Lesion of Globus pallidus causes -

Ans. is 'c' i.e., Athetosis Diseases of Basal gangliao Three distinct biochemical pathways in the basal ganglia normally operate in a balanced fashion : - 1 ) Nigrostriatal dopaminergic systemQ; 2) Intrastriatal cholinergic system; 3) GABAergic system which projects from the stratum to globus pallidus and substantia nigra.o When one or more of these pathways become dysfunctional, characteristic motor abnormalities occur. There may be two types of disorder: -Hyperkinetic: - There is excessive and abnormal movement, e.g., Chorea, athetosis and ballism.Hypokinetic : - There is paucity of movement, e.g., Akinesia and Bradykinesia.o The classical example of Basal ganglia disease is Parkinsonism in which there is degeneration of dopaminergic neurons in the substantia nigra pars compacta. The fibers to putamen are most severely affected. A patient with parkinsonism have both hypokinetic and hyperkinetic features : -Hypokinetic : - Bradykinesia, AkinesiaHyperkinetic : - Cogwheel rigidity, Resting tremorQ.DiseasePart of Basal ganglia involvedParkinsonismSubstantia nigra pars compacta - Nigrastriatal pathwayHuntington choreaStriatum (mainly caudate nucleus; may be putamen)BallismSubthalamic nucleiAthetosisGlobus pallidus (mainly)Q and Subthalamic nucleus.