Tag Archives: brain functions

Limbic System Functions: Limbo With Your Limbic System

Your limbic system functions range from regulating your emotions to storing your memories to even helping you to learn new information. Your limbic system is one of the most essential parts of the brain that help you live your daily life. The primary structures that work together in your limbic system are the amygdala, the hippocampus, the thalamus and hypothalamus, the cingulate gyrus, and the basal ganglia. All these parts help you to be active in society, engage in social relationships, and be a well-rounded person. To learn more about the interesting ways your limbic system impacts your life, sit back and get in-tuned with all of its hard-working employees!

Limbic System Functions
1. What is another name for your amygdala?
  • Your amygdala is essential for controlling the emotions that you express. That is why it is called ''the emotional center of the brain.''
2. What is your basal ganglia involved with?
  • Your basal ganglia is the main structure that controls all of the voluntary movements your body performs
3. Where do hormones originate in the brain?
  • Your hypothalamus is controlled by the pituitary gland which regulates how many and what hormones are released throughout your body (this is all under the endocrine system)
Limbic System Functions

Limbic System Functions

Interconnected nuclei and cortical structures located in the telencephalon and diencephalon have different functions that are related to the limbic system. These nuclei main functions are of self-preservation. They regulate our autonomic and endocrine function especially as a response to emotional stimuli.

Many of the areas are related to memory and with arousal levels involved in motivation and reinforcing behaviors. Since it’s related to self-preservation, many of the areas are related to the sense of smell, since it is critical for survival.

The areas critical for functions in the limbic system are two:

  • Subcortical structures include the olfactory bulb, hypothalamus, amygdala, septal nuclei and thalamic nuclei.
  • Cerebral Cortex also is known as the limbic lobe it includes the hippocampus, insular cortex, subcallosal gyrus, cingulate gyrus and parahippocampal gyrus.

Here are some of the different parts of the limbic system and how they affect you:

Limbic System Functions: The Amygdala

Shaped like a small almond, the amygdala is located in each of the left and right temporal lobes. It’s known as  “the emotional center of the brain,” because it is involved in evaluating the emotional intake of different situations or emotional intelligence (for example, when you feel happy because you received an awesome grade on your math exam or when you might be frustrated because the heavy traffic is making you late for work). The amygdala is what makes the brain recognize potential threats (like if you are hiking in the lone woods and suddenly you hear the loud footsteps of a bear coming toward you). It helps your body prepare for fight-or-flight reactions by increasing your heart and breathing rate. The amygdala is also responsible for understanding rewards or punishments, a psychological concept known as reinforcement coined by the classical and operant conditioning experiments of Ivan Pavlov.

The amygdala works by being stimulated through the electrical forces of neurotransmitters (understand the different types of neurotransmitters). Many times, when this stimulation is very high, we show physical acts of aggression, like throwing tantrums, screaming, or hitting objects. If the amygdala was removed from the human brain, then we would all become extremely tame and no longer respond to things that previously caused us frustration or annoyance. Also, we would become indifferent to all forms of external stimuli, especially those related to fear and sexual responses.

Limbic System Functions: The Hippocampus

This part of the brain is found deep within the temporal lobe and is shaped like a seahorse. The exact role of the hippocampus is disputed between psychologists and neuroscientists, but we generally know that it is essential in forming new memories about past experiences. The three major stages of memory forming in the brain are:

1. Sensory input from your peripheral nervous system sending neurotransmitters to your brain

2. Your brain storing those stimuli in its “short-term memory,” which holds the information for about 3-5 minutes

3. If 5 minutes has elapsed and you are still thinking about that memory, then it will enter into your long-term memory, where it will stay for virtually an endless period of time.

Your hippocampus is the main brain portion responsible for going from stage 2 to stage 3, or converting short-term memories to long-term memories.

Researchers suggest that the hippocampus is responsible for “declarative memory,” which is the ability for one to explicitly verbalize their memories (i.e. episodic memories and semantic memories).

