* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download BN16 Neural plasticity
Central pattern generator wikipedia , lookup
Subventricular zone wikipedia , lookup
Neuroanatomy wikipedia , lookup
Types of artificial neural networks wikipedia , lookup
Human brain wikipedia , lookup
Neuroeconomics wikipedia , lookup
Aging brain wikipedia , lookup
Biology of depression wikipedia , lookup
Clinical neurochemistry wikipedia , lookup
Apical dendrite wikipedia , lookup
Optogenetics wikipedia , lookup
Embodied language processing wikipedia , lookup
Synaptic gating wikipedia , lookup
Neural correlates of consciousness wikipedia , lookup
Molecular neuroscience wikipedia , lookup
Chemical synapse wikipedia , lookup
Muscle memory wikipedia , lookup
Activity-dependent plasticity wikipedia , lookup
Neuropsychopharmacology wikipedia , lookup
Neuroanatomy of memory wikipedia , lookup
Environmental enrichment wikipedia , lookup
Feature detection (nervous system) wikipedia , lookup
Perception of infrasound wikipedia , lookup
Development of the nervous system wikipedia , lookup
Premovement neuronal activity wikipedia , lookup
Cognitive neuroscience of music wikipedia , lookup
Circumventricular organs wikipedia , lookup
Synaptogenesis wikipedia , lookup
Motor cortex wikipedia , lookup
Cerebral cortex wikipedia , lookup
Microneurography wikipedia , lookup
Long-term depression wikipedia , lookup
Neural Plasticity: Long-term Depression Lesson 16 Long-term Depression Hippocampus Low frequency stimulation 1 Hz over 10-15 min 2+ -dependent NMDA & Ca 2+ phosphatase activity Low Ca Cerebellum mGlu1-R Different mechanism ~ Cerebellum Motor functions Coordination of movements Regulation of posture Indirect control Adjust outputs of descending tracts Also nonmotor functions memory/language ~ Cerebellum: Anatomy Folia & lobules analogous gyri & lobes Vermis - along midline output ventromedial pathway Hemispheres output lateral pathway Deep cerebellar nuclei fastigial, interposed, & dentate Major output structures ~ Spinocerebellum Cerebrocerebellum F a s t i g i a l Vestibulocerebellum I n t e r p o s e d Dentate Cerebellum Programs ballistic movements feed-forward control no feedback during execution direction, force, & timing long term modification of circuits Motor learning shift from conscious unconscious ~ Cerebellum Acts as comparator for movements compares intended to actual performance Correction of ongoing movements internal & external feedback deviations from intended movement ~ Cerebellum: 3 layered cortex 1. Molecular layer parallel fibers axons of granule cells runs parallel to long axis of folium ~ Cerebellum: 3 layered cortex 2. Purkinge cell layer large somas axons to underlying white matter perpendicular to main axis of folium ~ Cerebellum: 3 layered cortex 3. Granular layer • innermost layer small, densely packed granule cells > # neurons in cerebral cortex ~ Cerebellum: 3 layered cortex Molecular Purkinje Granule Cerebellum: & Motor Learning Purkinje cells only output from cerebellar cortex inhibit deep cerebellar nuclei Input to Purkinje cells Mossy fibers via parallel fibers • from spinal cord & brainstem nuclei climbing fibers • cerebral cortex & spinal cord • via inferior olivary nucleus ~ Cerebellum: & Motor Learning 1 Purkinje cell synapses.. 1 each with 200,000 parallel fibers Many with 1 climbing fiber • strong synaptic connections Climbing fibers effects of mossy fibers transient ~ Cerebellum: 3 layered cortex Molecular Purkinje Granule Climbing fibers Mossy fibers Cerebellum: & Motor Learning Long-term depression (LTD) requires concurrent activity climbing & parallel fibers active together in activity of specific Purkinje cells Climbing fibers may carry error signals corrections parallel fiber influence input specificity only affects active synapses of a parallel fiber ~ LTD Mechanisms Similar to LTP changes are postsynaptic Glutamate receptors ~ LTD Mechanisms Requires concurrent activity Climbing fiber 1. Ca++ influx - voltage-gated Parallel fibers activate 2. AMPA - Na+ influx 3. mGLUR1 AMPA desensitized Na+ influx ~ LTD Mechanisms mGluR1 metabotropic cGMP-mediated intracellular Ca++ stores activation of phosphatases Knockout mice lack mGluR1 loss of motor coordination ~