Abnormal cerebral morphology Abnormal basal ganglia morphology Abnormality of the basal ganglia HP:0006952 Anomaly of the basal ganglia SNOMEDCT_US:70835005 HP:0007257 The basal ganglia are a group of nuclei (striatum, pallidum substantia nigra, and the subthalamic nucleus) at the base of the forebrain that are connected to the cerebral cortex, the thalamus, and other areas. The basal ganglia subserve motor functions that are distinct from those of the pyramidal (corticospinal) tract, for which reason neurologic abnormalities caused by lesions to the basal ganglia are often referred to as extrapyramidal. HP:0002134 Abnormality of the basal ganglia. UMLS:C0004782 Basal ganglia disease