6 Neurological Conditions

6 Neurological Conditions and Symptoms You Should Look Out For

people , health and stress concept – unhappy woman suffering from head ache at home

The nervous system is a complex, highly specialized network. From sight to smell and walking to speaking, our nervous system organizes, explains and connects us to the world around us.

When something goes wrong with a part of the nervous system, however, it can cause a neurological disorder. Neurological disorders affect millions of people each year, yet many people may be unaware they have one.

Understanding symptoms of neurological disorders is important, as it can lead you to an appropriate diagnosis and treatment. Here are six common neurological disorders and ways to identify each one.

1. Headaches

Headaches are one of the most common neurological disorders and can affect anyone at any age. While many times a headache shouldn’t be anything too serious to worry about, if your headache comes on suddenly and repeatedly, you should see a doctor, as these could be symptoms of an underlying condition.

“The sudden onset of severe headache as well as headache associated with a fever, light sensitivity and stiff neck are all red flags of something more serious such as intracranial bleeding or meningitis,” Dr. Chrisman said. “If your headaches are happening often and you find yourself taking over-the-counter pain medication frequently, this is also an indication you need medical attention.”

Although headache disorders like tension-type headaches and migraines aren’t life-threatening, dealing with chronic pain can be debilitating. There are many treatment options available today for headache disorders that can help you get back to a more normal life.

2. Epilepsy and Seizures

Epilepsy is a common neurological disorder involving abnormal electrical activity in the brain that makes you more susceptible to having recurrent, unprovoked seizures. “Unprovoked means the seizure cannot be explained by exposure to or withdrawal from drugs or alcohol, as well as not due to other medical issues such as severe electrolyte abnormalities or very high blood sugar,” Dr. Chrisman said.

The tricky part is that if you have one seizure in your life, it doesn’t necessarily mean you have epilepsy. But, if you have two or more, it may be epilepsy. Seizure symptoms can vary depending on where in the brain the seizure is coming from. After experiencing a seizure, it’s important to see your doctor. There are many effective treatments to manage epilepsy that can result in seizure-freedom, usually medication. “In the appropriate patient, treatment may include epilepsy surgery, which involves removing the seizure focus in the brain, and that can be curative,” Dr. Chrisman said.

3. Stroke

Strokes, which affect nearly 800,000 Americans each year, “are one of the most crucial neurological disorders to be aware of due to the severity of potential symptoms and resulting disability that can occur,” Dr. Chrisman cautioned.

A stroke is usually due to a lack of blood flow to the brain, oftentimes caused by a clot or blockage in an artery. Many interventions can be done to stop a stroke these days, but time is brain (not money) in this case. The B.E. F.A.S.T. mnemonic is helpful to remember to recognize the signs of a stroke: B: Balance difficulties; E: Eyesight changes; F: Face weakness; A: Arm weakness; S: Speech; and T: Time. These signs and symptoms don’t always mean someone is having a stroke, but it’s very important to call 911 and get help right away, just to be sure.

Identify your risk factors for stroke and ways to improve them by visiting our Stroke Risk Profiler.

4. ALS: Amyotrophic Lateral Sclerosis

ALS, also known as Lou Gehrig’s disease, is a somewhat rare neuromuscular condition that affects the nerve cells in the brain and spinal cord. Doctors are unsure what exactly causes ALS, but factors that may cause ALS include genetics and environmental factors.

Symptoms include muscle weakness and twitching, tight and stiff muscles, slurred speech, and difficulty breathing and swallowing. Unfortunately, this condition is difficult to diagnose and often requires the evaluation of a neuromuscular neurologist.

“There is usually a delay in diagnosis for this condition of about one year, on average, by the time the patient gets to the neuromuscular specialist and receives the correct diagnosis,” Dr. Chrisman said. “Although there is no cure, there are treatments, and it’s important to start these as early as possible.”

Read: 10 Foods for Brain

5. Alzheimer’s Disease and Dementia

Memory loss is a common complaint, especially in older adults. A certain degree of memory loss is a normal part of aging. For example, walking into a room and forgetting why may be totally normal.

However, there are signs that may indicate something more serious, such as dementia or Alzheimer’s disease. These symptoms may include getting lost, having difficulty managing finances, difficulties with activities of daily living, leaving the stove on, forgetting the names of close family and friends or problems with language. Behavioral changes along with these memory changes could also raise concerns.

