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Phantom Pain: The Feeling Is As Real As It Can Get!

Phantom pain is a sensation that various individuals perceive towards a part of the body or an internal organ that doesn’t exist. This phantom pain occurs usually when people undergo an amputation surgery. In other cases, it can also happen from birth, in those who are born with a birth defect or a congenital disorder. Sometimes, phantom pains can appear as a result of an injury to the spinal cord or avulsion. Avulsion means that a structure of the body becomes disconnected from the body. This can happen due to a surgical procedure or because of trauma when body parts like ears become removed from the body.

Some people may experience phantom pain for just a short amount of time. The pain will leave by itself eventually. On the other hand, other people might suffer for a long time. The pain is intense and extreme and they keep on suffering. If you or anybody you know might be experiencing phantom pain, do let your doctor know. A physician will be able to reduce the symptoms and provide treatment. And the sooner you get treatment for phantom pain, the better.

Phantom Pain

What is Phantom Pain?

What science knows of so far is that the majority of the people who lose a limb as a result of an accident, surgery etc. will experience a phantom limb.

This very realistic perception that the limb is still there happens quite often, apart from that it can still cause pain to those who experience it.

However, what is interesting about the phantom limb pain, is that one doesn’t necessarily need to have had a surgery to experience the effects. Maybe not the full effects and the full experience of what a real phantom pain feels like, but it can definitely come close enough. In order to understand the following example and the phantom pain, we need to say a few words about body proprioception and body ownership.

Phantom pain: Proprioception and body ownership

Body proprioception is the way we perceive each and every single one of our body parts. We know where our body parts are located to a relative degree. We are also able to subconsciously understand how strong we are which helps us with motor skills and movement. Concepts like muscle memory, hand-eye coordination are quite common in the everyday language. Both of them come from this sense of ownership of what each and every single one of us is.

Some scientists even call proprioception as the sixth sense. The other five senses that we know of – touch, hearing, sight, smell, and taste – provide us with the information from the outside world. Because of the five senses, we are able to perceive the world around us as a unified concept. In an everyday life we don’t just experience one thing at a time, however a multi-sensory integration of all. Proprioception, however, comes from the inside. Scientists call it the sixth sense because people are able to sense what is going on inside our bodies. We know the stimuli that start within our bodies, we understand our relative position in space, our range of motion and our equilibrium. We are aware of our limbs and body parts.

When we pass through a crowded area, we turn at the right moment and attempt to make ourselves smaller. We do that due to the fact that we subconsciously know how much space we occupy. We know that if we go straight on we will hit that nice lady on the left. If we move a little bit to the right, however, we will push the man in the hat who is reading his newspaper. We understand all of this because of proprioception.

Now that we understand a little bit more about body ownership and how we perceive ourselves, it’s time to go back to the example.

Phantom pain: Rubber Hand Illusion

As we have established, phantom pain involves vivid sensations in a lost limb. The general public, however, is able to experience similar sensations without losing a limb. Rubber hand illusion has a lot to do with that concept of proprioception and body ownership and you will see the link with the phantom pain in just a bit.

Ehrsson colleagues in their 2004 study explored the ownership that we as people have of our hands. We know that the hands we are looking at are ours. We can move them in every way possible, we can control the fingers, move each hand individually or clap them together. It is fully ours. Could we trick the brain into thinking another hand could be ours too? That’s the basic concept of the rubber hand illusion.

Phantom pain: Body ownership?

The illusion itself is quite ingenious. The participant will have to place both of their hands on the table, one on each side of a screen. The screen blocks the participant from seeing the left hand outside of the screen. A realistic looking rubber hand goes inside the screen. When the participant looks at the table, he or she will see their real right hand on the table and beside it the left rubber hand because their real left hand is on the outside of the screen, invisible to them. After this, the real experiment begins. The researcher will start by slowly stroking the rubber hand and the hidden left hand with a small brush. He does so in similar strokes on both hands, on the same finger and at the same pace.

The subject will see the scientists stroking the rubber hand but also feel the same stroke on their hidden left hand. After this goes on for a few minutes, the subject will start feeling like the rubber hand is part of their own body and he or she feels the strokes on the rubber hand. The scientist usually ends the illusion by hitting the rubber hand with the small hammer. Interestingly enough, the participant will usually flinch or let out a shock sound due to the fact that they truly felt like the rubber hand was their own.

