We explain the anatomy and functions of this lobe of the human brain.
The frontal lobe is one of the four lobes into which the human brain is divided . This is of outstanding importance, since it develops executive functions, related to problem solving, mental flexibility, attention and working memory.
It is also involved in movement and the expression of language. In this article we will learn what areas it is divided into, what its functions are and what an injury implies in each of its different parts.
- Recommended article: “Human brain: its parts and main functions”
What is the frontal lobe?
The human brain is divided into four lobes: the occipital, parietal, temporal, and frontal . Each lobe is responsible for certain functions, and is located in a specific area of the brain; on the other hand, the lesion of each lobe implies some alterations or others. That is, each of these divisions is specialized in one or more specific fields.
The frontal lobe is the lobe that is roughly related to executive functions, control of behavior and movement. For its part, executive functions encompass those processes aimed at processing and organizing information properly, such as planning or organization.
In addition, they also encompass other types of more adaptive processes, such as decision-making or conflict resolution. The frontal lobe, in turn, includes an even more specific area of the brain: the cortex or prefrontal area. This lobe is the most primitive area of the brain, and the one that originates first at the anatomical level.
Functions
What are the functions of the frontal lobe? The functions are very diverse, and are located in different parts of the same lobe.
Let’s see the most important areas of the frontal lobe and the functions in which they are involved:
1. Motor cortex
The motor cortex is located in the frontal lobe of the brain, and its functions are related to the control of voluntary movements made by the person . Voluntary movements encompass not only the extremities, as is commonly thought, but also the articulation of expressive language and eye movement.
Within this cortex we also find Broca’s area, considered the “center of expressive language”. This area allows the articulation and expression of language; on the other hand, it is also involved in the movements that allow writing.
2. Prefrontal cortex
The prefrontal cortex is vitally important in brain development; in fact, they consider it its maximum expression, and the most primitive area, as we have already seen. This cortex is involved in the development of cognitive and executive functions . Cognitive functions are higher order functions, controlling behavior and emotions.
Cognition is related to attention, different types of memory, problem solving, mental flexibility, etc. On the other hand, the prefrontal cortex receives information from the limbic system ( related to emotions ).
injuries
Injuries to the frontal lobe can originate from various causes, but basically they are caused by head injuries (TBI), which are fortuitous blows to the head that cause it to shake in such a way that it can cause major fractures at the cranial level. These types of blows will obviously affect the brain and its functioning.
Frontal lobe lesions cause symptoms basically of behavioral disinhibition ; thus, a person with a lesion in the frontal lobe will have lost that “social filter” that tells him when and how he should act when he is in society, and when and how he should not do it because it could harm him or he would be frowned upon socially.
However, we can further specify the areas of frontal lobe injury and its effects.
1. Lesions in the motor areas
These areas include the primary motor area and the premotor area. An injury to them can cause significant deficits in learning and movement execution.
2. Left frontal lobe lesions
A lesion in this area can cause Broca’s aphasia, language difficulties, apraxia (inability to perform movements for any purpose) and agraphia.
Specifically, Broca’s aphasia is a well-known and quite common language disorder, characterized by difficulties in producing language, as well as other symptoms such as anomaly, agrammatism and repetitive language. However, comprehension is usually preserved quite well.
3. Prefrontal lesions
Lesions in the prefrontal area of the frontal lobe, already mentioned, usually lead to alterations in executive functions and working memory (the latter allows us to manipulate and use information in different tasks).
On the other hand, the injury also usually causes an alteration in prospective memory (that memory that allows us to remember “plans or tasks that we must do”, such as a meeting that we have in 15 days).
3.1. prefrontal syndromes
Within the prefrontal lesions, in addition, we find three types of prefrontal syndromes (or alterations) that the following may appear.
3.1.1. dysexecutive syndrome
This syndrome appears due to lesions in the dorsolateral region of the prefrontal area. Dysexecutive syndrome causes an inability to generate new hypotheses, as well as difficulties in solving complex problems. The patient also shows low mental flexibility that is evident when you present him with certain tasks or when he tries to change his attention focus.
In addition, he tends to be persevering, getting stuck on the same subject. At a verbal level, his fluency in speech is reduced, and he also has a significant attention deficit; You have trouble concentrating and are easily distracted.
On the other hand, Dysexecutive Syndrome can also generate important emotional alterations, as well as motor difficulties, since, as we have seen, the frontal lobe is also involved in movement. Thus, the person becomes more “robotic” to think and reason, colder.
3.1.2. pseudodepression
In pseudodepression, also caused by a prefrontal lesion, specifically in the medial cingulate region of the prefrontal cortex, symptoms of apathy and loss of initiative and energy (abulia) appear. The person moves more slowly (hypokinesia), speaks less (hypolalia), has difficulty planning and also has alexithymia (is unable to identify emotions).
That is to say, in pseudo-depression the person tends to be very depressed and the functions go “less”.
3.1.3. pseudopsychopathy
Pseudopsychopathy appears due to a lesion in the orbitofrontal region of the prefrontal cortex. This clinical picture causes symptoms of altered personality and emotions , as well as great impulsiveness and disinhibition. The patient is also irritable, ecopraxic (makes obscene gestures), sometimes euphoric (or moria; that is, superficially euphoric), and hyperkinetic (moves around a lot).
On the other hand, his social judgment of reality is impaired, and he may act inappropriately socially (in public). In addition, in this case, unlike in the previous table, the symptomatology is more of “excess”.
Bibliographic references
- Carlson, N. (2005). Physiology of behavior. Madrid: Pearson Education.
- Navas-Collado, E. and Munoz-Garcia, JJ (2004). The dysexecutive syndrome in psychopathy. Rev Neurol, 38(6): 582-590.
- Netter, F. (1989). Nervous system. Anatomy and physiology. Barcelona: Salvat.
To the classic question “what do you do?” I always answer “basically I am a psychologist”. In fact, my academic training has revolved around the psychology of development, education and community, a field of study influenced my volunteer activities, as well as my first work experiences in personal services.