Neurological disorder

All posts tagged Neurological disorder

Alice in Wonderland Syndrome

Posted by Mason I. Bilderberg (MIB) on January 7, 2013
Posted in: Brain Works, Educational, Medical, Science. Tagged: , , , , , , , , , . Leave a Comment

via examiner.com

f190792af99d26dbe81be25e8bffb3a3_250pxAlice-in-Wonderland-Syndrome, or AIWS, is a perceptual disorder where objects or people may seem to be out of proportion, different in size than they should be, colored strangely, or too far or too close away. The size disturbances include micropsia, where the object being looked at appears too small and macropsia, where objects seem too large. Sometimes, objects seem farther away than they should be, as in teleopsia.
If the problem is not in size or distance, it can even involve color, as in achromatopsia, where there is no perception of color. When the hallucination involves people, the person can appear too small, as in Lilliputian hallucinations (yes, this is the name of the disorder).

In a sufferer, the eye is normal and there are no defects that would lead to the perceptual distortions associated with the disorder. Instead, the problems lay in the brain. There are theories that the disorder can arise during Epstein-Barr viral infection, which causes infectious mononucleosis (IM).

Sufferers of chronic migraines have reported visual disturbances that occur prior to onset of migraine pain. AIWS is sometimes associated with these hallucinogenic migraines. The AIWS episodes can occur even without the pain of a migraine. It is not fully known why AIWS occurs, especially when it is in conjunction with migraines.

One other possible cause of AIWS is temporal lobe epilepsy. As the name implies, the temporal lobes of the brain are involved. The temporal lobes, which are at the sides of your brain, control the brain’s language center, and are an important area in auditory processing. Why AIWS may be associated with this form of epilepsy is also unknown.

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Seeing Things? Hearing Things? Many of Us Do

Posted by Mason I. Bilderberg (MIB) on November 9, 2012
Posted in: Brain Works, Educational, Human Perception, Psychology. Tagged: , , , , , , , , , . 1 comment

By OLIVER SACKS via NYTimes.com

HALLUCINATIONS are very startling and frightening: you suddenly see, or hear or smell something — something that is not there. Your immediate, bewildered feeling is, what is going on? Where is this coming from? The hallucination is convincingly real, produced by the same neural pathways as actual perception, and yet no one else seems to see it. And then you are forced to the conclusion that something — something unprecedented — is happening in your own brain or mind. Are you going insane, getting dementia, having a stroke?

In other cultures, hallucinations have been regarded as gifts from the gods or the Muses, but in modern times they seem to carry an ominous significance in the public (and also the medical) mind, as portents of severe mental or neurological disorders. Having hallucinations is a fearful secret for many people — millions of people — never to be mentioned, hardly to be acknowledged to oneself, and yet far from uncommon. The vast majority are benign — and, indeed, in many circumstances, perfectly normal. Most of us have experienced them from time to time, during a fever or with the sensory monotony of a desert or empty road, or sometimes, seemingly, out of the blue.

Many of us, as we lie in bed with closed eyes, awaiting sleep, have so-called hypnagogic hallucinations — geometric patterns, or faces, sometimes landscapes. Such patterns or scenes may be almost too faint to notice, or they may be very elaborate, brilliantly colored and rapidly changing — people used to compare them to slide shows.

At the other end of sleep are hypnopompic hallucinations, seen with open eyes, upon first waking. These may be ordinary (an intensification of color perhaps, or someone calling your name) or terrifying (especially if combined with sleep paralysis) — a vast spider, a pterodactyl above the bed, poised to strike.

Hallucinations (of sight, sound, smell or other sensations) can be associated with migraine or seizures, with fever or delirium. In chronic disease hospitals, nursing homes, and I.C.U.’s, hallucinations are often a result of too many medications and interactions between them, compounded by illness, anxiety and unfamiliar surroundings.

But hallucinations can have a positive and comforting role, too — this is especially true with bereavement hallucinations, seeing the face or hearing the voice of one’s deceased spouse, siblings, parents or child — and may play an important part in the mourning process. Such bereavement hallucinations frequently occur in the first year or two of bereavement, when they are most “needed.”

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Confabulation

Posted by Mason I. Bilderberg (MIB) on October 8, 2012
Posted in: Brain Works, Educational, Human Perception, Psychology. Tagged: , , , , , , , , . Leave a Comment

via Unnatural Acts that can improve your thinking: Confabulation

Have you ever told a story that you embellished by putting yourself at the center when you knew that you weren’t even there? Or have you ever been absolutely sure you remembered something correctly, only to be shown incontrovertible evidence that your memory was wrong? No, of course not. But you probably know or have heard of somebody else who juiced up a story with made-up details or whose confidence in his memory was shown to be undeserved by evidence that his memory was false.

Confabulation is an unconscious process of creating a narrative that is believed to be true by the narrator but is demonstrably false. The term is popular in psychiatric circles to describe narratives of patients with brain damage or a psychiatric disorder who make statements about what they perceive or remember. The narratives are known to be either completely fictional or in great part fantasy, but they are believed to be true by the patients.

Neurologist Oliver Sacks writes of a patient with a brain disorder that prevented him from forming new memories. Even though “Mr. Thompson” could not remember who Sacks was, each time Sacks visited him he created a fictional narrative about their previous encounters. Sometimes Sacks was a butcher Thompson knew when he worked as a grocer. A few minutes later, he’d recognize Sacks as a customer and create a new fictional narrative. Sacks described Thompson’s confabulations as an attempt to make meaning out of perceptions that he could only relate to events in long-term memory.

You might think: poor fellow; he has to construct his memories and fill in the blank parts with stuff he makes up. Yes, he does. But so do you, and so do I. There is an overwhelming amount of scientific evidence on memory that shows memories are constructed by all of us and that the construction is a mixture of fact and fiction. Something similar is true for perception. Our perceptions are constructions that are a mixture of sense data processed by the brain and other data that the brain supplies to fill in the blanks.

Now there is a body of growing scientific research that shows confabulation is not something restricted to psychiatric patients or gifted fantasizers who believe they were abducted by aliens for reproductive surgery. The evidence shows that many of the narratives each of us produce on a daily basis to explain how we feel, why we did something, or why we made a judgment that we made are confabulations, mixtures of fact and fiction that we believe to be completely true.

This research should give us pause. Many of us accuse others of making stuff up when they present arguments that are demonstrably full of false or questionable claims, but it’s possible that people who make stuff up aren’t even aware of it. They might really believe the falsehoods they utter.

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