Occipital Lobe: Function Location And Structure
The Occipital Lobe helps with visual processing and mapping. It is located under the parietal lobe and above the temporal lobe near the back of the brain.
- Occipital Lobe
The occipital lobe is the seat of most of the brains visual cortex, allowing you not only to see and process stimuli from the external world, but also to assign meaning to and remember visual perceptions. Located just under the parietal lobe and above the temporal lobe, the occipital lobe is the brains smallest lobe, but its functions are indispensable.
Building Our Visual World Step By Step
Our visual cortex is not uniform, and can be divided into a number of distinct subregions. These subregions are arranged hierarchically, with simple visual features represented in ‘lower’ areas and more complex features represented in ‘higher’ areas.
At the bottom of the hierarchy is the primary visual cortex, or V1. This is the part of visual cortex that receives input the thalamus. Neurons in V1 are sensitive to very basic visual signals, like the orientation of a bar or the direction in which a stimulus is moving. In humans and cats , neurons sensitive to the same orientation are located in columns that span the entire thickness of the cortex.
That is, all neurons within a column would respond to a horizontal bar. In a neighbouring column, all neurons would respond to oblique but not horizontal or vertical bars . As well as this selectivity for orientation, neurons throughout most of V1 respond only to input from one of our two eyes. These neurons are also arranged in columns, although they are distinct from the orientation columns. This orderly arrangement of visual properties in the primary visual cortex was discovered by David Hubel and Torsten Wiesel in the 1960s, for which they were later awarded the Nobel Prize.
Orientation columns in primary visual cortex, as viewed from above. All neurons within a column respond preferentially to bars of a specific orientation, denoted here by colour.Crair et als/Wikimedia
Brain Injury And Speech
What happens if one or more of these parts is injured, damaged, or abnormal?
If you have a problem speaking or understanding speech, its a condition called aphasia. If you have trouble putting together the correct muscle movements necessary to produce speech, its a condition called .
Symptoms of aphasia or apraxia depend on where the damage occurs in the brain and the severity of the damage. These symptoms include:
Recommended Reading: Midbrain Hemorrhage
Becoming Mindful Of The Brain And Its Functions
The human brain is the epicenter of the central nervous system, which controls the bodys most vital tasks. Everything from movement of limbs and facial features to regulating bodily functions like breathing is sent as a message from some part of the brain.
Comprised of billions of nerve cells that communicate with the body through the spinal cord, the brain is a complicated organ separated into several sections and subsections. Below is a breakdown of the parts of the brain, and how they contribute to the bodys functions and abilities.
Also called the cortex, the cerebrum makes up the largest part of the brain. It is associated with higher functions, such as cognitive thoughts and actions. There are four sections of the cerebrum , each of which contributes to the body differently. The four lobes and their functions are as follows:
The cerebellum resembles a smaller version of the cortex, because of its densely wrinkled appearance and its halved parts. It is responsible for several physical tasks, like movement, balance, posture and coordination. Although smaller in size, the cerebellum contains more neurons than the entire brain. It is critical for accomplishing day-to-day tasks as simple as walking or sitting down.
The Limbic System
The Brain Stem
There are three parts of the brain stem: the midbrain, the pons and the medulla. Below is an explanation of what each part does in relation to the brain system:
How The Brain Works
The brain is our motherboard, storage, operating system, and more. The nuances of its functions canât be summarized in a black-and-white dichotomy, which is how the left-and-right-brain idea came around.
The brain is divided into symmetrical left and right hemispheres. Each hemisphere is in charge of the opposite side of the body, so your right brain controls your left hand. The right hemisphere also takes in sensory input from your left side and vice versa.
The brain is segmented into regions called lobes. Your lobes isolate your brainâs functions to specific areas.
- The frontal lobe controls your body movement, personality, problem-solving, concentration, planning, emotional reactions, sense of smell, the meaning of words, and general speech.
- Your parietal lobe controls your sense of touch and pressure, sense of taste, and bodily awareness.
- The temporal lobe governs your sense of hearing, ability to recognize others, emotions, and long-term memory.
- The occipital lobe controls the important sense of sight.
- The cerebellum governs fine motor control, balance, and coordination.
- The limbic lobe controls emotions.
Read Also: Diffuse Slowing On Eeg
What Are Some Important Structures In The Occipital Lobe
Like all other lobes of the brain, the occipital lobe contains a number of structures and neuronal tracts that work together to enable vision. Those include:
- Brodmann area 17: Known as V1, this region is located in the occipital lobes calcarine sulcus, and serves as the brains primary visual cortex. It aids the brain to determine location, spatial information, and color data.
- The ventral stream: Known sometimes as V2, this is a secondary visual cortex that helps the brain assign meaning to what it is seeing. Without V2, you would still be able to see, but would have no conscious awareness of or understanding of the sights your eyes took in.
