The brain is the most important organ that controls the human body. Thanks to its functioning, people are able to see, hear, walk, experience emotions, communicate with each other, feel, analyze, think and love. The latter properties are unique to humans. Before answering the question of what the left hemisphere of the brain is responsible for, you need to remember 9th grade anatomy: what the brain consists of.
Brain structure
The mass of the organ in an adult is approximately 1400 g. It is located in the cavity of the cranium, covered on top with membranes (soft, hard, arachnoid). We can distinguish 3 most significant parts: hemispheres, cerebellum, trunk. The hemispheres of the brain regulate higher nervous activity; they contain the departments responsible for vision, hearing, speech, and writing. The cerebellum provides balance; the brainstem contains the centers for controlling breathing and heartbeat.
Interesting! The brain in men completes its growth by the age of 25, and in women by 15!
Between the cerebral hemispheres there is a longitudinal fissure, in the depth of which the corpus callosum is located. The latter connects both hemispheres and allows them to coordinate each other’s work. From anatomy lessons, many remember that each hemisphere controls the opposite side of the body. It follows from this that the left hemisphere is responsible for the right half of the body.
The brain has 4 lobes (we will talk about them below). The lobes are separated by three main grooves: Sylvian, Rolandov and parieto-occipital. In addition to the grooves, the brain has many convolutions.
It is useful to know what abstract thinking is: forms, possibilities.
Why does a person need cognitive functions: connections with parts of the brain, causes of impairment.
The brain matter itself is divided into gray (cortex) and white. The gray is made up of neurons and lines the top of the brain. The thickness of the cortex is approximately 3 mm, and the number of neurons is about 18 billion. White matter is the pathways (neurocyte fibers) that occupy the rest of the brain. It is the cortex that controls a person’s entire life from sleep to the manifestation of emotions.
Spinal cord. Brain - 8th Grade Biology Workbook. Mash, Dragomilov.
JOB 157
1. Read §49. Look at the drawing. Label the parts of the spinal cord with numbers.
2. Answer the questions. Is the anterior or posterior sulcus of the brain shown in the foreground of the picture? Front. On which side of the brain (right or left) are the numbers assigned? Left. From which side (back or front) do nerve impulses from organs enter the brain (feedback), and commands are sent to organs (direct connections)? Information comes from the back, commands are sent from the front.
JOB 158
Consider a drawing depicting a reflex arc when a hand is burned. Answer the questions. 1. Is there hair on the palm or back of the hand? Was the victim burned on the back or palm side? On the back. The victim was burned on the palmar side. 2. Which parts of the reflex arc are marked with numbers in the figure?
Check your answers in §49 of the textbook.
JOB 159
Read §50 and complete the assignments. 1. Look at the picture showing the right half of the brain. Indicate the colors for the medulla oblongata, pons, midbrain, diencephalon, cerebellum, and cerebral hemispheres. Write the names of the parts of the brain.
2. Answer the questions. What is the function of the corpus callosum? Connects the right and left hemispheres. Which side of the body does the right side of the brain control and from which side of the body does it receive information? Controls and receives information from the left hemisphere.
WORK 160
Explain the following concepts (see §50) . Gray matter of the brain The gray colored nervous tissue that makes up the cerebral cortex and the central part of the spinal cord, consisting of the cell bodies of neurons. White matter of the brain This is the nervous tissue, consisting of the nuclei of neurons covered with a myelin sheath, contained in the brain and spinal cord. Cerebral nuclei are “islands” within the brain of gray matter. Vagus nerve One of 12 pairs of vagus nerves that regulates the functioning of internal organs. Sympathetic nerve A nerve of the autonomic nervous system that gives branches to the same organs as the vagus nerve. Most often their actions are opposite. Somatic Nervous System The part of the nervous system that is controlled by the will innervates the bone muscles.
JOB 161
Fill out the table (see §50).
JOB 162
1. What are the names of the lobes of the cerebral hemispheres? (see §50). 2. Indicate which colors are highlighted in the picture: visual zone; auditory zone; motor area; zone of skin-muscular sensitivity. Auditory – brown, motor – orange, visual – green, musculocutaneous sensitivity – red.
JOB 163
The figure shows speech centers. 1. In the auditory zone of the temporal lobe there is Wernicke's center (1), associated with speech perception. In the motor area of the frontal lobe there is Broca's center (2), associated with the ability to speak. Name the functions of centers 1 and 2. 1-speech perception. 2-ability to speak
2. Nerve pathways located inside the brain tissue connect centers 1 and 2. Why does deafness that occurs in children ultimately lead to speech disorders and even muteness? Children learn to speak by hearing the speech of others. If a child is unable to perceive speech, he will not be able to produce it.
Functions of the left hemisphere of the brain
Large hemispheres are not separated from other components of the nervous system; they work together with subcortical structures. In addition, if one hemisphere is damaged, the other can partially take over the functions of the first, which indicates the joint support of movements, sensitivity, higher nervous activity and sensory organs.
