Dicho eso, este libro nos cuenta la historia de Vee, una chica que siempre ha estado un poco tras bambalinas y no toma muchos riesgos. Que no fue para nada lo que esperaba. Nerve es un juego peligroso que saca lo peor de algunas personas. Esta novela de Jeanne Ryan no decepciona, alcanza todas las expectativas e incluso las supera.
En general, Nerve es un libro que no puedes parar de leer. View all 4 comments. Nov 27, Frankie Lovely rated it did not like it Shelves: Ridiculous or perhaps not quite ridiculous enough? NERVE is an online phenomenon where players log on and complete dares for money and prizes. By all definitions, Vee is a "watcher" and not a "player" in the worl 1 star In a Word: But after seeing the guy she likes kiss someone else, Vee decides that she is through being backstage in her own life and decides to take a risk and play.
What I did like I really like the concept of this story. We live so much of our lives constantly connected to the internet these days that this futuristic concept seems at first very believable. I could absolutely see an online game like this popping up in reality. I also enjoyed the beginning of this story. Vee was an interesting character and I was excited to watch her step outside of her comfort zone in some wild, awkward, and embarrassing ways.
What I did not like The first few dares were very fun to read about. Embarrassing dares that would be enjoyable for the watchers of the games. Yeah, it sucks for the players, but who cares? As the dares increased in difficulty, I had a really hard time connecting with the story. I wanted either more super embarrassing dares and a really nice coming of age story to go along with it ….. Or I wanted wild, freeing, high adrenalin craziness. What I got was boring and farfetched slow moving situations. I seriously found myself rewriting this book in my head to make sense I do that sometimes when I'm not willing to accept defeat and dnf a book.
Really and truly … it was boring. They are all pretty much not worth mentioning. In Conclusion This book was nothing to write home about. It was boring, farfetched, ridiculous, weird and plain. If you want to read a decent book with a similar premise, I would suggest Panic by Lauren Oliver. Very similar but in my opinion, a better application of the underlying concept. View all 14 comments. Aug 12, Kate GirlReading rated it really liked it Shelves: It was super fast paced and I ended up devouring it in one sitting.
Despite it being pretty ridiculous in many ways, I found the plot to be extremely gripping and overall a really entertaining read! I will s 3.
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I will say that the ending was inconclusive and therefore pretty frustrating and the prologue seemed to have next to no explanation or connection to the rest of the book but nonetheless, I ended up thoroughly enjoying reading this I'm intrigued to see what the movie will be like! View all 5 comments. I saw it first and liked it very much. From the very beginning, the book is a whole different thing.
View all 6 comments. Feb 13, Kaya Dimitrova rated it really liked it Shelves: Aug 06, Lexie rated it it was ok Shelves: Reviewed at The Honest Bookclub. Alright, here's the deal: The only alternative, really, is adopting a nihilist senselessness-is-all-there-is approach. But given how heavily this book relied on material possessions, fame, voyeurism, looks, boys, looks, boys, and looks A senseless book about a cast of senseless characters making senseless decisions throughout. It's exactly what it says on the cover: And not to be misunderstood - this is a magnificent concept. Partly because there's a part of your brain that desperately wishes something akin to Nerve was real if you're a demented Gryffindor, at least , even knowing full-well that you wouldn't actually participate.
What, then, seems to be the problem? Swap in other characters instead of the ones in this book and we've got ourselves a fully enjoyable experience. Because Nerve is told through the eyes of Vee. And however you try to spin it believe me, I've spun so much I got dizzy , Vee is problematic.
She is problematic because she is talked into Nerve by a boy, perseveres because of another boy, and then sticks around for another boy - all the while making sure to point out that if it wasn't for [boy], she'd never have made it this far. That, Vee, would have been what we call a good thing. She is problematic because resents her friends for her own lack of sound judgment.