This rubber hand illusion is a very common one among scientists and brings a lot of insight into our own view of body ownership. Do we really know that much about ourselves? How do we create our self-image? And what does it say about people who experience phantom pain?

Phantom pain: a little background

According to the analysis by Weinstein SM, the first mention of the phantom limb pain occurred in the 16th century, by Ambrose Pare who happened to be a military surgeon.

Elan D. Louis and George K. York in mentioned that the term ‘phantom limb pain’ was coined by Weir Mitchell, who also happened to be a surgeon but at a different timeline. In the 19th century, he practiced during a Civil War and managed to give a description of phantom pain in detail.

Phantom Pain types

Phantom pain can appear in a variety of different ways and it’s important to recognize and understand the differences between them. Identifying what it is will surely help with faster diagnosis and an easier and faster approach to treatment. The differences might come from the variation in sensations that a person might feel.

  • Movement perception where the limb used to be
  • Noticing the weight of the phantom limb
  • Feeling the length of the phantom limb.
  • Feeling different senses where the phantom limb is situated – itchiness, touch, pressure.

As you can see, there are no clear cut differences between types of phantom limbs. Those who suffer from it may experience a variety of things. Sensations help us differentiate between the different types of phantom pain.

Phantom pain: Signs and Symptoms

Phantom Pain

There is a variety of symptoms that can pop up as a result of phantom pain. As mentioned before, the majority of the people will experience some symptoms if they have an amputation surgery. The sensations that can occur during the phantom limb experience include but are not limited to:

  • Warmth
  • Coldness
  • Tingling
  • Itchiness

These sensations are phantom limb sensations and are quite common after an operation. Phantom pain is a bit more severe. Just feeling pain from where the amputation occurred is not a symptom of phantom pain.

When the pain feels like it comes from a part of the body that doesn’t exist anymore, that’s what we call phantom pain. Few things can signify the appearance of phantom pain:

  • It can be prolonged or it can show up and leave at any moment.
  • It happens very shortly after the amputation occurs.
  • People describe the pain as pulsating and vibrating and burning.
  • People feel the phantom limb being put at an angle that bothers them and a position that brings discomfort.
  • The phantom pain usually happens in the part of the body that seems to be the most remote one from the body. Common examples include a leg or a foot
  • The phantom pain can be the cause of stress
  • The phantom pain can start as a result of pressure upon the limb that is left-over after the surgery.

Phantom pain: Causes and Risk Factors

As we mentioned before, the main risk factor for phantom pain still is surgery that results in amputation. The origin of the sensation of phantom pain, however, still remains a mystery. We do not know where it comes from, however, scientists speculate the involvement of certain brain regions and the spinal cord specifically.

Phantom pain: Causes

Different studies have used a variety of neuroimaging methods in order to see the activity that happens during a phantom pain sensation. They were able to discover certain brain areas of interest. A bit of a disturbance between brain connections in the brain might be the reason for the origin of a phantom brain. The signals can become mixed up together due to a sudden loss of a body part and the loss of input from that area. A lot of scientists put it down toward neuroplasticity that has gone wrong. Due to the fact that the brain and the spinal cord stop receiving input from a certain area, the brain tries to compensate and realize what happens and triggers a pain sensation in the lost limb.

Of course, we cannot forget about certain physiological factors like scar tissue, memory of the pain before the amputation and the damage done to nerve endings in the affected area.

Phantom pain: Risk factors

Apart from the obvious amputation surgery, there are a few other risk factors that can play a role in developing phantom pain. Doctors during the surgery should be aware of these risk factors and attempt to minimize the potential for developing phantom pain.

  • Stump pain: a lot of stump pain can contribute to the development of phantom pain due to the damage to the nerve endings.
  • Bad prosthetics: your doctor needs to show you the correct way to utilize the prosthetics. He needs to make sure it fits you and you know all the little details about it.
  • Painful sensations before the surgery: people are more likely to develop phantom pain if they experience pain in the limb beforehand; remembering that pain can contribute significantly to it.

Phantom pain and the Nervous system

In order to understand phantom pain, understanding of the nervous system is important. Many scientists believe that neuroplasticity plays a big role in the development of phantom pain.

