Tag Archives: Hormones

The comfort zone: What it is and is it beneficial? Tips to break out

The comfort zone. It contributes to making us feel mentally safe in our everyday life. Developing a routine such as arriving to work always at the same time using a fixed mode of transportation or cooking a good meal we have a lot of experience with contribute to reaching a higher productivity in these tasks. However, on the other hand stepping out of this powerful state of comfort has proven to be even more beneficial for the individual. But how can this be when we are constantly told to follow a routine in order to achieve maximum performance? Keep reading to find out.

The comfort zone

What is the comfort zone?

The word “comfort zone” is widely accepted in the English language and appears frequently in everyday life.

It generally describes a “behavioural state within a person operates in an anxiety-neutral condition, using a limited set of behaviours to deliver a steady level of performance, usually without a sense of risk”.

What this suggests is a steady performance if the person does not experience a change in anxiety. If however fluctuations in anxiety and skills are seen, a change in performance, either upwards or downwards, will be observed as a result.
To grow as a person, it is essential to break out of this state of comfort every once in a while by exposing yourself to a change in anxiety. Nevertheless, it is a difficult process stepping out of our comfort zone as at the beginning of this process, the person doing so will experience more anxiety than before.

Why do we feel at ease inside the comfort zone?

A lot of reasons exist why humans are wired to stay within the comfort zone.
Each of us has our own “comfort zone” where we feel at ease. It implies familiarity, safety and security keeping our anxiety and worry at a minimal level. Challenging yourself by stepping outside this zone of comfort would mean increased levels of anxiety and stress triggering a hormonal cascade. Human beings are naturally wired to avoid these changes in anxiety and stress.

Why is it so hard to leave our comfort zone?

  • Stress and Anxiety: Whenever we break out of our comfort zone, a stress response followed by anxiety is triggered. The natural response is to remove the stressor as quickly as possible. The only way to achieve this is mainly returning back to the comfort zone which makes keeping yourself out of your comfort zone extremely challenging.
  • Uncertainty: This will be a natural consequence if someone leaves his or her comfort zone. For the majority, the feeling of uncertainty leads to insecurity and can be perceived as a threat activating a stress response. The more uncertain you are, the higher will be your levels of stress mentally and physiologically.
  • New situations require extra energy: Inside your comfort zone, the person has established a routine allowing him or her to perform the tasks automatically (without a lot of thinking). These processes are run by the basal ganglia (a brain area responsible for executing habit-based behaviour), tasks such as shaving, brushing our teeth or bathing. If we stay within the comfort zone, the associated tasks are run by this area of the brain operating very energy efficient.
    Novel tasks, on the other hand, require the input of the prefrontal cortex (a brain area responsible for logical reasoning) which consumes a lot more energy than the basal ganglia. If the energy is depleted (which happens quickly in the prefrontal cortex), we feel discomfort as the prefrontal cortex is tightly linked to the amygdala (the emotional centre of our brain). According to these points, remaining inside the comfort zone seems highly favourable. It provides a state of mental security leading to regular happiness, low anxiety and reduced stress. However, we are often told to leave this state of comfort. This is achieved by expanding your comfort zone and is highly recommended. In order for this to happen though, we temporarily need to abandon this state of comfort, a task which is not so easily accomplished.

The comfort zone, the optimal performance zone and the danger zone

Before we can talk about leaving the comfort zone, we have to understand the core concepts, mainly the existence of three different zones:

  1. The comfort zone
  2. The optimal performance zone
  3. The danger zone.

We first look at an early experiment conducted with mice in 1907 by Yerkes and Dodson.
The study revealed “anxiety to improve performance until a certain optimum level of arousal has been reached. Beyond that point, performance deteriorates as higher levels of anxiety are attained.”

This suggests an increase in performance when anxiety levels are higher than normal. However, if the person is too anxious, performance will drop again. This relationship can be applied to the three different zones. We find ourselves in the comfort zone when anxiety levels are minimal. Depending on what extent we leave our comfort zone, anxiety levels can increase sharply or only marginally. In the case of a marginal increase of anxiety levels, the person experiencing it will be in the optimal performance zone. This is a state where increased skills are seen and where the elevated anxiety levels can be kept under control.

A real-life example would be an important job interview. If the person is not required to attend the interview, he or she is in the comfort zone and anxiety levels are minimal. However, as soon as the day of the interview has come, anxiety levels rise. When conversing with the manager, the potential employee is not only able to control his/her anxiety levels, but most of the times even possess increased communicative skill. He is now operating in the optimal performance zone.

But what happens in the event where anxiety levels do not increase only by a little, but significantly? The person would leave his or her comfort zone too but would end up in the danger zone in which performance is worse than in the comfort zone. The level of anxiety would simply be too high. Following the example, imagine the same job interview with a person suffering from autism (a disorder in which the affected person finds any social interactions extremely challenging). For this person, anxiety levels will be much higher when he or she is invited to the interview which leads him to perform worse (he skipped the optimal performance zone completely). For this individual, a task which would not have caused the anxiety to rocket would have been more appropriate in order to shift swiftly from the comfort zone to the optimal performance zone.

But why is it beneficial to leave the comfort zone?

A few benefits have become already visible, mainly the increase in performance and the acquisition of new skills when being pushed away from the comfort zone. However, the list of advantages does not stop there.

  • Increase in productivity: Comfort is a productivity killer. If we do not have the sense of uneasiness to complete a given work before a deadline, we tend to postpone and do the minimum work required. This phenomenon is often seen in students procrastinating. If the deadline for an assignment is far, the work they put in tends to be low. However, as soon as the deadline is approaching, they start to increase their productivity drastically as they are now in the optimal performance zone.
  • Radical changes become easier to handle: Some people always wish to stay within their state of comfort, however leaving the comfort zone sometimes just happens out of the blue and there is nothing you can do about it (change of job, move to a different home, change in a relationship, an illness). A person that has already left the comfort zone once or twice will be more able to handle also those life changes and transitions. It is important to be at peace with the unknown to combat the negative effects that change can bring. Leaving the comfort zone on a regular basis can help with exactly this.
  • Expansion of your boundaries in the future: Leaving the comfort zone creates a feeling of anxiety which has to be coped with. The more times you leave your state of comfort, the better you are able to cope with this increase of anxiety. This allows you to become accustomed to this state of optimal anxiety where you perform at your best. Ultimately you are willing to push yourself more when repeatedly exposed to the unknown.

Tips to break out of your comfort zone

  • Become aware what lies inside and outside of your comfort zone!
    What are the things that you want to accomplish but triggers a feeling of anxiety in you? Identifying these is of utmost importance in order to know how to expand your comfort zone. Draw a circle and write everything down you associate with discomfort outside of the circle. Inside the circle, you write down everything that triggers comfort. This process will allow yourself to identify not only your discomforts but also your comforts.
  • Consider failing as something positive!
    It sounds difficult, but try to see failure as your teacher. What did this negative experience teach you? You can use this knowledge to increase your chance of success for the future.
  • Surround yourself with people taking risks!
    If you are willing to improve your skills to leave the comfort zone, stick to people that do exactly that. The influence of them will certainly have an effect on your behaviour.
  • Honesty with yourself!
    We have all been there. A task that we are afraid of is waiting and we say “I don’t have time for this right now!” Most of the times though, you are lying to yourself. Instead be honest and say “I’m afraid to do this!”. Confronting your fears will increase your chances of moving forward more easily.
  • Take it slow!
    Start by taking small steps when moving out of your comfort zone. Try making a plan of goals you want to achieve. Try to not be overambitious in a short period of time or you risk becoming demotivated. It is essential for you, to return to your comfort zone from time to time as explained in the next paragraph.

Move out of your comfort zone. You can only grow if you are willing to feel awkward and uncomfortable when you try something new.

Brian Tracy

Why should we return to our comfort zone from time to time?

Though it is important to break out of your comfort zone, it is equally important to also return to this state of comfort from time to time. It is indeed beneficial to leave the comfort zone, but staying outside for too long and you might end up getting your stress and anxiety levels too high. Ultimately, you have to return to the comfort zone to prevent your anxiety levels from taking over and you end up in the danger zone. Once in this zone, your performance drops sharply and leaving the comfort zone for good becomes even more challenging than before. For this reason, allowing yourself some breaks from time to time is essential.

Pregnancy Changes the Brain: Does Pregnancy Brain Have Negative Effects Long Term?

Pregnancy changes the brain. She took her pregnancy test and it was confirmed, she was going to bring a new life into this world. What an exciting time in a mother’s life when she discovers she is pregnant, the bliss fills the life of her loved ones, and from that day onwards, she lives a life of not only a woman or a wife but also takes up a new role of a mother. It is natural to have mixed feeling when a woman realizes she is pregnant, especially if she is experiencing it for the first time. She has to educate herself on many aspects of the new change, the do’s and the don’ts and, most importantly, the changes her body is going to go through. As science and technology have progressed, the awareness that pregnancy has the ability to alter a woman’s life in terms of the hormonal, physiological and emotional state of the body is much talked about, and everyday new studies are being contributed to the understanding of these changes. But did you know besides the established facts of gaining weight, hormonal changes, change in taste buds, sometimes sore feet and elevated levels of blood pressure and sugar levels, there is a strong connection between pregnancy and the brain? Let’s get educated on how pregnancy changes the brain!

