question: Why and how do we physically feel our hearts when we have strong emotions? Like in the phrase "my heart skipped a beat" or "my heart dropped" for example.
comment: your body doesn't take chances. So when ever any kind of stress comes along (Physical or emotional) it does the same thing: gets ready to act. you feel it change suddenly because that's exactly what happens. It immediately changes how fast and strong its beating to supply your body with more energy to deal with whatever might happen. You interpret this sensation as skipping a beat, but its just an illusion. When the change is gradual like with exercise you never really notice it. Its when it changes abruptly that its jarring.
passages: It has long been recognized that emotional episodes are partly constituted by physiological responses. Early work done linking emotions to psychophysiology started with research on mapping consistent autonomic nervous system (ANS) responses to discrete emotional states. For example, anger might be constituted by a certain set of physiological responses, such as increased cardiac output and high diastolic blood pressure, which would allow us to better understand patterns and predict emotional responses. Some studies were able to detect consistent patterns of ANS responses that corresponded to specific emotions under certain contexts, like an early study by Paul Ekman and colleagues in 1983 "Emotion-specific activity in the autonomic nervous system was generated by constructing facial prototypes of emotion muscle by muscle and by reliving past emotional experiences. The autonomic activity produced distinguished not only between positive and negative emotions, but also among negative emotions". 
   Physiological responses to emotion originate in the central nervous system, the autonomic nervous system, and the endocrine system. Some of the responses include: heart rate, sweating, rate and depth of respiration, and electrical activity in the brain. Many researchers have attempted to find a connection between specific emotions and a corresponding pattern of physiological responses, although it is said that these attempts have rendered unsuccessful conclusions.
  
  Section::::Theories of emotional response.
   For example, the emotion of love is proposed to be the expression of paleocircuits of the mammalian brain (specifically, modules of the cingulate gyrus) which facilitate the care, feeding, and grooming of offspring. Paleocircuits are neural platforms for bodily expression configured before the advent of cortical circuits for speech. They consist of pre-configured pathways or networks of nerve cells in the forebrain, brain stem and spinal cord.
   The Cannon-Bard theory, which was conceptualized by Walter Cannon and Phillip Bard, suggests that emotions and their corresponding physiological responses are experienced simultaneously. Using the previous example, when someone sees the car coming toward them in their lane, their heart starts to race and they feel afraid at the same time.
  
  Section::::Theories of emotional response.:Schachter-Singer theory of emotion.
   Following the influence of René Descartes and his ideas regarding the split between body and mind, in 1884 William James proposed the theory that it is not that the human body acts in response to our emotional state, as common sense might suggest, but rather, we interpret our emotions on the basis of our already present bodily state. In the words of James, "we feel sad because we cry, angry because we strike, afraid because we tremble, and neither we cry, strike, nor tremble because we are sorry, angry, or fearful, as the case may be." James believed it was particular and distinct physical patterns that map onto specific experienced emotions. Contemporaneously, psychologist Carl Lange arrived at the same conclusion about the experience of emotions. Thus, the idea that felt emotion is the result of perceiving specific patterns of bodily responses is called the James-Lange theory of emotion.
   Cannon also emphasized that visceral responses occur when experiencing many different emotions, and in the absence of emotion. For example, the same visceral responses such as increased heart rate, sweating, widening of the pupils, and the discharge of adrenaline can be associated with the experience of fear or anger. However, they are also connected to conditions such as fever, feeling cold, and having difficulty breathing. Therefore, the physical emotional responses that had so far been documented are too general to be linked to a specific emotion.
   The significant theories of emotion can be divided into three primary categories: physiological, neurological, and cognitive. Physiological theories imply that activity within the body can be accountable for emotions. Neurological theories suggest that activity within the brain leads to emotional responses. Lastly, cognitive theories reason that thoughts and other mental activity have a vital role in the stimulation of emotions. Common-sense suggests that people first become consciously aware of their emotions and that the physiological responses follow shortly after. Below are a few well-known theories which contradict this common-sense theory:
  
  Section::::Theories of emotional response.:James-Lange theory of emotion.
   Another neurological approach proposed by Bud Craig in 2003 distinguishes two classes of emotion: "classical" emotions such as love, anger and fear that are evoked by environmental stimuli, and "homeostatic emotions" – attention-demanding feelings evoked by body states, such as pain, hunger and fatigue, that motivate behavior (withdrawal, eating or resting in these examples) aimed at maintaining the body's internal milieu at its ideal state.
   Emotions, as defined by Damasio, are changes in both body and brain states in response to stimuli. Physiological changes (such as muscle tone, heart rate, endocrine activity, posture, facial expression, and so forth) occur in the body and are relayed to the brain where they are transformed into an emotion that tells the individual something about the stimulus that they have encountered. Over time, emotions and their corresponding bodily changes, which are called "somatic markers", become associated with particular situations and their past outcomes.
   Stanley Schachter and Jerome Singer proposed a theory also known as the two-factor theory of emotion, which implies emotion have two factors: physical arousal and cognitive label. This suggests that the physiological activity occurs first, then it must cognitively be distinguished as the cause of the arousal and labeled as an emotion. Using the example of someone seeing a car coming towards them in their lane, their heart would start to race and they would identify that they must be afraid if their heart is racing, and from there they would begin to feel fear.
  
