Tagged Questions

3
votes
1answer
45 views

Why does it hurt more when you touch a nerve directly?

I am not a biologist nor know much about biology (so please explain in layman's terms) however I have always been curious as to why this is. What causes the difference in pain between touching an ...
5
votes
1answer
46 views

Does frequency of eye blinking reveal anything about human biology/nervous system?

I'm looking at an output of a single dry sensor EEG headband with the sensor positioned above left eye. As a side effect of it's placement, the device picks up eye blinks, and some eye motion as ...
5
votes
1answer
45 views

Why do we yawn?

I've read a new study which suggests that yawning may help you keep a cool head. Also, the findings might hold some hope for sufferers of insomnia, migraines, and even epilepsy. Is there any ...
4
votes
1answer
53 views

What kinds of arousal can a human brain experience?

I've been reading about the new phenomenon called "arousal addiction". The context in which this term is used is Internet, Porn and/or video game addiction(cummulatively Internet Addiction Disorder - ...
4
votes
2answers
172 views

Effects of exercise on the brain

I am well aware of the phenomenon of neurogenesis induced by exercise, as well as the dopamine release that results from exercise. I am really interested in neuropsychology and the effects of exercise ...
3
votes
2answers
111 views

Physiological indicators of happiness and well being

If I understand it correctly, levels of serotonin in the brain can indicate if a person is happy. What other physiological measures indicate happiness or well being for a humans? I am looking for ...
5
votes
2answers
75 views

Is warmth/temperature sensed linearly or on a different scale?

I understand that the atmospheric temperature is sensed relative to external body temperature. However, is the sensation of warmth registered linearly, or is it on a logarithmic scale, similar to ...
8
votes
2answers
198 views

Do memories have mass?

If it were possible to live forever, would our brains grow infinitely with the number of memories that we store? Or would we remove old memories as we create new ones?
2
votes
3answers
140 views

Is there such thing as “half-life” of dopamine?

If a dopamine is released at T=0 and binds to receptor D2, what determines the time when the concentration of this neurotransmitter bound to the receptor reaches half of the original concentration? In ...
4
votes
1answer
93 views

Do effects of caffeine on human body change with habitual use?

I've been reading about homeostatic nature of a lot of neurobiological processes - the brain is trying to maintain a balance by desensitizing receptors, re-uptaking and breaking down ...
2
votes
0answers
112 views

Are inflammation and anxiety connected?

I've been reading a curious paper about the use of cannabis, and one of the passages piqued my interest: There’s also been a lot of work done on another constituent of marijuana, cannabinoid, ...
1
vote
0answers
30 views

Does Dorsal Raphe Nuclei firing pattern change in response to voluntary breathing?

I'm reading this paper, which discusses how Serotonin may be involved in motor functions of mammals: 5-HT and motor control: a hypothesis . The paper includes the following diagram of the Dorsal ...
1
vote
0answers
68 views

What triggers creative thought in humans?

Creativity, innovation and ideation. Is there something in the brain that makes the brain think that way, as opposed to "normal baseline". What triggers creative thought in humans?
3
votes
2answers
95 views

Can children restore brain cells?

By "children" I mean young people at the age of 10 or lower. I know that the adult brain cannot restore brain cells, but what about children? I mean, the brain must develop from a few cells to a 90 ...
8
votes
2answers
292 views

Why do the two hemispheres of the brain control the opposite sides of the body?

Why does the left hemisphere control the right and the right hemisphere control the left? I googled it but didn't find a good answer regarding this. Could someone explain? Does this adaptation help ...
1
vote
0answers
70 views

Why is membrane potential not zero at equilibrium?

For the squid giant axon, the membrane potential computed by the Goldman equation is -60mV. And the Nernst potentials are (the differences between the K+ and the Na+'s Nernst potential and the ...
4
votes
0answers
44 views

What light intensity determines the start/end of a photoperiod in humans?

I'm reading this article, which discusses the influence of Long Photoperiod (LP) and Short Photoperiod (SP) on melatonin production: HIOMT drives the photoperiodic changes in the amplitude of the ...
4
votes
1answer
151 views

Is there a relationship between Melatonin, Norepinephrine and depression in humans?

I'm reading a booklet on melatonin published in 1996, titled "Melatonin and the Biological Clock". This particular paragraph caught my attention and I would like to better understand what it means: ...
7
votes
3answers
162 views

What alternatives are there to the amyloid hypothesis?

Given the recent failure of the Bapi clinical trial, there is a lot of questions that have arised from he amyloid hypothesis. However, I can't really think of many other mechanisms that don't involved ...
6
votes
1answer
258 views

Is there a biological basis to physical attraction?

Is there something encoded within us that makes us attracted to, e.g., someone taller or shorter with blonde or brunette hair with green or blue eyes? Or, is this phenomenon completely based on ...
4
votes
2answers
76 views

What is the purpose of the adrenal medulla?

The adrenal medulla is less of a 'real' endocrine organ like the others in the endocrine system and much more an extension of the sympathetic nervous system. In fact, its chromaffin cells are modified ...
6
votes
1answer
112 views

Understanding Membrane / Resting Potential from the perspective of ions?