She is problematic because she's one jeepers! Which, incidentally, is the very premise of Nerve as a novel. I've raged and raged against the trope that being shy is a defect of character and that not being the center of attention means you're doing something wrong. But in the interest of once-more-with-feeling: Piling up living-tropes-in-character-form as all the side characters doesn't help, either. And now that I've thoroughly picked the book apart, a one-eighty: And for putting me in the position of easily the most irritating stratum in the book - the Watchers - and making me enjoy the experience and genuinely wonder what happens next - the book does, after all, earn a tentative pass.
The movie, however, looks amazing. But I'm by no means a movie aficionado, so I have low standards and nothing to compare it to. Keep this in mind at all times and you will never get horribly lost on my account. Oct 26, lucie rated it liked it Shelves: What can happen in one night? How far would you go to get what you want the most? Nerve was fun, suspensefull and addictive read. The dares were simple and stupid and I enjoyed them view spoiler [my favorite is probably how Ian had to get freebie hide spoiler ] - but only at the beginning.
No fun, too much drama, boring. Vee What can happen in one night? Vee - I understand why she signed up for the game and I liked to watch how she became more confident thanks these dares. I could expect that. I mean, it takes time obviously after Nerve when Vee is haunted by one of her Watchers.
It is not one of my favorite books but I think I will re-read it some day. If you want to read it just because you liked the movie. If you like Hunger Games and you want to read something similar. The only thing that the movie and this book have in common is the idea of truth and dare game. I wanted to watch Nerve long time before I have known there is a book for one simple reason: The character he plays in the movie is totally my dream boyfriend.
Aug 02, Inge rated it liked it Shelves: Re-reads come with risks. They can be really fun, but they can also turn some of your favourites into… not-so-favourites. And sadly, this is also the case with Nerve. While the premise still sounds really exciting, the ex 2. While the premise still sounds really exciting, the execution somehow falls as flat as a pancake. I had the same problem with Panic , of a similar premise which I ended up hating.
It was still a very easy and fun read, and you still want to turn the pages as fast as you can to see how the story ends. But the main character still had the personality of a paper bag and the excitement of the dares just seems to fall flat on paper, not to mention the insta-love was so high and so fast that I needed a seatbelt to keep up with it.
That was quite the ride! Nerve was thrilling, exhilarating and kept me reading for hours, not wanting to put the book down. You just had to know what was coming, what the next dare was going to be, how everyone was going to react.
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It was exciting up until the very end. NERVE is a new game. Millions of people around the world watch videos of other people performing dares, each one more challenging than the next. So when the dares get really crazy, why on earth would you play? Because of the prizes. So what have you got to lose? This is mistake number one. Mistake number two is continuing the idiotic dares for the free stuff. Like it was run by pesky teenagers with smart-ass comments. The virtual thing is always a bonus for me. A sequel would be nice. Right now would be nice.
Mar 06, Giselle rated it liked it Shelves: When the synopsis for Jeanne Ryan's Nerve was first brought to light, it instantly became a novel I had very high hopes for. Talk of high stakes dares broadcasted online by a game that seems to personally know its players - this screams intensity, excitement, and a heck of a lot of entertainment.
While it does deliver on the entertainment front, it leaves a lot to be desired when it comes to its promise of exhilarating suspense. Does it turn deadly? But this doesn't happen until near the en When the synopsis for Jeanne Ryan's Nerve was first brought to light, it instantly became a novel I had very high hopes for.
But this doesn't happen until near the end, saving it all for the climax. What was I expecting? More blood, that's for sure; more danger, more horrifying situations, more serious consequences. Definitely something a lot more sinister than singing in a cafe, or asking people for condoms. When dare after dare ended up being as trivial as the last, I resigned myself to the fact that this simply was not going to be as suspenseful as I had previously imagined.
Nonetheless, I can't say I didn't secretly take pleasure from the antics the characters were put through. It was entertaining, just not exactly thrilling. Once we get to the finale and things start to get darker, I finally got a glimpse of what I had hoped this whole novel would be: The stakes are sky high, and the level of anxiety rises tremendously.
It also brings about a lot of new questions regarding the integrity of this whole game. This "anonymous" organization does have quite an ominous vibe, I just wish it was introduced much sooner. Like your usual action film, Nerve is highly plot-driven and suffers from a lack in characterization as well as true depth. While I can't say I particularly cared for our main characters in any strong sense, I can't even begin to distinguish the numerous supporting roles that all seem to blend together; like a big cast of extras.
