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32

The IARC has concluded that cell phones are a "possible carcinogen" due to the amount of evidence going both directions. The gist of it is summarised on the website itself: Cell phones emit radiofrequency energy, a form of non-ionizing electromagnetic radiation, which can be absorbed by tissues closest to where the phone is held. The amount of ...


10

First of all, I am going to stay quite “general” as I understand you are not from the field. The aim of my post is really to provide some clarifications to your question. There are two types of strokes: ischemic (approx. 85%) and hemorrhagic (approx 15%). As you are speaking of “blood accumulated in the brain” I understand that you mean hemorrhagic stroke (...


10

This so-called sixth sense is called kinesthesia or proprioception. There are some slight differences between the two, in that kinesthesia only refers to moving parts, whereas your proprioceptive sense can identify the position of your body even when still. kin·es·the·sia awareness of the position and movement of the parts of the body by means of sensory ...


10

Memory is a complex cognitive function which relies on several neuronal pathways. Without wanting to go into too much details, the process of memorization is dependent on three different steps: encoding, storage and retrieval. Different brain regions are involved in the process of memorisation: hippocampus and mamillary bodies are the main brain regions (...


9

Exposure to ionizing radiation, such as from x-rays, is known to increase the risk of cancer. However, although many studies have examined the potential health effects of non-ionizing radiation from radar, microwave ovens, cell phones, and other sources, there is currently no consistent evidence that non-ionizing radiation increases cancer risk (1). Source: ...


9

The problem here is the over-simplified (and inaccurate) idea that Thiomersal = mercury, it's not, rather it is a compound (chemical formula: C9H9HgNaO2S) that has mercury atoms in it's molecules, the mercury vapors (Hg) are a different thing, chemically speaking. This means that mercury and Thiomersal will behave very differently in chemical terms, ...


7

First of all, your "main question" contains a lot of small other questions, which I think are difficult to answer as we are not your sister's neurologist (we haven't seen the MRI, we haven't examined her,etc...) But I will try to address some of your concerns: What are arachnoid cysts? Arachnoid cysts (AC) are a collection of cerebrospinal fluid (CSF) ...


7

No A cerebral hemorrhage (also spelled haemorrhage) is a type of intracranial hemorrhage that occurs within the brain tissue. It can be caused by brain trauma, or it can occur spontaneously in hemorrhagic stroke. Non-traumatic intracerebral hemorrhage (or hemorrhagic stroke) is a spontaneous bleeding into the brain tissue because of rupture of ...


6

I'll assume you're only asking about mechanoreceptors, else it gets too murky. Humans have four types of mechanoreceptors. Meissner corpuscle, innervated by RA1 (rapidly adapting type 1) nerve fibers. There are 2 of the fibers per square millimeter in the monkey finger (my source does not list it for humans), with 10 to 20 Meissner corpuscles per axon, ...


6

This study published in 2014 provides an excellent review of the physiological mechanisms of cerebral blood flow regulation (open access): Willie CK et al. Integrative regulation of human brain blood flow. J Physiol. 2014 Mar 1;592(5):841-59. doi: 10.1113/jphysiol.2013.268953. Their list of references includes a very exhaustive list of studies conducted on ...


6

What you're describing has been known since antiquity. What you first describe (an arc-like enlargening area of blurry vision) has been called a scintillating scotoma and artists and patients alike have tried to describe it with interesting results: It is important to note that this happens in both eyes simultaneously, so that the same part of the ...


6

Is it possible to forget our past(bad memories) through Electroconvulsive Therapy? No. To simplify somewhat, ECT is associated with: immediate general cognitive and memory dysfunction represented by disorientation (e.g. "Where am I? Why am I here? What's the date today?"): transient and generally resolves in a matter of 30-60 minutes after the procedure. ...


5

Most of the time it is critically important to realize that sleep deprivation is very often due to unrecognized sleep disorders. After a typical night's sleep, you may not feel restored and refreshed and be sleepy during the day, but be totally unaware that you are sleep-deprived or have a sleep disorder. You might tend to think, "It's just the stress of ...


5

There is, unfortunately, no yes or no answer to this, especially not on-line. However, these information can help: There can be various underlying causes of fainting, mostly cardiovascular or neurological. It is important to note that same pathophysiological mechanisms may be a part of different clinical syndromes. Some of these (classification adjusted for ...


5

The "fight or flight response" occurs under the control of the autonomic nervous system, which is to a great degree (but not completely) involuntary. The autonomic nervous system regulates certain body processes, such as blood pressure and the rate of breathing. This system works automatically (autonomously), without a person’s conscious effort. You can ...