- The dorsomedial stream: Neuroscientists dont yet have a strong understanding of this brain region, which connects to both V1 and V2, as well as other brain regions.
- The lateral geniculate bodies: These structures take in optic information from retinal sensors in each eye, sending raw information to each visual cortex.
- Lingula: this area receives information from the contralateral inferior retina to gather information about the field of vision.
Brain imaging studies have revealed that neurons on the back of the gray matter of the occipital lobe create an ongoing visual map of data taken in by the retinas.
Understanding Vision And The Brain
Diseases which affect the visual pathway or the nerves to the eye muscles are often serious. This article summarises the anatomy and function of the 2nd, 3rd, 4th and 6th cranial nerves and the signs and symptoms which are important in making a correct diagnosis.
Double vision is a distressing symptom that warrants investigation. TANZANIA
Neuro-ophthalmology includes the specialties of neurology and ophthalmology. Skills of both specialties are needed to assess patients. A detailed history and clinical examination are needed in order to make a differential diagnosis and create a management plan.
There are two broad groups of neurological conditions that can affect someone’s vision:
Those which affect the visual pathways in the brain and
Those which affect eye movements.
If the condition affects the visual pathways, there can be loss of visual acuity, loss of visual field, or difficulties in understanding the visual world, depending on where the lesion is in the visual pathway. If the condition affects the 3rd, 4th or 6th cranial nerves, the main symptom is double vision due to restricted eye movements.
The visual pathways comprise the optic nerve, optic chiasm, optic tract, optic radiation and the visual cortex in the occipital lobes.
Also Check: Fluoride Bad For Brain
What Part Of The Brain Controls Peripheral Vision
Lets start with what peripheral vision is Its that part of your vision thats off to the edge of your central gaze. It could be to the left, right, up, or down relative to your central vision.
Our ability to see peripheral vision lies in the fovea, which is at the center of the macula inside the eye. Within the central fovea are rods and cones, with rods making up most of the perifoveal . Rods are more tuned to movement, shapes, and forms rather than fine detail.
This means that when you see something off to the side of your field of vision, you dont see it as well as if it were right in front of you. It correlates with the composition of the foveathe center of the fovea contains rods and cones, which means your central vision is more detailed. On the other hand, the peripheral fovea is primarily rods, so your peripheral vision is limited by the function of rods which do not convey sharp detail.
The rods impulses in the perifovea travel along the optic nerve to the anterior visual cortex in the occipital lobe for processing.
What Are The Regions Of The Brain And What Do They Do
The brain has many different parts. The brain also has specific areas that do certain types of work. These areas are called lobes. One lobe works with your eyes when watching a movie. There is a lobe that is controlling your legs and arms when running and kicking a soccer ball. There are two lobes that are involved with reading and writing. Your memories of a favorite event are kept by the same lobe that helps you on a math test. The brain is controlling all of these things and a lot more. Use the map below to take a tour of the regions in the brain and learn what they control in your body.
Read Also: Jahi Mcmath Necrosis
The Cerebrum And Cerebral Cortex
The cerebrum is the largest portion of the brain. It is covered in a thick layer of gray tissue called the cerebral cortex. Interior to the gray matter of the cerebral cortex is the white matter portion of the cerebrum. The white color comes from the layer of insulation called myelin that is on the neurons in this part of the brain.
The cerebrum is divided into two hemispheres that are joined by a band of nerves which allow communication between the two halves. The left hemisphere controls the right side of the body and the right hemisphere controls the left side of the body.
Brain Structure And Function
The brain has two halves or hemispheres: right and left. The right hemisphere controls the left side of the body, and the left hemisphere controls the right side. In most people, the left hemisphere regulates language and speech, and the right hemisphere controls nonverbal, spatial skills. If the right side of the brain is damaged, movement of the left arm and leg, vision on the left, and/or hearing in the left ear may be affected. Injury to the left side of the brain affects speech and movement on the right side of the body. Each half of the brain is divided into main functional sections, called lobes. There are four lobes in each half of the brain: the Frontal Lobe, Temporal Lobe, Parietal Lobe, and Occipital Lobe. Other important sections of the brain are the Cerebellum and the Brain Stem. Although not usually divided into lobes, the cerebellum and brain stem both have different parts. Each of the brain hemispheres and lobes, cerebellum, and brain stem has specific functions, and they all work together:
This image is from:
Frontal Lobe: most anterior, right under the forehead the frontal lobe controls intellectual activities, such as the ability to organize, as well as personality, behavior, and emotional control.
Parietal Lobe: near the back and top of the head above the ears the parietal lobe controls the ability to read, write, and understand spatial relationships.