The absence of character development combined with insta-love also causes the romance to feel a bit stale. Aside from the characters, the plot itself doesn't have very much substance when you look under the surface either. History of past games would have given the idea more credibility, and how the games are actually constructed without raising very obvious red flags for the parents or better yet, the law, would have helped mend some very questionable logical flaws that arise when you put some thought into it.
There is a hidden message inside this novel that I found quite thought provoking, on how consumerism has such control over us. We easily succumb to material things and the promise of money. I was surprised by the amount of truth there was in the plot. We're in a culture where consumerism can turn around and destroy us, turning us into unthinking automatons. How far would YOU go to get what you want the most, especially when it's being dangled right in front of you?
Where this book failed to engage me at first, it made up for a lot of it during the last part. When it all comes to an end we're left with intriguing hints on where it will go from here; not to mention a gazillion questions regarding this mysterious entity called Nerve. It's a fun novel, and great if you're looking for a fast paced read with tons of mystery and action. For more of my reviews, visit my blog at Xpresso Reads View all 7 comments. Aug 04, Chelsea chelseadolling reads rated it liked it.
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There were parts of this that I really liked, and parts of it that I thought were really dumb. I definitely have higher hopes for the movie though because it seems like the movie is going to have much cooler tasks for the players Aug 16, Kyoko SWords rated it liked it. Este libro es un mehhh O sea, no es que me aburriese. Sus motivaciones, personalmente, me daban era grima. El final es otro mehhh. Es decir, que me quedo exactamente igual a como estaba antes de leerlo. El mensaje puede ser interesante, pero el contenido no le da peso. Jan 03, Elizabeth Sagan rated it it was ok.
Long story short, the book was so bad I had no desire to watch the movie anymore. Jan 20, Isaa Jason rated it liked it. The last pages.. Don't really ship it. But also don't rip it. I just don't care. A high-stakes online game of dares turns deadly When Vee is picked to be a player in NERVE, an anonymous game of dares broadcast live online, she discovers that the game knows her.
They tempt her with prizes taken from her ThisIsMe it's like facebook and instagram in one page and team her up with the perfect boy, sizzling-hot Ian. At first it's exhilarating--Vee and Ian's fans cheer them on to riskier dares with higher stakes. But the game takes a twisted turn when they're directed to a secret location with five other players for the Grand Prize round. Suddenly they're playing all or nothing, with their lives on the line. This book was pretty good. I really loved the first part of the book. Everything was going on a good tempo. Like a 5 star book. I just really didn't liked the ending.
It was to fast, i didn't knew what was happening, and i don't have the feeling that this shouldn't had been a stand-alone. The plot it self was pretty cool. When i started reading, i was already thinking that this was going to be my new fave stand-alone. Not because it's bad. Because i don't have the feeling that i read a stand-alone. Because things are not done yet, some Characters have still thing to do.
And we don't see that. The is alot of action, and we keep going. The action starts really fast. And the plot keeps moving, and you really wanne know what happens nexts. And what the nexst dare is. I say go read it. The movie is comming out really soon! And if you ask me, it looks better then book.
And the book is good! I love Vee except in the end. She is so funny and real. Vee has awesome sense of humor. She also talks about things teenagers talk about. Things like shoes and tv-shows like True blood. Vee is also very smart, she just forgets that sometimes. Making her self do stupid things. I do not know exactly what Vee for girl is. I really do not know. And therefore I would like more. I think there can be told much more, and can get much more information about the character's. I didn't trusted in the first place. I also didn't liked him or anything.
I mean, i didn't hated him. I just did not knew what to think of him. And that feeling is still here.
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I hate this guy. Tommy is like that sneaky jelous guy, who doesn't says anything. But is planning your death in his head. This girl guys, this girl i liked. We don't know much about her. But i liked her alot. And really didn't liked the fact that we don't get more of her. Oh damn, i hate her. I hate her so much. If she was real, oh damn.. This girl was anyoing. She has no heart and is a ass. But we simply know too little about them. And I think that thats just sad.