Neuroplasticity is quite a famous concept nowadays and a lot of research goes into it. It talks about how the brain is able to form new connections between neurons over the course of a lifetime. Neuroplasticity seems to be responsible for the compensatory effect of diseases and injuries. It allows the brain to re-adjust the functions and certain stimuli responses that come from the outside. Wall and his colleagues explored the notion of neuroplasticity in their 1977 study. They found that the receptive field of certain neurons changes after partial cut off from the nerve supply. Many other studies show the reorganization of the somatosensory cortex following denervation or some sort of damage. That’s why many scientists believe in neuroplasticity as one of the major contributors to the formation of phantom pain.

Neuroplasticity is supposed to lead to benefits and good reorganization in the brain. Many scientists believe that in phantom pain specifically neuroplasticity becomes maladaptive.

Other scientists disagree with the neuroplasticity view. Makin and colleagues in their 2013 study say that plasticity as a result of phantom pain and not the other way around. They looked at different individuals with amputations who have phantom pain. They found that these people actually have very strong cortical representations of the lost limb. Furthermore, they could not find re-organization of cortical representations. In fact, they found that the differences between the brains of amputees and those of non-amputees do not differ and showed similar brain activity. Of course, the sensorimotor cortex played a big role and Makin and colleagues mention it. They say that certain disconnection showed up between the parts responsible for touch and movement processing and some sensorimotor cortex parts and it linked to phantom pain.

Phantom pain: Peripheral Nervous System

Various studies mention the role of the peripheral nervous system in the formation of phantom pain. The nerve endings are disconnected during an amputation surgery. Because of this, neurons become injured and the input to the spinal cord doesn’t work properly anymore. Certain changes happen in the spinal cord. The disconnected nerves cause certain hyper-excitability and this could potentially cause phantom pain.

Phantom pain treatment

There is a variety of different therapeutic techniques that can decrease the symptoms of phantom pain and help cure it. Certain pharmacotherapy approaches should be looked at.

First of all, analgesia and anesthetics should be used before the surgery.  This could prevent the phantom pain from appearing in the first place. It could also decrease the symptoms due to the patient remembering the pain.

Here are some of the most common drugs used for the treatment of phantom pain. Make sure to consult with your physician before taking any medication!

  • Anti-inflammatory drugs: some of the most common medications for phantom pain. These drugs are involved in various brain pathways (e.g. serotonin)
  • Opioids: these drugs are able to bind with central and peripheral postsynaptic opioid receptors and they are able to provide pain relief. Can also help with the side effects of neuroplasticity that are believed to play a role in phantom pain.
  • Tricyclic antidepressants: these drugs can cause pain relief due to the fact that they affect hormones that send out pain signals.
  • Anticonvulsants: these drugs are used for seizures but they can help with nerve damage and pain.

Non-pharmacologically, patients may undergo mirror therapy proposed by Ramachandran and Rogers-Ramachandran in their 1996 study. In this technique patients will attempt to restore the proper visual and proprioceptive disengagement that happens in the brain. Surgical intervention may be needed if all other therapeutic strategies fail.

Phantom Pain: Life style and caring

It can be quite difficult living with constant pain in the lost limb. There are certain steps you can take if you or a loved one are experiencing the symptoms. These steps might be able to reduce the symptoms or at least distract you enough until you get proper treatment.

  • Support: it is very crucial to provide support for somebody who is experiencing phantom pain. Treat as if it’s real pain because to them it is very real.
  • Relax: engage in activities that can help you beat the stress and reduce muscle tension. Activities that make you happy.
  • Don’t be afraid to ask for help. Other people might be a valuable asset in distracting you from problems.
  • Do not forget your medication
  • Exercise: engage in physical activities like walking, cycling, dancing, swimming – whatever you enjoy.
  • Distract yourself: yet again, engage in activities that you love and that make you happy
  • Take care of the stump: follow your doctor’s instructions in order to let the stump properly heal.

Hope you enjoyed this article, please feel free to leave a comment below!

What Is Brain Freeze: Why we get it and ways to avoid it

Summer is finally here. It’s time for ice-cream! YAYYYY!!!! Woops I got carried away and ate mine too quickly. Now I have a brain freeze! Hold on, why is my brain suddenly in pain if there are no pain receptors in the brain itself? Keep reading to find out what is brain freeze, why does it happen and how can we avoid it?

Brain Freeze

What is Brain Freeze?

