MT4 Parkinson Disease.ppt

CEREBRAL CORTEX excitatory excitatory BASAL GANGLIA THALAMUS inhibitory Basal ganglia loops: inhibition of GPi - DIS-inhibtion of thalamus -excitation of SMA - initiation of voluntary movement CORTEX SMA Glu CAUDATE/PUTAMEN GABA Dopamine (+ve & -ve) GABA GABA SUBSTANTIA NIGRA GP interna...

CEREBRAL CORTEX excitatory excitatory BASAL GANGLIA THALAMUS inhibitory Basal ganglia loops: inhibition of GPi - DIS-inhibtion of thalamus -excitation of SMA - initiation of voluntary movement CORTEX SMA Glu CAUDATE/PUTAMEN GABA Dopamine (+ve & -ve) GABA GABA SUBSTANTIA NIGRA GP internal GP external Glu SUBTHALAMIC NUCLEI GABA THALAMUS Glu GP internal - internal (or medial) segment of globus pallidus GP external - external (or lateral) segment of globus pallidus Caudate putamen - neostriatum SMA - supplementary motor area (cortex) Red pathways: inhibitory Black pathways: excitatory 1 Dopamine modulation of both direct and indirect pathways promotes voluntary movement DIRECT PATHWAY CORTEX SMA Glu Dopamine (D1 receptor +ve) GPexternal CAUDATE/PUTAMEN GABA SUBSTANTIA NIGRA SUBTHALAMIC NUCLEI GPinternal GABA Glu THALAMUS INDIRECT PATHWAY CORTEX Dopamine (D2 receptor -ve) SMA Glu CAUDATE/PUTAMEN GABA GPexternal GABA SUBSTANTIA NIGRA GPinternal Glu SUBTHALAMIC NUCLEI GABA THALAMUS Glu 2 Parkinson’s Disease - reduced dopamine modulation CORTEX SMA Glu CAUDATE/PUTAMEN GABA GPexternal Dopamine (+ve & -ve) GABA GABA Glu SUBSTANTIA NIGRA GPinternal SUBTHALAMIC NUCLEI GABA THALAMUS Glu Surgical / DBS targets? CORTEX SMA Glu CAUDATE/PUTAMEN GABA Dopamine (+ve & -ve) GPexternal GABA GABA Glu SUBSTANTIA NIGRA GPinternal SUBTHALAMIC NUCLEI GABA THALAMUS Glu 3 Neuroanatomy Quiz answers on separate handout G A H B I C J * D E K F L Pale: A, B, E, F, H, I, J, K, L Dark: C, D, G 4