Those who seem desperate for it are the people that others least want to see.
Kid reviews for Nerve
Geez, why don't i tell him what brand of tampons i use while i'm at it? Turning my hot face away from the door, i raise my middle fingers to the dark room. That is the thing what makes this book 3,8 stars. Jan 03, Lala BooksandLala rated it really liked it Shelves: Whoa, I was totally on the edge of my seat the whole time. If you liked Panic by Lauren Oliver, check this one out too. View all 3 comments. Vi je uvek iza scene,uvek u senci drugih,nikada glavna zvezda. Kako se igra udaljava,dolazi u sukob sa prijateljima,roditeljima, samom sobom.
Ja sam neko ko ima stav. Koga gledaju hiljade ljudi. Mogla bih da se udavim u ovom tipu. Jun 11, Cristina rated it it was amazing. Nerve is seriously such an amazing book. I could not put it down, literally! I stayed up until 4 am reading because I just had to finish it. I kept telling myself "just one more chapter! Needless to say, I showed up at work at 6 am, a total zombie, but it was sooo worth it! And if I had it all to do over again, I'd do it! I absolutely am head over heels for this book! The story was so amazing! In some ways it reminded me of Hunger Games freaking amazing!!!
I loved how the author combined social networking site's think facebook! I can only imagine if a game of real life Dare's was created from my facebook posts, and broadcast live for the world to see. I am pretty certain it would involve me actually eating glitter! The Dare's started off low stakes, and got pretty intense! I was flipping through the pages as fast as possible to see if Vee would jump through their hoops, or walk away from the game and all the incredible swag. If they are both equal to their charges, then the operation will cancel itself out. This effect is referred to as summation.
There are two types of summation: Spatial summation requires several excitatory synapses firing several times to add up, thus causing an axon discharge. It also occurs within inhibitory synapses, where just the opposite will occur. In temporal summation, it causes an increase of the frequency at the same synapses until it is large enough to cause a discharge.
Spatial and temporal summation can occur at the same time as well. The neurons of the brain release inhibitory neurotransmitters far more than excitatory neurotransmitters, which helps explain why we are not aware of all memories and all sensory stimuli simultaneously. The majority of information stored in the brain is inhibited most of the time. When excitatory synapses exceed the number of inhibitory synapses there are, then the excitatory synapses will prevail over the other. The same goes with inhibitory synapses, if there are more inhibitory synapses than excitatory, the synapses will be inhibited.
To determine all of this is called summation. Neurons can be classified according to their electrophysiological characteristics note that a single action potential is not enough to move a large muscle, and instead will cause a twitch. Tonic or regular spiking: Some neurons are typically constantly or tonically active. Some neurons are notable for their fast firing rates. For example, some types of cortical inhibitory interneurons, cells in globus pallidus. Action potentials of some neurons are more narrow compared to the others. For example, interneurons in the prefrontal cortex are thin-spike neurons.
The central nervous system is the control center for the body. It regulates organ function, higher thought, and movement of the body. The central nervous system consists of the brain and spinal cord. When a nerve is stimulated the resting potential changes. Examples of such stimuli are pressure, electricity, chemicals, etc. Different neurons are sensitive to different stimuli although most can register pain. The stimulus causes sodium ion channels to open. The rapid change in polarity that moves along the nerve fiber is called the "action potential. If threshold does not occur, then no action potential can occur.
This moving change in polarity has several stages:. When the potassium ions are below resting potential mV. Since the cell is hyper polarized, it goes to a refractory phrase. The brain is found in the cranial cavity. Within it are found the higher nerve centers responsible for coordinating the sensory and motor systems of the body forebrain. The brain stem houses the lower nerve centers consisting of midbrain, pons, and medulla ,. The pons houses the control centers for respiration and inhibitory functions. Here it will interact with the cerebellum. The cerebrum, or top portion of the brain, is divided by a deep crevice, called the longitudinal sulcus.