Brain freeze, also commonly known as ice cream headache, is commonly experienced during the summer. However, it doesn’t have to be. A brain freeze, in simple terms, is a sudden onset of an extremely intense headache that also ends very quickly. Brain freezes are often associated with the consumption of cold foods and drinks, such as ice cream, iced coffee, and so much more. There are plenty of reasons why people get brain freeze, but there are also plenty of ways to stop it once it’s happening as well as strategies to avoid it for the future!

What Causes Brain Freeze?

Ice-cream headaches are caused by cold material moving across the warm upper palate (roof of the mouth) and the back of your throat, such as when you eat a popsicle quickly or gulp your milkshake. It normally happens when the weather is very hot, and the individual consumers something too fast.

Scientists are still unsure about the exact mechanism that causes this pain. Research conducted by Dr. Jorge Serrador, at Harvard Medical School, explained that until now, scientists have not been able to fully understand what causes brain freeze.

“The brain is one of the relatively important organs in the body, and it needs to be working all the time. It’s fairly sensitive to temperature, so [expanding arteries] might be moving warm blood inside tissue to make sure the brain stays warm” -Jorge Serrador

The team of researchers recruited 13 healthy adult volunteers. They were asked to sip ice-cold water through a straw so that the liquid would hit their upper palate. Blood flow in their brain was monitored using a Transcranial Doppler test. They found that that the pain associated with ice-cream headaches were brought on by a rapid increase in blood flow through a major blood vessel into the brain – the anterior cerebral artery. As soon as the artery constricted, the brain-freeze pain sensation wore off.

The brain itself does not feel pain because there are no pain receptors located in the brain tissue itself. This is why neurosurgeons can operate on brain tissue without causing a patient discomfort, and, in some cases can even perform surgery while the patient is awake. The pain associated with brain freeze is sensed by receptors in the outer covering of the brain called the meninges, where the two arteries meet.

Brain freeze can affect anyone. But previous studies revealed that you may be more susceptible to ice-cream headaches or have more-severe ice-cream headaches if you’re prone to migraines. Because of this, neuroscientists think the migraines and ice-cream headaches might share some kind of common mechanism or cause, so they decided to use brain freeze to study migraines.

Headaches like migraines are difficult to study because they are unpredictable. Researchers are not able to monitor a whole one from start to finish in the lab. They can give drugs to induce migraines, but those can also have side effects that interfere with the results. Brain freeze can quickly and easily be used to start a headache in the lab, and it also ends
quickly, which makes monitoring the entire event easy.

Analyzing brain freeze may seem like silly science to some, but it’s actually very helpful in understanding other types of headaches. Here is a video summary on what causes brain freeze.

How do we get brain freeze?

1.Consuming something cold in a warm climate.

Our bodies go through homeostasis, the mechanism to return a body back to its comfortable condition, often. Brain freeze is another form of homeostasis. Our bodies don’t like an extreme change in temperature, ever. In addition to being in a warm environment, our bodies internal homeostatic temperature rests around 98.6. Meaning, you can experience brain freeze in both warm and cool climates. So, when we eat something very cold, our brains and our bodies go into a form of shock, and brain freeze is the immediate response that happens as a means to tell you to stop eating whatever you’re eating.

2.Having something cold touch the top of your palate.

As explained before, our brains can’t actually feel pain. What can feel pain, however, are our cranial nerves or nerves in general. It is believed that there are nerves connected to the roofs of our mouths that when cold touches them, the natural nerve response is the swelling and shrinking of blood vessels. As you could imagine, when something swells and shrinks this can cause a form of pain that mimics the pain that people feel when they have a throbbing headache.

3.Genetics

You may be reading this article and thinking, “I’ve never experienced brain freeze even though I’ve done these things”. As it turns out, that is actually normal! There seems to be a huge genetic predisposition for people to get brain freezes if they are predisposed to getting migraines as well. If you get brain freezes and ask your parents if they do as well, it is very likely that both of your parents will tell you that they experience brain freezes as well. Unfortunately, there is no way to help with this factor, but there are ways to stop your brain freezes when they do occur!

How do you to stop a brain freeze once it has commenced?

1.Raise your tongue to the top of your mouth.

Unsurprisingly, since a brain freeze often occurs because your palate is too cold, pressing your tongue to the top of your mouth will heat it up, alleviating brain freeze faster than if you did nothing.

2.Put your thumb on the top of your mouth.

Shocking! This is the exact same reason that one would suggest for you to put your tongue on the top of your mouth. However, sometimes you’re when eating something cold your tongue can also get cold, thus making it harder to warm the top of your mouth. Your finger is most likely warmer than the inside of your mouth and will help instantaneously!