How pregnancy changes the brain

Do you have “pregnancy brain”? Take the test below to find out!

1. How often do you walk into a room meaning to do something, only to forget what you were supposed to do?
  • The surge in hormones directs your attention elsewhere, which may cause you to forget things more often than usual!
2. How often do you forget common, everyday things (Ex. forgetting to put on shoes, forgetting names of family members)?
  • Sleep deprivation combined with all of your hormones can contribute to memory loss. But fear not, brain games can help you bring back some of your usual clarity!
3. How often do you feel overwhelmed?
  • It's completely normal to feel overwhelmed, especially if it's your first child! There's a lot to worry about between preparing for the new baby and caring for your own health. Just remember to take a deep breath every once in a while, and try out the tips below.
4. How often do you feel frustrated about not remembering as much as you used to?
  • It's common to feel frustrated, especially when you don't feel like your normal self. Check out the tips below to learn how you can combat this, and feel more like yourself!

Pregnancy changes the brain-General body changes

The development in a pregnant female’s body is a week by week progression and as they cross each trimester (a period of three months), the changes are more evident and noticeable. What are the changes that occur? Why do these changes happen? Are the changes reversible?

Many scholars and organizations are advocates to answer basic and complex questions that may arise during pregnancy for mothers to be. The Office on Women’s Health, U.S Department of Health and Human services (OWH) is an organization that is dedicated to educating women around U.S towards various female health related topics such as cancer, birth control, pregnancy and much more. According to OWH, the following basic information on stages of pregnancy is significant for women,

  • First Trimester (week 1 to week 12) a female’s body goes through a major hormonal change which further affects each and every organ in their body. Furthermore, the hormonal change is responsible for the tiredness, headaches,  mood swings, and food cravings.
  • Second Trimester( week 13 to week 18) observes changes such as body aches, darkening of the skin around the nipples, itching on the abdomen, sore feet and palms, stretch marks and weight gain. These changes may vary from person to person.
  • Third Trimester (week 20 to week 40), the mother can feel the baby move, but many of the discomforts of the second-trimester increase and as the baby grows, the pressure on the mother’s bladder is increased adding to the uneasiness.

As stated above, the changes mentioned (along with many others) are due to the hormonal changes that take place during pregnancy. Elevated levels of Estrogen and Progesterone (main pregnancy hormones) are primarily responsible for the variations in a female body at the time of pregnancy both externally and internally. This may also indicate how and why pregnancy changes the brain.

Pregnancy changes the brain- Gray Matter

Now that we have a basic idea of how the body changes during pregnancy, let’s try to understand how pregnancy changes the brain.

In a more recent study published in 2017 by, Hoekzema and colleagues “Pregnancy leads to long-lasting changes in human brain structure that focused on the brain change that occurs during pregnancy. The pre and post pregnancy MRI testing of 25 first-time mothers and fathers study highlighted the fact that pregnancy alters the brain structure of the mother substantially. The MRI reports suggested that Gray Matter(GM) volume was reduced in a few areas. However, this reduction was not noticed in fathers and women who did not experience childbirth. Also, the brain changes were noticed 2 years post pregnancy, confirming long lasting effects of how pregnancy changes the brain.

“Loss of volume does not necessarily translate to a loss of function,” said Hoekzema, “Sometimes less is more.”

The study of the brain and how pregnancy changes the brain has been a subject of study for many neuroscientists and other in related fields. Many studies have suggested that the gray matter is responsible for emotions, sensory perception, decision making, cognition, speech, self-control, and memory. Modifications in the gray matter might limit a mother’s social cognition skills but it prepares her with adaptive methods during the motherhood transition. The study also concentrated on the evidence that the depletion in gray matter volume overlaps the part of the brain that is actually responsible for a mother being able to recognize her baby’s needs after the baby is born. In addition, the study also provided us with significant evidence reflecting the association between the quality of mother and infant attachment is predicted due to how pregnancy changes the brain.

Pregnancy changes the brain- Hormones

As you already know, the brain gets flooded with hormones during pregnancy. During the first trimester, it’s common to feel a mix of happiness, anxiety, or even upset after an unplanned pregnancy. These feelings can intensify in the second trimester. And as you grow more uncomfortable in the third trimester, your feelings of anxiety might grow as well. For some mothers, these emotions can be more intense than usual, leading to severe anxiety symptoms or depression. And while some of the blame can be placed on the stresses of becoming a parent, we can also blame the hormones for changing the chemical balance in the brain.

