Before I go into too much detail, I'll start off with some basic definitions to make sure everyone is on the same page:
Psychology (lit. "study of the soul" or "study of the mind") is an academic and applied discipline which involves the scientific study of human (or animal) mental functions and behaviors.
Psychological - mental or emotional as opposed to physical in nature; "give psychological support"; "psychological warfare"
Empathy, which literally translates as in feeling, is the capability to share another being's emotions and feelings.
Also, the intellectual identification of the thoughts, feelings, or state of another person; capacity to understand another person's point of view or the result of such understanding.
Empathetic - showing empathy or ready comprehension of others' states; "a sensitive and empathetic school counselor".
Empathic - the action of understanding, being aware of, being sensitive to, and vicariously experiencing the feelings, thoughts, and experience of another of either the past or present without having the feelings, thoughts, and experience fully communicated in an objectively explicit manner.
A Highly Sensitive Person (HSP) is a person having the innate trait of high sensitivity (or innate sensitiveness as Carl Jung originally coined it). This is a specific trait with key consequences that in the past has often been confused with innate shyness, social anxiety problems, inhibitedness, or even social phobia and innate fearfulness, introversion, and so on. Although the term is primarily used to describe humans, the trait is present in nearly all higher animals. (Wikipedia:HSP)
Latent inhibition (potential prevention) is a technical term used in Classical conditioning. A stimulus that has not had any significance in the past takes longer to acquire meaning (as a signal) than a new stimulus. It is "a measure of reduced learning about a stimulus to which there has been prior exposure without any consequence." One is practicing latent inhibition when one tries to ignore an ongoing sound (like an air conditioner) or tune out the conversation of others.(Wikipedia:Latent Inhibition)
The above definition might not make much sense now, but it will soon enough.
Low Latent Inhibition - Most people are able to ignore the constant stream of incoming stimuli, but this capability is reduced in those with low latent inhibition. Low latent inhibition seems to cause one person to be more distractible than another. Those of above average intelligence are thought to be capable of processing this stream effectively, enabling their creativity. Those with less than average intelligence, on the other hand, are less able to cope, and so as a result are more likely to suffer from mental illness and sensory overload.
(Please note that this is Wikipedia's definition, and not my own. It is, however, important for later)
Agoraphobia (from Greek ἀγορά, "marketplace"; and φόβος/φοβία, -phobia) is an anxiety disorder. Agoraphobia may arise by the fear of having a panic attack in a setting from which there is no perceived easy means of escape. Alternatively, social anxiety problems may also be an underlying cause. As a result, sufferers of agoraphobia avoid public and/or unfamiliar places, especially large, open spaces such as shopping malls or airports where there are few places to hide. Although mostly thought to be a fear of public places, it is now believed that agoraphobia develops as a complication of panic attacks. (Wikipedia:Agoraphobia)
Panic attacks are episodes of intense sudden fear or apprehension that are of sudden onset and of relatively brief duration. Panic attacks usually begin abruptly, reach a peak within 10 minutes, and are mainly over within 30 minutes. Panic attacks can be as short as 15 seconds, or can be cyclic, lasting for an extended period, sometimes hours. Panic attacks are distinguished from other forms of anxiety by their intensity and their sudden, episodic nature. They are often experienced in conjunction with anxiety disorders and other psychological conditions, although panic attacks are not usually indicative of a mental disorder. (Wikipedia:Panic Attack)
Posttraumatic stress disorder (also known as post-traumatic stress disorder or PTSD) is a severe anxiety disorder that can develop after exposure to any event that results in psychological trauma. Diagnostic symptoms for PTSD include re-experiencing the original trauma(s) through flashbacks or nightmares, avoidance of stimuli associated with the trauma, and increased arousal – such as difficulty falling or staying asleep, anger, and hypervigilance.
Now, none of these definitions may seem connected at first, but they are all the pieces to the puzzle we know as empathy and being an empath.
Genesis of the Empath
According to the definition of a Highly Sensitive Person, the trait is a neurological difference that can be measured. This essentially means that an increased sensitivity to things that happen around you is a physical trait as well as a mental one. In the popular understanding, this is where the genetic part comes into play. This is a natural born 'empath', i.e. one who was born sensitive.