3.Tilt your head back for at least 10 seconds.

This trick does not consistently work for everyone, but for some people, it’s a great strategy! A change in your blood flow around your brain area can often help with the fast alleviation of discomfort. This strategy is less embarrassing to do in public so you may want to see if this is a good strategy for you!

4.Cover your mouth and nose with your hands and breathe quickly.

This will create a somewhat instantaneous warm environment for you to breathe into and it will warm the top of your mouth extremely fast. Sort of like when you’re in snow and your natural reaction is to cover your mouth with your hands. This trick will work for a brain freeze as well!

5.Spit out whatever you’re eating or drinking.

This one definitely doesn’t need an explanation, but getting rid of the problem will, obviously, get rid of the problem!

6.Take a short walk.

If you take a short walk (or a long walk, if you’re in for it!) you will catalyze blood flow all around your body. This will additionally send some added blood flow to your brain, which will alleviate the discomfort that you are feeling as a result of brain freeze. Don’t stay seated, perhaps do some jumping jacks! Any form of movement will actually help and speed up the recovery time.

7.Drink a drink that’s warmer than your cold food or drink.

Just like your brain didn’t appreciate you quickly changing your temperature by eating or drinking an extremely cold food or drink, it won’t love it if you drink a piping hot drink either. So, drink a room temperature drink to will help warm up the top of your palate but not make your body go into shock.

8.Give yourself a massage in the area that hurts.

Not everyone experiences brain freeze in the exact same areas. So, depending on where you’re feeling pain, if you rub or put pressure on that area, it will actually release some of the tension in that area. It’s sort of like when you rub a sore muscle. This in fact also works for headaches!

9.Waiting.

Okay, this may not be the most helpful tip. However, just as a brain freeze is a sudden onset of the discomfort you experience, it also goes away relatively quickly. So, if you just suck it up for a little bit, it will go away before you know it. Maybe distract yourself in the meantime so you’re not completely focusing on it. Other than that, do the other suggestions mentioned above!

Brain Freeze

How to prevent a brain freeze in the future?

1.Eat/drink slower!

It is often the speed in which you are drinking or eating that causes your brain freeze, not only the temperature of what you’re drinking. The slower you drink, the less shock you’re giving to your palate and the more likely that you can just experience the typical experience of consuming something cold.

2.Don’t drink cold drinks through a straw.

Straws make people drink must faster than if they’re drinking from a cup. So, for the same reason that you’re supposed to drink slower, try to not use a straw to help yourself slow down in the consumption of your drink.

3.But if you are going to drink through a straw, aim the straw to the side of your mouth.

This is another strategy for you to miss your palate when you’re eating. Anything that you can do to consume something without touching your palate is going to make it that much more likely that you won’t experience brain freeze.

4.Eat cold items without touching the food to your palate.

This is extremely logical as the cause of brain freeze is from the cold touching your palate. So, if you can figure out a strategy to eat or drink and miss your palate, you’re going to be good to go! Enjoy your meal without worrying about the uncomfortable effects of brain freeze.

5.Take smaller sips or bites.

If you haven’t realized by now, the common theme here is eating or drinking your cold item less quickly. So, by taking smaller sips or bites, you will make it more likely that you won’t eat or drink as quickly as you would’ve otherwise.

6.Stand by a refrigerator or something else that’s cold before eating or drinking.

As it was mentioned earlier, people are more likely to experience a brain freeze when they are in a warm climate. So, if your body is as cold as the drink you’re drinking, you’re a little less likely to get the brain freeze that you would on a beach. Although this is not always the most practical solution, it is another one!

7.Keep your drink in the front of your mouth for a while before you swallow.

As weird as this sounds, this will actually warm up your drink and not hit your palate when it’s at its coldest temperature. If you really want to enjoy the flavor of your cold drink but can’t endure the pain you get from brain freeze, this is a perfect preventative measure for you!

All in all, the biggest takeaway is that brain freeze is an extremely unpleasant and painful sensation for those of us who experience it. Luckily, even without these strategies, brain freeze doesn’t often last more than a minute. But, using a different plan of action to avoid brain freeze will help extremely. Especially since those of us that experience brain freeze, myself included, also experience migraines. Although migraines are much worse and there’s medication to help with that issue, there is no reason for anyone to experience brain freeze! Our bodies are extremely smart and evolutionarily adaptive for having brain freeze, but every logical person knows they shouldn’t be drinking something that is really cold too fast. Check out more things that can be migraine triggers.