Limbic System Functions

If the hippocampus is damaged, then a person will not be able to build new memories (known in neuropsychology terms as anterograde amnesia) although he or she might be able to hold onto older memories. This individual would instead live in a very strange world where everything they experience and everyone knew whom they meet just fades away. A classic example of this is seen in the movie 50 First Dates, where Drew Barrymore plays the lead role of a girl with short-term memory who loses memory every night being with her beloved during the day.

Limbic System Functions: The Thalamus

These structures are both associated with changes in emotional reactions. The thalamus is known as the “way-station” of the limbic system because it aids in communicating what is going on in the system with the rest of the brain. It connects areas of the cerebral cortex that are involved in sensory perception and movement with other parts of the body associated with sensation and movement. It has control over your peripheral nervous system, which moves sensations from the body through the spinal cord into the brain. Specifically, it works alongside these major lobes in the brain:

  1. The parietal lobes – it sends sensory touch information to the somatosensory cortex located here
  2. The occipital lobes – it sends visual information to the visual cortex here
  3. The temporal lobes – auditory signals are sent to the auditory cortex here

The thalamus has other functions for your body as well, like controlling your sleep and awake states of consciousness. It sends signals from the brain to the rest of the body to reduce your perception of sensory information while sleeping, which is why you wouldn’t necessarily feel if an ant was crawling on you or someone put their hand on your arm gently while you were sleeping. The thalamus also is involved in motor controls, relaying sensory signals to the cerebral cortex, forming memories and expressing emotions, and perceiving pain.

Limbic System Functions: The Hypothalamus

The hypothalamus is a small piece located just below the thalamus and has lesions on it that are the driving forces behind our major unconscious activities, like respiration and metabolism. One of its central functions is homeostasis for the body, which is returning it from either too much excitement or too little pleasure to a calm “set-point” from which we behave “normally.” It is one of the busiest parts of the brain because it also helps drive other motivated behaviors like hunger, sexuality, and aggression. The lower side of the hypothalamus seems to be involved with pleasure and rage, while the middle section is associated with displeasure, aversion, and uncontrollable and loud laughter. Because the hypothalamus also regulates the functions of your autonomic nervous system, it controls things like your pulse, blood pressure, breathing, and arousal response to emotional circumstances.

Recent biological studies have shown that when we overeat, a protein called leptin is released by fat cells in our bodies. The hypothalamus is the first part of the brain to sense these high levels of leptin in the bloodstream so it will respond by decreasing our appetites. Some research suggests that some people have a mutation in the gene which produces leptin, so their hypothalamus is unable to recognize that they are overeating. However, there are many overweight individuals studied who do not have this mutation, so work is still being done in this research idea.

The hypothalamus also works in coordination with the pituitary gland, known as the “master gland.” It is chemically and neurally related to the pituitary gland, which as a result of its control, pumps hormones called releasing factors into the bloodstream. The pituitary gland has the central control over your endocrine system, so it releases hormones that are essentially important to regulating growth and metabolism for you.

 Limbic System Functions: The Cingulate Gyrus

This part is located in the middle of your brain next to the corpus callosum. Not much is known about the cingulate gyrus, but researchers suggest that this is the area that links smell and sight with pleasurable memories of previous experiences and emotions because it provides a pathway from the thalamus to the hippocampus. This area is involved with your emotional reaction to pain and how well you regulate aggressive behavior.

The anterior cingulate gyrus deals with the vocalization of emotions. It has connections with speech and vocalization areas of the frontal lobe, which includes Broca’s area, a brain piece that controls motor functions involved with speech production. People with Broca’s aphasia, or an impairment in their Broca’s area, are unable to fluently produce speech to convey what exactly is in their mind but they are able to fully comprehend the speech and writing of others.

The cingulate gyrus also is involved in the emotional bonding and attachment between a mother and her child because of the frequent vocalization that takes place between mothers and their infants, so children feel deeply attached to the voices of their mothers. Because the cingulate gyrus is connected with the amygdala, it processes emotions and is responsible for fear conditioning and relating memories to sensory information received from the thalamus.

