There are many folds in our brain, specifically our cerebral cortex. The so-called brain turns are, along with the furrows that accompany them, one of the things that attracts the most attention when we observe a brain from the outside, giving it a wrinkled appearance that nevertheless allows the brain matter to be a compact mass.
These turns are not merely aesthetic: as the brain matter they are, they participate in the various functions carried out by our cortex. In this article we’ll see what brain spins are and review the characteristics of some of the best known ones.
What is a brain twist?
Let’s start with a definition of what a brain twist is. We call brain spins a set of folds visible in our cerebral cortex , generated by folding over itself as the brain develops and allowing the brain to be larger, making the space it occupies much smaller than would be expected if it had been extended.
Also known as gyres, the brain turns would be the part of the fold that protrudes, with the parts that remain inside being the grooves. These structures are formed throughout the brain development of the fetus, not possessing them from the beginning. Little by little they will be observed more and more, until their presence can be observed along the entire cerebral cortex.
These are protrusions of brain matter, specifically of grey matter . This implies that the brain turns are mainly formed by glial cells and somas of neurons, which are the part of the neuron that emits the information that will later be sent through the axon to the next neuron or target organ.
Main brain turns
Taking into account that they occupy the entire surface of the cerebral cortex, we must consider that there is a great amount of brain spinning. Each of them has different functions in the system . We will now comment on some of the most important and well-known ones, although we must bear in mind that there are many more than those presented in this article.
1. Pre-central turn
Also called pre-Rollandian convolution, this turn is located in front of Roland’s fissure (that is, it would be more towards the face than the said fissure). The brain matter that forms part of it corresponds to the primary motor area.
2. Post-Central Turn
Unlike the pre-central one, the post-central gyrus is located after or after Rolando’s cleft. In this occasion, we would be in front of a cerebral gyration that would be part of the primary somatosensorial cortex , linking itself to somatic perception and body sensitivity.
3. Toothed wheel
Circumvolution present in the lower part of the temporal lobe and forming part of the hippocampal formation, connecting it to the rest of the cortex. Specifically, it acts as a bridge between the entorhinal cortex and the hippocampus . Its functions are linked to memory, spatial navigation and the integration of emotion into memories.
4. Cingulate Turn
Like the previous one, this important brain twist has an important role in the integration and connection of the limbic system and the cerebral cortex . Located near the corpus callosum, it is associated with the perception of anxiety, pleasure, fear, the initiation of goal-oriented behavior, voluntary movement, voice modulation or the direction of attention and motivation.
5. Angular rotation
This is one of the best known brain turns, especially because of its involvement in language and mathematics. It helps to enable the production and understanding of meaningful sentences, as well as the understanding of written language. It is also involved in arithmetic ability and the interpretation of quantities, in addition to being linked to aspects such as behavioural control, symbol coding and creativity .
6. Supramarginal turn
Present in the parietal lobe above Silvio’s fissure, this is another of the best known brain turns. One of the functions for which it is best known is its involvement in enabling the ability to read and write , integrating information from the visual and auditory pathways. Working memory or tactile perception are also influenced by this gyrus.
7. Parahipocampal turn
With an important role in memory, the parahippocampal gyrus can be found around the hippocampus. The function most associated with this turn is that of storing and retrieving the stored information .
8. Fusiform turn
The fusiform gyre, which lies between the temporal and occipital and which can be divided into two sub-gyres called the lateral and medial occipitotemporal gyre, seems to be involved in aspects such as visual recognition of words and faces , as well as the processing of colour information or the differentiation between memory and non-rememberance.
It is also associated with category identification, deduction and understanding of figurative language.
9. Tongue twisting
This brain turn is located next to the parahippocampal and is in contact with the lateral and calcarine grooves, having a relevant role in the processing of visual information and the transformation of graphic information into auditory information in reading .
As we have mentioned so far, these are just a few of the many different twists and turns present in the brain. In addition to the above we can find, among others, the following.
- Island turns: Long and Short.
- Occipital turns.
- Upper front turn.
- Medium front turn.
- Lower front turn .
- Temporary superior turn.
- Average time shift.
- Temporary lower rotation.
- Supracellar turn.
- Orbital turn .
- Triangular turn.
- Opercular rotation.
- Straight turn.
- Olfactory turn .
- Pre-cuneiform gyrus.
- Cuneiform turn.
- Paraterminal turn.
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