9 14 MIT Spring 2009 Classes 33 34 Study Questions 1 What are the two outputs of the corpus striatum illustrated by Nauta and Feirtag Use this to explain the meaning of the statement that the major output of the extrapyramidal system is the pyramidal system 2 Contrast the major source of sensory inputs to the striatum in amphibians and mammals according to Striedter Similarly contrast the major output Note connections that are quantitatively smaller are neglected although they may be very important in understanding the evolution and functions of the striatum as noted in classes 3 Why do you think the major source of sensory input changed in mammals i e what were the benefits that encouraged the change from the amphibian condition Thinking along these lines what would you expect to be the major source of sensory input to the striatum in reptiles Check this in Striedter What about birds 4 What is the ansa lenticularis 5 The major satellites of the striatum are the substantia nigra and the subthalamic nucleus How are they connected to the striatum caudate and putamen globus pallidus 6 What is the limbic striatum What structures does it include and how does it differ from the non limbic striatum 7 Contrast different routes for sensory information to travel from primary sensory cortical areas e g visual cortex to motor output systems Use information from previous 9 14 sessions as well as the new information Try to describe at least three routes 8 Contrast the pathways to motor cortex and the pathways to the superior colliculus from the caudate putamen 9 What is the double inhibition of pathways through the striatum What neurotransmitter is involved 10 For an understanding of striatal function it is important to recognize the discovery of multiple parallel pathways with possibly opposing effects on movement Give an example 11 Why is it that basal ganglia disease causes hyperkinesias too much movement Give examples of such hyperkinesias and describe a possible mechanism underlying the disorder Questions on Olanow et al and on Kempermann and Gage 12 Why might the topographic organization of connections not be a critical factor in the functioning of nigrostriatal connections from transplanted tissue 13 Describe the critical nature of donor age in transplant procedures and why this might be expected 14 How can imaging of the living brain be used to assess transplant success 15 How has neuroanatomical assessment been done using tissue obtained at autopsy Describe a result 16 What problem does the size of the human corpus striatum pose for transplant procedures How far can axons grow from the transplants 17 How is locus of a transplant within the striatum related to possible functional effects 18 Why do you think that the functional improvements after transplants have such a slow onset and slow progression 19 What are one or two future alternatives to transplants of tissue from human fetal substantia nigra Supplementary 20 Chemoarchitectural studies have given two very different kinds of information about the caudate and putamen they have revealed a pattern in overall structural organization and also cell type differentiation What is the pattern and give examples of cell types according to chemical content Brodal box p 293 several figures MIT OpenCourseWare http ocw mit edu 9 14 Brain Structure and Its Origins Spring 2009 For information about citing these materials or our Terms of Use visit http ocw mit edu terms