The cortex is divided into zones responsible for certain functions (vision, hearing, etc.), but they do not function separately. To say something, a person must first think, analyze, calculate. During a conversation, people show emotions (sadness, joy, anxiety, laughter), gesture, that is, use their hands and facial muscles. All this is ensured by the coordinated work of several zones of the cortex, subcortical nuclei, cranial and spinal nerves. So, what are the different lobes of the brain responsible for?
Interesting! Less than half of the human brain has been studied!
Frontal lobe of the left hemisphere of the brain
Responsible for movement, the ability to speak, individuality, thinking. The frontal lobe is the part of the brain responsible for emotions, behavior, and thinking.
Motor cortex
Responsible for the activity of the striated muscles of the right half of the body, coordination of precise movements, and orientation on the ground. This department receives impulses from internal organs. When it is damaged, ataxia, paresis of the limbs, and disturbances in the functioning of the heart, blood vessels, and breathing occur. The picture below shows the topical affiliation of organs and body parts to the precentral gyrus.
Speech motor area
Ensures the work of facial muscles to pronounce complex words and phrases. In other words, it is responsible for the formation of speech. In all right-handed people, the speech motor area in the left hemisphere occupies a larger area than in the right.
When this zone is destroyed, the person loses the ability to speak, but can scream or sing without words. Reading to oneself and the formulation of thoughts are also lost, but the ability to understand speech does not suffer.
What is the right hemisphere responsible for?
The right hemisphere is responsible for processing signals, as well as identifying objects and merging them with essence. The development of this side of the human brain also determines the ability for art and creative activities, for example, drawing, modeling. Thanks to it, we can perceive music, works of art, dance numbers, and also derive pleasure or displeasure from them. People whose right side is well developed can also create their own masterpieces.
Functions of the right hemisphere:
- Responsible for spatial orientation. Due to its work, a person is able to determine the location of objects relative to himself and the distance to them. As a result, a person remembers the route and minimizes the risk of getting lost even in unfamiliar places.
- Allows you to perceive and respond to allegory. A person is able to perceive proverbs, sayings, analyze them, draw conclusions and respond to them. This also includes a sense of humor and the ability to laugh at an anecdote or joke rather than take everything literally.
- Responsible for imagination. We can create stories, mental images, and dream and fantasize. An example of this is dreams.
- Allows you to react emotionally to events happening around, words and addresses of other people. We can guess that we are being deceived, about the negative actions of other people and protect ourselves from possible danger.
- Helps to recognize people by facial features and distinguish strangers from acquaintances.
It also has the ability to process a large amount of information simultaneously and perceive it as one whole. As a result, a person is able to easily solve the tasks assigned to him.
Temporal lobe
The auditory zone is responsible for hearing and vestibular sensitivity. When the zone on the left is destroyed, deafness occurs on the right side, and the ability to hear in the left ear sharply decreases, movements become inaccurate, and staggering occurs when walking (see Ataxia). Nearby is the auditory speech center, thanks to which people understand the addressed speech and hear their own.
The area of taste and smell works together with the stomach, intestines, kidneys, bladder, and reproductive system.
Occipital lobe – visual area
The visual fibers at the base of the brain also cross, as do the auditory fibers. Thus, impulses from both retinas of the eyes go to the visual part of the left hemisphere. Therefore, if this zone is damaged, complete blindness does not occur, but only half of the retina on the left is affected.
The occipital part of the brain is also responsible for the visual speech center, the ability to recognize written letters and words, so people can read text. The picture shows the parts of the brain responsible for behavior, memory, hearing, and touch.
The difference between the left hemisphere and the right
As has already become clear, both hemispheres have speech, visual, auditory and other zones. So what is the difference between them? Is it only in control over the opposite halves of the body? Of course not!
Features of the left hemisphere:
- Logic, analysis, thinking.
- Numbers, mathematics, calculation.
- Step-by-step solutions to complex problems.
- The ability to understand literally.
- Clear facts, arguments, without unnecessary information.
- Teaching foreign languages, the ability to control speech.
All about the limbic system: structure and functions, disorders and their consequences.
It is useful to know what the sella turcica is in the brain: its role in the human body, signs of dysfunction.
Everything about the pineal gland: from anatomy to diseases.
What is the right hemisphere of the brain responsible for?
- Intuition, imagination, emotions.
- Perception, musicality, artistry.
- Fantasy, bright colors, the ability to dream.
- Creating an image from a description, a passion for mysticism and riddles.
You yourself know how to develop your right hemisphere!
The three basic exercises are just a simple example. If you want, you can easily find a lot of things that can develop both one and the other hemisphere of the brain. This is facilitated by communication with people and the desire to sympathize and experience them, listening to classical music (especially live performance). Pay more attention to what is happening around you and be aware of what is happening without resorting to constant analysis. It really won’t be a bad idea to do this, because the acquired skills will be useful in any business and any industry.
