Left cerebral hemisphere: parts, characteristics and functions
The idea that the cerebral hemispheres present differences from one another is quite accepted, both in general culture and in more academic fields.
It is often said that the left hemisphere is the one behind logical and analytical areas, such as mathematics, while the artistic is related to the right hemisphere. It is also assumed that the right hemisphere controls the left side of the body, while the left does the same but with the right side.
Let's go deeper into left brain hemisphere, what characteristics are attributed to it and in what functions it is involved.
- Related article: "Parts of the human brain (and functions)"
What is a cerebral hemisphere?
Before talking in depth about the left hemisphere, we will first define what a cerebral hemisphere is. A hemisphere, from the Greek 'hemi' ('half') and 'sphera' ('sphere'), is each of the two main structures that make up the brain. Each hemisphere represents one of the two halves of the brain., one right and the other left.
These hemispheres are inverses of each other, but they are not symmetrical. The line that separates them is called the interhemispheric or longitudinal cerebral fissure, and in its deepest part there is a structure called
hard body, which connects both hemispheres.How is the left hemisphere of the brain structured?
Like its right-handed counterpart, The left hemisphere is anatomically structured into lobes., having half of each of them. These lobes are the frontal, parietal, temporal, occipital, and the insula.
As we have already mentioned, the corpus callosum, which is a structure with nerve fibers, connects both hemispheres to allow them to communicate. As with the other hemisphere, the left one is protected by the following layers:
- dura mater: It is the outermost membrane and closest to the skull.
- ArachnoidIt is between the dura mater and the pia mater.
- Pia materIt is the innermost membrane. It is contiguous with brain matter.
main features
Anatomically both hemispheres are very similar. Although, as we have already mentioned, they are not symmetrical, they are very similar. They have both fissures and gyri and both have the same number of lobes, as well as being similar in size.
However, they have different attributes. The left hemisphere is known to be the brain structure in charge of more than linguistic aspects, in addition to being behind analytical processing, typical of mathematics. Let's take a closer look at these features:
1. Symbolic
The left hemisphere is the person in charge of using symbols for the representation of both concepts and objects.
Thus, it is this hemisphere that allows us to understand that the symbol '+' means adding to something or more, or that the symbol ☮️ means peace.
2. Verbal
As we have already mentioned, the left hemisphere is the one that is involved in the use of verbalized language.
This means that it is the one behind such everyday and fundamental aspects of human communication such as speech, verbal memory, writing and reading.
3. Analytical
When we say that this hemisphere is analytical, we come to indicate that Its information processing is done by following a few steps that follow one another in a more or less linear way., analyzing each of the details of a certain situation or problem.
For this reason the left hemisphere acquires such great importance in mathematics, in which, for reach the solution, it is necessary to identify what are the steps to follow to have the answer correct.
Besides, is detailed and relatively objective when analyzing reality, allowing specific observations to be made and a specific thought, appropriate for the problem situation.
4. Temporary
Follow the passage of time, that is, arrange things in time sequences. It goes from start to finish.
5. Rational
The left brain hemisphere tends to enhance rational reasoning. That is to say, allows abstracting an explanation of reality from reason.
6. logical and linear
When it is said that the left hemisphere is logical, it means that it establishes causal relationships between different facts. Thus, a phenomenon must necessarily be caused by a prior or be responsible for a subsequent consequence.
This characteristic, together with the analytical aspect of this hemisphere, acquires great importance in solving mathematical problems.
Regarding the linear aspect, it comes to indicate that ideas are always linked to each other.
functions
These are the main functions of the left cerebral hemisphere.
Verbal language and mathematics
Related to both its verbal and symbolic capacities, the left hemisphere is able to identify groups of letters and interpret them as words which, in turn, make up groups of them and form meaningful sentences.
Thanks to this, it also plays an important role in speaking, writing, solving mathematical problems, numbering and logic.
Other aspects in which this hemisphere is significantly involved are verbal memory, grammar, organization of syntax, phonetic discrimination, planning, decision-making, long-term memory term...
- You may be interested in: "The 11 executive functions of the human brain"
Expression and understanding
John Hughlins Jackson, a neurologist, said at the time that the left hemisphere was the center of the faculty of expression. This means that this hemisphere is responsible for transforming a set of information into something meaningful.
So, this hemisphere stores concepts that it will later emit in the form of words, both oral and written, allowing to transmit ideas from the inside of the mind of one person to another through the use of verbal communication.
If an embolism occurs that affects this hemisphere, functional losses such as loss of speech can occur, in addition to motor skills on the right side of the body may be affected, since the left hemisphere controls that half bodily.
Relationship between both halves of the brain
Although we have commented that each hemisphere has its particularities and has its own functions, this is not It does not mean that they are radically different from each other, nor does it mean that they do not carry out activities in a different way. joint. What must be understood is that there are activities that are mainly carried out by one of the two hemispheres and others in which it is the task of its counterpart.
As a curiosity, the research indicates that interhemispheric differences are something distinctive of the human species. In most people, both hemispheres complement each other. Normally, verbal aspects such as speech are under the control of the left hemisphere, however, there are cases, especially in left-handed people, in which speech is an activity carried out by areas located on both hemispheres.
Furthermore, it has been seen that In situations in which there is a brain lesion, there may be changes in the location of certain functions. This 'transfer' of functions is especially significant in childhood, at which time, thanks to cerebral plasticity, the brain tries to 'save' a capacity of the injured area by making it another area, possibly from the opposite hemisphere, who becomes post.