The research on sensory-processing sensitivity, however, builds on Eysenck's views on introversion and arousal and Gray's work on the inhibition system. This research in turn builds on Pavlov's work on sensory response to both physical and mental over-stimulation, and work by Jung and his contemporaries differentiating extroverted and introverted cognitive sensitivity types. This research shows that about 15-20% of humans and higher animals have a nervous system that is more sensitive to subtleties. This means that regular sensory information is processed and analyzed to a greater extent, which contributes to creativity, intuition, sensing implications and attention to detail, but which may also cause quick over-stimulation and over-arousal. (Wikipedia:HSP)
What this all means is that the research being done on hypersensitivity ties the work of many great psychologists together. This is also where latent inhibition comes into play. Latent inhibition is the time it takes for something to be associated with something else in the mind. Such as a pedal that shocks you when you step on it; before long you would realize the pedal shocks you, but it would take two or three presses to make sure. Low latent inhibition means that connection is made more quickly, such as after so much as one press. That's a very simple example, and for the most part highly sensitive people won't even notice those connections being made. Their subconscious does however.
The ability to unconsciously or semi-consciously process environmental subtleties often contributes to an HSP seeming "gifted" or possessing a "sixth sense". (same article as above)
Unconsciously, connections are made and patterns established. They may not even be aware of those connections, but their subconscious slips little messages to them that can take many forms. Little subtle thoughts, metaphors in all shapes and sizes, as well as complex feelings are all examples of our subconscious talking to us. Dreams are a major example that are well beyond the scope of this blog, but that is a huge method through which the subconscious can communicate (as well, Freud wrote an entire book on it: link).
The mind is all about associations, patterns, and future predictions. Even walking becomes an automatic function after a while that is easily upset by one unforeseen little change, which we've all found out when we trip over the tiniest step in our path that we didn't notice (this is why "watch your step" signs are needed). Our subconscious is always analyzing and predicting the future, and combine that with low latent inhibition, you have someone who appears to be psychic, and even they don't know how they do it.
As far as processing information our surroundings 'deeply' comes into play, we much look at a phenomenon called "change blindness". Many, many stage performers take advantage of this. Please watch this video:
(to see just how far change blindness can be pushed, see this)
There simply is too much information entering our mind at one single instant to be aware of it all. Our brains would break down, and we would be unable to function as we would have no idea what is important to pay attention to. So our minds take what is important and leave off the rest: we are 'unaware' of it. This happens to us every day, all the time. You don't even notice your own breathing most of the time, unless something directs your attention to it. However, a highly sensitive person is more inclined to be aware of his or her surroundings, if even unconsciously. That is another consequence of low latent inhibition, more things are considered "important" to the mind. This is also where being overloaded in crowds originates from. So many things come into the mind that are considered important and deserving of attention that it drives the mind crazy. Metaphors of shields and protection bubbles may be used to protect the mind, but these techniques only treat the symptoms of the problem and not the problem in itself.
So, to summarize, the genetic component of a highly sensitive person gives them increased sensitivity to changes (stimuli), and an increased ability to form connections and patterns about their environment, which includes the people in it. This unconscious awareness of their surroundings gives them an amazing intuitive grasp of their environment and the people they encounter and have relationships with.
However, not all sensitive people are born; a great many are made.
The Empathic Factory
This is not the only cause, but it is one of the biggest. It's tough to find any real dictionary or encyclopedia definitions or discussions about this topic. However, there is a process to it. Hypersensitivity engendered out of abuse is a survival mechanism. It is a skill refined through necessity. The victim in this case becomes aware of all the tiniest hints and cues that the abuser is escalating or is close to becoming violent or abusive, and this gives them time to emotionally prepare. This process may be done consciously, or most likely, unconsciously. This skill cannot exactly be turned off, and is used on everyone, thus giving the victim a strong intuitive grasp on the emotional states of other people.
