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Brain seizures: When The Brain Has Too Much Energy

Brain seizures: Some of us have to deal with them every single day, whilst others can be witnesses of someone having a  brain seizure. Most commonly, people having to experience someone suffering from a brain seizure are overwhelmed when their loved ones jerk uncontrollably and subsequently lose consciousness. Not only are the witnesses clueless about which steps to take, but also the patients if his/her seizure occurs for the first time. This article will give you a guide on what brain seizures are, their symptoms, treatments and what steps to take in order to increase the quality of life of the patient. 

What are brain seizures?

What are brain seizures?

Brain seizures are changes in the brain’s electrical activity. This change can cause dramatic, noticeable symptoms or it may not cause any symptoms. Patients that experience brain seizures possess abnormal neural activity which is uncontrolled and happens spontaneously.

The brain function, however, is often not abnormal. The involuntary change in neural activity is considered epilepsy, in which the brain seizures are the symptoms. Though, brain seizures can also be induced in a normal brain under a variety of conditions different species, from humans to flies. Brain function is not abnormal but cognitive aspects might be threatened by many brain seizures.

Brain Seizures Types

Generally, we differentiate between three different types of seizures. Usually, they are dependent on the number of brain cells showing abnormal activity. This is crucial in order to select a suitable treatment for the patient, as different medications have to be used for each seizure type.

  1. Generalized onset brain seizures: In this case, there is no identifiable onset meaning a starting point in the brain cannot be determined. The seizure starts and spreads too quickly making a reliable decision about the trigger impossible. For this reason, treatment using surgery to suppress the symptoms is not available.
  2. Focal onset brain seizures: Whereas in generalized onset seizures the location is not known, in this type of brain seizure, doctors are able to determine the starting point of the seizures. Focal brain seizures can start in one area of the brain or in a specific group of cells either in the left or right hemisphere. Furthermore, patients can have full or impaired awareness during their fit.
  3. Unknown onset brain seizures: If the nature of the seizure cannot be determined, they belong to this group. This is mostly at the beginning or if the patient lives alone without witnesses observing the person with the seizure. As more information is obtained, the seizure is later classified as generalized onset brain seizure or focal onset brain seizure.

How is a brain seizure caused?

Aspects of the brain affected by different brain seizure

The emergence of a brain seizure can be down to several reasons, but determining the exact cause has proven to be challenging. At least half of all patients display idiopathic seizures meaning the cause is unknown. Nevertheless, depending on the age of the patient, determining the trigger of a brain seizure can be narrowed down.

Generally, genetics plays a large role whether someone will experience a seizure in their lives or not. Pinpointing the specific genes which are responsible for the symptoms though is a struggle. This diagnosis is mostly very vague as the relationship between the genes in the brain and the nature of seizures is poorly understood.

What is known on the other hand is a prevalence of about 3 out of 10 patients having a change in brain structure which leads to some sort of brain seizure. Mostly this is the case for children born with alterations in brain regions.  For the elderly, incidence such as a stroke is usually the cause of developing recurrent seizures.

When suffering from epilepsy, an imbalance in the brain’s chemistry is frequently observed. This refers to the neurotransmitters being present in the wrong concentrations (too little or too much in the brain). In general, everybody has got two kinds of neurotransmitters with opposing functions: Neurotransmitter of excitatory and inhibitory qualities, with the former increasing the firing rate and the latter reducing the activity of the neurons. The balance of both kinds has to be maintained and if not given, can result in hyperactivity of the neurons causing epilepsy.

The best-studied neurotransmitter is GABA, or gamma-aminobutyric acid, which possesses inhibitory qualities counterbalancing neuronal excitation. GABA’s counterpart glutamate, the principal excitatory neurotransmitter, plays a crucial role in the initiation and spread of brain seizures. This was demonstrated by During and Spencer in 1993 when they tested the concentration of these two neurotransmitters in the hippocampus before and during a seizure. Before seizures, the glutamate concentration in this brain area was found to be higher than in the control group, whereas the concentration of GABA was observed to be lower. During the seizure, GABA concentrations increased in both groups, however in the control group a greater increase was found. Consequently, drugs to treat epilepsy revolve around these two neurotransmitters, by either reducing the concentration of glutamate or by increasing GABA content in the synapses in order to reduce hyperactivity of the neurons.

Brain Seizures Symptoms

Clinicians group the symptoms into two categories, generalized and partial or focal seizures, in order to find out if a patient suffers from epilepsy.
The different types are:

Generalized brain seizures (produced by the whole brain)

  • “Grand Mal”: The most known form where the patient loses consciousness and collapses. The body stiffens and violent jerking begins usually lasting for about 30-60 seconds. Afterwards, the patient goes into deep sleep.
  • Absence: Individuals experiencing an absence seizure stare into space for a few seconds. They are most common in children and a brief loss of consciousness is reported.
  • Myoclonic: These seizures are brief, shock-like jerks or twitches of a muscle or a whole muscle group. This usually does not last for a long time (only about 1-2 seconds) and the person experiencing it retains full consciousness.
  • Clonic: This type of seizures is very similar to the myoclonic seizure with the difference of a more regular and sustained jerking.
  • Tonic: The muscle tone, the muscle’s normal tension at rest, is highly increased leading to tense feelings in arms, legs or body in general. Awareness usually does not change much and the symptoms subside within 20 seconds.
  • Atonic: Atonic seizures are substantially the opposite of tonic seizures. Instead of the muscles becoming stiff, a person experiencing an atonic seizure will feel their muscles going limp. For instance, a person standing might fall to the ground when suffering an atonic seizure. As tonic seizures, they do not last for a long time either.