Limbic System Functions: The Basal Ganglia

This area is an entire system within itself located deep in the frontal lobes. It organizes motor behavior by controlling your physical movements and inhibiting your potential movements until it gets the instructions to carry them out, based on the circumstances that you are in. The basal ganglia also participate in rule-based habit learning; choosing from a list of potential actions; stopping yourself from undesired movements and permitting acceptable ones; sequencing; motor planning; prediction of future movements; working memory; and attention.

In general terms the limbic system functions are as follows:

  • The sense of smell: the amygdala directly intervenes in the process of olfactory sensation.
  • Appetite and eating behaviors: The amygdala and the hypothalamus both act in this behavior. The amygdala helps in food choice and emotional modulation of food intake. Meanwhile, the hypothalamus controls the intake of these foods.
  • Sleep and dreams: While dreaming, the limbic system is one of the most active brain areas according to different neuroimaging techniques. The hypothalamus also intervenes in this case particularly the suprachiasmatic nucleus of the hypothalamus that controls the sleep-wake cycle through circadian rhythms.
  • Emotional Responses: Limbic system functions include modulating emotional responses of fear, rage and endocrine responses of fight or flight responses. In these responses, the amygdala, the hypothalamus, the cingulate gyrus and even the basal ganglia’s motor tasks work together.
  • Sexual Behavior: The limbic system also takes part in the sexual behavior through the hypothalamus and different neurotransmitters, specifically dopamine.
  • Addiction and motivation: Addiction is highly related to your reward system which in part is controlled by the amygdala. Therefore it’s important to know this when treating addicts. Relapse is usually related to the release of excitatory neurotransmitters in brain areas such as the hippocampus and the amygdala.
  • Memory: As we mentioned before emotional responses are related to the limbic system. Emotions are is also involved in the retrieval and consolidation of memory, therefore one of the limbic system functions is the emotional memory. Other memories that have influence from the limbic system are medial temporal lobe memory system in charge of making and storing new memories. As well as, Diencephalic memory system related to the storage of a recent memory, a dysfunction of this circuit results in Korsakoff’s Syndrome.
  • Social Cognition: This refers to thought processes involved in understanding and dealing with other people. Social cognition involves regions that mediate face perception, communication skills, emotional processing, and working memory. They help the complex behaviors necessary for social interactions. Limbic structures involved are the cingulate gyrus and amygdala.

To end this fantastic article we leave a video with a song to learn the limbic system functions. Hope you enjoyed the article and feel free to leave a comment below.

https://www.youtube.com/watch?v=B-RLFEWTqsY

Synapses: How Your Brain Communicates

A synapse is the space between two neurons which allows for neural communication, or synaptic transmission. Synapses are found throughout the body, not just located in the brain. They project onto muscles to allow muscle contraction, as well as enable a multitude of other functions that the nervous system covers.

It might be helpful to familiarize yourself with neuron cell body and structure and function when understanding the synapse!

Synapses

Parts of a Synapse

As a synapse is the gap in between two neurons, we need to establish which neuron sends out the signals and which neuron receives those signals.

Parts of a Synapse: The Role of the Presynaptic Neuron

The presynaptic neuron is the neuron that initiates the signal. At many synapses in the body, presynaptic neurons are vesicles filled with neurotransmitters. When the presynaptic neuron is excited by an action potential, the electrical signal propagates along its axon towards the axon terminal. This excitation signals the vesicles in the presynaptic neuron, filled with neurotransmitters, to fuse with the membrane of the axon terminal. This fusion allows for the neurotransmitters to be dumped into the synaptic cleft.

Once the neurotransmitters are released, they can act on receptors on the postsynaptic neuron.

Types of neurotransmitters

Parts of a Synapse: The Role of the Postsynaptic Neuron

The postsynaptic neuron is the neuron that receives the signal. These signals are received by the neuron’s dendrites. When there are neurotransmitters present in the synapse, they travel across the gap in order to bind to receptors on the postsynaptic neuron. When a neurotransmitter binds to a receptor on the postsynaptic neuron’s dendrite, it can trigger an action potential. That action potential can then be propagated and influence further communication.

Where Are Synapses Located in the Brain?

Synapses are found throughout the nervous system. They allow for complex thought, coordinated movement, and most of our basic functions. Synapses are located in the brain and spinal cord, which make up the central nervous system, and the peripheral nervous system, which includes neural projections onto muscle cells.

The Neuromuscular Junction

A good example of the location of synapses in the body is the neuromuscular junction. A neuromuscular junction is made up of a motor neuron and a muscle fiber, which is part of the peripheral nervous system. In this case, there is no postsynaptic neuron, but the muscle fiber has a specialized area that acts synonymously to how a postsynaptic neuron would respond. This area is called the motor end plate and has receptors that bind with the neurotransmitters released into the synapse.

In a neuromuscular junction, presynaptic neurons release acetylcholine as the neurotransmitter. At the neuromuscular junction, acetylcholine excites the muscle fiber and causes muscle contraction.

The presynaptic neuron in the neuromuscular junction needed to be told to release acetylcholine into the synapse. This doesn’t occur through the neuron’s own volition, but rather through a series of other neurons communicating with each other through synapses.

What do Synapses do?

It has been established that synapses are important in neural communication, but what do synapses actually do? How do they really allow for neural communication, and who starts the conversation?

When introducing the role of the presynaptic neuron above, the excitative qualities of an action potential were mentioned. Action potentials are the way that neurons can send information they receive down their axons and, hopefully, initiate the continuation of the signal to another neuron. These action potentials are created by a depolarizing current.

Action potentials allow for electrical signals to be sent down a neuron’s axon, and then the signal can be transmitted to the other neurons by a synapse. As stated before by introducing the role of the presynaptic neuron, neurotransmitters are released into the synapse in order for the signal to be transmitted to the next neuron. The chemical release is then received by the postsynaptic neuron and then converted back into an electrical signal in order to reach other neurons.

Although, not all synapses function on chemical or neurotransmitter release. Many synapses in the brain are purely electrical.

Types of Synapses

In the nervous system there are two main types of synapses: chemical synapses and electrical synapses. Thus far, for simplicity and understanding the basics of how a synapse functions only chemical synapses have been discussed. This poses the question: why does the nervous system need two types of synapses?

Types of Synapses: Chemical Synapses

Chemical synapses are any type of synapse that uses neurotransmitters in order to conduct an impulse over the small gap in between the presynaptic and postsynaptic neurons. These types of synapses are not in physical contact with each other. Since the transmission of a signal depends on the release of chemicals, a signal can only flow in one direction. This direction is downward from presynaptic to the postsynaptic neuron. As previously stated, these types of neurons are widely spread throughout the body.

The chemicals released in these types of synapses ways excite the following neuron. The neurotransmitters can bind to the receptors on the postsynaptic neuron and have an inhibitory effect as well. When inhibition occurs, signal propagation is prevented from traveling to other neurons.

Chemical synapses are the most abundant type of synapse in the body. This is because various neurotransmitters and receptors are able to interpret signals in a large combination. For instance, a neurotransmitter and receptor combination may inhibit a signal on one postsynaptic neuron, but excite a large amount of other postsynaptic neurons. Chemical synapses allow for flexibility of signaling that makes it possible for humans to engage in high-level tasks. However, this flexibility comes at a cost. Chemical synapses have a delay due to the need for the neurotransmitter to diffuse across the synapse and bind to the postsynaptic neuron. This delay is very small but still is an important point when comparing the two types of synapses.

Types of Synapses: Electrical Synapses

Synapses

Electrical synapses are types of synapses that use electricity to conduct impulses from one neuron to the other. These synapses are in direct contact with each other through gap junctions. Gap junctions are low resistance bridges that make it possible for the continuation of an action potential to travel from a presynaptic neuron to a postsynaptic neuron.