So, just think about the pain you will inevitably experience when drinking a cold drink and use these tactics to make your life less difficult! Now that you’ve got the best tips, you’re ready for the summer. Enjoy! Feel free to leave a comment below.

References

Blatt MM, Falvo M, Jasien J, et al. Cerebral vascular blood flow changes duringbrain freeze‘ FASEB Journal. 2012;26:685.4

Fight or Flight: All You Need to Know About This Response

Fight or Flight. The sympathetic nervous system is one of two subdivisions of the autonomic nervous system, which is part of the peripheral nervous system. All of these subdivisions may seem confusing, but all you need to know about the sympathetic nervous system starts with the peripheral nervous system.

Fight or Flight

CNS vs. PNS

For starters, the nervous system has two main divisions consisting of the central nervous system (CNS) and the peripheral nervous system (PNS). The central nervous system is arguably easy to wrap your head around because it consists of just the brain and the spinal cord. The peripheral nervous system is comprised of everything other than the brain and spinal cord.

Due to how vague the definition of the PNS is, it has to be broken down into multiple different subsets. The two main divisions of the PNS are the somatic and autonomic nervous systems.

The somatic nervous system is also considered the voluntary nervous system because it allows us to interact with our external environment. This is done through voluntary movement of skeletal muscles and our senses.

The autonomic nervous system regulates our internal environment or controls the body functions that we do not have conscious control over. This is a rather complex task as well, so the autonomic nervous system has two subdivisions known as the sympathetic nervous system and the parasympathetic nervous system.

The sympathetic nervous system controls our “fight or flight” response to a dangerous event, but it is also active at a baseline level in order to maintain our body’s homeostasis. The parasympathetic nervous system is the complimentary partner to the sympathetic nervous system. After experiencing a “fight or flight” response, the parasympathetic nervous system takes over in a “rest and digest” response. This allows the body to return to rest.

Fight or Flight: Functions

Fight or Flight

Now that we have a handle on where the sympathetic nervous system lies within the complex wiring of the complete nervous system, we can look at its specific functions.

Traditionally, we experience fight of flight when presented with harmful or life-threatening situations. Our body reacts in ways that can either help up flee the situation, or power through and fight the situation.

The fight or flight response is the primary process of the sympathetic nervous system. It allows us to handle stressful situations by suppressing non-vital bodily functions and enhancing survival functions. During a fight or flight response digestion is slowed or halted. This allows for the energy and resources normally used in digestion to be repurposed to increasing heart rate, getting more oxygen-rich blood to muscles, or dilating pupils.

Our bodies are able to make this response through two pathways. One pathway uses neurotransmitters, and other pathway uses hormones. The difference between a neurotransmitter and a hormone is a bit tricky to understand, especially when talking about the sympathetic nervous system. This is because the same chemical can be a neurotransmitter and a hormone.

What are the types of neurotransmitters

How is this possible? Well, a neurotransmitter is any chemical that is released from a neuron and travels across a synapse. A hormone is a chemical that is secreted from a gland.

Physiology of Fight or Flight

How does the sympathetic nervous system really impact your body? How do these messages get sent to the various parts of your body?

The First Basic Response Pathway

A two-neuron chain of signaling is required for almost every message that the autonomic nervous system relays. The first pathway is made up of the following: a preganglionic cell, a ganglion, a postganglionic axon, and an effector organ.

A preganglionic cell is a neuron that is rooted in the spinal cord. Its axon synapses onto a ganglion, which just a term for a cluster of neurons located in the PNS. From there the axon of the ganglion, referred to as the postganglionic axon, synapses onto the effector organ. An effector organ is any organ that can respond to stimulus from a nerve.

More on synapses 

What neurotransmitters are used in this pathway? The preganglionic axon releases acetylcholine, which binds to acetylcholine receptors on the ganglion. The postganglionic axon then releases norepinephrine onto the effector organ. The effector organ is then either stimulated or inhibited based on the receptors present. The receptors are what determine the action of the neurotransmitter.

The Second Basic Response Pathway

This pathway is referred to as the sympathoadrenal response. This pathway is made up of a preganglionic cell, the adrenal gland, blood vessels, and effector organs.

