Cerebral hemisphere

The idea that the cerebral hemispheres are different from each other is widely accepted, both in general culture and in more academic settings. 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. In this article we will provide you information about the Left cerebral hemisphere.

We are going to go into more depth about the left cerebral hemisphere , what characteristics it is attributed and in what functions it is involved.

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 inverse 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 the corpus callosum , that connects both hemispheres.

How is the left hemisphere of the brain structured?

Like its right counterpart, the left hemisphere is anatomically structured in lobes , having half of each of them. These lobes are the frontal, parietal, temporal, occipital, and 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 is protected by the following layers:

• Dura mater : it is the outermost membrane and closest to the skull.
• Arachnoid : it is between the dura mater and the pia mater.
• Pia mater : it is the innermost membrane. It is contiguous with brain matter.

Characteristics

Anatomically both hemispheres are very similar. Although, as we have already mentioned, they are not symmetrical, they are very similar. They present both fissures and convolutions and both have the same number of lobes, in addition to being similar in size.

However, they have different attributes. The left hemisphere is known to be the brain structure in charge of the linguistic aspects, in addition to being behind the analytical processing , typical of mathematics. Let’s take a closer look at these features:

1. Symbolic

The left hemisphere is responsible for using symbols to represent 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 commented, 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 as speech, verbal memory, writing and reading.

3. Analytical

When we say that this hemisphere is analytical, we mean that its information processing is done by following steps that follow one another in a more or less linear way , analyzing each of the details of a given situation or problem.

For this reason, the left hemisphere acquires such great importance in mathematics, in which, in order to reach the solution, it is necessary to identify the steps to follow in order to have the correct answer.

In addition, it is detailed and relatively objective when it comes to analyzing reality , allowing specific observations to be made and proposing a specific thought, appropriate for the problem situation.

4. Temporary

Follow the passage of time, that is, order things in temporal sequences . It goes from beginning to end.

5. Rational

The left cerebral hemisphere tends to enhance rational reasoning. That is, it allows abstracting an explanation of reality from reason .

6. Logical and linear

When the left hemisphere is said to be logical, it means that it establishes causal relationships between different events. 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.

As for the linear aspect, it comes to indicate that ideas are always linked to each other .

Features

These are the main functions of the left brain hemisphere.

1-Verbal language and mathematics

Related to both its verbal and symbolic abilities, the left hemisphere is capable of identifying groups of letters and interpreting them as words that, in turn, form groups of them and form meaningful sentences.

Thanks to this, it also plays an important role in speech, writing, mathematical problem solving, numbering and logic .

Other aspects in which this hemisphere is notably involved are verbal memory, grammar, syntax organization, phonetic discrimination, planning, decision-making, long-term memory …

2-Expression and understanding

John Hughlins Jackson, a neurologist, said at the time that the left hemisphere was the center of the power of expression. This means that this hemisphere is in charge of transforming a set of information into something with meaning. Left cerebral hemisphere characteristics

Thus, this hemisphere stores concepts that it will later emit in the form of words , both oral and written, allowing ideas from inside the mind to be transmitted from 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 may occur, in addition to affecting motor skills on the right side of the body, since the left hemisphere controls that half of the body.

Relationship between both halves of the brain

Although we have commented that each hemisphere has its peculiarities and has its own functions, this does not mean that they are radically different from each other or that they do not carry out activities together. What must be understood is that there are activities that are carried out mainly 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 exerted by areas located in both hemispheres.

In addition, it has been seen that, in situations in which a brain injury occurs, there may be changes in the location of certain functions . This ‘transfer’ of functions is especially significant in childhood, at which time, thanks to brain plasticity, the brain tries to ‘save’ its own capacity from the injured area, making it another area, and it may be from the opposite hemisphere, whoever does it. position.