Sunday, May 8, 2022

What Part Of The Brain Controls Eyesight

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Parts Of The Brain: Structures Anatomy And Functions

Mind Control – Reptilian Brain. The Eyes Are Directly Connected To The Reptilian Brain.

The human brain is one of the largest and most complex organs in the body. It controls your emotions, thoughts, speech, memory, creativity, breathes, movement, and stores information from the outside world. This article discusses the different parts of the brain and the function of each structure.

The brain is a 3-pound organ that contains more than 100 billion neurons and many specialized areas. There are 3 main parts of the brain include the cerebrum, cerebellum, and brain stem. The Cerebrum can also be divided into 4 lobes: frontal lobes, parietal lobes, temporal lobes, and occipital lobes. The brain stem consists of three major parts: Midbrain, Pons, and Medulla oblongata. Although each structure has a distinct function, they work together to control all functions of the body.

What Its Like To Hallucinate

Visual hallucinations, specifically simple hallucinations are more prevalent among the general population. These hallucinations include lights, colors, lines, or simple geometric shape. They can reflect abnormal activity anywhere along the visual pathways in the eye or the brain, Kelley said.

When people have these simple geometrical hallucinations, the primary visual cortex is activate. This is the part of the brain that perceives edges and patterns. Images cannot be formed with the primary visual cortex. They generate when a higher part of the visual cortex, according to Sacks, is involved in the temporal lobe, specifically the fusiform gyrus.

To experience a drug-free hallucination, click on the video below to see the world melting before your eyes with objects and people distorted in real-time, the DailyMail reported. This is known as motion aftereffects, which makes you see movement in objects that are stationary. You can recreate the effect on-the-go with the Strobe Illusion iPhone app for 99 cents.

The mind is a terrible thing to waste, so use it wisely.

The Seat Of Consciousness: High Intellectual Functions Occur In The Cerebrum

The cerebrum is the largest brain structure and part of the forebrain . Its prominent outer portion, the cerebral cortex, not only processes sensory and motor information but enables consciousness, our ability to consider ourselves and the outside world. It is what most people think of when they hear the term grey matter. The cortex tissue consists mainly of neuron cell bodies, and its folds and fissures give the cerebrum its trademark rumpled surface. The cerebral cortex has a left and a right hemisphere. Each hemisphere can be divided into four lobes: the frontal lobe, temporal lobe, occipital lobe, and parietal lobe. The lobes are functional segments. They specialize in various areas of thought and memory, of planning and decision making, and of speech and sense perception.

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Areas Of The Brain Affected By Stroke And Symptoms

Below, youll learn about the different parts of the brain that can be impacted by stroke. You will find a short summary of the  effects of each type of stroke, and you can click the link in each section to learn more.

The effects of a stroke will vary from person to person, so its best to reference a full list of the secondary effects of stroke to get an even better idea of what to expect after stroke.

Here are the major areas of the brain that can be affectedby stroke:

Causes Of Neurological Vision Loss

TL
  • stroke or brain attack, where part of the brain is damaged by a haemorrhage or blockage in a blood vessel of the brain
  • traumatic brain injury for example, after a car accident or fall
  • infection, such as meningitis or cytomegalovirus
  • lack of oxygen, such as near-drowning or a heart attack, which can interrupt the flow of blood to the brain
  • disease, such as a brain tumour or multiple sclerosis.

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How Your Eyes Work With Your Brain

For instance, when you look at your phone, a particular part of your brain called the pons controls your eye muscles to direct your gaze.

The image of your phone then gets sent through your pupils. It hits the photoreceptor cells in the macula at the back of the eye, including rods and cones .

Rods and cones fire a nerve impulse through the optic nerve, which carries the impulse to a structure at the back of your brain called the occipital lobe.

The occipital lobe processes the image of your phone. However, this is not the end of the sight process.

Next, the visual data is sent to the parietal lobe, which is responsible for giving awareness of the physical distance between you and the phone and your depth perception.

The visual data is also sent to the temporal lobe, which is associated with memory. It recognizes that what youre looking at is a phone and not a shoe or anything else but a phone.

The temporal lobe is responsible for giving meaning to what we seeits what helps you use your phone for its intended purpose, rather than eating it or using it as a shoehorn.

Also, there is evidence that the frontal lobe, which is the reasoning/thinking part of our brain, is involved in the process of vision. The frontal lobe is responsible for maintaining your focus. In this case, it holds your attention on your phone and only your phone and not anything else around it.

The Brain Stem Relays Signals Between The Brain And Spinal Cord And Manages Basic Involuntary Functions

The brain stem connects the spinal cord to the higher-thinking centers of the brain. It consists of three structures: the medulla oblongata, the pons, and the midbrain. The medulla oblongata is continuous with the spinal cord and connects to the pons above. Both the medulla and the pons are considered part of the hindbrain. The midbrain, or mesencephalon, connects the pons to the diencephalon and forebrain. Besides relaying sensory and motor signals, the structures of the brain stem direct involuntary functions. The pons helps control breathing rhythms. The medulla handles respiration, digestion, and circulation, and reflexes such as swallowing, coughing, and sneezing. The midbrain contributes to motor control, vision, and hearing, as well as vision- and hearing-related reflexes.

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The Mystery Of Hearing

A brief description of the workings of the ear can make them soundsimple and straightforward. But in fact, the more we learn of hearing,the deeper a mystery it becomes. For example, it was recentlydemonstrated that the ear emitssounds. When someone hears a ringing in the ears that same ringing can be measured and recorded in the earcanal. It is even audible to others. If you hold your ear to someoneelses, and if the room is very quiet, you can hear the reportedringing from the other persons ear. This mystery is called cochlearamplification, and no one knows what causes it or how it works.

While the auditory pathways are still not fully understood, we knowenough to comprehend that the gift of hearing is instilled with magicand wonder.

Ted Uzzle is director of instructional development at NSCA andeditor emeritus of S&VC.

How Do Eyes Work

Biology – Important parts of brain and their functions – Control and coordination – Part 3 English

The images we see are made up of light reflected from the objects we look at. This light enters the eye through the cornea, which acts like a window at the front of the eye. The amount of light entering the eye is controlled by the pupil, which is surrounded by the iris the coloured part of the eye.

Because the front part of the eye is curved, it bends the light, creating an upside down image on the retina. The brain eventually turns the image the right way up.

The retina is a complex part of the eye, and its job is to turn light into signals about images that the brain can understand. Only the very back of it is light sensitive: this part of the retina is roughly the area of a 10p coin, and is packed with photosensitive cells called rods and cones.

Cones are the cells responsible for daylight vision. There are three kinds, each responding to a different wavelength of light: red, green and blue. The cones enable us to see images in colour and detail. Rods are responsible for night vision. They are sensitive to light but not to colour. In darkness, the cones do not function at all.

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Which Part Of The Brain Deals With Sight

Interestingly enough, vision is controlled by the part of the brain which is furthest away from the eyes themselves the occipital lobe. It is located in the back of your head above the brain stem, the part of our brain that controls breathing.

The occipital lobe also has two hemispheres. The left hemisphere processes information from the right eye and vice versa.

The primary visual cortex gets raw information from the eyes and sends them to the secondary visual cortex for further processing. The secondary visual cortex is made out of the ventral stream and dorsal stream. Visual stimuli are processed in the temporal lobe as well.

Its important to keep the brain healthy and to challenge it with new tasks on a daily basis. That way, we can keep our brains strong and functioning well.

Thanks to Brocas area we can share our thoughts and ideas with people around us. What thoughts would you like to share with us below?

Control Your Attitude & Brain One Nutrient At A Time

We are a nation in pain with over 264 million people of all ages suffering from depression. For many, a conversation on poor nutrition conjures photos of someone standing on a bathroom scale and staring helplessly at the numbers as they climb higher and higher. But how many people realize the connection between poor nutrition and the brain?

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The Color System Of The Eye

Cone cells contain a pigment through which light must pass beforereaching the receptor. There are three pigments: One passes violet,with a wavelength of 430 nm; one passes blue-green, with a wavelengthof 530 nm; and the last pigment passes yellowish-green, with awavelength of 560 nm. In fact, these optical filters have filterskirts, meaning they pass light of other wavelengths, but with reducedsensitivity. Any monochromatic light actuallyactivates cone cells of multiple pigments, but at differentsensitivities. This also explains why we can see light with wavelengthsshorter than 430 nm, and longer than 560 nm.

No conecells, however, can truly perceive red. The closest we really get isyellowish-green. What we call red is really an opticalillusion, supplied by the brain by means of extrapolation. Oursensitivity to red is dramatically reduced compared to other colors,and our visual acuity in the red end of the spectrum is extremely bad.Everyone knows not to focus a projector using a redtest pattern. This is why the red gun in color-video equipment needsthe least resolution to be satisfactory .

Folk wisdom has many sayings about believing what you hear andbelieving what you see. The visual sense is just as prone to illusionas the auditory pathway, and equally filled with mystery andmisunderstanding. Maybe belief should rest not on the particularsensory pathway but rather on our understanding of the ways and meansthrough which we view the world.

The Hypothalamus Manages Sensory Impulses Controls Emotions And Regulates Internal Functions

What part of the brain controls vision?

The hypothalamus is part of the diencephalon, a region of the forebrain that connects to the midbrain and the cerebrum. The hypothalamus helps to process sensory impulses of smell, taste, and vision. It manages emotions such as pain and pleasure, aggression and amusement. The hypothalamus is also our visceral control center, regulating the endocrine system and internal functions that sustain the body day to day. It translates nervous system signals into activating or inhibiting hormones that it sends to the pituitary gland. These hormones can activate or inhibit the release of pituitary hormones that target specific glands and tissues in the body. Meanwhile, the hypothalamus manages the autonomic nervous system, devoted to involuntary internal functions. It signals sleep cycles and other circadian rhythms, regulates food consumption, and monitors and adjusts body chemistry and temperature.

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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 lobe’s calcarine sulcus, and serves as the brain’s 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 don’t 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.

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, you’ll 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

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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 brain’s 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 brain’s smallest lobe, but its functions are indispensable.

What Part Of The Brain Controls Color Vision

What part of the brain controls speech?

There is a particular part of the occipital lobe that handles color vision. Its called the visual cortex. There are two visual cortexes, a left and a right one on each occipital lobe.

For example, when you see an apple, the apples light gets picked up by the photoreceptors inside the eye . Rods and cones receive the wavelengths of light given off by the appleespecially the cones since theyre the eyes color receptor.

The cones send the impulse through the optic nerve to the visual cortex in the occipital lobe. The brain processes this input based on how many cones were activated and the signals strength. Thats how you see the color of the apple is red.

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What Part Of The Brain Controls Depth Perception

Specifically the part of the brain that does depth perception based on binocular vision. I have searched all over the web and have turned up nothing. Is it the same part of the brain that processes all images from the retina?

This Scientific American article states that there is a process involved:

Visual-image processing from the eye to the brain happens in stages. Rudimentary features such as the orientation of edges, direction of motion, color, and so on are extracted early on in areas called V1 and V2 before reaching the next stages in the visual-processing hierarchy for a progressively more refined analysis. This stage-by-stage description is a caricature; many pathways go back from stage to stageallowing the brain to play a kind of 20-questions game to arrive at a solution after successive iterations.

This process is discussed further in this article with what is known as the Laminart model.

Pressure On The Optic Nerve

As the tumour grows, or there is a build-up of cerebrospinal fluid in the brain, it can squeeze normal healthy brain tissue including the main cranial nerves within the brain. The resulting pressure can alter how well the nerve works, and if this happens to the optic nerve, your vision can be affected.

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How Do We See

The wall of an eyeball has three layers, rather like the layers of an onion:

  • The sclera is the protective layer. This tough, fibrous tissue surrounds the eyeball and attaches to the cornea, which is the clear front surface of the eye. What we see as the white of the eye is the sclera. Over the sclera lies the conjunctiva, a clear skin layer that protects the eye from becoming dry.
  • The choroid is the middle layer that contains blood vessels that deliver oxygen and nutrients to the inside parts of the eye.
  • The retina , the innermost of the three layers, lines the inside of the eyeball. The retina is a soft, light-sensitive layer of nervous system tissue. The optic nerve carries signals from the retina to the brain, which interprets them as visual images.
  • The space in the center of the eyeball is filled with a clear jelly-like material called the vitreous humor. This material allows light to pass through to the retina. It also helps the eye keep its round shape.

    Vision is the process by which images captured by the eye are interpreted by the brain, and the visible part of the eye is where the process of sight begins. On the front surface of the eye is the see-through, circle-shaped cornea. You can’t see a person’s cornea the way you can see the colored part of the eye behind it the cornea is like a clear window that focuses light into the eye.

    What Happens If The Occipital Lobe Is Damaged

    Brain Anatomy

    The most obvious effect of damage to the occipital lobe is blindness, but occipital lobe damage can have other surprising effects:

    • Epilepsy: Some seizures occur in the occipital lobe, and occipital lobe damage increases vulnerability to seizures.
    • Difficulties with movement: Even if you are still able to move, changes in depth perception and vision can lead to inappropriate movements and difficulty navigating the visual field.
    • Difficulties perceiving colors, shape, dimension, and size.
    • Difficulty recognizing familiar objects or faces.
    • Hallucinations

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    A Range Of Neurological Vision Loss

    • visual field defects such as homonymous hemianopia, when one half of the visual field in each eye is missing
    • double vision where a single object is seen as two and cannot be merged together
    • fluctuating vision this means the impairment is variable, for example, the person may be able to see something one day, but not the next
    • visual acuity problems reduced clarity of vision
    • eye movement problems for example, jittery eye movements or the tendency of the eyes to flicker around when the person is trying to look steadily at something
    • strabismus the eyes are not aligned for example, it may turn inwards or outwards.

    Left Hemisphere Vs Right Hemisphere Stroke

    Along with different lobes and structures, the brain is alsodivided into two halves, called hemispheres.

    Aside from the different areas of the brain that can beaffected by stroke, its also helpful to look at difference between the twohemispheres.

    Generally speaking, the left hemisphere controls languageand logical reasoning; while the right hemisphere is believed to control creativityand object recognition. This is why language difficulties after stroke areoften associated with left hemispherestrokes.

    Furthermore, each hemisphere controls movement on the opposite side of the body. Usually, a left hemisphere stroke will cause motor impairments on the right side of the body; while a right hemisphere stroke will likely impair the left side of the body.

    When stroke impacts both hemispheres, its possible tosustain motor impairments on both sides of the body.

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    What Part Of The Brain Is Responsible For Vision

    As soon as the information passes from the optic nerve to the remainder of the brain, it is sent to the occipital lobe, where vision is processed. The occipital lobe is located in the back of the brain, above the cerebellum, and forms the center of the visual perception system, according to the Centre for Neuro Skills. Each hemisphere has its own occipital lobe; therefore, each occipital lobe processes the information sent to that particular hemisphere. The occipital lobe controls how an individual views sight, so damage to this brain section can result in visual field cuts, and problems identifying color or movement of a things.

    Visual Cortex

    The last part of the brain associated with vision is the visual cortex, where sensory and motor info is incorporated with vision. The Canadian Institutes of Health Research states that several visual pathways are included. For instance, the ventral visual path controls how an individual identifies items, while the dorsal visual path manages an individuals visual-motor action to things. To puts it simply, the visual cortex enables you to understand that youre taking a look at a plate, for example, and then permits you to choose it up.

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    The Coordinated Balance System

    Cortical Vision Impairment – When That Part Of The Brain Is Damaged, Visual Images Are Not Received

    The human balance system involves a complex set of sensorimotor-control systems. Its interlacing feedback mechanisms can be disrupted by damage to one or more components through injury, disease, or the aging process. Impaired balance can be accompanied by other symptoms such as dizziness, vertigo, vision problems, nausea, fatigue, and concentration difficulties.

    The complexity of the human balance system creates challenges in diagnosing and treating the underlying cause of imbalance. The crucial integration of information obtained through the vestibular, visual, and proprioceptive systems means that disorders affecting an individual system can markedly disrupt a persons normal sense of balance. Vestibular dysfunction as a cause of imbalance offers a particularly intricate challenge because of the vestibular systems interaction with cognitive functioning,2 and the degree of influence it has on the control of eye movements and posture.

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