Mesocortical pathway: structures, functions and role in psychosis

Within the nervous system of the person inhabit hundreds of thousands of neurons that make up their networks and are responsible for transmitting both electrical impulses and certain substances from one side to other.

The mesocortical pathway that network of neurons found throughout the brain and that it exercises primordial control over thought, emotion, and feeling.

• Related article: "Parts of the human brain (and functions)"

What is the mesocortical pathway?

The route or bundle of neurons that connect the ventral tegmental area and the cerebral cortex, especially at the level of the frontal lobe, is known as the mesocortical pathway. The mesocortical pathway is one of the most important pathways of the dopaminergic system, having an extremely important role in cognition, as well as in emotions and affectivity.

Lesions or alterations in the mesocortical pathway are common in certain psychotic disorders as the schizophrenia, in which it is hypothesized that it is the cause of its cognitive and negative symptoms.

Within the dopaminergic system we also find other pathways whose main task is to transport dopamine from one place in the brain to another. The neurons that make up these pathways are formed by somas that synthesize dopamine, while the axons are responsible for transmitting it along the entire pathway.

These pathways that accompany the mesocortical pathway and form the dopaminergic system are:

• mesolimbic pathway.
• mesocortical pathway.
• nigrostriatal pathway.
• tuberoinfundibular pathway.

parts and structures

As mentioned above, the mesocortical pathway mainly involves the ventral tegmental area (VTA) and the cerebral cortex. Besides, this connection is made at the level of the frontal lobe.

1. frontal lobe

The frontal lobe is an area of ​​the cerebral cortex located in the anterior area of ​​the brain, its main characteristic that this is only fully developed in the most complex animals such as vertebrates, mainly hominids.

Among the functions of the frontal lobe are linguistic and oral production, as well as phono-articulatory movements. In addition, the frontal lobes have the very important mission of coordinating the executive functions. These functions are what give the ability to direct behavior, attention, planning, sequencing and reorientation of behavior.

• Related article: "What is the frontal lobe and how does it work?"

2. ventral tegmental area

This area, also known as the ventral tegmentum, is made up of a group of neurons located in the midline of the floor of the midbrain.

This area is the place of origin of the mesocortical dopaminergic pathway and its function is to regulate the natural reward system of the brain. Therefore, it has a fundamental role in motivation, pleasure and orgasm, the addictions, loving feelings and in some psychiatric disorders.

3. Cerebral cortex

The cerebral cortex, also called the cerebral cortex, is formed by the network of neurons that form the tissue that covers the extension of both cerebral hemispheres.

Its functions are focused on governing perception, imagination, thought and reason.

Its involvement in brain functions

Like the other dopaminergic pathways, the mesocortical pathway plays a highly relevant role in a series of essential brain functions for the mental health of the person.

These functions are cognition as an executive function on the one hand, and emotions and affectivity on the other.

1. Cognition

By cognition we understand the capacity that people have to treat the information they receive from the environment through perception, as well as the interpretation and meaning they give it.

Cognition is used in a large number of processes such as learning, reasoning, attention, memory, or problem solving.

• Related article: "Cognitive processes: what exactly are they and why do they matter in Psychology?"

2. Emotions and affectivity

An emotion is a psychophysiological response to a certain stimulus; either a person, a place or situation, an event or the person's own memories.

At a psychological level, emotions generate changes in attention and activate or inhibit certain behaviors. In addition, it also has the ability to strengthen important associations in memory.

As far as affectivity is concerned, while emotions are associated with a series of bodily reactions, affectivity and feelings are related to the mind. Likewise, unlike emotion, affectivity implies a process of interaction between two or more people.

• You may be interested in: "Emotional psychology: main theories of emotion"

Implication in psychotic disorders

Once the areas of action and functions of the mesocortical pathway are known, it is easier to understand why a decreased activity of this can lead to numerous symptoms characteristic of disorders psychotics.

Specifically, in schizophrenia hypofunction of the mesocortical pathway gives rise to cognitive and negative symptoms of this disorder.

negative symptomatology

The negative symptomatology characteristic of schizophrenia is that which is manifested by an impoverishment of personality and relationships and a deterioration of mood.

Within this symptomatology we can find three different subtypes: alterations in language, mood disturbances and a third subgroup with other symptoms that do not fit into the previous.

Language alterations

These symptoms include laconic speech, poor language and short answers, lack of language content and empty responses, blocking, and increased response latency.

mood swings

It manifests mainly with dullness or flattening of emotions, facial inexpression or fewer spontaneous movements.

Likewise, patients with negative symptoms show great inconsistencies between the feelings expressed and the situation that surrounds them. An example might be laughing at a funeral or crying at a joke.

Finally, other mood-related symptoms are inappropriate affect or ambivalence, a feeling of emptiness and the feeling of deep anguish.

other symptoms

Among the rest of the negative symptoms in which the mesocortical pathway is involved, we find apathy and apathy, anhedonia and unsociability, social maladjustment

cognitive symptoms

The cognitive symptoms of schizophrenia refer to concentration and memory problems, which are reflected in a lack of attention, slow thinking and lack of awareness of illness, either anosognosia.