Body language and microexpressions are two developing fields in psychology which are being used to essentially read the minds of people. Unconscious body language is almost universal, and according to recent research, there are seven universal emotional expressions we display. Thus, over time, a person will recognize when those expressions or body movements appear, and associate that with a rising anger level or a high chance for abuse to begin. Over time, the person gets very adept at understanding those subtle changes and movements, and since they are universal, that intuitive awareness allows them to read not just their abuser, but everyone else in their life. One example of this is quite interesting. For someone who was physically abused, for a while afterwards they may have a very strong automatic fear of raised fists. The setting could be friendly and relaxed, but as soon as someone raises a fist, even for a fist pump or a bro-fist, the victim of abuse immediately shrinks down and is overcome with fear.
However, to say that only abuse or only genetics creates highly sensitive people is to look through a very narrow perspective. More than likely, all of these factors come into play. If we just look at low latent inhibition, an increased ability to connect ideas lends itself very well to an intuitive understanding of body language. Abuse could also be the environmental trigger for already sensitive people to develop into full blown hypersensitivity, such as some genetic traits require triggers to begin to show symptoms. All these ideas are just pieces to a large puzzle, and these by no means are all the pieces.
The Empathic Mechanism
Empathy in itself is a rather complex process. The most basic definition is for one to "put themselves in another's shoes" and to feel what the other would feel in that situation. To empathize with someone is to truly understand how they feel, even if you say or do nothing. It's that simple. Most of the time, it's an unconscious process. We don't need to explicitly create a mental situation in which we are feeling what the other person feels, we simply see them and relate to them. Such as a friend falling down and scraping their knee; you don't need to mentally reconstruct a memory where you fell down and scraped your knee, you simply see the pain that person feels and relate to it because you've felt it before. That is empathy.
Breaking it down requires several different approaches. The first is an interesting find in the field of neurology. There is a machine called an fMRI which magnetically measures blood flow in the brain. Under these machines, it has been found that when people empathize with others, the same areas of the brain activate. Thus the term "mirror neuron" because our nervous system actually mirrors the other person. Many discoveries like this have been made over the years, including that running and simply thinking of running cause the same reactions in our bodies and muscles. We, and many animals, biologically imitate others at a very deep level. This is the biological approach to empathy: observing others experiencing emotion causes our bodies to react and feel the same emotion.
A second approach is a more psychological and cognitive approach. Stored within our minds is a vast movie of everything we've ever done, said, thought, and experienced. We carry around a lifetime of experiences. We also tend to remember what we felt and how we felt more than specific details about the past. The mind is also very good at picking apart details and connections between ideas. So after enough experiences with pain, anger, sorrow and joy, we tend to know what makes us feel that and how it feels. When we observe another person experiencing that emotion, we automatically connect our past experiences, and compare. We figure out what they're feeling based on our own past experiences. And to take one step further, we are fully capable of breaking down ideas into smaller components so our experiences are quite simply mental building blocks. Using those building blocks we are able to, with relative accuracy, reconstruct what another person is going through in our minds and feel that ourselves. Of course, most of this happens automatically and unconsciously. You don't even notice it happening. It's much like when someone asks you to "imagine how they feel" in a situation. You think about what they're going through, and imaginatively place yourself in that situation. Of course, you can't create a separate reality in your mind, so you draw on what you already know and have experienced in the past. It's the same process, one just happens without verbal thoughts.
A third approach is more a social psychology approach. There are roughly 40 muscles in the human face, most of which are used for expression of emotion. Some expressions last for only a few milliseconds, and show a person's genuine emotion before they consciously control their expression; these are microexpressions. Only 7 percent of a conversation is expressed in the words. Consciously and unconsciously we all read body language and see expressions, even microexpressions. Crossing arms, crossing legs, breaking eye contact, maintaining eye contact, leaning in, leaning away, tapping fingers or feet, rubbing the nose or face, twisting rings or messing with jewelry, everyone sees body language even if they don't consciously notice it. When we agree with someone or like them, we mirror their body language. When we oppose someone or disagree, we may cross our arms and lean away. These things all have unconscious meaning, and it's all nonverbal communication. Now, add in an increased awareness, an intuitive grasp of human psychology and an increased ability to recognize small details and you have what is considered an empath.
