Basal Ganglia

Question 1

The basal ganglia are a group of subcortical structures. Its main function is the control of movement but it may also play a part in some cognitive processes.

The components of the basal ganglia are as follows:-

Answer 1

Striatum (caudate, putamen, nucleus accumbens)
Subthalamic nucleus
Globus pallidus
Substantia nigra (divided into pars compacta and pars reticulate)

The putamen and globus pallidus are collectively referred to as the lenticular nucleus.

The connections of the basal ganglia are complicated but put simply, the cortex projects to the striatum, the striatum to the internal segment of the globus pallidus, the internal segment of the globus pallidus to the thalamus and the thalamus back to the cortex, thus creating a loop.

Question 2

There are four main conditions to be aware of that result from problems with the basal ganglia:-

Answer 2

Huntington’s chorea (caudate nucleus)
Wilson’s disease (copper deposition in basal ganglia)
Parkinson’s disease (substantia nigra)
Hemiballism (subthalamic nucleus)