The preganglionic cell functions the same way as a preganglionic cell in the first response pathway functions. It is rooted in the spinal cord and has an axon that synapses, and releases acetylcholine, onto the next part of the pathway. However, in the sympathoadrenal response, the next part of the pathway is the adrenal gland.

The adrenal gland is made up of the adrenal medulla and the adrenal cortex. When acetylcholine is bound to receptors in the adrenal medulla, it signals hormones to be released into the bloodstream. These hormones are norepinephrine and epinephrine. These two hormones are also found in other parts of the body as neurotransmitters. Norepinephrine is even used as a neurotransmitter in the first pathway. However, as stated previously, the same chemical can be both a neurotransmitter and a hormone. It just depends on where it was released from!

When epinephrine and norepinephrine are released into the bloodstream, they have a wide spreading and fast impact on the effector organs. Just like the first pathway, the effector organ can either be stimulated or inhibited based on the receptors present.

Fight or Flight and Anxiety

Sympathetic Nervous System

In many cases, our bodies have not quite caught up with modern day events. The stress our ancestors experienced running away from predators is much different from the stress you feel before an exam. However, our bodies have a hard time differentiating types of stress.

These stresses that we face today are predominately psychological and unfortunately longer lasting than running from a predator. The danger with perceiving a modern situation as threatening and then subsequently activating your fight or flight response is that the response will be active as long as you feel threatened.

Anxiety has been linked to both the inappropriate triggering of the fight or flight response, as well as the length of time spent in the response state. Panic attack symptoms are very similar to the physiological changes that occur during fight or flight, and while the panic attack will eventually subside, this does not completely stop the fight or flight response.

You can still feel the emotional impact that an unwarranted fight or flight response has on you after the response has subsided. This can include worry and a heightened sense of danger. Unfortunately, this can have not only a psychological toll but a physiological toll as well.

The sympathetic nervous system is so good at redistributing energy to vital survival functions, but if this response stays on for too long, or is continually being stimulated, some health problems may arise.

Digestive problems can occur because the gastrointestinal tract is not getting enough oxygen-rich blood to do its job. Similar types of problems can arise with other parts of the body that are not getting enough blood flow.

It is important to engage in stress relieving activities, as well as relaxing in order to help your parasympathetic nervous system “rest and digest” to counteract “fight or flight”.

Female Brains: Are they as different from male brains?

Everyone seems to know that males and females think and act differently. There is a lot of debate about how much the actual structures of the brain differ between the sexes, but there is no denying that humans have been wondering why and how the male and female brains differ. But, while some brain features are more common in one sex than the other, some are typically found in both, most people have a unique mix. So the answer to how male and female brains differ is more complicated than it seems at first.

How different can male and female brains be?

Female brains-The Human Brain

The human brain is the central organ of the human central nervous system. The central nervous system, or CNS, is made up of the brain and the spinal cord. It receives input from the sensory organs and sends output to the muscles. The human brain has the same basic structure as other brains in mammals but is larger in relation to body size than any other brains. The brain is made up of many specialized brain areas that work together:

  • The cerebral cortex – the outermost layer of brain cells. Thinking and voluntary movements begin in the cortex. The cerebral cortex also plays a key role in memory, attention, perception, awareness, language, and consciousness.
  • The brain stem – connects the spinal cord and the rest of the brain. The brain stem controls basic functions like breathing and sleeping.
  • The basal ganglia – a cluster of structures in the center of the brain. The basal ganglia coordinate messages between multiple other brain areas. The basal ganglia also control voluntary motor movements, procedural learning, routine behaviors or “habits” such as teeth grinding, eye movements, and some parts of cognition and emotion.
  • The cerebellum is at the base and the back of the brain. The cerebellum is responsible for coordination and balance.

The brain is also divided into several lobes:

  • The frontal lobe, obviously located in the front of the brain, is responsible for problem-solving, judgment, and motor function.The frontal lobe also handles and integrates emotional memories with input from the limbic system.
  • The parietal lobe is located above the occipital lobe and behind the frontal lobe. The parietal lobe can actually be divided further into two regions, which control different functions. One region manages sensation and perception and the other manages integrating sensations, primarily processing information from the visual system. The first region integrates the sensory information it receives and forms a single perception, which is then called cognition, or thoughts. The second region constructs a spatial coordinate system to represent the world around us, and basically, tells us where our body is.
  • The temporal lobe is located below the frontal and parietal lobes and is separated by the lateral fissure. The temporal lobe is involved in processing sensory input, which is then retained as visual memory, language comprehension, and emotion association.
  • The occipital lobe is the smallest lobe and is located in the very back of the brain. The occipital lobe contains the brain’s visual processing system.