But this all helps the mother to prepare for childhood by being less responsive to stress and more responsive to her child. Although it seems like all it does is change your cognitive processes or functions, it’s really helping you to be a more sensitive mother. For example, some studies actually show that when a fetus moves, the mother’s heart rate, emotions, and skin conductance increase, even if she’s not aware of the movement. A hormone, called oxytocin, also plays a major role in pregnancy. It helps to contract the muscles of the uterus during birth and is actually used by doctors to slow down bleeding during birth. And during pregnancy, the hormone helps the mother feel calmer, get more sleep, and to get more nutrients, to help with her energy levels. Once the baby is born, oxytocin is released by both mother and baby, which helps to create a sense of euphoria and to foster the mother-child bond. Want to read more about the types of neurotransmitters?

Pregnancy changes the brain

Pregnancy changes the brain- Pregnancy brain explanation

In an article published by Lisa Galea 2014 “Mother’s Day Science: From ‘Baby Brain’ to Cognitive Boost”  it was stated there are studies that provide evidence yielding that a female brain shrinks between 4 to 8 percent during pregnancy which causes a mother to be forgetful which is also called as “baby brain” or “pregnancy brain”. In addition, Galea also stresses that the changes in the brain occur due to the elevated levels of progesterone and estrogen hormones which further results in memory impairments in a pregnant female.

 Even if we place some of the blame on the hormones, only some studies show cognitive deficits during pregnancy. In fact, other studies actually show that pregnant women perform just as well as other women in cognitive tests. So what really is to blame?

Well, some people argue that, while the hormones are preparing you for motherhood, it’s directing your attention away from things you would normally pay attention to. Combine that with worries about the baby, your health, and sleep deprivation, it’s a wonder you can even function at all! So the bottom line is, just because your brain feels a little “foggier” than usual, doesn’t mean you’re losing any IQ points. It just means that your brain is getting you ready to be the best mom you can be. It means that pregnancy changes your brain in fact but in a positive way. Luckily, you can still train your brain with cognitive brain training programs, which will help you keep your cognitive skills in top shape throughout your pregnancy!

Pregnancy changes the brain: Your brain after birth

The fogginess felt during pregnancy eventually goes away after birth. And while your brain is trying to rebalance its chemistry, it’s also directing its activity to places that will help you as a mother. For example, during pregnancy, activity increases in areas controlling social interactions, empathy, and anxiety. In the postpartum period, these changes are amplified by even more hormone surges. In addition, a mother will start to feel overwhelming emotions of love, protectiveness, and worry about raising a baby. You can see the crazy effects of how pregnancy changes the brain!

Some research has shown that there is growth in the amygdala and the hypothalamus. This helps with emotional regulation, survival instincts, and the production of hormones. This growth increases weeks and months after birth. This has been linked to mothers having a positive view and positive feelings towards their baby. It also allows a mother to wake up in the middle of the night when their baby is crying, without getting too frustrated as explained in the video.

Knowing about all of these emotional changes allows us to understand things like postpartum depression, obsessive compulsions, and anxiety. In fact, amygdala damage is associated with higher depression rates in mothers. Studies also show that reward centers (such as the thalamus and amygdala) in the brain actually light up whenever a mother just stares at her baby. This causes the attentiveness and the affection a mother feels towards her baby. But in depression, this activity isn’t as prominent.

The process of childbirth is the most beautiful experience that a woman goes through and what is more amazing is to learn the changes her body goes through prior and post pregnancy. Researchers and neuroscientists are working to investigate more about how pregnancy changes the brain and body. As studies are being published, there are other questions that may arise, like “would brain change have a negative effect on a woman if she gets pregnant more than once?”

How to keep your brain sharp?

Pregnancy changes the brain can be overwhelming and it can add greatly to your stresses. Follow these tips to keep your brain sharp, and to keep you mentally healthy!

  1. Sleep deprivation can lead to much of the forgetfulness experienced during pregnancy. Not having enough sleep prevents the brain from focusing on caring for your baby. So the answer is obvious, get more sleep! This might seem like an impossible task, but getting at least 8 hours a night can really help you feel back on your feet. Fight the urge to be productive while the baby is napping and instead, opt to take a nap. And when the baby wakes up in the middle of the night, try to trade it off with your partner, so you feel less groggy in the morning.
  2. Write things down. Or more specifically, write everything down. Writing will help you greatly in trying to remember things. Not to mention, having everything in one place will keep you sane. Invest in a planner or notebook, and carry it with you everywhere, so you’re always on top of things.
  3. As established before, try playing some brain games. Brain games allow you to use your cognitive abilities and stimulate your brain using specific training exercises. CogniFit offers a large variety of free online mind games, which are specifically designed to target your overall brain health.

However, with the studies published, we can now confidently say that the changes that occur in a female’s brain due to the reduction in the gray matter are a positive change for both the mother and the child.

Do you have any questions or ideas? Leave a comment below! 🙂

References

Hoekzema E, et al. (2017) Pregnancy leads to long-lasting changes in human brain structure. Natural Neuroscience 20, 287–296.

 

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.