FUNCTIONS OF THE BASAL NUCLEI

FUNCTIONS OF THE BASAL NUCLEI assist in the regulation of voluntary movement & the learning of motor skills initiate movement & modulation of motor cortex

HOW IS MOVEMENT INITIATED? BASAL NUCLEI DIRECT PATHWAY

BASAL NUCLEI INDIRECT PATHWAY

CLINICAL CONSIDERATIONS INVOLVING THE BASAL NUCLEI

DISORDERS OF THE BASAL NUCLEI Hyperkinetic disorderHypokinetic disorder Excessive and abnormal movementsLack or slowness of movement Result of excessive activity in dopaminergic nerve fibers Result from lack of dopamine in basal ganglia circuits e.g. athetosis, hemiballismus, choreae.g. Parkinson’s disease

DISORDERS OF THE BASAL NUCLEI Hyperkinetic disordersHypokinetic disorders Excessive and abnormal movementsLack or slowness of movement Result of excessive activity in dopaminergic nerve fibers Results from lack of dopamine in basal ganglia circuits e.g. athetosis, hemiballismus, choreae.g. Parkinson’s disease

HYPERKINETIC DISORDERS

CHOREA

patient exhibits involuntary, quick, jerky, irregular movements that are nonrepetitive Huntington’s Disease Sydenham’s Chorea

HUNTINGTON’s DISEASE traced to a single gene defect on chromosome 4 - encodes the protein, huntingtin - CAG codon which codes for glutamine is repeated

HUNTINGTON’s DISEASE an autosomal dominant neurodegenerative disorder affecting the basal ganglia - caudate nuclei

SYDENHAM CHOREA associated with rheumatic fever streptococcal bacteria antigens are similar in structure to the proteins in the membranes of the striatal neurons

SYnDEHAM CHOREA associated with rheumatic fever streptococcal bacteria antigens are similar in structure to the proteins in the membranes of the striatal neurons

SYDENHAM CHOREA HUNTINGTON’s DISEASE

HYPERKINETIC DISORDER

HemiBallismus a form of involuntary movement confined to one side of the body the patient limbs suddenly fly about out of control in all directions lesion occurs in the opposite subthalamic nucleus or its connections

HYPERKINETIC DISORDER

ATHETOSIS consists of slow, sinuous, writhing movements that most commonly involve the distal segments of the limbs degeneration of the globus pallidus

HYPOKINETIC DISORDER

PARKINSON’s DISEASE a progressive disease of unknown cause commences between ages years associated with neuronal degeneration in the substantia nigra

PARKINSON’s DISEASE a progressive disease of unknown cause commences between ages years associated with neuronal degeneration in the substantia nigra

REFERENCES Snell, R. S. (2010). Clinical neuroanatomy (7th ed.). Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins. Thaleschou. (2015). 2-Minute Neuroscience: Basal Ganglia [Video File]. Retrieved from