Female brains- What’s Different?

It is well known that boys and girls differ in their emotional development throughout childhood and adolescence, but the timing, patterning and neurobiological parallels of the difference of development remain poorly understood. Studies suggest that sex steroid receptors are distributed throughout the brain and influence neurodevelopment. Estrogen, androgen, and progesterone receptors are all found in the hypothalamus, consistent with its central role in the control of the sexual and reproductive function. Areas that also have receptors are the amygdala, hippocampus, and cerebellum. The chemistry differences explain why boys sometimes need different methods of stress release than girls.

In 1989,  the National Institute of Mental Health (NIMH) initiated a large-scale longitudinal study of typical brain development, which to date has acquired data regarding brain development and function from over 1000 children (including twins and siblings) scanned 1-7 times at approximately two-year intervals. This study has provided much of the information we know about the developing brain today. Studies utilizing this data have found that the peak brain size in females occurs around 10.5 years, while the peak occurs around 14.5 years in males.

The other areas most frequently reported as being different are the hippocampus and amygdala, with the larger size or more rapid growth of the hippocampus is typically reported in females, and the amygdala is larger or grows more rapidly in males. The hippocampus controls emotion, memory, and the autonomic nervous system, and the amygdala is responsible for instinctual reactions including fear and aggressive behavior. Because of the larger hippocampus, girls and women tend to input or absorb more sensory and emotive information than males do.

Additionally, the right and left hemispheres of the male and female brains are not set up symmetrically. Females tend to have verbal processing centers on both sides of the brain, while males tend to have verbal processing centers only in the left hemisphere. Girls tend to use more words when discussing or describing all of the details of a specific experience, however, males have more difficulty discussing their feelings, emotions, and senses, especially when having to describe them all together.

Scientists have also noticed that on average, male brains tend to have slightly higher total brain volume than female brains, about 10% more. However, it has not been found to factor into intelligence; in fact, a recent study found no average difference in intelligence, but males were more variable in intelligence than females.

Male brains have been found to utilize nearly seven times more gray matter, while female brains utilize nearly ten times more white matter. The brain’s white matter is the networking grid that connects the brain’s gray matter together. Gray matter makes up the processing centers of the brain. Brain activity has shown different patterns of activation in the presence of equal cognitive performance, which suggests that male and female brains may follow slightly different paths to achieve similar levels of function. This difference between male and female brains is probably why girls tend to transition between tasks more quickly than boys do. Also, in adulthood, females are great multi-taskers, while men excel in highly task-focused projects.

Female brains-Why it’s important

The differences between the male and female brain begin when the brain is just developing. But it’s important to remember that all of the differences are only generalized differences in brain functioning and that all of the differences have advantages and disadvantages. Even though popular culture is abundant with supposed examples of intellectual and behavioral differences between the sexes, only a few are supported scientific research, such as higher aggression in men. Sex differences in the brain may even just depend on your family, and the culture you grew up in. Even if male and female brains start out similarly, the differences over time may come around because boys and girls are treated differently, and have different expectations. Your brain is a muscle and can adapt to almost any situation, but it is important to understand gender differences from a neurological perspective, in order to understand different psychological needs, such as stress release and listening skills.

References:

Jantz, GL. Brain Differences Between Genders. Psychology Today. Accessed April 22, 2017 from https://www.psychologytoday.com/blog/hope-relationships/201402/brain-differences-between-genders

Ritchie, Stuart J., et al. “Beyond a bigger brain: Multivariable structural brain imaging and intelligence.” Intelligence 51 (2015): 47-56.

Crustacean brain may process pain

Crustacean brain may process pain.

Until recently many researchers believed the crustacean nervous system too primitive to process pain. But scientists at Queen’s University in Belfast now think that crustaceans may be more sensitive to pain than previously thought. The researchers used crabs as their test animals. And they found that crabs that experienced an electric shock when they hid under a safe, dark rock would eventually learn to avoid the hiding place. And that avoidance is key: the animals’ ability to remember the unpleasant shock and avoid it is consistent with the ability to feel and remember pain. If the behavior was merely a reflex, the critters would continue to visit the shelter.