Don’t Miss: What Does Crystal Meth Do To Your Brain
A Sorting Station: The Thalamus Mediates Sensory Data And Relays Signals To The Conscious Brain
The diencephalon is a region of the forebrain, connected to both the midbrain and the cerebrum. The thalamus forms most of the diencephalon. It consists of two symmetrical egg-shaped masses, with neurons that radiate out through the cerebral cortex. Sensory data floods into the thalamus from the brain stem, along with emotional, visceral, and other information from different areas of the brain. The thalamus relays these messages to the appropriate areas of the cerebral cortex. It determines which signals require conscious awareness, and which should be available for learning and memory.
Which Part Of The Brain Deals With Thinking
With more than 86 billion functional neurons, the brain is the most complex organ in the human body that deals with thinking. It controls everything that your body does and thinks.
It develops the main functions of the five senses: sight, sound, touch, taste, and hearing. And also helps primary functions such as breathing, talking, storing memories and thinking.
In other words, the brain is the boss of your body.
Many people wonder, which part of the brain deals with thinking?
We need to understand how our minds work so we can work our minds better.
Lets find out the answer to this question!
Recommended Reading: What Is Bleeding On The Brain Called
What Are The 3 Largest Parts Of The Brain
The brain has three main parts: the cerebrum, cerebellum and brainstem.
- Cerebrum: is the largest part of the brain and is composed of right and left hemispheres.
- Cerebellum: is located under the cerebrum.
- Brainstem: acts as a relay center connecting the cerebrum and cerebellum to the spinal cord.
What Part Of The Brain Controls Speech
The part of the brain which is responsible for speech is called the Brocas area. It is located in the cerebrum on the left side of the brain. Youll find it in the frontal lobe. Damage in Brocas area is characterized by slurred and unclear words. This condition is called Brocas aphasia or non-fluent aphasia.
Sufferers are able to understand what is being said, they know what they want to say, but the order from the brain to the speech organs cannot be executed.Speaking is a complex process, as it involves both speech comprehension and speech production. Healthy brains do both effortlessly.
Damage to any area involved in speech can cause various conditions such as dyslexia , anomia , and agraphia .
Read Also: Evander Holyfield Brain Damage
Unexpected Link Between Posture And Your Eyes
As an infant, you learned about the relationship between your body parts through trial and errorreaching out and making contact. As a child, maybe you recited your facial features as fast as you could or sang a ditty to remember that your neck bone connects to your head bone.
Anatomical links affect more than the way you learnthey can change and, even, dictate your health. In this blog, youll discover the link between your posture, or how you stand, and your eyes.
Understanding the Link
To use the link between the position of your spine and your optic health to your advantage, you first must understand how the connection works.
Eyes to Brain
Your eyes represent a complex part of your central nervous system, connected directly to the brain. To see the way you do, your eyes accept light beams. These beams hit the photoreceptors, known as rods and cones, located in your retina at the back of your eyeball.
The signals the retina receives translate into electrical impulses, which travel on the optic nerve into the brains visual cortex.
Brain to Spine
When impulses reach the visual cortex, your brain interprets them and uses them to determine how the body should respond. The brain sends messages down the spinal cord to tell the rest of your body how to react to what the eyes see.
Eyes to Spine
Results of This Connection
Blurred vision or difficulty focusing the eyes Decreased circulation which causes numbness and muscle strength issues Eye strain or fatigue
What Is A Stroke
A stroke occurs when the supply of blood in the brain becomes compromised. This can happen by either a blood clot obstructing an artery and stopping blood flow to an area of the brain or an artery in the brain bursting and leading to bleeding inside the brain .
During a stroke, the affected areas of the brain do not receive enough oxygen-rich blood. As a result, brain tissue begins to die. Depending on the area of the brain affected by stroke, this damage will cause changes in certain sensory, motor, or cognitive functions.
Although its impossible to revive dead brain cells, recoveryis possible through neuroplasticity.This process allows healthy parts of the brain to take over the functionsdamaged by stroke.
The goal of stroke rehabilitation is to restore or compensate for the secondary effects sustained to your highest potential. These effects vary from person to person based on the size and location of the stroke.
Next, we will discuss the different areas of the brainaffected by stroke so that you can better understand what to expect.
Also Check: Left Temporal Slowing On Eeg
What Are The Different Parts Of The Brain
The brain can be divided into the cerebrum, brainstem, and cerebellum:
Cerebrum. The cerebrum is composed of the right and left hemispheres. Functions of the cerebrum include: initiation of movement, coordination of movement, temperature, touch, vision, hearing, speech and language, judgment, reasoning, problem solving, emotions, and learning.
Brainstem. The brainstem includes the midbrain, the pons, and the medulla. Functions of this area include: movement of the eyes and mouth, relaying sensory messages , hunger, respirations, consciousness, cardiac function, body temperature, involuntary muscle movements, sneezing, coughing, vomiting, and swallowing.
Cerebellum. The cerebellum is located at the back of the head. Its function is to coordinate voluntary muscle movements and to maintain posture, balance, and equilibrium.
More specifically, other parts of the brain include the following: