optical nerve

anonymous asked:

(Resending in case my ask got eaten) I'm wanting to write a character who survives a gunshot to the head, but he develops a stutter because of it. Is this possible? What part of the brain would have to be hit for that to happen? Or is this more of a scriptshrink question?

Hey there nonny.

A stutter is likely to be the least of your character’s worries. Even if they survive a GSW to the head, they’re likely to have severe brain injuries because of it. What I’m saying is, a stutter is a consequence of this injury, but it should not be the only consequence. Y’feel?

These can include, but are in no way limited to:

  • Personality changes (quick to anger, limited attention span, different reactions to situations/stimuli)
  • Motor dysfunction
  • Vision changes due to brain damage or damage to the optic nerve (or even the eyeball itself)
  • Aphasia (having trouble finding words)
  • Inability to read, if Broca’s area was damaged.
  • Executive dysfunction (decision-making capacity is impaired)
  • Short attention spans
  • Memory loss (loss of long-term memories, difficulty forming new ones)
  • Having to re-learn skills – both advanced (typing, driving, playing pool, calculating trajectories), and basic (walking, tying shoes, ….)
  • Having to re-learn basic things (colors, etc.)
  • They may have seizures, and these may be occasional and well-managed with medication, or may be frequent and unmanageable, or somewhere in the middle.

I’m sure that  there are more features or complications that I’m missing. Your character will likely have spent significant time in rehab.

So yes… your character may stutter. That can be neurological or psychological, but it’s possible. They may also slur speech, or have some problems with moving parts of their face, or they may reach for words and never quite find the ones they want, or their attention may wander in the middle of their sentence.

A resource: brainline.org is a phenomenal resource about head injuries of all kinds.

If you want a really good reference for what a story about a post-GSW-to-head character looks like, watch a Harrison Ford movie called Regarding Henry. It’s a great story, although it does lean pretty heavily on Amnesia! as a driving portion of the plot.

xoxo, Aunt Scripty

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Tomine, Sala, Clowes

In chapter 2 of Adrian Tomine’s excellent Shortcomings, the main character – the mean-spirited, uptight, yet somehow likeable Ben Tanaka – hangs out in a Bay Area bookstore. On the shelf behind Ben are books by three Bay Area cartoonist friends: Tomine’s Scrapbook; Richard Sala’s Peculia; and Daniel Clowes’s Eightball #23 (The Death-Ray):

Chapter 2 of Shortcomings first appeared in Tomine’s comic-book series Optic Nerve #10 in 2005, while Eightball #23 came out in 2004, Peculia in 2002, and Scrapbook in 2004. (Tomine has since moved to New York, as some of Shortcoming’s main characters do; but the downtrodden Ben Tanaka does not.)

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GLAUCOMA

What is Glaucoma?

Glaucoma is when the intraocular pressure is elevated, compromising vision either partially or completely.

What causes Glaucoma to develop?

In a patient with healthy eyes the aqueous humor produced within the Ciliary body located behind the Iris flows through the Pupil and drains through a sieve structure found in the corner of the eye known as the Iridocorneal Cleft. The fluid is produced and then drained at a steady rate resulting a stable intraocular pressure (IOP) of 15-20mmHg.

In the unhealthy eye, there is inadequate outflow of aqueous humor through the Iridocorneal Cleft resulting in the build up of fluid within the eye. This causes the IOP to increase, the more this increases the more damage is done to the Optic nerve which blocks nerve impulses causes blindness.

Does it cause permanent blindness?

The longer the IOP is increased the more damage is done to the Optic nerve, once this is permanently damaged vision can not be restored. Therefore, early surgical intervention is strongly recommended. 

Is there only one type of Glaucoma?

No, there are two types of Glaucoma. These are:

Primary Glaucoma - This is thought to be the inherited type and is seen mainly in purebred dogs. It is caused by either:

  1. Open Angle Glaucoma - Where the point where the Iris meets the Corneal is open at the correct angle but the Iridocorneal Cleft becomes clogged over time resulting in a slow loss of peripheral vision until the whole eye is effected. This type of Glaucoma has little warning signs and is seen most commonly in Beagles and Norwegian Elkhounds.  
  2. Narrow Angle Glaucoma - This type of Glaucoma occurs suddenly when the Iris is pushed or pulled forward blocking the drainage angle. Commonly seen in Cocker Spaniels and is a medical emergency causing pain, redness of the eye, dilated pupils, nausea and vomiting.
  3. Gondiodysgenesis - This is a developmental abnormality of the actual drainage angle causing decrease fluid outflow when the eye becomes inflamed. It is commonly seen in Basset Hounds.

Secondary Glaucoma - This is often the result of pre-existing ocular conditions such as Uveitis, Lens dislocation, Intraocular tumours and trauma to eye interfering the natural flow of ocular fluid. 

The clinical signs of Glaucoma include:

  • Excessive tear production
  • Yellow/Green Ocular discharge
  • Reddened Eye
  • Behavioural changes due to pain and loss of vision
  • Enlarged Pupil that doesn’t respond to light
  • Enlarged Eye

How is Glaucoma diagnosed?

Diagnosis is made by evaluation of clinical signs and taking a detailed history from the client. In addition to this two diagnostic techniques are used, these are:

  1. Tonometry - The measurement of IOP with a Tonopen.
  2. Gonioscopy - Evaluation of the drainage angle, done by placing anaesthetic drops into the eye and then installing a dome shaped lens onto the corneal surface. The front of the eye can then be examined with a slit lamp.  

What treatment is available?

Glaucoma in animals is much more difficult to treat than when it is present in human eyes. Mannitol is the intravenous drug of choice used to decrease the IOP, while eye drops such as Pilocarpine are used to increase the outflow of Aqueous humor. Once the IOP is stable, surgical options become available. 

If vision is present:

Laser Cyclophotocoagulation - A laser is used to burn through the white outer layer of the eye and selectively destroy small areas of the ciliary body to reduce the production of eye fluid. Occasionally more than one surgery is needed to achieve a positive outcome from this treatment.     

Cyclocryothermy - A small probe is placed on the outside of the eye and small areas of ciliary body are frozen to decrease the amount of intraocular fluid being produced. 

Anterior Chamber Shunts - A small valve is implanted under the white of the eye through a small incision acting as a new drainage pathway for the fluid to leave the eye.

If vision isn’t present: 

Evisceration and Implantation of Intrascleral Silicon Prosthesis – A silicone implant is implanted within the eye. This procedure involves shelling out the eye leaving the fibrous sclera and cornea, the shape of the eye is maintained with a sterile silicone sphere and the eye is pain free for the patient. Complications include corneal ulceration.

Ciliary Ablation by Intravitreal Injection of Gentamycin – Gentamycin (a antibiotic) is injected into the eye in high concentrations, the ciliary body is killed resulting in the cessation or reduction of aqueous humor production. A GA is needed and complications can include: shrinking of the eye, return of glaucoma and chronic pain.

Enucleation – Removal of the eye.

lheonce  asked:

hi! first, i love your blog, and it really helped me with writing injuries. quick question, though, would it be possible to lose the ability to see from one eye due to significant head trauma?

Hey there! Thanks for writing in, and I’m super glad I can be of use!!

Yes, this is definitely possible. Blindness from both eyes requires much more damage, but one of three things could happen to cause single-eye blindness from trauma.

First, The eye itself, remember, is part of the head, and could be physically damaged.

Alternatively, direct trauma or swelling (from bleeding or from inflammation) could damage the optic nerve on the affected side.

It’s also possible to have interpretation issues (in the visual cortex) that could lead to loss of vision in one side of the visual field. To quote a frankly phenomenal brainline.org interview:

Visual field loss is a bit more complicated. Think of your visual field as a pie. Visual field loss is categorized by which part of the pie is affected.

  • If you have hemianopsia, half of your pie — or visual field, either vertically or horizontally — is gone; you cannot see it.
  • If you have quadranopsia, a quarter of your visual field is lost.
  • If you have homonymous hemianopsia, the same quarter or half is lost in both eyes.
  • If you have bitemporal hemianopsia, you are missing the outer half (or inner half) of both the right and left visual field.

Hemianopsia and quadranopsia are the most common types of visual field losses; but going back to the pie analogy, other types of field losses include loss around the edges of the pie or loss from the middle going outward. And, of course, there can be differing combinations depending upon the individual injury.

Visual field loss is caused by damage to the nerve fibers that carry the visual signal from the eyes to the visual cortex and/or connect operations between different parts of the brain.

So there you have it. That link has information about coping strategies for those affected by visual field loss and more – including a fascinating differentiation about spatial neglect (whether or not the person is aware that a certain area of space exists), so it’s very much worth a read.

Best of luck and happy trails!

xoxo, Aunt Scripty

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Cranial Nerves

Nerves supplying the body can be divided in to cranial and spinal. Cranial nerves emerge from the brain or brain stem and spinal from the spinal chord. There are 12 pairs of cranial nerves. They are components of the peripheral nervous system, with the exception of the optic nerve, as their axons extend beyond the brain to supply other parts of the body. They are named numerically from region of the nose (rostral) to back of the head (caudal). Here’s a brief overview of all twelve nerves and their basic functions.

I – The Olfactory Nerve. The cells of this nerve arise from the olfactory membrane of the nasal mucosa. The dendrites of the nerve cells project in to the olfactory mucosa. The axons of these cells combine to form the olfactory nerve. They join the brain at the olfactory bulb, located at the end nearest the nose. The fibres are short and lie deep and protected from casual injury. It is often found that loss or interference of sense of smell is due to blockage of the air passage leading to the olfactory mucosa, not due to nerve damage.

II – The Optic Nerve. This nerve connects the retina to the diencephalon of the brain. It is the only cranial nerve considered to be part of the central nervous system. This means the fibres are incapable of regeneration, hence why damage to the optic nerve produces irreversible blindness. Interestingly the eye's blind spot is a result of the absence of photoreceptor cells in the area of the retina where the optic nerve leaves the eye. I find the optic nerves easy to spot when looking at the brain from below as they form the optic chiasm. This is the point at which they cross and forms a clear ‘x’.

III- The Oculomotor Nerve. This nerve controls most of the eye’s movements including the constriction of the pupil and levitation of the eyelid. Damage to the nerve can cause double vision and inability to open the eye. A symptom of damage to this nerve is tilting of the head.

IV – The Trochlear Nerve. This nerve is a small somatic motor nerve and innervates the dorsal oblique muscle of the eye, responsible for allowing the eye to look down and up as well as internal rotations. Damage to the nerve can cause one eye to drift upwards in relation to the undamaged eye, meaning patients tilt their heads down to compensate.

V – The Trigeminal Nerve. This is the largest cranial nerve and is so called as it has three major divisions. It is sensory to the skin and deeper tissue of the face and motor to certain facial muscles, playing a large role in mastication.

VI – The Abducent Nerve. This nerve controls the movement of the lateral rectus muscle of the eye. It also plays a role in eye retraction for protection. Injury produces the inability to deviate the eyeball away from the midline of the body.

VII – The Facial Nerve. This nerve innervates the muscles of facial expression. It also functions in the conveyance of taste sensations from the front two thirds of the tongue. As well as this it can increase saliva flow through certain salivary glands.

VIII – The Vestibulocochlear Nerve. This nerve is named after the vestibular and cochlear components of the inner ear. It transmits information on sound and balance. Damage can lead to deafness, impaired balance and dizziness.

IX – The Glossopharyngeal Nerve. This nerve has any roles including the innervation of certain muscles of the palate of the mouth, certain salivary glands and the sensory mucosa of the root of the tongue, palate and pharynx. Damage can lead to difficulty swallowing as well as the loss of ability to taste bitter and sour things in humans.

X – The Vagus Nerve. This is a very important nerve and one frequently discussed when considering many important systems within the body. It is the longest of all cranial nerves and extends to supply the pancreas, spleen, kidneys, adrenals, and intestine. It has parasympathetic control of the heart and digestive tract as well as certain glands and involuntary muscles.

XI – The Accessory Nerve. This plays a role in neck turning and elevation of the scapula (shoulder). Muscle atrophy of the shoulder region indicates damage to this nerve.

XII – The Hypoglossal Nerve. This nerve’s name relates to the fact that is runs under the tongue, innervating the tongue’s internal and external musculature. It has important roles in speech, food manipulation and swallowing.

Theatrical poster for FARGO by Creative Partnership / Optic Nerve.

The Best Movie Posters of the 90’s, on the new episode of The Poster Boys. Designers Brandon Schaefer and Sam Smith reflect on their favorite one-sheets produced in the 90’s, discussing the posters that made impressions on them as kids, those that had a formative impact on their design sensibilities, and those that still hold up today for their branding, balance, use of photography, and iconic power, from THE ROCKETEER and HOME ALONE to FARGO and Akira Kurosawa’s DREAMS.

Visit theposterboys.tumblr.com to stream all episodes and view all images discussed on the show, and subscribe, rate, and review The Poster Boys on iTunes.

@tropicojewels01 is sending me these pickup lines and one of them was “your hand looks heavy. let me hold it for you.” so, naturally, i wrote this.

__________


“Your hand looks heavy,” Kai said, smirking. “Can I hold it for you?”

“What?” Cinder said, her eyes lifting from the lifeless android in front of her long enough to give him a confused look. She pursed her lips in thought. “That’s kind of an odd request, but, yeah, sure. I guess.” She took a screwdriver and unscrewed the mechanical limb. She snipped at the optic nerves and handed it to him. “Just make sure you don’t drop it.”

Kai stared blankly at the hand. “Oh,” he said, disappointed she didn’t catch up on the pickup line. “I’ll just, uh, go put this with the foot.” At least now he had two of Cinder’s limbs

Split movie mixes fact with fiction in a way that spreads misinformation

“In (The therapists) descriptions of DID she takes real stories, such as the real true story of a blind women who has alters who can see, but puts in untrue facts that they could see because “their optic nerves grew back because they believed they could see”“ when in reality this women had a form of brain-based blindness rather than eye-based blindness and therefore it did not effect her whole system. Source splitmoviehurts.com

Aside from the obvious demonization from the film this close mix of fact and fiction can cause a lot of confusion in the audience leaving them unsure what to believe. This mix of fact and fiction encourages the spread of misinformation and ultimately causes serious problems for advocates and educators

#DidYouKnow - The narrower the pupil in relation to the horizon, the greater accuracy of depth perception in peripheral vision? Pair that with the fact that the octopuses optical nerve fibers are behind retina and you get absolutely no blind spot which means an octopus can see everything that is going on in their environment. Pretty cool huh nation?! 📸: Gustavo Maqueda

Follow the largest octopus blog on Instagram: www.instagram.com/octonation

papalogia  asked:

💜💛💙

💜 (vague): Every time this person acts holier than thou bc they don’t get involved in discourse and sighs about how godawful ship discourse is and “why can’t we all stop fighting!!” I roll my eyes so hard that my optic nerve has 2 resettle after I’m done. 

  💛 (honest opinion): My favourite desi bitch!!! We’re ride or die at this point I’d probably come into like, satan n me discourse w/ popcorn just to see u slam someone. (Even tho SaM is the chillest famdom tbh)

💙  (confession): Once I thought I sat down on a ziploc bag full of weed on the bus and I almost cried bc I was a kid and also a straight A student who didn’t want to go to jail but it was actually just oregano. Anyway I was shook.

Daily poem 5

How do you program a biological computer to love?

First I tried shooting a beam of electrons at its heart
1’s and 0’s maliciously bouncing porn adds inside
the ventricles, spare code, ghosts in the machine
whispering up arteries.
It was mostly unresponsive, some people say
if you want to get a person’s attention,
make an impression. So I took micron laser
and signed my name, unresponsive, chiseled
portrait and credentials.
At wits end I asked friends about your interests,
maintain eye contact with the floating gory
eyeball, bundles of optic nerves laid into bands
of metal the python cord leading into the
abyss of you, the eye by trick of light, is blue.
Pay compliments and bring chocolates,
“Nice shirt… puce really suits you.”
I sparked a plug and whispered sparks
onto the transistors, and then there was
a clicking whirr, and a fan turned on. 

Keep reading

2

Just an update, night two here in the hospital. Heart is fine. Monitoring my brain now to see why I’m fainting so much (10 times total now since being in here. All while laying down.) I’m bed bound and have wires stuck on my head for an EEG. My left optic nerve has a pseudo tumor and I’m seeing the eye doctor about that today. Not sure when I’ll be coming home yet. I was in the heart hospital but now I’m on the neuro floor. I just want answers is all. Okay, I think that’s all. Passed out once writing this. Ugh gees. Thanks everyone for support. Means the world to me.

Tech Witches

Power crackles through the wires, running like blood through veins to strengthen warded firewalls, whisper through animated candles, and charge embedded sigils.  The aura of the screen shines through irises and optic nerves and lights up all those small neural galaxies, bringing dreams of lightning and fire and forged-metal wires, of liquid looped frames and the vibration of lossless voices.


the EGERIA® implant is more or less a wireless modem and CPU that is largely organic to make installation as unintrusive as possible (an injection of nanites) and uses the organic components of the brain to function. data storage is in the hippocampi, it uses the optic nerve for augmented reality projection and the cochlear nuclei to project sound signals as if you were hearing them.

external devices are still required to interact with the internet of 2064 and the implant (smartphones are perfect for this, sometimes you gotta turn down the volume on that music livestream coming directly into your brain) but the EGERIA® implant makes it a lot more accessible by providing a centralised processor, storage device, operating system (eOS) and internet connection. your devices are all powered by the EGERIA® implant and your apps and data are everywhere, because they’re in your head and are instantly available as long as the device is compatible.