Due to their physical contact, electrical synapses are able to send signals in both directions, unlike chemical synapses. Their physical contact and the use of sole electricity make it possible for electrical synapses to work extremely fast. Transmission is also simple and efficient at electrical synapses because the signal does not need to be converted.

Another key difference between chemical and electrical synapses is that electrical synapses can only be excitatory. Being excitatory means that an electrical synapse can only increase a neuron’s probability of firing an action potential. As opposed to being inhibitory, which means that it decreases a neuron’s probability of firing an action potential. This can only be done by neurotransmitters.

Despite being extremely fast, these types of excitatory signals can not be carried over great lengths. Electrical synapses are mainly concentrated in specialized brain areas where there is a need for very fast action.

The best example of this is the large amount of electrical synapses in the retina, the part of the eye that receives light. Vision and visual perception are our dominant senses, and our eyes are constantly receiving visual sensory information. This information also runs on a feedback loop when we interact with our environment, which means that we receive information from our surroundings and immediately create an appropriate response to it. This is why it makes sense that electrical synapses are seen in a large concentration here. The fast action, multiple directions, and efficiently all allow for prime functionality.

Synapses in Neuroscience

Understanding synapses allow neuroscientists to further understand how communication within the brain works. This is extremely important when trying to decipher causes, and eventually, develop treatments for neurological diseases and disorders.

Knowing about synapse function is not just beneficial to neuroscientists, it is beneficial for anyone with a brain! Increased synaptic density can improve the quality of life for anyone, it is essentially a tactic for making your brain work smarter.

Natural Ways to Improve Your Synapses

1. Reduce Stress

Too much stress, as well as long periods of stress, can have harmful impacts on the body, especially the brain and nervous system. By reducing stress, you are reducing the amount of cortisol that is circulating throughout your body. Cortisol is important if you need to outrun a bear, but elevated levels in your daily life can damage chemical synapses all over the body. Stress and aging are also closely related, so controlling your stress levels may help you prevent early aging.

Chemical synapses are susceptible to desensitization, which will occur is abnormally high concentrations of a neural transmitter are fighting to stimulate a neuron.

2. Stimulate Your Brain With CogniFit Brain Games and Cognitive Assessments

It is important, at any stage in life, to keep your brain stimulated. Our synapses play an important role in keeping our brains healthy and helping them improve over time, rather than fall victim to the natural cognitive decline that occurs as we age. With the consistent training and challenging of the brain, the synapses work to perform better and more efficiently, ultimately making it possible to improve the cognitive function that may have seemed lost. This is the idea behind brain or neuroplasticity and is the basis of CogniFit’s program.

CogniFit’s  brain training system works by adapting the games and tasks to each user’s cognitive level, ensuring that the brain, its neurons, and all of the synapses involved are being trained and challenged as efficiently as possible.

3. Exercise

Exercise is very important in keeping the brain healthy. People often get frustrated within the first few weeks of a new workout regime when physical changes are not yet visible. It turns out that the first changes of regular exercise are actually neurological, starting in the brain. Exercising promotes brain growth by increasing oxygen levels in the brain. Brain growth first starts at the synaptic level. Read more about the benefits of exercise on the brain!

Your Synapses

Hopefully, now that you’re familiar with the basic structure, ins and outs, functions, and types of synapses in the brain you can think about what is happening on a microscopic level to ensure your body is functioning at top notch. Small improvements on the synapse level can have a large effect on your overall health.

Test Yourself!

4. What is a presynaptic neuron?
5. What is a postsynaptic neuron?
6. What is one difference between an electrical and chemical synapse

MIT brain scans show that entrepreneurs really do think differently

Entrepreneurs really do think differently

MIT brain scans show that entrepreneurs really do think differently.

A brain scan study at MIT suggests that entrepreneurs are more likely to use both sides of their brains when making decisions.

Successful decision-making isn’t necessarily about doing more exploration than exploitation. It’s in the timing – knowing when to shift between the two forms of thinking. A question for further research is whether entrepreneurs’ brains function this way because of the kind of decisions they’re used to making, or whether people with these more coherent brains are more likely to end up as entrepreneurs.