The longitudinal sulcus separates the cerebrum in to the right and left hemispheres. In the hemispheres you will find the cerebral cortex, basal ganglia and the limbic system. The two hemispheres are connected by a bundle of nerve fibers called the corpus callosum. The right hemisphere is responsible for the left side of the body while the opposite is true of the left hemisphere.
Each of the two hemispheres are divided into four separated lobes: Located deep to the temporal lobe of the cerebrum is the insula. The cerebellum is the part of the brain that is located posterior to the medulla oblongata and pons. It coordinates skeletal muscles to produce smooth, graceful motions. The cerebellum receives information from our eyes, ears, muscles, and joints about what position our body is currently in proprioception.
It also receives output from the cerebral cortex about where these parts should be. After processing this information, the cerebellum sends motor impulses from the brain stem to the skeletal muscles. The main function of the cerebellum is coordination. The cerebellum is also responsible for balance and posture. It also assists us when we are learning a new motor skill, such as playing a sport or musical instrument. Recent research shows that apart from motor functions cerebellum also has some emotional role.
The Limbic System is a complex set of structures found just beneath the cerebrum and on both sides of the thalamus. It combines higher mental functions, and primitive emotion, into one system. It is often referred to as the emotional nervous system. It is not only responsible for our emotional lives, but also our higher mental functions, such as learning and formation of memories.
The Limbic system explains why some things seem so pleasurable to us, such as eating and why some medical conditions are caused by mental stress, such as high blood pressure. There are two significant structures within the limbic system and several smaller structures that are important as well. Memory is defined as: The mental faculty of retaining and recalling past experiences, the act or instance of remembering recollection. Learning takes place when we retain and utilize past memories. Overall, the mechanisms of memory are not completely understood.
Brain areas such as the hippocampus, the amygdala, the striatum, or the mammillary bodies are thought to be involved in specific types of memory. For example, the hippocampus is believed to be involved in spatial learning and declarative learning learning information such as what you're reading now , while the amygdala is thought to be involved in emotional memory. Damage to certain areas in patients and animal models and subsequent memory deficits is a primary source of information. However, rather than implicating a specific area, it could be that damage to adjacent areas, or to a pathway traveling through the area is actually responsible for the observed deficit.
Further, it is not sufficient to describe memory, and its counterpart, learning, as solely dependent on specific brain regions. Learning and memory are attributed to changes in neuronal synapses, thought to be mediated by long-term potentiation and long-term depression. The process of transferring information from short term to long term memory involves the encoding or consolidation of information.
This is not a function of time, that is, the longer the memory stays in the short term the more likely it is to be placed in the long term memory. On organizing complex information in short term before it can be encoded into the long term memory, in this process the meaningfulness or emotional content of an item may play a greater role in its retention in the long term memory. The limbic system sets up local reverberating circuits such as the Papez's Circuit.
Episodic memory represents our memory of events and experiences in a serial form. It is from this memory that we can reconstruct the actual events that took place at a given point in our lives. Semantic memory, on the other hand, is a structured record of facts, concepts, and skills that we have acquired. The information in the semantic memory is derived from our own episode memory, such as that we can learn new facts or concepts from experiences. Information for short term memory is stored in long term memory by rehearsal. The repeated exposure to a stimulus or the rehearsal of a piece of information transfers it into long term memory.
Experiments also suggest that learning is most effective if it is distributed over time. Deletion is mainly caused by decay and interference. Emotional factors also affect long term memory. However, it is debatable whether we actually ever forget anything or whether it just sometimes becomes increasingly difficult to retrieve it. Information may not be recalled sometimes but may be recognized, or may be recalled only with prompting.
This leads us to the third operation of memory, information retrieval. In recall, the information is reproduced from memory. In recognition the presentation of the information provides the knowledge that the information has been seen before. Recognition is of lesser complexity, as the information is provided as a cue. However, the recall may be assisted by the provision of retrieval cues which enable the subject to quickly access the information in memory.