Emotional contagion is a separate topic all in itself, but I will briefly explain what it is. Emotional contagion is simply the tendency for people to feel what others are feeling. It's basically just unconscious empathy. Has anyone ever infected you with a smile or with joy? You couldn't help but feel happy around them, even if you felt down before? That is emotional contagion. If someone has ever been a "downer" or brought you down from happiness, that is also emotional contagion.
Fruits of Hypersensitivity
Obviously the biggest trait of one who is hypersensitive is an exceptionally intuitive grasp on the emotions of others. Several things come as a consequence of this and the way empaths are conditioned. First off, I will describe a very common trait among empaths, and is even included in many lists of empathic traits.
Empaths are people-pleasers, they can't help it. Teasing out a smile from a friend or loved one is as natural to them as breathing, and they will do whatever it takes to feel that smiling approval from their contemporaries. Taken to extremes, this trait leads to fatal self-compromise, as the Empath loses her integrity in her attempts to win acceptance and love from parents, friends, spouses, and children. (Identifying as an Empath)
Having an intuitive grasp on the psychology of others lends itself easily to one becoming distracted and outwardly focused, as opposed to a healthy balance of outward and inward focus. This may be a coping mechanism to deal with an internal issue or problem that one doesn't want to touch. This easily becomes what is known as "altruism to a fault", where the person places their self-esteem and self-worth on helping other people. They give and give until there's nothing left. This is the type of person that smiles and laughs and throws parties, but cries herself to sleep at night. This is the white knight stereotype, the person who lives to help other people.
A second problem many hypersensitive people experience is a feeling of being overwhelmed in crowds. There are many ways to look at this issue, but I'll just focus on two: the first is a social psychology approach, the other is a more internal psychotherapy approach. The first approach is similar to what was described earlier: a feeling of being overwhelmed because of all the incoming information. A highly sensitive person with an increased awareness may be seeing so much and taking in so many details that it puts too much stress on their system. Their unconscious is feeding them so many details it deems 'important', the emotional states of others, that it overloads them. A good example is a dog or a horse. This may not seem very relevant, but bear with me here. For a scent dog or a horse that pulls a carriage, you have to actually get them adjusted to a city. The first time they experience a big city, there is so much going on that it causes them to get overly anxious and in some cases, deathly fearful. Over time, they learn to ignore the many many sights and sounds, but for that first time, they just get overloaded. It's way too much new stuff at once. Since humans are much more complex though, and we have nobody forcing us to deal with being overloaded, we may never learn how to filter out the useless information through experience. We may also develop a fear of that situation, and refuse to get the experience that would help. This leads nicely into the next topic, and you'll see why in a second.
The second approach deals more with what made the person sensitive in the first place. Abuse and problems growing up have the tendency to leave people with anxiety disorders. A very common anxiety disorder is agoraphobia. Agoraphobia is not just a fear of open spaces, or a fear of the outside, but also a fear of crowds and public places with lots of people. This can cause what is known as a panic attack. Panic attacks are terrifying experiences, and among the symptoms are feelings of suffocating, extreme anxiety and fear. Often those who experience a panic attack will develop fears of the situation where it occurred.
Once someone has had a panic attack, he or she may develop irrational fears, called phobias, about the situations they are in during the attacks and begin to avoid them. That, in turn, may reach the point where the mere idea of doing things that preceded the first panic attack triggers terror or dread of future panic attacks, resulting in the individual with panic disorder being unable to drive or even step out of the house. If this occurs, the person is considered to have panic disorder with agoraphobia. (emedicinehealth: Panic Attack)
Now this may be an extreme example, but it sounds familiar. Those who experienced overwhelming feelings in crowds may in turn, avoid crowds. Eventually they will feel inundated because of the building anxiety that occurs when they are in crowds. Quite a vicious circle.
Psychologically and genetically, an empath is one who is more sensitive to their environment and the details therein. But the key here, is that this is not all an empath is. Reality is inclusive, not exclusive. There are many things science has yet to uncover and examine. This is the scientific perspective, and all perspectives are equally valid. And no matter what perspective you take, empathy is a beautiful thing. A man sitting on the bus, his head hanging downward, his hands loosely sitting in his lap, looks up to see someone looking back at him. The stranger gives the man a soft smile. That is empathy.