Dementia is a slowly progressive condition and should be evaluated by a neurologist. While there is no cure, there are medications and therapies that can help manage symptoms.

6. Parkinson’s Disease

Parkinson’s disease is a progressive nervous system disorder that primarily affects coordination. Generally, it becomes more common as you age, impacting nearly one million Americans. Currently, there is no cure for Parkinson’s disease, but many treatment options are available.

Why do we Yawn

Why do we yawn and why is yawning contagious?

Just imagine: you’re driving down the highway at 2pm in the heat of the day, and you’re really looking forward to getting to your destination soon. You try to stay awake but drowsiness strikes.

As a result you yawn and then sit up straighter in the driver’s seat, perhaps you’re a little restless and act out in hopes of increasing your arousal.

Is this what people yawn for? Yawning is generally triggered by several things, including fatigue, fever, stress, medications and social and psychological reasons. From one person to another the causes are different.

The question of why we yawn raises a surprising amount of controversy over such a trivial matter. We have no evidence to point us to the exact reason why people yawn.

But there are several theories that explain why people yawn. These include increasing alertness, cooling the brain, and evolutionary theory explains that yawning is to remind others in your group that you are too tired to stay alert, and that someone else should take over.

1. Help us wake up

Yawning comes with increasing drowsiness. This is the hypothesis behind why people yawn. Yawning is also associated with increased activity and stretching movements. Increased body movement may help us stay alert when the pressure of drowsiness increases.

 

Also, certain muscles in the ear ( tensor tympani muscle ) are activated during yawning. This triggers a reset of the range of motion and sensitivity of the eardrum and hearing, which increases our ability to monitor the world around us after we may have lost consciousness before yawning.

Yawning is usually accompanied by stretching movements. from shutterstock.com

In addition, opening the eyeball and flushing the lens of the eye may result in increased visual alertness.

Read: Protect Your Mental Health from Social Media

2. Cools the brain

Another theory as to why we yawn is the thermoregulatory hypothesis which suggests that yawning cools the brain. Yawning draws cold air into the mouth, which then cools the blood to the brain.

Proponents of this theory claim the increase in brain temperature occurs before yawning, with the decrease in temperature occurring after yawning.

But the research that gave rise to this theory only shows that excessive yawning occurs when brain and body temperatures are increasing. The research doesn’t say that yawning has a cooling purpose.

People yawned more frequently when experiments created artificial fevers, which showed a correlation between warm body temperature and yawning. But there’s no evidence to suggest that yawning cools the body—only that a warm body temperature triggers yawning.

3. Guard duty

Yawn-like behavior has been observed in almost all vertebrates. These observations suggest that the yawning reflex is ancient. The behavioral hypothesis based on the theory of evolution refers to humans as social animals. When we are vulnerable to attacks from other species, the function of groups is to protect each other.

Watchkeeping is part of the deal within the group, and yawning and stretching are evidence when an individual’s alertness level is dropping. It is important to change activities to prevent negligence and indicate when to change people just in case.

Neuroscience explanation

The yawning reflex involves many structures in the brain.

A study that looked at the brains of people prone to yawning found activity in the ventromedial prefrontal cortex of the brain. This part of the brain is associated with decision-making activities. Damage to this area is also associated with a loss of empathy.

 

If a certain area around the hypothalamus , which is made up of neurons with oxytocin, is stimulated, in rodents this causes them to yawn. Oxytocin is a hormone associated with social bonding and mental health.

Injecting oxytocin into different regions of the brainstem also causes yawning. These include the hippocampus (associated with learning and memory), the ventral tegmental area (associated with the release of dopamine, the happy hormone) and the amygdala (associated with stress and emotions). Blocking the oxytocin receptors here prevents that effect.

Patients with Parkinson’s disease don’t yawn as often as others, which may be related to their low dopamine levels. Dopamine substitutes have been reported to increase yawning frequency .

Your dog may yawn on a long car trip because your dog is stressed. from shutterstock.com

The same is true of cortisol, a hormone that increases stress. Cortisol is known to trigger people to yawn , while removal of the adrenal glands (which produce the hormone cortisol) prevents people from yawning . This suggests that stress levels may play a role in triggering why people yawn, which could be why your dog may yawn so much on long car trips.

So, it seems that yawning is somehow linked to empathy, stress, and the release of dopamine.

Why is yawning contagious?

Chances are you’ve yawned at least once while reading this article. Yawning is a contagious behavior and seeing someone yawn often causes us to yawn too.

