The Heart Brain System – Part 2

By: Michael Lam, MD, MPH; Justin Lam, ABAAHP, FMNM; Carrie Lam, MD


Read Part 1 | Part 3

Heart Rhythm Patterns – Coherence and Incoherence

Heart brain system and emotional stabilityWe’re going to be using the terms coherence/coherent and incoherence/incoherent throughout the rest of the article, so it’s important you understand what they mean, when it comes to the heart brain system.

Coherence in HRV means there is an order and stability to the waveform pattern. The heart rhythm has more rounded and coherent waveforms. Incoherence in HRV means that the waveform patterns are erratic and have jagged, sharp peaks. The heart rhythm has more incoherent waveforms.

Coherence reflects positive emotional states such as appreciation, courage, love, enthusiasm, etc. Incoherence in HRV shows negative emotions, such as frustration, anxiety, worry, irritation, etc. At this point in time, it’s possible to determine someone’s emotional state with 75% accuracy just from their heart rhythm, including the differences in negative emotional states, such as anger or worry, for example.

HRV rhythm has a strong and direct impact on mental and physical performance, with coherence facilitating cognitive functions and reinforcing emotional stability and positive emotional states. Different independent studies confirm that coherence is the best state for this, as well as for regenerating natural physical processes.

Incoherence, on the other hand, inhibits brain function, social and situational awareness, the ability to self-manage, and the capacity to care.

Another distinction we have to make is the one between coherence and relaxation, because although they seem related, in fact they are not. In fact, some coherence techniques are quite the opposite of relaxation techniques.

For example, coherence techniques are used with professional athletes, Olympic athletes, and military and law enforcement. There is a resilience program for the US Navy based on coherence techniques. In all of these fields, the goal is not to shift the participants into a relaxed state before a match or a drill, but rather to get them into a peak performance state. This is done through coherence, where the body and brain are in a state of synchronization.

Coherence can be achieved at any heart rate, and with practice you can have a coherent heart rhythm even with a heart rate over 100. It can also be done with slow heart rates, or when you’re in a “relaxed state.” It’s also interesting to note that you can be in a “relaxed state” with a low heart rate while your heart rhythm is incoherent.

This is not to say that relaxation is not a good skill to learn; it certainly is. But it’s different from a coherent heart rhythm, and the ideal would be to have both of these tools in your toolkit.

The Heart Brain System Pathway

There are several areas of the brain that are in direct communication with the heart.

  • The cortex: the thinking brain
  • The thalamus: which synchronizes the cortical activity
  • The amygdala: which houses emotional memory
  • The medulla: which regulates the ANS and blood pressure

The pathway to the amygdala is only one synapse away; it is a direct neural pathway. The cells in the core nucleus of the amygdala are all synchronized with the cardiac cycle. This means that every time the heart beats, cells in that core nucleus fire with it. This is why the amygdala reflects the heart rhythm patterns.

The thalamus has many different functions, including synchronizing the electrical activities of neurons. It also has a direct pathway to the heart, and when you get an incoherent heart rhythm pattern that affects the thalamus, this in turn inhibits cortical synchronization.

The prefrontal cortex and the frontal cortex help with reaction times, the coordination of tasks, and perhaps most importantly, give you the ability to understand and predict how your current actions and behaviors might affect your future. This can include such complex things as setting goals, the feeling of achievement, planning, and the ability to discriminate what the appropriate behavior is in specific contexts.

When the cortex is desynchronized, all of these abilities become inhibited. That’s why, for example, you can see difficulties in impulse control, problems with behavioral regulation, and a lack of foresight.

Desynchronized cortex of the heart brain system during a heated argumentAn example that you might be familiar with: let’s say you get into a heated argument and you shout or say something out of character. A short while later you are perplexed, regretting the outburst and wondering if you had lost your mind for a moment. But actually, that was just an inhibition of your cortex, which happened in milliseconds, much faster than any hormonal changes!

But let’s say that you’ve been practicing techniques that bring coherence to your HRV rhythm. Due to the direct pathways of your heart brain system, you now have synchronization with the cortex, and you’re able to have faster reaction times and more self-regulation. That is good news, including for your hormones.

Speaking of hormonal effects, although they may be slower than the heart brain system connections, they are still a very important element to the NEM as well as every other system in the body. Sometimes, hormones may already be off-balance and adversely affecting the heart and the brain. This is something we see in conditions like AFS, for example. If that’s your case, read on.