Long-term potentiation LTP is the lasting enhancement of connections between two neurons that results from stimulating them simultaneously. Since neurons communicate via chemical synapses, and because memories are believed to be stored by virtue of patterns of activation of these synapses, LTP and its opposing process, long-term depression, are widely considered the major cellular mechanisms that underlie learning and memory. This has been proven by lab experiments. When one of the chemicals involved PKMzeta, it will be discussed later is inhibited in rats, it causes retrograde amnesia with short term memory left intact meaning they can't recall events from before the inhibitor was given.
By enhancing synaptic transmission, LTP improves the ability of two neurons, one presynaptic and the other postsynaptic, to communicate with one another across a synapse. The precise mechanism for this enhancement isn't known, but it varies based on things like brain region, age and species.
The end result of LTP is a well established neural circuit that can be called upon later for memory. LTP is generally divided into three parts that occur sequentially: Short-term potentiation isn't well understood and will not be discussed. Induction happens when a short-lived signal triggers that phase to begin. Maintenance corresponds to the persistent biochemical changes that occur in response to the induction of that phase. Expression entails the long-lasting cellular changes that result from activation of the maintenance signal.
Each phase of LTP has a set of mediator molecules that dictate the events of that phase. These molecules include protein receptors, enzymes, and signaling molecules that allow progression from one phase to the next. In addition to mediators, there are modulator molecules that interact with mediators to fine tune the LTP. Modulators are a bit beyond the scope of this introductory book, and won't be discussed here.
E-LTP induction begins when the calcium inside the postsynaptic cell exceeds a threshold. When a stimulus is applied to the presynaptic neuron, it releases a neurotransmitter, typically glutamate, onto the postsynaptic cell membrane where it binds to AMPA receptors, or AMPARs. This causes an influx of sodium ions into the postsynaptic cell, this short lived depolarization is called the excitatory postsynaptic potential EPSP and makes it easier for the neuron to fire an action potential.
If EPSPs are reaching the cell before the others decay, they will add up. When the depolarization reaches a critical level, NMDA receptors lose the magnesium molecule they were originally plugged with and let calcium in. The rapid rise in calcium within the postsynaptic neuron trigger the short lasting activation of several enzymes that mediate E-LTP induction. They then carry out phosphorylation that underlies E-LTP expression. This is achieved by having a pool of nonsynaptic AMPA receptors adjacent to the postsynaptic membrane.
When the appropriate stimulus arrives, the nonsynaptic AMPA receptors are brought into the postsynaptic membrane under the influence of protein kinases. AMPA receptors are one of the most common type of receptors in the brain. Their effect is excitatory. By adding more AMPA receptors, and increasing their activity, future stimuli will generate larger postsynaptic responses. Late LTP is also associated with the presynaptic synthesis of synaptotagmin and an increase in synaptic vesicle number, suggesting that L-LTP induces protein synthesis not only in postsynaptic cells, but in presynaptic cells as well.
This is discussed under "retrograde messenger" below. Upon activation, ERK may phosphorylate a number of cytoplasmic and nuclear molecules that ultimately result in the protein synthesis and morphological changes associated with L-LTP. These chemicals may include transcription factors such as CREB. ERK-mediated changes in transcription factor activity may trigger the synthesis of proteins that underlie the maintenance of L-LTP.
PKMzeta is one such molecule. When this molecule is inhibited in rats, they experience retrograde amnesia where you can't recall previous events but short term memory works fine. They are though to increase postsynaptic dendritic spine number, surface area and sensitivity to the neurotransmitter associated with L-LTP expression.
Retrograde signaling is a hypothesis that attempts to explain that, while LTP is induced and expressed postsynaptically, some evidence suggests that it is expressed presynaptically as well. The hypothesis gets its name because normal synaptic transmission is directional and proceeds from the presynaptic to the postsynaptic cell. For induction to occur postsynaptically and be partially expressed presynaptically, a message must travel from the postsynaptic cell to the presynaptic cell in a retrograde reverse direction. Once there, the message presumably initiates a cascade of events that leads to a presynaptic component of expression, such as the increased probability of neurotransmitter vesicle release.
Retrograde signaling is currently a contentious subject as some investigators do not believe the presynaptic cell contributes at all to the expression of LTP. Even among proponents of the hypothesis there is controversy over the identity of the messenger. Language depends on semantic memory so some of the same areas in the brain are involved in both memory and language.