But the only theory offered here suggests that a person’s vulnerability to yawning is correlated with a person’s level of empathy.

It’s interesting to note that people on the autism spectrum are less likely to catch yawns than people with high psychopathic tendencies . And dogs, which are considered to be highly empathetic animals, can get infected when humans yawn .

 

Overall, neuroscientists have developed ideas that explain the various triggers why people yawn, and we have a very detailed picture of the mechanisms underlying yawning behavior. But the purpose of why people yawn remains elusive.

Back in our road trips, yawning may be a physiological cue when levels of self-awareness compete with intense drowsiness. But the important message here is that sleep may be a good choice and encourage drivers to stop and rest, and that should not be ignored.

10 Foods for Healthy Brain

You are what you eat. While you may not literally transform into the things you eat, your nutritional choices certainly play an important role in your overall health. Not only that, but there are certain foods that can even help to maintain or improve the health of your brain. Eating the right foods to keep your brain healthy can dramatically decrease your risk of developing neurological problems later in life. Here are some of the best foods for your brain:

Blueberries

Blueberries contain a compound that has both anti-inflammatory and antioxidant effects. This means that blueberries can reduce inflammation, which reduces the risk of brain aging and neurodegenerative disease. Furthermore, antioxidants have also been found to aid in communication between brain cells.

hard boiled eggs against a grey wooden background

Eggs

Eggs are rich in B vitamins and a nutrient called choline. B vitamins help to slow cognitive decline and deficiencies in B vitamins have been associated with depression and dementia. The body uses choline to create the neurotransmitters responsible for mood and memory.

Fatty Fish

Fish such as trout, salmon, and sardines contain large amounts of omega-3 fatty acids. Not only is 60% of your brain composed of fat containing omega 3s, but it is also essential in the production of brain and nerve cells. Deficiencies in omega 3s can cause learning problems and depression.

Fruits

Certain fruits such as oranges, bell peppers, guava, kiwi, tomatoes, and strawberries, contain high amounts of vitamin C. Vitamin C helps prevent brain cells from becoming damaged and supports overall brain health. In fact, a study found that vitamin C can potentially prevent Alzheimer’s.

A variety of leafy greens such as brocolli, brussel sprouts, kale, parsley, lettuce, and spinach

Leafy Greens

Leafy greens such as broccoli, collards, spinach, and kale contain various nutrients such as vitamin K, lutein, folate, and beta carotene. Vitamin K helps with the formation of fat inside brain cells and has been seen to improve memory.

Nuts

Nuts contain healthy fats, antioxidants, and vitamin E, which have been found to be beneficial for both the brain and heart. Walnuts, in particular, also contain omega-3 fatty acids to further improve brain function essayswriting.org/. In fact, nuts have been linked to improved cognition, sharper memory, and slower mental decline.

Pumpkin Seeds

Pumpkin seeds contain antioxidants, as well as zinc, magnesium, copper, and iron. The brain uses zinc for nerve signaling, magnesium for learning and memory, copper for controlling nerve signals, and iron to prevent brain fog.

Tea and Coffee

Both tea and coffee contain caffeine, which boosts brain function and improves alertness, as well as antioxidants. Green tea also contains the amino acid L-theanine which can cross the blood-brain barrier and increase neurotransmitter activity.

Turmeric powder

Turmeric

Turmeric is a dark-yellow spice that is commonly found in curry powder. Not only is it a strong antioxidant and anti-inflammatory substance, but it can pass through the blood-brain barrier to enter the brain directly. Tumeric has been associated with improved memory, less depression, and the growth of new brain cells.

Whole Grains

Whole grains such as bread, pasta, barley, brown rice, oatmeal, and bulgur wheat contain vitamin E, which is used to protect and preserve healthy cells. In protecting these cells, vitamin E preserves brain function and prevents neurodegeneration.

Read: 6 Neurogical Conditions

Sensory Neuron

Sensory neurons, also known as afferent neurons, are neurons in the nervous system, that convert a specific type of stimulus, via their receptors, into action potentials or graded potentials. This process is called sensory transduction. The cell bodies of the sensory neurons are located in the dorsal ganglia of the spinal cord.

The sensory information travels along afferent nerve fibers in a sensory nerve, to the brain via the spinal cord. The stimulus can come from exteroreceptors outside the body, for example those that detect light and sound, or from interoreceptors inside the body, for example those that are responsive to blood pressure or the sense of body position.