Stress Hormones and The Nervous System

The ANS, which, as we’ve mentioned, is a great indicator of stress and has important functions in the heart brain system, is part of the peripheral nervous system, one of the two main branches of the nervous system. The other main branch of the nervous system is the central nervous system.

The word “autonomic” means “unconscious and involuntary.” The autonomic nervous system controls metabolic and physiological processes that are not conscious, though some aspects of them may be influenced consciously for a period of time. These include the respiratory system, the cardiovascular system, the gastrointestinal system, the immune system, and the endocrine system.

The ANS itself has 5 branches. The most well known is the sympathetic nervous system (SNS) – which is all about exertion and energy expenditure, like exercise, stress, oxidation, and being awake – and the parasympathetic nervous system (PNS) – which is all about relaxation and energy recovery, like rest and sleep.

The ANS works intimately with the NEM, and is especially prominent in the NEM’s neuroaffect response. The gut, the brain, and the ANS work as a team to manage the neuroaffect response, with the hypothalamus and pituitary gland in the brain acting as the hormone and metabolism supervisors.

These two control centers in the brain are also part of the HPA axis of your hormonal response, which we can consider to be the “first responder” to stress. It is a hormone cascade that sends signals from the brain to the adrenal glands to secrete cortisol. Once the cortisol has finished the job, any excess is used as a message to the brain that stimulating the adrenals is no longer necessary.

But the hypothalamus and pituitary gland communicate with many other organs and systems, also by either stimulating them or inhibiting them.

Heart brain system and stressClosely linked to the nervous system and the neuroaffect response is the cardionomic response of the NEM, with the heart as its central figure. This response readies the heart, blood vessels, and lungs for the “fight or flight” response by increasing oxygen-filled blood flow. The signals that turn this response on are the hormones cortisol, epinephrine, and norepinephrine, which are regulated by the SNS.

But if you’re suffering from AFS, these responses are dysregulated, and you may find your “fight or flight” response constantly triggered and your cardiovascular system always on high alert. This is what is known as Reactive Sympathetic Overtone (RSO). In RSO, your body is so weak that it cannot produce any hormones to help you deal with stress. Instead it releases norepinephrine into your body. This can create the unpleasant experience of having faster than normal resting heart rates, strong heartbeats, heart palpitations, POTS-like symptoms, anxiety, irritable bowels, panic attacks, and even temperature intolerance. If your body continues to stay in this mode, eventually things may worsen and you can enter Reactive Sympathoadrenal Response. In this state, the body produces more epinephrine instead of norepinephrine and your heart is subsequently affected more as well.

Adrenal Fatigue and The Heart Brain System

If adrenal fatigue can cause these imbalances in the neuroaffect and cardionomic responses, then it is safe to say, from a Functional Medicine approach, that the opposite is also true. The nervous system and the cardiovascular system also have an effect on adrenal fatigue, whether positive or negative.

Heart brain system and anxietySome of the symptoms of AFS are quite similar to those you can get with heart rhythm incoherence, such as anxiety, depression, and brain fog, as well as an inability to handle stress, or inability to self-regulate.

This means two things:

  1. You can improve adrenal fatigue by bringing your heart rhythm to a state of coherence.
  2. You can increase your ability to get into coherence by strengthening your adrenal glands and recovering from AFS.

Cortisol, the adrenal hormone that is most affected by adrenal fatigue, is responsible for vital tasks such as regulating blood pressure and blood sugar levels, maintaining heart and blood vessel functions, suppressing the immune system after it has done its job, and neutralizing inflammation.

In the beginning phases of AFS, cortisol levels actually rise in order to meet the growing demand for stress reduction. But if you’re not able to manage your stress and it continues to be chronic, your adrenal glands become so overworked that at some point they are exhausted and you enter into the more advanced stages of AFS. This is when cortisol levels drop and your body is left to fight stress without one of its most valuable allies.

By recovering from adrenal fatigue, your cortisol levels get up to standard again, and so your hormonal response is capable of handling stress better. It’s one way to help you achieve a level of hormonal balance that can support you in reaching a synchronized state in your heart brain system.

Recovery from AFS will revolve around adopting a proper adrenal fatigue diet, getting lots of rest, improving the quality of your sleep, and getting the right kind (and right amount) of exercise. With more advanced stages, you’ll probably begin with adrenal breathing exercises, which also help with stress management. As you get a little stronger, you can move onto adrenal yoga exercises.

Of course, it goes without saying that managing stress is a must for recovering from AFS. Here is where utilizing the heart brain system can help.

Read Part 1 | Part 3

© Copyright 2018 Michael Lam, M.D. All Rights Reserved.


Heart brain system