Articulation, the forming of speech, is represented bilaterally in the motor areas. However, for most individuals, language analysis and speech formation take place in regions of the left hemisphere only. The two major cortical regions involved are:. Broca's area is located just in front of the voice control area of the left motor cortex. This region assembles the motor sequencing of language, speech and writing. For example, patients with lesions in this area:. Wernicke's area is part of the auditory and visual associations cortex. This region is responsible for the analysis and formation of language content.
There are several well known diseases that are disorders of the limbic system. Several are discussed here. An increased dopamine DA response in the limbic system results in schizophrenia. DA may be synthesized or secreted in excess, DA receptors may be supersensitive, and DA regulatory mechanism may be defective. Symptoms are decreased by drugs which block DA receptors. Symptoms of schizophrenia are:.
Depression is the most common major mental illness and is characterized by both emotional and physical symptoms. Symptoms of depression are:. The cause of depression and its symptoms are a mystery but we do understand that it is an illness associated with biochemical changes in the brain. A lot of research goes on to explain that it is associated with a lack of amines serotonin and norephinephrine. Therefore pharmacological treatment strategies often try to increase amine concentrations in the brain.
One class of antidepressants is monoamine oxidase inhibitors. Mono amine oxidase is an enzyme that breaks down your amines like norephinephrine and serotonin. Because the antidepressants inhibit their degradation they will remain in the synaptic cleft for a longer period of time making the effect just as if you had increased these types of neurotransmitters. A newer class of antidepressants is selective serotonin reuptake inhibitors SSRI's.
With SSRI's decreasing the uptake of serotonin back into the cell that will increase the amount of serotonin present in the synaptic cleft. SSRI's are more specific than the monoamine oxidase inhibitors because they only affect serotonergic synapses. Manic depression, also known as bipolar disorder, displays mood swings between mania and depression. The limbic system receptors are unregulated. Drugs used are unique mood stabilizers. These diseases selectively attack CA1, which effectively cuts through the hippocampal circuit.
A connection between autism and the limbic system has also been noted as well. I was 42 years old when my life changed forever. I had a stroke. As an avid viewer of medical programs on television I assumed that I would have physical therapy for my paralyzed left side and get on with my life. No one ever mentioned pain or the possibility of pain, as a result of the stroke.
I did experience unusual sensitivity to touch while still in the hospital, but nothing to prepare me for what was to come. The part of my brain that is damaged is the Thalamus. This turns out to be the pain center and what I have now is an out of control Thalamus, resulting in Thalamic Pain syndrome, also called Central Pain Syndrome. This means that 24 hours a day, seven days a week, my brain sends messages of pain and it never goes away.
I am under the care of physicians, who not only understand chronic pain, but are also willing to treat it with whatever medications offer some help. None of the medications, not even narcotic medications, take the pain away. They just allow me to manage it so I can function. The peripheral nervous system includes 12 cranial nerves 31 pairs of spinal nerves.
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It can be subdivided into the somatic and autonomic systems. It is a way of communication from the central nervous system to the rest of the body by nerve impulses that regulate the functions of the human body. CN X receives visceral sensory information from the thorax and abdomen, and CN XI is responsible for innervating the sternocleidomastoid and trapezius muscles, neither of which is exclusively in the head.
Spinal nerves take their origins from the spinal cord. They control the functions of the rest of the body. In humans, there are 31 pairs of spinal nerves: The naming convention for spinal nerves is to name it after the vertebra immediately above it. Thus the fourth thoracic nerve originates just below the fourth thoracic vertebra. This convention breaks down in the cervical spine.
The first spinal nerve originates above the first cervical vertebra and is called C1. This continues down to the last cervical spinal nerve, C8. There are only 7 cervical vertebrae and 8 cervical spinal nerves. The remainder of the thoracic spinal nerves, T3 through T12, do little recombining. They form the intercostal nerves , so named because they run between the ribs. For points of reference, the 7th intercostal nerve terminates at the lower end of the sternum, also known as the xyphoid process.