Centra nervous syatem

Types and Function

Different types of sensory neurons have different sensory receptors that respond to different kinds of stimuli. There are at least six external and two internal sensory receptors:

  1. External receptors 

External receptors that respond to stimuli from outside the body are called exteroreceptors. Exteroreceptors include olfactory receptors (smell), taste receptorsphotoreceptors (vision), hair cells (hearing), thermoreceptors (temperature), and a number of different mechanoreceptors (stretch, distortion).

Smell

The sensory neurons involved in smell are called olfactory sensory neurons. These neurons contain receptors, called olfactory receptors, that are activated by odor molecules in the air. The molecules in the air are detected by enlarged cilia and microvilli.

These sensory neurons produce action potentials. Their axons form the olfactory nerve, and they synapse directly onto neurons in the cerebral cortex (olfactory bulb). They do not use the same route as other sensory systems, bypassing the brain stem and the thalamus. The neurons in the olfactory bulb that receive direct sensory nerve input, have connections to other parts of the olfactory system and many parts of the limbic system.

Taste

Similarly to olfactory receptorstaste receptors (gustatory receptors) in taste buds interact with chemicals in food to produce an action potential.

Vision

Photoreceptor cells are capable of phototransduction, a process which converts light (electromagnetic radiation) into electrical signals. These signals are refined and controlled by the interactions with other types of neurons in the retina. The five basic classes of neurons within the retina are photoreceptor cellsbipolar cellsganglion cellshorizontal cells, and amacrine cells.

The basic circuitry of the retina incorporates a three-neuron chain consisting of the photoreceptor (either a rod or cone), bipolar cell, and the ganglion cell. The first action potential occurs in the retinal ganglion cell. This pathway is the most direct way for transmitting visual information to the brain. There are three primary types of photoreceptors: Cones are photoreceptors that respond significantly to color. In humans the three different types of cones correspond with a primary response to short wavelength (blue), medium wavelength (green), and long wavelength (yellow/red). Rods are photoreceptors that are very sensitive to the intensity of light, allowing for vision in dim lighting.

The concentrations and ratio of rods to cones is strongly correlated with whether an animal is diurnal or nocturnal. In humans, rods outnumber cones by approximately 20:1, while in nocturnal animals, such as the tawny owl, the ratio is closer to 1000:1.  Retinal ganglion cells are involved in the sympathetic response. Of the ~1.3 million ganglion cells present in the retina, 1-2% are believed to be photosensitive.

Different kinds of neurons. structure of a typical neuron

Problems and decay of sensory neurons associated with vision lead to disorders such as:

  • Macular degeneration – degeneration of the central visual field due to either cellular debris or blood vessels accumulating between the retina and the choroid, thereby disturbing and/or destroying the complex interplay of neurons that are present there.
  • Glaucoma – loss of retinal ganglion cells which causes some loss of vision to blindness.
  • Diabetic retinopathy – poor blood sugar control due to diabetes damages the tiny blood vessels in the retina.

Auditory

The auditory system is responsible for converting pressure waves generated by vibrating air molecules or sound into signals that can be interpreted by the brain.

This mechanoelectrical transduction is mediated with hair cells within the ear. Depending on the movement, the hair cell can either hyperpolarize or depolarize. When the movement is towards the tallest stereocilia, the Na+ cation channels open allowing Na+ to flow into cell and the resulting depolarization causes the Ca++ channels to open, thus releasing its neurotransmitter into the afferent auditory nerve. There are two types of hair cells: inner and outer. The inner hair cells are the sensory receptors .

Problems with sensory neurons associated with the auditory system leads to disorders such as:

  • Auditory processing disorder – Auditory information in the brain is processed in an abnormal way. Patients with auditory processing disorder can usually gain the information normally, but their brain cannot process it properly, leading to hearing disability.
  • Auditory verbal agnosia – Comprehension of speech is lost but hearing, speaking, reading, and writing ability is retained. This is caused by damage to the posterior superior temporal lobes, again not allowing the brain to process auditory input correctly.

Temperature

Thermoreceptors are sensory receptors, which respond to varying [temperature]s. While the mechanisms through which these receptors operate is unclear, recent discoveries have shown that mammals have at least two distinct types of thermoreceptors. The bulboid corpuscle, is a cutaneous receptor a cold-sensitive receptor, that detects cold temperatures. The other type is a warmth-sensitive receptor.