Partial or Focal brain seizures

Focal brain seizures are known to originate from a specific brain region causing a variety of symptoms depending on the brain area affected. Generally, doctors differentiate between seizures causing a (partial) loss of consciousness and the ones where consciousness is preserved.

Symptoms of focal seizures with impaired awareness (once called complex partial seizures) could be the following:

  • Staring into space
  • Response to the environment is abnormal or impaired
  • Execution of repetitive movements (hand rubbing, chewing, walking in circles, etc…)

Symptoms of focal seizures without loss of consciousness (once called simple partial seizures):

  • Change of emotions
  • Difference in perception
  • Involuntary jerking of a body part
  • Sensory symptoms (eg. tingling, dizziness and flashing lights)

Note: If an individual experiences seizures repeatedly (once a week or even once every single day), their symptoms will most likely remain similar.

Brain seizures: Diagnosis and what to expect when visiting a doctor?

If a person suffers from a brain seizure (or thinks they have suffered one), the first stop will be consulting your general practitioner. Make an appointment and if the seizure was witnessed by someone, ask this person to join.

Depending on the type of seizure, most likely you were unconscious which makes it difficult for you to describe what happened. However, the doctor will ask you a series of questions, also called the medical interview, in which he will ask you about your general health and incidences before, during and after the seizure. Especially for the medical interview, it is advisable to have someone near you answer questions which you might not be able to answer.

The doctor will most likely be able to diagnose a brain seizure based on the answers of the patient. However, to obtain a clearer idea of the clinical picture of the patient, more tests will be necessary.

The primary physician will ask a neurologist to take a look at the inside of the individual’s brain. Every single brain is different and finding the most suitable treatment for a patient is far from straightforward. The following tests are used when attempting to diagnose brain seizures in detail:

  • Blood tests: The most common blood test is the CBC (Complete Blood count) in which the doctor determines important parameters in your blood, e.g the number of red blood cells, white blood cells, hemoglobin, etc. Therefore a blood test serves to determine the appropriate medication for infections, allergies, and other abnormalities are revealed.
  • Metabolic tests: This test assesses the functioning of your organs, more specifically your body’s ability to metabolize. The evaluation is also done via a blood sample and includes an assessment of the content of important molecules in your blood. The sodium, potassium and blood sugar levels are evaluated. Not only will this help determine an electrolyte imbalance, but also reveal any malfunction of the kidney or the liver. The importance of looking at these organs is to find out whether a disease could trigger the brain seizures, which was found to be the case for instance in patients with diabetes. In this case, doctors focus on treating the symptoms of the illness causing the brain seizures (in this case diabetes) rather prescribing drugs targeting the brain seizures directly.
  • An EEG (electroencephalography) test: The term might sound familiar to most of us, but what is this exactly and how can it help doctors make a more accurate diagnosis? An EEG can reveal the electrical activity of the brain and in which regions abnormal/normal activity is present. The specialists can make conclusions if the brain seizures come from a single area or are more widespread looking at the EEG pattern.
  • CT and MRI scan: Computer Tomography (CT) and Magnetic Resonance Imaging (MRI) are two techniques that will look into your brain. The aim here is to find physical abnormalities that cause the seizures. Although for a lot of people suffering from brain seizures the test results will be negative, it is still an important procedure. In cases where brain seizures are very frequent and strong, determining the exact cause is crucial since the possibility to undergo surgery could be an adequate treatment option.

What to do and not to do when faced with a brain seizure?

If we see our loved-ones suffering from a seizure, it would be normal to be frightened and expect the worst. However, most brain seizures are not dangerous and the person regains his/her normal state within a few minutes without permanent damage. Fact is: Once a seizure is going, you cannot simply force the person to stop jerking, however, you can protect the person inflicting damage to his own body.

The DO’S!

  • Make sure other people are not standing too close to the person having a seizure
  • Remove sharp or hard objects from the surroundings
  • Do not stop the movements of your friend
  • Take a look at his/her watch to record the seizure duration
  • To keep the airway clear, put the person on his/her side
  • And most importantly: Keep calm!

The DONT’S!

  • Do not restrain the person as you might injure him or get injured yourself
  • No offering of food or drinks to the sufferer: A sip of water might be a trigger for choking
  • Do not insert anything into his/her mouth! They will not swallow their tongue
  • No CPR (unless the patient is not breathing after the seizure)

Tips to reduce brain seizures

Since the underlying trigger for a brain seizure is often unknown, it is crucial to reduce the odds of a brain seizure to a minimum. Take the following provisions:

  • Reduce stress by getting enough sleep (it is best to adhere to a regular sleeping schedule)
  • Physical activity or yoga may help feeling more relaxed, as well as deep breathing
  • Limit noise sources and make sure the room is well illuminated when watching TV or when playing video games
  • When going for a run you should do it in the park, rather than in high-traffic areas or unpaved trails
  • But most importantly: Stick to your medication your doctor prescribed you unless he/she tells you otherwise!

Have you witnessed a brain seizure or are you suffering from this condition? Please feel free to comment below.

Left Brain, Right Brain: 9 Ways Our Brain Hemispheres Work Together

What are the functions of each brain hemisphere? What does each half of our brains do? Is it true that the left side is the analytic hemisphere and the right side the emotional side of the brain? Is it true that the ‘right brain’ is the creative one and the ‘left brain’ is the logical one? In this article, we will reveal everything you need to know about brain hemispheres.

Brain Hemispheres

We have often been told that the left hemisphere of the brain is the analytic, mathematical, and logical side, the side which is in charge of reasoning. You’ve probably also heard that the right hemisphere of the brain is the emotional, creative side.

In fact, people often use this difference as a way to define personality, referring to people as either left-brained or right-brained. “If you are a creative, sensitive, and passionate person, then you use your right hemisphere more; if you are an analytical, organized, and thoughtful person you use your left hemisphere more.” We hear that all the time, so let’s check some facts to see whether there is any truth to this common saying. 

How the Two Hemispheres Work

How do the brain hemispheres work?

There is still a lot left to discover about brain hemispheres but here are some facts we do know:

  • The brain is composed of two well-differentiated halves called hemispheres. These halves are connected by a structure called the corpus callosum, which facilitates communication between the hemispheres. These two hemispheres are in constant communication, and in most activities, both work equally.
  • Experts suggest that our level of intelligence is directly related to the quality of the connection between hemispheres. The more connected they are, the more intellectual we will be, such is the example of Einstein’s brain.
  • Each hemisphere is responsible for the activity on the opposite side of the body. That is, the right hemisphere will be responsible for the movements of the left side of the body and vice versa. Therefore, an injury to the left brain will have an impact on the right side of the body.
  • The processing of visual and auditory stimuli, spatial manipulation, facial perception and artistic ability is found bilaterally, although they may show some superiority in the right hemisphere.
  • Contrary to what was thought until recently, according to a study, the visual processing of numbers is performed by both hemispheres equally.

What Do The Two Sides of the Brain Do?

The Right Hemisphere of the Brain:

It deals, to a greater extent, with the following functions:

  • The consciousness of oneself.
  • Recognizing our image in a mirror.
  • Facial recognition.
  • Processing the emotional part of language, such as prosody and intonation.
  • Feelings associated with intense romantic love.
  • Managing visual-spatial attention.

The Left Hemisphere of the Brain

The left hemisphere of the brain is responsible for:

  • Understanding and producing language.
  • Mathematical abilities and recalling facts.
  • Processing attractive faces.

In the next video, Ian Mcgilchrist explains why our brain is divided into two hemispheres, and what each one is responsible for.

The Two Hemispheres and Brain Lateralization

Brain lateralization is the idea that some brain functions rely more heavily on one hemisphere than on another. One example of this is when we process language. The left hemisphere is in charge of language processing for the most part, whereas the right hemisphere only processes verbal information in relation to emotion. However, it has recently been discovered that speech is processed in both hemispheres equally, so perhaps language is not as lateralized as we previously thought. 

Likewise, it was believed that a left-handed person’s brain was less lateralized for language development. That is, it was believed that these people would use more of the right brain hemisphere for language, contrary to the general right-handed population. It has been proven that this only happens in 1% of the left-handed population. 

It was even found that the degree of lateralization of some brain functions may vary from individual to individual.

Our brain is lateralized in some of its functions, however, most of these happen in both hemispheres. If a brain region or even a whole hemisphere is damaged or destroyed, other neighboring areas or even the opposite hemisphere may, in some cases, take over the activity typically performed by the damaged region. When brain damage interferes in the connections between one area and another, alternative connections can be developed to bridge the difficulties. This is only possible thanks to the brain’s great ability to adapt, which is called brain plasticity.

Brain Hemispheres: Do we use one more than the other?

A study from the University of Utah, USA, dismantled these myths:

There is no evidence that people use one of the brain hemispheres more than the other. This group of researchers identified brain networks in charge of process lateralized functions (brain functions that are processed more in one hemisphere than another), to see if it was true that some people used more one of the brain hemispheres more than the other.

During the study, the researchers analyzed the brains of 1,000 people and found that no individual was consistently using one hemisphere over another. They concluded that no personality type is related to the greater use of the left or right hemisphere.

Therefore, it is false that some people use one brain hemisphere more than another depending on their personality. Some functions may be specialized in a particular cerebral hemisphere, but the truth is that we use both hemispheres equally. 

Some functions may be specific to a particular brain hemisphere; however, we use both brain hemispheres equally. Even though one hemisphere is specific for a function, it will always work better in continuous communication with the other hemisphere.Scientists can’t even establish that the right hemisphere is our creative brain. Creativity is a very complex process. According to a study, creative thinking does not seem to depend on a single mental process or brain region. Nor is it particularly associated with the right brain, attention, low level of activation, or synchronization with the alpha waves emitted by our brain.

Where Did the Myth of the Right Brain and the Left Brain Come From?

This myth arose from the misinterpretation of Roger Sperry’s experiments on divided brains. Studying the effects of epilepsy, Sperry found that cutting corpus callosum could reduce or eliminate epileptic seizures.

However, these patients also suffered other symptoms after communication channels between the brain hemispheres were severed. For example, many brain-split patients found themselves unable to name objects that were processed on the right side (those in the left visual field) but were able to name those processed on the left side (those in the right field of vision).

From this information, Sperry suggested that language was controlled exclusively by the left side of the brain.

We hoped you liked our article and please feel free to comment below.

This article is originally in Spanish written by Andrea García Cerdán, translated by Alejandra Salazar. 

Hippocampus: the orchestra director in the deepest part of our brain

Hippocampus. Have you ever gone blank and forgotten what you were going to say? Our brain is full of important data and information that we have stored over the years. Sometimes we have so much information that we force our brain to get rid and ignore some data. The part of the brain in charge of such important functions as memory and learning is the hippocampus. Without this brain structure, we would lose the ability to remember and feel the emotions associated with memories. You want to know more? Keep reading!

Hippocampus

What is the Hippocampus?

The hippocampus is named after the anatomist Giulio Cesare Aranzio who in the 16th century observed that this brain structure bears a great resemblance to a seahorse.

The word hippocampus comes from the Greek Hippos (horse) and Kampe (crooked). In his discovery, this part of the brain was related to the sense of smell and he advocated the explanation that the hippocampus’ main function was to process the olfactory stimuli.

This explanation was defended until in 1890 when Vladimir Béjterev demonstrated the actual function of the hippocampus in relation to memory and cognitive processes. It is one of the most important parts of the human brain because it is closely related to memory functioning and emotions. It is a small organ located within the temporal lobe (approximately behind each temple), which communicates with different areas of the cerebral cortex in what is known as the “hippocampus system.” It is a small organ with an elongated and curved shape. Inside our brain, we have two hippocampi, one in each hemisphere (left and right).

The hippocampus is known as the main structure in memory processing.

Where is the Hippocampus?

It is very well located, connected to different regions of the brain. It is located in the middle temporal lobe.

The hippocampus along with other brain structures such as the amygdala and hypothalamus form the limbic system and are responsible for managing the most primitive physiological responses. They belong to the most “ancient, deep and primitive” part of the brain, in a part of the brain known as “archicortex” (the oldest region of the human brain) that appeared millions of years ago in our ancestors to meet their most basic needs.

The blue part is the hippocampus

What does the Hippocampus do?

Among its main functions are the mental processes related to memory consolidation and the learning process. As well as, processes associated with the regulation and production of emotional states and spatial perception. How does the brain learn?

Some research has also linked it to behavioral inhibition, but this information is still in the research phase as it is fairly recent.

Hippocampus and Memory

The hippocampus is primarily related to emotional memory and declarative memory. It allows us to identify faces, to describe different things and to associate the positive or negative feelings that we feel with the memories of the lived events.

It intervenes in forming both episodic and autobiographical memories from the experiences we are living. The brain needs to “make room” to be able to store all the information over the years and for this, it transfers the temporal memories to other areas of the brain where memory storage takes place in the long term.

In this way, older memories take longer to disappear. If the hippocampus were damaged, we would lose the ability to learn and the ability to retain information in memory. In addition to allowing the information to pass into long-term memory, it links the contents of the memory with positive or negative emotions that correspond depending on whether the memories are associated with good or bad experiences.

There are many types of memory: semantic memory, visual memory, working memory, implicit memory, etc. In the case of the hippocampus, it intervenes specifically in declarative memory (it covers our personal experiences and the knowledge we have about the world), managing the contents that can be expressed verbally. The different types of memory are not governed solely by the hippocampus but are formed by other brain regions. It does not take care of all the processes related to memory loss but it covers a good part of them.

Hippocampus and Learning

It allows learning and retention of information since it is one of the few areas of the brain that have neurogenesis throughout life.

That is, it has the ability to generate new neurons and new connections between neurons throughout the life cycle. Learning is acquired gradually after many efforts and this is directly related to it. For new information to be consolidated in our brains, it is vitally important that new connections are formed between neurons. That is why the hippocampus has a fundamental role in learning.

Curiosity: Is it true that the hippocampus of London taxi drivers is bigger or more developed? Why? London taxi drivers must pass a hard memory test where they must memorize a myriad of streets and places to get the license. In the year 2000, Maguire studied London taxi drivers and observed that the posterior hippocampus was greater. He also noted that the size was directly proportional to the time the taxi drivers were working. This is because of the effect of training, learning and experience changes and shapes the brain.

Spatial perception and its relationship with the hippocampus

Another important function in which the hippocampus stands out is the spatial orientation, where it plays a very important role.

Spatial perception helps us to keep our mind and body in a three-dimensional space. It allows us to move and helps us interact with the world around us.

There have been different studies with mice where it is stated that it is an area of vital importance for orientation capacity and spatial memory.

Thanks to its correct functioning, we are capable of performing acts such as guiding us through cities we do not know, etc. However, the data concerning people are much more limited and more research is needed.

What happens when the hippocampus is disturbed?

An injury to the hippocampus can mean problems generating new memories. An brain injury can cause anterograde amnesia, affecting specific memories but leaving intact learning skills or abilities.

Lesions can cause anterograde or retrograde amnesia. Non-declarative memory would remain intact and uninjured. For example, a person with a hippocampal injury may learn to ride a bicycle after the injury, but he would not remember ever seeing a bicycle. That is, a person with the damaged hippocampus can continue to learn skills but not remember the process.

Anterograde amnesia is memory loss that affects events occurring after the injury. Retrograde amnesia, on the other hand, affects the forgetfulness generated before the injury.

At this point, you will wonder why the hippocampus is damaged when there are cases of amnesia. It is simple, this part of the brain acts as a gateway to brain patterns that sporadically retain events until they pass to the frontal lobe. One could say that the hippocampus is key to memory consolidation, transforming short-term memory into long-term memory. If this access door is damaged and you can’t save the information, it won’t be possible to produce longer-term memories. In addition to losing the ability to remember, when injuries or damage to the hippocampus occurs, you may lose the ability to feel the emotions associated with such memories, since you would not be able to relate the memories to the emotions that evoke it.

Why can the Hippocampus be damaged?

Most of the alterations that may occur in the hippocampus are produced as a result of aging and neurodegenerative diseases, stress, stroke, epilepsy, aneurysms, encephalitis, schizophrenia.

Aging and dementias

In aging in general and dementias such as Alzheimer’s disease in particular, the hippocampus is one of the areas that has previously been damaged, impairing the ability to form new memories or the ability to recall more or less recent autobiographical information. Memory problems, in this case, are associated with the death of hippocampal neurons.

Most of us know of someone who has suffered or suffers from some kind of dementia and has experienced memory loss. It is curious how the memories that remain are childhood memories or the oldest memories. You may wonder why this happens if the hippocampus is supposed to be damaged.

Well, although it is severely damaged (whether by dementia or any other type of illness), the most common memories are the oldest and they are also the most relevant to the life of the person. This is because over time these memories have been “becoming independent” of the hippocampus to be part of other structures related to long-term memory.

Hippocampus and stress

This region of the brain is very vulnerable to periods of stress because it inhibits and atrophies the neurons of this structure.

Have you noticed that when we are very stressed and we have a billion things to do sometimes we feel forgetful?

Stress and specifically cortisol (a type of hormone that is released in response to stressful moments) damage our brain structures sometimes causing neuronal death. That is why it is fundamental that we learn to remain calm and manage our emotions to get our hippocampus to remain strong and continue to exercise their functions optimally.

To know more watch the following video.

If you like this super interesting subject about memory, I recommend you watch the movie “Memento”. I’ll leave the trailer here so you can see what it’s about.

If you liked this post, leave your comment below. I will be happy to read it and answer your questions :).

This article is originally in Spanish written by Mairena Vázquez, translated by Alejandra Salazar.

Frontal Lobe: Areas, functions and disorders related to it

The brain is divided into four lobes, differentiated by their location and functions. In this article, we are going to focus on one of the lobes: the frontal lobe. The frontal lobe is the biggest lobe in the brain and the most important lobe for the human species. 

Why is the frontal lobe so relevant? What are its functions? The following article will give you an all-inclusive look on the frontal lobe. 

Frontal lobe

Frontal Lobe: Anatomy and Functions

The Frontal lobe is located at the front of the brain, at the front of each cerebral hemisphere and in front of the parietal lobe. It is considered the most important lobe due to its functions and because it takes up one-third of the total brain. In other species its volume is inferior (chimpanzees 17% and dogs 7%).

The functions of the frontal lobe depend on the area we focus on. It plays a part on movement control as well as in high-level mental functions or behavior and emotional control. The frontal lobe is divided into two main areas: the motor cortex and the prefrontal cortex.

Motor cortex in the frontal lobe

The main function of the motor cortex is to control voluntary movement, including the ones in expressive language, writing, and ocular movement. This cortex is divided into three areas:

Primary Motor Cortex

Sends commands to the neurons in the brain stems and spinal cord. These neurons are in charge of specific voluntary movements. Inside the primary motor cortex, of both hemispheres, there is a representation of the contralateral half of the body. That is, in each hemisphere, there is a representation of the opposite side of the body.This is known as the motor homunculus and it is inverted, therefore the head is represented at the bottom.

Premotor Cortex

This area is in control of the preparation and movement programming. Premotor cortex automates, harmonizes and archives movement programs related to previous experiences. Within the premotor cortex:

  • Supplementary motor area: in charge of controlling postural stability during stance or walking.
  • Ocular field: controls the joint deviation of the gaze when voluntary exploring a field.
Broca’s Area

It’s considered the center for producing speech, writing, and also in language processing and comprehension. It coordinates movements of the mouth, larynx and respiratory organs that control language expression. Injuries can produce different language disorders. 

Prefrontal Cortex of the Front lobe

The prefrontal cortex is located in the front part of the frontal lobe. It is considered the ultimate expression of human brain development. It is responsible for cognition, behavior and emotional activity. Prefrontal cortex receives information from the limbic system (involved in emotional control) and acts as a mediator between cognition and feelings through executive functions. Executive functions are a set of cognitive skills necessary for controlling and self-regulating your behavior. Within the prefrontal cortex, three areas or circuits are important: dorsolateral, anterior and orbital cingulum.

Dorsolateral area of the frontal lobe

It is one of the most recently evolved parts of the human brain. It establishes connections with the other three brain areas and transforms the information into thoughts, decisions, plans, and actions. It is in charge of superior cognitive abilities such as:

  • Attention: Focus, inhibition, and divided attention.
  • Working memory: maintenance and manipulation of the information.
  • Short-term memory: ordering events.
  • Prospective memory: programming upcoming actions.
  • Hypothesis generator: analysis of the possible outcomes.
  • Metacognition: self-analysis of cognitive activity and continuous performance.
  • Problem Resolution: analysis of the situation and development of an action plan.
  • Shifting: the ability to adapt to new situations.
  • Planning: organizing behavior towards a new objective.

General Cognitive Assessment Battery from CogniFit: Study brain function and complete a comprehensive online screening. Precisely evaluate a wide range of abilities and detect cognitive well-being (high-moderate-low). Identify strengths and weaknesses in the areas of memory, concentration/attention, executive functions, planning, and coordination.

Anterior cingulum of the frontal lobe

This area regulates motivational processes. It’s also in charge of perceiving and resolving conflicts as well as regulating sustained attention.

Orbital area of the frontal lobe

This area is in charge of controlling emotion and social conduct. It regulates emotional processing, controls behaviors based on context and detects beneficial or detrimental change.

A neuroscientist explains the frontal lobe and the types of disorders that can happen after an injury.

Frontal Lobe: Disorders related to it

As we have explained, the frontal lobe is involved in different processes (motors, cognitive, emotional and behavioral). This is why disorders due to injuries suffered to this area can vary from concussion symptoms to others more severe.

Motor disorders

Injuries to the primary or premotor cortex can cause difficulties in the velocity, execution and movement coordination, all leading to different types of apraxia. Apraxia is a disorder in which the individual has difficulty with the motor planning to perform tasks or movements when asked, provided that the request or command is understood and he/she is willing to perform the task. A University of Toronto scientist has discovered the brain’s frontal lobe is involved in pain transmission to the spine. If his findings in animals bear out in people, the discovery could lead to a new class of non-addictive painkillers.

  • Ideomotor apraxia: Deficits or difficulty in their ability to plan or complete previously learned motor actions, especially those that need an instrument or prop. They are able to explain how to perform an action but can’t act out a movement.
  • Limb-kinetic apraxia: voluntary movements of extremities are impaired. For example, they can’t use their fingers in a coordinated fashion (waving).
  • Buccofacial or orofacial apraxia: Difficulty carrying out movements of the face, tongue, mouth, cheeks, etc. on demand.

Apart from the apraxias, other disorders can be developed from injuries to the frontal lobe, such as language disorders or aphasias.

  • Transcortical Motor Aphasia: language disorder due to which the person has a lack of verbal fluency (slow speech with reduced content and poorly organized), limited spontaneous language (lack of initiative) and difficulty or incapacity in writing.
  • Broca’s Aphasia: language disorder that generates a lack of verbal fluency, anomia (inability to access the lexicon to evoke words), poor syntactic construction in speech, difficulties in repetition, reading and writing.

Dysexecutive syndrome

It consists of a group of symptoms, cognitive, behavioral and emotional that tend to happen together. However, the symptoms are going to depend on the injured area:

Dorsolateral Area

An injury in this area is usually related to cognitive problems such as:

  1. Inability to solve complex problems: decrease in fluid intelligence (reasoning, adapting and resolving of new situations, etc.).
  2. Cognitive rigidity and perseveration: the person maintains a thought or action despite being invited to change it.
  3. Decreased learning ability: difficulty in acquiring and maintaining new learning.
  4. Temporal memory impairment: deficit in the order things happened
  5. Deficiency in motor programming and changing motor activities: difficulties in the organization of sequences of movements and the time to change an activity.
  6. A decrease in verbal fluidity: impairment in the ability to recall words after an instruction. This action not only requires the lexical part but also organization, planning, focus and selective attention.
  7. Attention Deficit: difficulty maintaining your attention and inhibiting other irrelevant stimuli or changing the focus of attention.
  8. Pseudo-depressive disorders: similar symptoms to depression (sadness, apathy, etc.).
Anterior cingulum area
  1. Reduction of spontaneous activity: appear to be static.
  2. A loss in initiative and motivation: noticeable apathy.
  3. Alexithymia: difficulty identifying emotions and therefore inability in expressing own emotions.
  4. Language restriction: answers tend to be monosyllabic.
  5. Difficulty in controlling interference: selective attention impairment.
  6. Pseudo-depressive disorders. 
Orbital area

The symptoms of an injury in this area are more behavioral. The person’s behavior tends to be uninhibited.

  1. Changes in personality: high instability between who he is and how he acts. Similar to what happened to Phineas Gage. 
  2. Irritability and aggressiveness: exaggerated emotional reactions in daily life situations.
  3. Echopraxia: imitation of observed movements in others.
  4. Disinhibition and impulsivity: lack of self-control over their behavior.
  5. Difficulty adapting to social norms and rules: behaves socially unacceptable.
  6. Judgment is impaired: many reasoning errors.
  7. Lack of empathy: difficulty understanding other people’s feelings.
  8. Euphoria
 The frontal lobe is incredibly important for humans to function to their full potential. Even without brain injury, it’s crucial to maintain our cognitive skills active. CogniFit offers a complete assessment of your cognitive skills and brain training not only as a rehabilitation due to injury, dementia, etc. but it can also strengthen your current neural patterns. Brain health is essential to lead a full life.
Hope you liked this article, feel free to leave a message below!
This article is originally in Spanish written by Natalia Pasquin Mora, translated by Alejandra Salazar. 

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.

Hypothalamus: the importance of hormones in the brain

What is the hypothalamus? Let’s start by painting a picture: Your stomach starts churning. It’s been hours since you last ate and you can feel the hunger intensely. You start craving every food available and it starts to become difficult to concentrate. The only thing you can think about is food and it becomes too uncomfortable to bear so you decide to eat. Does this sound familiar?

If you want to learn in depth about the hypothalamus don’t miss “the extend further” section at the end of this article!

The responsible of this whole process is the hypothalamus, a small sub-cortical structure located in the center of the brain. Being only the size of a pea, the hypothalamus is in charge of regulating different functions that are essential to our day to day life, such as eating and homeostasis. If it weren’t for the hypothalamus, we wouldn’t know when we needed to eat and we would end up dying of hunger.

It modules the food intake by increasing or decreasing hunger and satiation awareness. – Ali Inay on Unsplash

What is the Hypothalamus?

The hypothalamus and the thalamus are part of the diencephalon. They are part of the limbic system and contain the main diversity in neurons of the whole brain. It’s in charge of the autonomic nervous system and the endocrine system. It’s an endocrine gland that releases hormones in charge of modulating behaviors relating to species maintenance. It also regulates hormone secretion of the hypophysis (pituitary gland) with whom it shares the hypothalamic-pituitary-adrenal axis. It’s made of two different secreting neurons: The parvocellular (who secrete peptidic hormones) and the magnocellular (which secrete neurohypophysial hormones).

Where is the Hypothalamus located?

Having a perfect spot in the brain is important. It is located in a brain part just beneath the thalamus (from there the name) and right above the brainstem. It connects with the hypophysis through the pituitary stalk. The hypothalamus central position allows it to communicate perfectly, receiving information from different body structures and sending information to others.

What does the Hypothalamus do? How does it keep us alive?

Its functions are essential to our daily life. It is responsible for maintaining the body’s systems, including body temperature, body weight, sleep, mating, levels of aggression and even emotional regulation. Most of these functions are regulated by a chain of hormones that inhibit or release between themselves.

  • Hunger: when our body detects that we have don’t have enough energy saved, it sends Ghrelin (hunger hormone) to the hypothalamus, telling us we need to eat. It then releases a neuropeptide that produces the hunger feeling in our body. In the painted picture above our body is producing so many neuropeptides that we feel overwhelmed by hunger.
  • Satiation: when we have eaten enough, our body has to tell our brain that we don’t need any more food and that we need to stop eating. While we are eating our body produces insulin which in turn increases the production of a hormone called Leptin. Leptin travels through our blood until it reaches the ventromedial nucleus of the hypothalamus. This inhibits the production of neuropeptides, therefore, stopping the hunger sensation.
  • Thirstiness: Similar to hunger, when the body is thirsty it releases an antidiuretic hormone (vasopressin) that allows for the body not to lose water and stimulate drinking more.
  • Temperature: The blood temperature when it arrives at the hypothalamus will determine if we need to reduce or increment our body temperature. If the temperature is too high, we need to lose heat, therefore, the anterior portion with inhibit the posterior, producing certain events such as sweating, in order to lower heat. On the other hand, when the temperature is too low, the posterior portion will inhibit the anterior. This will enable the release of a thyroid stimulating hormone (TSH) and the adrenocorticotropic hormone (ACTH), both helping heat conservation.
  • Sleep: The reason why it’s so difficult to sleep with the light on is because of the hypothalamus. The sleep cycle is regulated by circadian rhythms, which in turn are managed by a set of neurons in the medial hypothalamus called the suprachiasmatic nucleus. This nucleus receives information from ganglion cells in the retina through the optic nerve tract. This way the retina is capable of detecting a change in lighting and sends the information back to the hypothalamus. The set of neurons process the information and then it is sent to the pineal gland. If there is no light, the pineal gland will secrete melatonin (sleep hormone). If there is light, the gland reduces melatonin levels which promotes wakefulness.
  • Mating and Aggression: Even though these behaviors are opposites they are highly related in the animal world and are also regulated by the hypothalamus. Some neurons are stimulated when there is mating behavior present while others when there is aggression. However, there are other neurons that happen to respond to both scenarios. The amygdala sends in information related to the aggressive area in the hypothalamus so that it can release important and pertinent hormones depending on the situation.
  • Emotions: when we experience an emotion this comes with many physiological changes. For example, when walking in a dark alley by yourself the natural response is to feel fear. Therefore the body has to prepare to respond appropriately given the circumstance. So, the hypothalamus sends information to the different parts of the body (increasing our breathing rate, contraction of the blood vessels, pupil dilation and muscle contraction). This way, the hypothalamus allows us to detect threats and run if necessary away from it. That being so, it enables the physical response to the emotion.

What relationship does the hypothalamus have with love?

One of the most important brain functions is processing emotions. These emotions are processed in the limbic system. The hypothalamus is a big part of this system since it’s in charge of letting the whole body know what emotion the brain is feeling. How emotions work in the brain is a complex task, nevertheless, the hypothalamus is responsible for how we feel love. The hypothalamus produces phenylethylamine, a type of neurotransmitter with similar effects to amphetamines. This is the reason why when we fall in love we feel happy and euphoric. This neurotransmitter also leads to an increase in adrenaline and noradrenaline, which rises the heartbeat, oxygen levels and blood pressure (triggering the sensation of your “heart skipping a beat”).

On the other hand, the brain also produces dopamine and serotonin, which allows us to focus our attention on the person that makes us feel these emotions and regulate our emotions accordingly. Consequently, the hypothalamus is very important since without it, we wouldn’t be able to fall in love.

Without the it, we wouldn’t be capable of falling in love.

What link is there between the hypothalamus and the hypophysis (pituitary gland)?

The hypothalamus regulates the emission of hormones from the hypophysis. The hypophysis is also an endocrine gland and its under the hypothalamus, protected by the sella turcica (bone structure in the base of the cranium). The pituitary gland function is to secrete hormones, under the hypothalamus command, through the blood that our body needs to maintain homeostasis (level our temperature or balance different hormones). Their relationship is so close that they form the hypothalamic-pituitary-adrenal axis and they couldn’t work separately. The hypophysis allows for the hypothalamus to extends its effects to the rest of the body.

What happens when the hypothalamus is disturbed? In what disorders o diseases is the hypothalamus involved?

Given the relevance of the hypothalamus, an injury in any of the hypothalamus’ nuclei can be fatal. For example, if the satiation center is damaged (not being capable of being satiated), we wouldn’t stop eating and therefore eat non-stop with a high risk to what this conveys. Some of the most frequent pathologies are:

  • Diabetes insipidus: It is when the supraoptic, paraventricular and the supraoptic hypophysial fasciculus nuclei are injured. Due to low production of ADH, there is more liquid intake and more urine output.
  • Injury in the caudolateral hypothalamus: If this region is damaged all sympathetic activity of the nervous system will diminish including body temperature.
  • Injury in the medial hypothalamus: all parasympathetic activity of the nervous system will be damaged but the body temperature will rise.
  • Korsakoff Syndrome: with the mammillary nucleus (related to the hippocampus) altered, there will be anterograde amnesia, the person will have difficulty remembering new information in long-term memory. Since remembering is difficult, people with this syndrome tend to use fabrications to fill the gaps. This disorder is usually associated with chronic alcoholism it can also happen as an alteration in the mammillary tubers and their connections.

To extend further…

What hormones are produced in the hypothalamus?

The hypothalamus function is through hormone release. Some of the hormones are:

  • Neurohormones: Antidiuretic hormone and oxytocin.
  • Hypothalamic factors: The hypothalamus uses corticotropin-releasing hormone (CRH or corticoliberin), thyrotropin-releasing hormone (TRH), gonadotropin-releasing hormone (GnRH or gonadoliberin), growth hormone–releasing hormone (GHRH or somatoliberin).

Of what nuclei is the hypothalamus made of and what is their purpose?

Each nuclei has a main purpose:

  • Arcuate nucleus: it’s part of the emotional function of the hypothalamus. Its endocrine function consists of synthesizing hypothalamic peptides and neurotransmitters. In charge of liberating the gonadotropin hormone.
  • Anterior hypothalamic nucleus: it’s in charge of releasing the heat when sweating. It’s also in charge of liberating thyrotropin in the hypophysis.
  • Posterior hypothalamic nucleus: Its function is to keep the heat inside the body when it’s cold.
  • Lateral hypothalamic nucleus: it regulates thirst and hunger. When it detects a lack of sugar or water it tries to find homeostasis.
  • Mammillary nucleus: given its connections with the hippocampus, it’s related to the memory.
  • Paraventricular hypothalamic nucleus: It regulates hormone release from the hypophysis (oxytocin, vasopressin, and corticotropin).
  • Preoptic Nucleus: it influences functions such as nutrition, locomotion, and mating.
  • Supraoptic nucleus: It regulates arterial pressure and liquid equilibrium through the antidiuretic hormone.
  • Suprachiasmatic nucleus: In charge of hormones relating to circadian rhythms.
  • Ventromedial nucleus: its role consists of regulating satiation.

From where does the hypothalamus receive information? Where does it send it?

The hypothalamus has great different connections due to the brain area where it’s located. On one side, it receives information from other structures (afferent) and then sends information to other parts of the brain (efferent).

Afferents

  • Reticular cephalic flexure: From the cephalic flexure to the lateral mammillary nucleus.
  • Median prosencephalic fasciculus: from the olfactory region, septal nuclei and amygdala region to the preoptic lateral and lateral hypothalamus.
  • Stria terminalis: from the hippocampus to the septum and mammillary nucleus.
  • Precommissural fornix fibers: connect with the dorsal hypothalamic area, septal nuclei and preoptic lateral nucleus.
  • Postcommissural fornix fibers: takes the information to the medial mammillary nucleus.
  • Retinohypothalamic fibers: Take information from the amount of light in the retina and sends it to the suprachiasmatic nucleus for circadian rhythm regulation.
  • Cortical projections: receives information from the cerebral cortex and sends it to the hypothalamus.

Efferents

  • Dorsal longitudinal fasciculus: from the medial and periventricular regions of the hypothalamus to the grey matter.
  • Mammillary efferent fibers: From the medial mammillary nucleus to the anterior thalamic nuclei, and also from the mesencephalon to the ventral nuclei.
  • Supraoptic nucleus: from the supraoptic nuclei to the posterior lobe of the hypophysis.
  • Tuberohypophyseal: from the nuclei arcuati to the infundibular stalk.
  • Descendent projections to the brainstem and spinal cord: from the paraventricular nucleus to the solitary nucleus and the ventrolateral regions of the medulla oblongata.
  • Efferent projections to the suprachiasmatic nucleus: it connects directly with the pineal gland.

Questions? Leave a comment below 🙂

This article was originally written in Spanish by David Asensio Benito, translated by Alejandra Salazar.