The 10th intercostal nerve terminates at the umbilicus, or the belly button. The somatic nervous system is that part of the peripheral nervous system associated with the voluntary control of body movements through the action of skeletal muscles, and also reception of external stimuli.
The somatic nervous system consists of afferent fibers that receive information from external sources, and efferent fibers that are responsible for muscle contraction. The somatic system includes the pathways from the skin and skeletal muscles to the Central Nervous System. It is also described as involved with activities that involve consciousness. The basic route of the efferent somatic nervous system includes a two neuron sequence.
The first is the upper motor neuron, whose cell body is located in the precentral gyrus Brodman Area 4 of the brain. It receives stimuli from this area to control skeletal voluntary muscle. The upper motor neuron carries this stimulus down the corticospinal tract and synapses in the ventral horn of the spinal cord with the alpha motor neuron, a lower motor neuron. The upper motor neuron releases acetylcholine from its axon terminal knobs and these are received by nicotinic receptors on the alpha motor neuron.
The alpha motor neurons cell body sends the stimulus down its axon via the ventral root of the spinal cord and proceeds to its neuromuscular junction of its skeletal muscle. There, it releases acetylcholine from its axon terminal knobs to the muscles nicotinic receptors, resulting in stimulus to contract the muscle. The somatic system includes all the neurons connected with the muscles, sense organs and skin. It deals with sensory information and controls the movement of the body. The Autonomic system deals with the visceral organs, like the heart, stomach, gland, and the intestines.
It regulates systems that are unconsciously carried out to keep our body alive and well, such as breathing, digestion peristalsis , and regulation of the heartbeat. The Autonomic system consists of the sympathetic and the parasympathetic divisions. Both divisions work without conscious effort, and they have similar nerve pathways, but the sympathetic and parasympathetic systems generally have opposite effects on target tissues they are antagonistic. By controlling the relative input from each division, the autonomic system regulates many aspects of homeostasis.
One of the main nerves for the parasympathetic autonomic system is Cranial Nerve X, the Vagus nerve. The sympathetic nervous system activates what is often termed the fight or flight response, as it is most active under sudden stressful circumstances such as being attacked. This response is also known as sympathetico-adrenal response of the body, as the pre-ganglionic sympathetic fibers that end in the adrenal medulla but also all other sympathetic fibers secrete acetylcholine, which activates the secretion of adrenaline epinephrine and to a lesser extent noradrenaline norepinephrine from it.
Therefore, this response that acts primarily on the cardiovascular system is mediated directly via impulses transmitted through the sympathetic nervous system and indirectly via catecholamines secreted from the adrenal medulla. Western science typically looks at the SNS as an automatic regulation system, that is, one that operates without the intervention of conscious thought.
Some evolutionary theorists suggest that the sympathetic nervous system operated in early organisms to maintain survival Origins of Consciousness, Robert Ornstein; et al. One example of this priming is in the moments before waking, in which sympathetic outflow spontaneously increases in preparation for action. The parasympathetic nervous system is part of the autonomic nervous system. Sometimes called the rest and digest system or feed and breed. The parasympathetic system conserves energy as it slows the heart rate, increases intestinal and gland activity, and relaxes sphincter muscles in the gastrointestinal tract.
After high stress situations ie: For example, the increase in heart rate that comes along with a sympathetic reaction will result in an abnormally slow heart rate during a parasympathetic reaction. Sympathetic nerves originate inside the vertebral column, toward the middle of the spinal cord in the intermediolateral cell column or lateral horn , beginning at the first thoracic segment of the spinal cord and extending into the second or third lumbar segments. Because its cells begin in the thoracic and lumbar regions of the spinal cord, the SNS is said to have a thoracolumbar outflow.
Axons of these nerves leave the spinal cord in the ventral branches rami of the spinal nerves, and then separate out as 'white rami' so called from the shiny white sheaths of myelin around each axon which connect to two chain ganglia extending alongside the vertebral column on the left and right.
These elongated ganglia are also known as paravertebral ganglia or sympathetic trunks. In these hubs, connections synapses are made which then distribute the nerves to major organs, glands, and other parts of the body.
