Hemiballismus results from the damage of which of the following regions of the brain?
Hemiballismus is a rare movement disorder that typically develops after a stroke involving the basal ganglia (specifically the subthalamic nucleus). It is usually characterized by involuntary flinging motions of the extremities. The movements are often violent and have wide amplitudes of motion. They are continuous and random and can involve proximal and/or distal muscles on one side of the body.
Hemiballismus is a rare movement disorder that typically develops after a stroke involving the basal ganglia (specifically the subthalamic nucleus). It is usually characterized by involuntary flinging motions of the extremities. The movements are often violent and have wide amplitudes of motion. They are continuous and random and can involve proximal and/or distal muscles on one side of the body.
Basal ganglia
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:-
- 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.
There are four main conditions to be aware of that result from problems with the basal ganglia:-
- Huntington's chorea (caudate nucleus)
- Wilson's disease (copper deposition in basal ganglia)
- Parkinson's disease (substantia nigra)
- Hemiballism (subthalamic nucleus)
