Brain Network System

Introduction

 

The numerous cellular pathways of the brain comprise the brain network system that’s responsible for the control and regulation of all processes in the cerebral cortex. In order to relay the electrical or chemical impulse to a dedicated brain area, the information-carrying neuron cell connects with a vast number of other neurons, thus creating a brain network system.

What Is the Function of the Brain Network System?

 

The main function of this complex network made of neuron cell bodies, nuclei, neural circuits, and cortical processing areas is the transmission and translation of the information gained from the sensory stimuli via specialized patterns created between the neurons in the brain.

Anatomy of the Brain Network System

 

The sensory information received via the senses of smell, sight, touch, taste, and hearing, is transmitted to the brain processing areas via a predefined pattern of interconnected neural cells. These neurocognitive patterns are labeled according to their connections with the sensory or motor systems of the cerebral cortex.

 

The list of major brain network systems consists of the following functional neural patterns:

  • Default mode brain network;
  • Ventral attention brain network;
  • Dorsal attention brain network;
  • Frontoparietal brain network;
  • Salience brain network;
  • Visual brain network;
  • Limbic brain network.

Default Mode Brain Network

The default mode brain network encompasses cortical regions that are activated when the brain is not performing any complex cognitive processes during the wake phase.

Structure of the Default Mode Brain Network

This brain network comprises the following cortical structures:

 

What Is the Function of the Default Mode Brain Network?

 

The processes that activate this brain network include:

  • Day-dreaming;
  • Recalling and retrieval of memories;
  • Active imagining of the future;
  • Mental planning;
  • Mind-wandering;
  • Analyzing and understanding emotions in a given situation;
  • Empathy;
  • Coming to a conclusion about a moral situation;
  • Thinking about one’s personal emotions and character traits.

 

 

When there are no stimuli from the external environment, this default brain network is inactive.

Ventral Attention Brain Network

The neuronal network that connects parts of the brain involved in directing attention toward targeted information is labeled as a ventral attention network of the brain. The sensory information that has an effect on behavior usually is the focus of attention when it appears suddenly.

 

 

Structure of the Ventral Attention Brain Network

This network is made up of the following cortical areas:

  • The temporoparietal junction;
  • The ventral frontal cortex;
  • The visual cortex.

 

What Is the Function of the Ventral Attention Brain Network?

 

This network of interconnected cortical areas reorients attention to the unexpected event by relaying information via its predefined neuronal patterns. The reflex that is triggered as a response is transmitted via the reflex arcs that react to the sensory stimuli even before the electrical impulse gets to the dedicated brain area.

 

What Reflexes Are Triggered in the Central Nervous System?

Among the large number of reflexes triggered as a response to the sensory stimuli, we can distinguish:

  • The pupil-light reflex;
  • The cough reflex;
  • The scratch reflex;
  • The sneeze reflex;
  • The startle reflex;
  • The sucking reflex (in newborn babies);
  • The vestibulo-ocular reflex;
  • The blinking reflex.

 

Dorsal Attention Brain Network

 

The dorsal attention network is a sensory brain network system that is activated when there are clues of where, when, and to what the person voluntarily reorients attention.

 

Structure of the Dorsal Attention Brain Network

The intraparietal sulcus and the frontal eye fields located in both the upper frontal sulcus and the precentral sulcus comprise the dorsal attention network of the brain.

 

What Is the Function of the Dorsal Attention Brain Network?

This brain network plays a significant role in:

  • Selective attention;
  • When we try to reach for something;
  • When we want to grasp something;
  • Processing of learned instruction on how to use other objects.

 

Frontoparietal Brain Network

The frontoparietal network of the brain is also labeled as the central executive network because it’s activated during some of the most complex cognitive processes and demanding goal-oriented mental tasks.