From wikipedia article RESTING potential: "there is no actual measurable charge excess in either side. That occurs because the effect of charge on electrochemical potential is hugely greater than ...
2
votes
1answer
137 views

Why apes started to contemplate and become altruistic? [closed]

I was asking this first on philosophy forums, but it is suggested, that answer could be found from evolutionary view of point, so here we go: Again my question raised when thinking of myths, their ...
5
votes
1answer
192 views

Is it purely the nervous system causing vaginal lubrication (arousal)?

My girlfriend was watching some documentary on TLC about a paralyzed woman getting pregnant. I believe that woman still has some feeling, as she spoke about feeling the effects of a bladder ...
6
votes
1answer
150 views

Why is the Patellar reflex not triggered when the tendon is extended slowly?

I have been previously told that the Patellar reflex (knee-jerk-reaction) exists to prevent the hyper-extension of the patellar tendon. Yet if the impact to the tendon is delivered slowly - i.e. by ...
14
votes
2answers
940 views

What actually happens when my leg 'falls asleep'?

Most people have experienced the temporary loss of feeling and tingling in their leg resulting from sitting in an abnormal position for a short while. Usually you get a loss of feeling in your leg ...
4
votes
1answer
84 views

What evidence gives clues to the physiological basis for conversion disorder?

Conversion disorder has a set of DSM diagnosis criteria, which, among other things, includes ruling out all neurological disease. However, as the media has shown us (and one could argue a biased ...
22
votes
3answers
3k views

How does the brain's energy consumption depend on mental activity?

What is the impact of mental activity on the energy consumption of the human brain? I am most interested in intellectually demanding tasks (e.g., chess matches, solving a puzzle, taking a difficult ...
4
votes
1answer
126 views

What are the constraints when growing an artificial brain?

Are there any experiments on growing artificial brains from brain tissue? What are the constraints? Will such tissue grown to the mass greater than that of human brain surpass it in intellect or it ...
10
votes
2answers
258 views

Could an “overactive” brain increase the chances of Alzheimer's Disease?

From Raichle ME. 2010. Two views of brain function. Trends in cognitive sciences 14: 180–90: Alzheimer’s disease (AD) is the most common cause of progressive cognitive decline and dementia in ...
14
votes
2answers
620 views

How and where, in the human brain, are memories stored?

Background I am a computer programmer who is fascinated by artificial intelligence and artificial neural networks, and I am becoming more curious about how biological neural networks work. Context ...
13
votes
8answers
3k views

Why have humans evolved much more quickly than other animals?

Humans have, in a relatively short amount of time, evolved from apes on the African plains to upright brainiacs with nukes, computers, and space travel. Meanwhile, a lion is still a lion and a ...
11
votes
1answer
187 views

Is it correct that the body only responds to the most painful stimulus?

I'm rather ashamed to say that this question is partly based on an episode of House. I have previously heard that, if there are multiple simultaneous painful stimuli, the mind will only feel the ...
0
votes
1answer
3k views

How reversible is decerebrate posturing caused by brain stem damage?

This is a follow-up question to How likely would Abraham Lincoln be to survive his wounds today? You don't have to see a CT scan or autopsy to know if the brainstem is injured (directly or ...
24
votes
4answers
593 views

Human perception of time depending on age

From what I can tell and what thus far all people with whom I discussed this subject confirmed is that time appears to "accelerate" as we age. Digging a little, most explanations I found basically ...
7
votes
1answer
91 views

What portions of the brain have drastic changes in activation when we “sense” someone is there?

I was watching an old Arnold Schwarzenegger movie ("Commando") where he plays an elite soldier (surprise). An enemy tries to sneak up on him, and Arnold says that he smelled the other guy ...
12
votes
2answers
482 views

How does a brain distinguish stimuli?

If all the brain ever "sees" is action potentials, how do we know that one set of action potentials denotes a flash of light, another one signifies a loud sound, etc ?
7
votes
1answer
150 views

What would be the conduction speed of A-alpha fibers, were they unmyelinated?

It's known (Hursh 1939) that myelinated axons exhibit the behavior v = 6d, where v is the propagation speed [m/s] and d is the axon diameter [μm]. A related relation for unmyelinated axons is ...
12
votes
1answer
619 views

What causes REM atonia to be lost in sleepwalking?

I understand that in normal REM sleep the voluntary muscles are in effect paralysed in order to prevent an individual acting out their dreams. This paper indicates that there are likley to be ...
13
votes
2answers
241 views

How is temperature sensed?

Can anyone summarize the mechanism by which when an object of a given temperature is placed in contact with, say, the skin on a human fingertip, the average speed of the particles of the object is ...
5
votes
1answer
97 views

Latency to audition in human beings?

On average, in a human being with no neurological deficits, how long does it take for a sound which is sensed in the ear to reach the cortex? Which brainstem structures are most responsible for the ...
15
votes
2answers
1k views

How do the brain and nerves create electrical pulses?

I have heard that information is sent between the brain and peripheral nerves via electrical pulses or signals, but I don't understand how they create them in the first place.
11
votes
2answers
313 views

Do human beings have pheromone receptors?

What is the current consensus on whether or not humans have receptors that detect pheromones? If there are purported receptors, in what anatomical areas are they located? With what organ systems do ...