Emotions are not only essential in life, they give the flavor to your life as well. Without them, life would be dull but also your information processing would be making much more mistakes. Feelings closely work together with your cognitive (information processing) system to handle yourself, your world and others. Brain injury can change all this.
The most common complaint of family members is that their partner is changed, in his or her emotional reactions. Meaning: less emotionally stable. If someone was quite in balance, after the brain injury there can be sudden outbursts of aggression or anxiety. Mood changes tend to come more frequently and much more intense than they used to be. Control over such outbursts seems to be reduced. It is as if someone has more stress than before and can not handle it effectively anymore.
Science dictates that there are six basic emotions: anger, fear, sadness, joy, disgust and surprise. Actually, one scientist Ekman made this divisions after studying facial expressions all over the world. I and especially some philosophers disagree with this list and I believe that there are only 4 basic emotions. The rest is just a derivative of these 4. The four fundamental basic ones are: anger, fear, sadness and last but not least: joy. As you can see, nature has provided us and most higher animals with 75% negative feelings. Joy is clearly in the minority. I always can speculate quite simply why this is so. I always tell my patients how they can imagine that in the jungle a group of lions can survive if joy would be the most important emotion. Ever seen only happy lions around? Just laughing? When seeing a deer or a gazelle, they would just laugh? Can you imagine how long such lions would survive out there? Evolution is also the reason that fear is the most predominant emotion in most higher animals, and also in man. Sadness is a special case and it only exists in higher animals, not in reptiles. Ever seen a crocodile grieving or sad (as far as we can tell)?
Although feelings are very useful and even necessary for survival, we as human beings have one fundamental task: to control them and not getting overwhelmed by them. I realize that 'control' is kind of a nasty word here, but I do mean that we have to regulate the intensity of our feelings. Imagine being scared all the time with an intensity of 8 or 9 on a scale of 1(least) to 10 (max). That is not only very unpleasant, it is devastating for your life as well. You will not do the right things when you are in such a state of fear. Imagine being sad all the time, just crying for hours and hours. It is not only very unpleasant, but you will not do much in such a state. A true depression is even worse because you are not even sad anymore, you are beyond sadness and do not feel any pleasure at all anymore. You are then a 'zombie'.
Controlling your feelings has everything to do with your brain and your cognitions (your ideas). Whether ideas or concepts are very consciously experienced by yourself, or more automatically triggered without you not knowing it very much, ideas are thé key to regulation of your feelings. In my page about Emotions and stress in a 'normal' brain state, I will explain more about my model of the relationship between feelings, ideas, stress and your brain. For now, it is very important to remember the following formula which kinda sums it all up: feeling = emotion + idea.
A feeling can normally be felt consciously, although there are people who do not know or are not aware of their feelings. An emotion is the physical expression (in fact, all bodily changes): sweating, hart pounding, blood flow, increased neurotransmitters like serotonin or adrenalin, blood pressure changes. These changes are normally controlled automatically by our vegetative or autonomic nervous system. An idea is an information processing concept: it can be a consciously perceived idea express in words, or a more not yet conscious preconcept of something, or an image. Having read a lot of literature about psychotherapy, psychiatry, but also having treated hundreds of patients having emotional problems, I have become pretty convinced that this formula is quite correct. Also I have become pretty darn sure that the only way to regulate our feelings is through the control of our cognitions/ideas.
The philosophy that only ideas can regulate or control our feelings is quite old and goes as far back as the old greek philosophers. But I believe that the Persians and the Chinese (Confucius) already knew this as well.
There is a model, the triune brain theory of MacLean (1970), that states the following 3 layers in our brain: 1) the proto-reptilian system of spinal cord, brain stem, diencephalon and basal ganglia, which controls all genetically-programmed survival behaviours and a range of basic physiological functions such as heartbeat, breathing, digestion, et cetera; 2) the paleo-mammalian ‘limbic’ system, comprised of amygdala, hypothalamus and hippocampus, which generates self-awareness and attendant emotional responses; and 3) the neo-mammalian cerebral cortex, responsible for foresight, insight, reason, speech, problem solving, visuospatial capacities. Of course, as all theories, this is just a simplification of the reality. But it is based on evolutionary science which has demonstrated that our brain has evolved roughly according to these layers. In other words, our cognitions or information processing units are largely built upon evolutionary older systems like the reptile brain structures and the mammalian brain. We are in fact built upon our emotional brain!
Everyone can experience this whenever fear or sadness takes control over our thoughts and actions: when being in total panic you are really not able to control yourself. Anxiety is completed taking over your information processing, so to speak.
It is only when our cognitive functions are developed and trained sufficiently, we can regulate our basic feelings sufficiently to behave adaptively and effectively. That is what we are doing when we are driving in a high-speed car. Normally, anxiety would cause panic when noticing we drive that fast. But due to our concepts about car driving, our notions about how safe a car is when someone drives it who has learned to drive, we do not panic. But just imagine that you are in that same car and the passenger next to the driver surprises you with the message that the driver has just learned how to put his foot on the accelerator. And does not have a driver's license at all! Guess what your upcoming emotion will be when the car is doing 120 miles an hour! Just imagine what happens when we put a Neanderthaler in such a high-speeding car.
I just want to make clear that our feelings are intricately intertwined with our cognitions and that they are regulated by our cognitions, either knowingly or more unconsciously. So when brain damage hinders the cognitive processing, it is pretty logical that the regulation of our feelings becomes much more difficult. And that is exactly what happens in clinical practice: brain injured patients can not control their feelings as effectively as healthy people can. Either, some feelings are much more intensified, or...they are reduced. The ins and outs of such numbing of feelings is not fully understood yet but it seems to have something to do with changed neurotransmitter balances in the damaged brain. But again, this area is still not understood very much. We do know however, that when we use drugs (we call them 'medicines'), the brain will react and someone's feelings change in intensity.
The take-home message here is that the normal control of our feelings is compromised by a brain damage. The very badly chosen wording 'emotional impulses' are now free-floating more than ever. Meaning, feelings will pop up in a more uncontrolled (hence impulses), sudden manner, usually in reaction to your environment (either internal or external).
Most common behaviors after brain injury are uncontrolled emotional outburst like anger: cursing violently, throwing with things, and sometimes even hitting someone. Panic attacks are possible as well. But almost always anger or aggression is the first clear expression. Again, very logical because aggression is in fact a very good self-protective feeling. It really protects someone by chasing away every possible attacker, and giving the irritated person more strength and confidence.
When anger is reduced in whatever way, two other feelings may surface: either fear or sadness. In little children this can be seen beautifully when first demanding a cookie violently and then starting to cry when realizing mum will not give in. I always use this example to convince people that whenever there is some kind of anger, there always is a deeper sadness or fear around. Focusing on these deeper emotions (either fear or sadness) is the way to get rid of the anger (NOT the other way around).
Another reason feelings can not be controlled that well after brain injury is fatigue. Everyone knows that when fatigued, meaning we do not have that much energy left and our information processing system is functioning less clearly, we get much more quickly irritated or anxious. Because brain injury leads much quicker to fatigue and the feeling of being overwhelmed, anxiety or sadness can kick in much sooner. To protect oneself for these feelings, the first reaction will again be...anger.
You can imagine that when someone is having lesser control over his condition or environment, due to cognitive defects, feelings like sadness or fear will come sooner. Stress will come sooner. Not being able to control the intensity of such feelings, will lead to even more stress. So it becomes very important to explain a brain injured patient the fundamentals of emotional control. In my pages about Brain treatment and rehabilitation I will explain more about how to control feelings after brain damage.