 

 

Structure of the Frontoparietal Brain Network

This brain network involves a large number of cortical structures:

  • The prefrontal cortex;
  • The front lower part of the parietal lobe;
  • The cingulate gyrus located in the middle of the cerebral cortex;
  • The upper part of the precuneus;
  • The upper middle part of the thalamus;
  • The caudate nucleus.

 

What Is the Function of the Frontoparietal Brain Network?

This type of brain network supports:

  • Goal orientations;
  • Motivation;
  • Learning;
  • Cognitive practices;
  • Problem-solving;
  • The formation of working memory;
  • Decision making;
  • Organizational abilities.

 

Salience Brain Network

The neuronal network that connects parts of the brain involved in the coordination and selection of the stimuli that have primary importance for encoding and execution is labeled as a salience network of the brain.

 

 

Structure of the Salience Brain Network

This network consists of:

 

What Is the Function of the Salience Brain Network?

The salience network of the brain supports:

  • The processing of emotions;
  • Self-awareness;
  • The process of communication;
  • Determining the modes of social behavior;
  • Integration of the sensory information and emotional stimuli.

 

Visual Brain Network

The visual brain network is responsible for the transmission of electric impulses that carry information gained from the sense of sight to the corresponding processing areas in the cerebral cortex. It’s activated by a visual task, such as determining the distance between the viewer and the object, the depth of the visual field, the pattern of the object, etc.

 

 

Structure of the Visual Brain Network

During the processing of the visual information gained from the retina of the eye, this network connects the following cortical structures:

  • The geniculate nucleus of the thalamus;
  • The primary visual cortex (it’s housed in the occipital lobe);
  • Optic nerve (CN II).

 

What Is the Function of the Visual Brain Network?

The decoding and consolidation of visual stimuli by the processes following the visual neuron pattern in the brain enables us to give meaning, form, shape, color, depth, and structure to the items we see.

 

 

Limbic Brain Network

The limbic brain network is one of the most complex neuronal patterns in the brain. This neural system of the brain is activated as a response to stimuli that trigger our emotions and support reinforcing behavior.

 

 

Structure of the Limbic Brain Network

The network responsible for relaying information to the structures of the limbic system consists of:

  • The fornix;
  • The cingulate cortex;
  • The structures located in the middle part of the prosencephalon;
  • The hippocampus;
  • The hypothalamus.

 

What Is the Function of the Limbic Brain Network?

The limbic neuronal patterns serve as a relay network of information supporting memory, emotions, learning, and motivation. The information relayed by the limbic brain network also influences the function of both the endocrine and the autonomic nervous system of the body.

 

 

What Are the Other Brain Network Systems?

The following neural patterns are incorporated into a vast array of brain network systems:

  • The visual imagery network;
  • The attention network;
  • The right executive network;
  • The cerebellar network;
  • The spatial attention network;
  • The sensorimotor network;
  • The somatomotor network;
  • The auditory network;
  • The motor network;
  • The resting-state networks.

 

Fun facts

Did you know?

  1. The human brain is the most powerful information processing system of all other computer systems invented in human history.
  2. The science of brain network systems comprises several other disciplines, such as cognitive psychology, behavioral neuroanatomy, neurophysiology, and neuroimaging.
  3. Cognitive psychology studies the cognitive processes such as learning, attention, memory, etc.
  4. Behavioral neuroanatomy is a branch of neurology. It studies the effects of dysfunctional parts of the brain (neurological syndromes and diseases) on the behavior of the affected individual.
  5. Neurophysiology is involved in scientific research on how the cortical structures function.
  6. Every cortical structure in the brain is one information processing system dedicated to special types of cognitive or motor functions.
  7. Breathing is an involuntary process that can also be labeled as a reflex action.
  8. The palmar grasp reflex occurs in infants. They will instinctively grasp any object placed in their palm.
  9. The gag reflex is triggered upon touching the back of the throat or the tongue.
  10. If the salience network is dysfunctional, it may result in a wide range of neurological and anxiety disorders, such as schizophrenia, Alzheimer’s disease, and other various types of dementia.