The basal ganglia are a group of structures that regulate balance, posture, eye movements and stimulus to movements. They are closely connected to other motor areas in the brain and connect the thalamus to the motor cortex.
It is the place in the brain where automatisms in movements are organized, such as driving, cycling, knitting, standing upright (keeping balance), walking.
In adults, postural reflexes are stored here.
The basal ganglia are also involved in stimulation in learning simple processes.
The basal ganglia are involved in cognition and emotion and play an important role in 'reward and reinforcement' of behavior, 'response to a stimulus', addictive behavior and habit formation.
Recent research has shown that changes in caudate nucleus / basal ganglia can explain fatigue in MS and traumatic brain injury.
The combination of postural problems in the basal ganglia is called parkinsonism because they are reminiscent of Parkinson's disease.
- Altered gross and fine movement pattern, delayed movement
- Difficulty talking, word-finding problems
- Difficulty with posture and movements
- Tremors; shake and vibrate
- Involuntary movements, spasms
- Increased muscular tension, muscle stiffness
- Abnormal body posture
- Difficulty with balance and difficulty walking
- Difficulty seeing caused by not being able to steer the eye movement
- Difficulty in starting a movement, staying in motion and stopping a movement
- Uncontrolled repeated movements, for example, tics, uttering cries.
Where in the brains?
The basal ganglia is an area centrally located at the bottom of the brains. There are multiple and confusing names for the components of the basal ganglia.
- Caudate nucleus; has the function to pass on all kinds of information from other areas of the cortex through the putamen and the globus pallidus to the thalamus, after which it ends up in the frontal cortex (cortical areas). The corpus striatum can be divided into the dorsal and ventral striatum. Certain parts of the caudate and putamen nucleus are also counted as part of the striatum ventral.
- Putamen is, among others, involved in the regulation of motor skills,
- Globus pallidus,
- Substantia nigra provides the basal ganglia of dopamine,
- Subthalamic nucleus
The pre-motor cortex gives the signal 'ready' and the basal ganglia /thalamus give the signal 'go' to the motor cortex.
Lim S-J, Fiez JA and Holt LL [CC BY 3.0 (https://creativecommons.org/licenses/by/3.0)], via Wikimedia Commons
The basal ganglia are involved in the following conditions and circumstances:
- Carbon monoxide poisoning
- Drug overdose
- Brain injury / stroke
- Liver disease
- Metabolic problems
- Poisoning with copper, manganese, or other heavy metals
- Side effects of medication
- Huntington's disease
- Multiple System Atrophy MSA
- Parkinson's disease
- Progressive Supranuclear Palsy PSP
- Wilson's disease
In the case of the hereditary Huntington's disease, cells in the basal ganglia die at a fast pace. This is accompanied by involuntary movements (over-mobility).
In the case of Parkinson's disease, the basal ganglia no longer receive dopamine from the substantia nigra, as a result of which the patient can move less well.
The list may not be comprehensive.
Jankovic J. Movement disorders. In: Daroff RB, Fenichel GM, Jankovic J, Mazziotta JC, eds.Bradley's Neurology in Clinical Practice. 6th ed. Philadelphia, PA: Elsevier Saunders; 2012: chapter 71
Lang AE. Parkinsonism. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, PA: Elsevier Saunders; 2011: chapter 416
Lang AE. Other movement disorders. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, PA: Elsevier Saunders; 2011:chapter 417