5

Does carbon monoxide poisoning make you tired before it kills you? The symptoms of carbon monoxide poisoning can vary per person it affects, and it can also depend on the the levels of exposure to each person. The short answer would be yes, general fatigue and tiredness can be a symptom of carbon monoxide poisoning. I believe this is accurate for one ...


5

What worked for me (and many others!) was exercise. After trying many antidepressants, I tried running. What got me motivated was an old article that I read about a clinical trial done by the University of Wisconsin around 1980. (Sorry, I could not find it today). IIRC, half of the group was given Prozac with no exercise, and the other half ran but was not ...


4

Lowered brain activity in a PET scan isn't necessarily bad. It depends on what part of the brain is less active than usually and whether this is a permanent or transient state. Our brains are less active during sleep - that isn't a bad thing. Anyway, brain activity isn't just generally lowered during meditation. On the contrary. Functional brain mapping ...


4

Sleep irregularity In children, values for lower sleep duration were found to be strongly associated with increased metabolic risk. Although obese children did not display radically different total weekly sleep durations, compared with their normal-weight counterparts, analyses of SV throughout the week revealed that obese children were less likely to ...


4

I checked literature on this and found that following general measures are helpful to prevent acute mountain sickness, high altitude cerebral edema (HACE) and high altitude pulmonary edema (HAPE): These conditions generally occur at altitudes higher than 2500 meters. Beyond that, one should not ascend more than 300-500 meters per day. Slow ascent, e.g. ...


4

First, let's define retrograde amnesia carefully. You'll find many sources listing drugs that cause retrograde amnesia but they're using the term incorrectly. From http://www.human-memory.net/disorders_retrograde.html: Retrograde amnesia is a form of amnesia where someone is unable to recall events that occurred before the development of the amnesia, ...


4

If you have a look at one of the most famous reference book in neuroscience "Principles of neural science" by Kandel (Fifth Edition), on page 22: There is this figure: And here is the description of the figure (extracts): Most neurons in the vertebrate nervous system have several main features in common. The cell body contains the nucleus, the ...


4

There seems to be a misconception at the driving part of the question. Exercise has more effects (on the brain) than just stimulating a few synapses. That is indeed a vague and vastly incomplete conception. Since brain chemistry is by far not completely understood it is also quite premature to believe we would be able to define some kind of "optimal" ...


4

Three spots in the brain do not automatically mean three different symptoms. Even if those spots are abnormal, they do not necessary cause any damage. A doctor in the "2. MRI report" says there are: ...few bilateral parietal subcortical tiny white matter foci...warrant further evaluation to exclude possibility of early onset MS. So, there are 3 tiny ...


4

There are four cognitive symptom categories for Alzheimer's disease: aphasia, amnesia, apraxia, agnosia. These are broad categories that our brains handle somewhat separately. People frequently do sustain a brain injury to the left side of the head that damages his or her ability to process language and speech without affecting any other cognitive abilities. ...


4

When you put it that way... "...a cerebral circuit of evil..." ...no, that is absolutely ridiculous (no offense). In the human body (and generally in nature) there are only physical and biochemical mechanisms. All behaviours that are described by the behavioural sciences (e.g. psychology) can be interpreted by biochemical mechanisms. For example, if ...


4

Diffusion of water. Osmosis is movement of water across a membrane due to solute changes. In the case of diffusion tensor MRI, the whole point is that there is more diffusion along the same axis as white matter axons are traveling (either within or outside, but not across, those membranes), compared to a perpendicular axis. There isn't any net flow, it's ...


4

This claim probably derives from back-of-the-envelope calculations for cellular turnover rather than "organic material," and is quite inaccurate since some cells turn over very quickly and others last a very long time, making an average a poor summary statistic. I think this explanation for the root of the claim also makes sense given the exclusion of the ...


3

When drinking alcohol, the small water-soluble ethanol enters the bloodstream and moves around till it reaches the brain. Since it is a small molecule, it enters the blood-brain barrier and passes between brain cells (neurons) interfering with the neurotransmitters of the nervous system. Ethanol causes the release of Dopamine (Happiness Hormone) and stops ...


3

An accident left Derek Amato with a severe concussion and a surprising ability to play the piano. One theory is that his brain reorganized, making accessible existing memories of music. Another is that his brain no longer filters sensory input, enabling him to hear individual notes rather than melodies. http://www.popsci.com/science/article/2013-02/when-...


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