Read; Neuron Fun Fact

Mechanoreceptors

Mechanoreceptors are sensory receptors which respond to mechanical forces, such as pressure or distortion.

Specialized sensory receptor cells called mechanoreceptors often encapsulate afferent fibers to help tune the afferent fibers to the different types of somatic stimulation. Mechanoreceptors also help lower thresholds for action potential generation in afferent fibers and thus make them more likely to fire in the presence of sensory stimulation.

Some types of mechanoreceptors fire action potentials when their membranes are physically stretched.

Proprioceptors are another type of mechanoreceptors which literally means “receptors for self”. These receptors provide spatial information about limbs and other body parts.

Nociceptors are responsible for processing pain and temperature changes. The burning pain and irritation experienced after eating a chili pepper (due to its main ingredient, capsaicin), the cold sensation experienced after ingesting a chemical such as menthol or icillin, as well as the common sensation of pain are all a result of neurons with these receptors.

Problems with mechanoreceptors lead to disorders such as:

  • Neuropathic pain – a severe pain condition resulting from a damaged sensory nerve 
  • Hyperalgesia – an increased sensitivity to pain caused by sensory ion channel, TRPM8, which is typically responds to temperatures between 23 and 26 degrees, and provides the cooling sensation associated with menthol and icillin.
  • Phantom limb syndrome – a sensory system disorder where pain or movement is experienced in a limb that does not exist.2. Internal receptorsInternal receptors that respond to changes inside the body are known as interoceptors.
  • Blood

    The aortic bodies and carotid bodies contain clusters of glomus cells – peripheral chemoreceptors that detect changes in chemical properties in the blood such as oxygen concentration. These receptors are polymodal responding to a number of different stimuli.

    Nociceptors

    Nociceptors respond to potentially damaging stimuli by sending signals to the spinal cord and brain. This process, called nociception, usually causes the perception of pain. They are found in internal organs as well as on the surface of the body to “detect and protect”. Nociceptors detect different kinds of noxious stimuli indicating potential for damage, then initiate neural responses to withdraw from the stimulus.

    • Thermal nociceptors are activated by noxious heat or cold at various temperatures.
    • Mechanical nociceptors respond to excess pressure or mechanical deformation, such as a pinch.
    • Chemical nociceptors respond to a wide variety of chemicals, some of which signal a response. They are involved in the detection of some spices in food, such as the pungent ingredients in Brassica and Allium plants, which target the sensory neural receptor to produce acute pain and subsequent pain hypersensitivity.

    Connection with the central nervous system

    Information coming from the sensory neurons in the head enters the central nervous system (CNS) through cranial nerves. Information from the sensory neurons below the head enters the spinal cord and passes towards the brain through the 31 spinal nerves. The sensory information traveling through the spinal cord follows well-defined pathways. The nervous system codes the differences among the sensations in terms of which cells are active.

Cholinergic Basal Forebrain Neurons

The integrity of cholinergic basal forebrain neurons depends on expression of Nkx2-1  categories:

The transcription factor Nkx2-1 belongs to the homeobox-encoding family of proteins that have essential functions in prenatal brain development. Nkx2-1 is required for the specification of cortical interneurons and several neuronal subtypes of the ventral forebrain. Moreover, this transcription factor is involved in migratory processes by regulating the expression of guidance molecules. Interestingly, Nkx2-1 expression was recently detected in the mouse brain at postnatal stages.

Using two transgenic mouse lines that allow prenatal or postnatal cell type-specific deletion of Nkx2-1, we show that continuous expression of the transcription factor is essential for the maturation and maintenance of cholinergic basal forebrain neurons in mice. Notably, prenatal deletion of Nkx2-1 in GAD67-expressing neurons leads to a nearly complete loss of cholinergic neurons and parvalbumin-containing GABAergic neurons in the basal forebrain.

We also show that postnatal mutation of Nkx2-1 in choline acetyltransferase-expressing cells causes a striking reduction in their number. These degenerative changes are accompanied by partial denervation of their target structures and results in a discrete impairment of spatial memory.

Article by: Lorenza Magno, Oliver Kretz, Bettina Bert, Sara Ersözlü, Johannes Vogt, Heidrun Fink, Shioko Kimura, Angelika Vogt, Hannah Monyer, Robert Nitsch and Thomas Naumann.

Read the full article on Wiley Online Library.