor acts of another individual in an observer-centredspatial framework. Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 60 Functions of the premotor cortex -Summary 1. Orchestration of proximal muscles during limb movements. 2. Control of visual and acoustic stimuli induced voluntary movements. 3. Preparation of movements and setting the postural positions to carry out movements. 4. Activation of premotor area to enhance the subsequent motor response. Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 61 Functional disturbance of M1 and the premotor area l2 copy Apraxia: Damage of left parietal lobe, PMA and SMA Movements of the apraxic patients are tentative and irregular. Lesions in the primary motor cortex result in weakness in the contralateral side of the limbs. In contrast, lesions in the premotor areas cause impairment of strategic plans to carry out the movements. Akinetic mutism: Serious damage leads to akinetic mutizm. Patient do not move and do not speak. Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 62 Lesion of the supplementer motor area results in a deficit in the bimanual coordination. m2 copy Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 63 1. Planning of movements –control of planned movements 2. Initiation of speech by activating the motor speech areas 3. Orchestrating center of cortico-subcortico systems of movement initiation 4. It organizesthe orientation of attention to stimuli. 5. It influences the brainstem and spinal cord motoneurons via neuronal connections 6. It plays important role in coordinating posture and voluntary movements. Functions of the supplementer motor area-Summary Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 64 Functional disturbance of the posterior parietal cortex 1. Severe attentional disturbances. 2. Mistakes, when locating objects in space. 3. Inability to recognise complex objects or to draw in 3D. 4. Patients can not perform complex gestures. 5. Neglect of tactile or visual stimuli on the contralateral side of the body. Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 65 Processing of visual information –external cues -PM Simple reaction time ~160 ms Choice reaction time is increasing with the number of alternative responses and with age! ChoiceReactionTime.jpg Introduction to functional neurobiology: Control of movement 10/12/2011. TÁMOP –4.1.2-08/2/A/KMR-2009-0006 66 Summary: voluntary movement Motor areas are characterized by somatotopic organization Neurons in the primary motor cortex encode the direction of the force during movement The premotor and supplementer cortical areas prepare the motor system for the movement The posterior parietal lobe provides the visual information for the targeted movements