One of our most impressive brain structures is the black substance, if we judge it by its size, we might think it doesn’t play an important role, when it’s actually fundamental to our organization.
This article will be dedicated to him. We will define it and talk about its parts and functions, in addition, we will show you what diseases may be associated with changes in the black substance.
- It is a structure that is part of the grey central nuclei.
- A circuit of interconnected nuclei.
- Is found in the mesencephaly of our brain.
- In addition we have it on both sides of our brain.
- In each of our brain hemispheres.
You may be wondering what it is called for, the neurons of this structure have a pigment that darkens it; This pigment, called neuromelanin, is present in dopaminergic neurons, which are very abundant in this region.
The black substance consists of two parts, each with its own functions:
Don’t think that, as in its compact part there are more dopaminergic neurons, the crosslinked section does not play an essential role, mainly helping to inhibit neuronal by the neurotransmitter GABA.
The black substance is associated with the learning process because it is involved in the brain’s response to stimuli, its function is to facilitate learning thanks to the reinforcing effects of dopamine, in addition, it is mainly involved in spatial learning.
Why this feature? A lot of dopaminergic neurons are activated when stimuli surprise us. This would support the participation of this structure, as it contains such neurons. However, it does not do so in isolation, it works in relation to other brain structures.
As we mentioned at the beginning, the black substance is part of the central grey nuclei, a set of nuclei that influence movement, so what is the specific action of the black substance?Initiate and direct movements that require fine motor skills.
Eye movements influence the activation of the crosslinked part in association with the thalamus and other structures of our nervous system, acting above all so that our gaze stabilizes, in the movements of the face and head, in addition, intervene in visual processing.
When we feel pleasant sensations, the neurons of the black substance are also activated, in this way they participate in reward circuits, according to Bear, Connors and Paradiso, authors of the book?Neurosciences, brain exploration, facilitate the prediction of behaviors that involve strengthening.
Then, when behavioral patterns are repeated, the black substance also acts, this is due to the associations between stimuli and reactions, so this substance is related to motivation, reinforcements and addictions, as it can be triggered in adaptive situations. use of learning.
Again, we are talking about dopaminergic neurons found elsewhere in this structure, thanks to which we regulate our biological sleep rhythm, that is, they are linked to sleep-wake patterns, the sleep phase in which they are most active is the REM Phase.
In addition to these functions, the black substance is related to time processing, i. e. its perception of the detection of stimulus intervals.
As we can see, the black substance acts in several important functions for our body, so failure can lead to several diseases, let’s focus on the two most important:
In short, the black substance is what helps us with movement, motivation, sleep, detection of stimulus intervals, mood, learning and connection of nerve signals. Therefore, its absence or alteration poses important problems in the processes in which it participates.