The human brain is a marvel of the human body. The complex system even its tiniest structures enable humans to lead a functional life and differentiate it with other mammals. This makes humans the most capable species on earth as humans possess a high level of intelligence and cognitive function to be living in a social setting. In this DoctorOnCall’s article, we would be talking about one of the structures of the human brain which plays a significant role in a human life, the basal ganglia.
The basal ganglia or known as the basal nuclei, is a group of brain structures located deep within the white matter of the brain, specifically the cerebral part. The white matter of the brain functions as protecting the nerve cells from damages and helps to send information to the brain rapidly. Basal ganglia are involved in many brain functions of forming connections in sending signals for part of the brain to work simultaneously including cognitive and emotion. Although, it is most commonly associated with the brain controlling the body’s movement. However, contributions of the basal ganglia in movement are complicated and up till now is not fully understood. Thus, experts are still studying the basal ganglia to make new discoveries.
The basal ganglia work by allowing or declining movement signals coming from the brain. It helps filter incorrect or unnecessary signals. Hence, this allows a person to control certain muscles without involving other muscles nearby to move. It helps specify and control the fine details of learned motor skills. Basal ganglia also receive sensory information such as sight, smell, taste, sound and touch to help refine the movements. Another function of the basal ganglia is to help humans learn better and form habits through evaluation from observation regarding life matters and processing signals that affect a person’s emotions and motivation.
Damages to the basal ganglia certainly makes a person unable to function properly. Some damages may make a person have a miserable life and the need to get support or care from their loved one or the society. There are many disorders affecting the basal ganglia when it is damaged. Do note that symptoms associated with damaged basal ganglia can be manifested into few medical conditions that seem similar. Thus, if you find yourself or someone you know exhibit such symptoms, do get medical advice and never diagnose yourself. Examples of damaged basal ganglia are:
1) Parkinson’s disease
This disease is common in the elderly, especially in male. It is caused by the progressive loss of nerve cells in part of the brain called the substantia nigra. This causes functional changes affecting the basal ganglia function. Parkinson’s disease is best spotted when a person has uncontrollable repetitive movement of tremor in the hands, arm, legs, jaw or head, muscle stiffness, movement becoming slow and imbalance or incoordination causing them to easily fall.
Repetitive movement that is small and random with sudden transition from one part of the body to another. Sometimes it may evolve to aggressive flinging of the arm called hemiballismus which tends to be wider and more vigorous.
It is an uncontrollable and abnormal movement affecting any part of the body including face, vocal cords, arm, trunk and legs. This may exhibit symptoms such as facial spasm, uncontrollable twisting of the neck and uncontrollable blinking.
4) Obsessive-Compulsive Disorder (OCD)
The basal ganglia are connected to the part of the brain controlling behaviour; the prefrontal cortex. Injury to these structures cause excessive thoughts and repetitive behaviours such as in OCD.
Damages to the basal ganglia cause alteration in the dopamine system of the brain. Usage of antipsychotic drugs aims to elevate the function of the basal ganglia.