  Section::::Gender differences.
   Some theories of emotion take the stance that emotional expression is more flexible, and that there is a cognitive component to emotion. These theories account for the malleability in emotion by proposing that humans appraise situations and, depending on the result of their appraisal, different emotions and the corresponding expressions of emotion are triggered. The tendency to appraise certain situations as one emotion or another can vary by person and culture; however, appraisal models still maintain that there are basic responses that are specific and consistent to each emotion that humans feel.
   BULLET::::- Creased forehead
  
  BULLET::::- Raised eyebrows
  
  BULLET::::- Wide eyes
  
  BULLET::::- Physiological responses
  
  BULLET::::- muscle tension
  
  BULLET::::- elevated heart rate
  
  BULLET::::- sweating
  
  BULLET::::- nausea
  
  BULLET::::- shaking
  
  BULLET::::- gastrointestinal distress
  
  BULLET::::- Observable behavior
  
  BULLET::::- averted gaze
  
  BULLET::::- avoidance
  
  BULLET::::- excitement
  
  BULLET::::- fidgeting
  
  BULLET::::- gasping
  
  Section::::Early theories of emotion.
   In mammals, emotional responses are processed in a part of the brain called the limbic system which lies in the cerebral cortex. The main components of the limbic system are the amygdala, orbitofrontal cortex, thalamus and the sensory cortex.
  
  The amygdala is an almond shaped area which is placed such that it can communicate with all other cortices within the limbic system. The primary affective conditioning of the system occurs within the amygdala. That is, the association between a stimulus and its emotional consequence takes place in this region.
   This is where the ability to condition emotional reactions comes into play. Biological organisms associate innate emotional stimuli with other stimuli they encounter in the world and thus give them an emotional significance when needed. These evaluations can be monitored to operate at very specific times, specific places or when accompanied by other specific stimuli.
  
  There is another reason why these observations are so significant and that is the creation of artificial systems. These systems do not evolve over time but are designed with certain abilities from the start. Thus, their adaptability must be built-in.
  
  Section::::Computational model.
   Section::::Modes of perception.
  
  Emotions can be perceived through visual, auditory, olfactory, and physiological sensory processes. Nonverbal actions can provide social partners with information about subjective and emotional states. This nonverbal information is believed to hold special importance and sensory systems and certain brain regions are suspected to specialize in decoding emotional information for rapid and efficient processing.
  
  Section::::Modes of perception.:Visual.
   The essence of James's proposal was simple. It was premised on the fact that emotions are often accompanied by bodily responses (racing heart, tight stomach, sweaty palms, tense muscles, and so on; sympathetic nervous system) and that we can sense what is going on inside our body much the same as we can sense what is going on in the outside world. According to James, emotions feel different from other states of mind because they have these bodily responses that give rise to internal sensations, and different emotions feel different from one another because they are accompanied by different bodily responses and sensations. For example, when we see James's bear, we run away. During this act of escape, the body goes through a physiological upheaval: blood pressure rises, heart rate increases, pupils dilate, palms sweat, muscles contract in certain ways (evolutionary, innate defense mechanisms). Other kinds of emotional situations will result in different bodily upheavals. In each case, the physiological responses return to the brain in the form of bodily sensations, and the unique pattern of sensory feedback gives each emotion its unique quality. Fear feels different from anger or love because it has a different physiological signature (the parasympathetic nervous system for love). The mental aspect of emotion, the feeling, is a slave to its physiology, not vice versa: we do not tremble because we are afraid or cry because we feel sad; we are afraid because we tremble and are sad because we cry.
   According to James-Lange theory, the conscious experience of emotion occurs after the cortex receives signals about changes in physiological state. Researchers argued that feelings are preceded by certain physiological changes. Thus, when we see a venomous snake, we feel fear, because our cortex has received signals about our racing heart, knocking knees, etc. Damasio distinguishes primary and secondary emotions. Both involve changes in bodily states, but the secondary emotions are evoked by thoughts. Recent empirical studies support non-cognitive theories of nature of emotions. It was proven that we can easily evoke our emotions by something as simple as changing facial expression (e.g., smile brings on a feeling of happiness).
   By the late 1800s, many high-quality contributions had been made to the theory of emotion by psychologists and scientists such as Wilhelm Wundt, George Stout, William McDougall, William James, and George Herbert Mead. William James preferred to focus on the physiological aspects of emotional response, though he did not disregard the perceptual or cognitive components. William McDougall thought of emotion as the articulation of a natural response built on instinct. Other psychologists reasoned that although gestures express emotion, this is not the entirety of their function. Wundt analyzed that emotion portrays both expression and communication.
   Lazarus stressed that the quality and intensity of emotions are controlled through cognitive processes. These processes underline coping strategies that form the emotional reaction by altering the relationship between the person and the environment.
  
  George Mandler provided an extensive theoretical and empirical discussion of emotion as influenced by cognition, consciousness, and the autonomic nervous system in two books ("Mind and Emotion", 1975, and "Mind and Body: Psychology of Emotion and Stress", 1984)
   Phillip Bard contributed to the theory with his work on animals. Bard found that sensory, motor, and physiological information all had to pass through the diencephalon (particularly the thalamus), before being subjected to any further processing. Therefore, Cannon also argued that it was not anatomically possible for sensory events to trigger a physiological response prior to triggering conscious awareness and emotional stimuli had to trigger both physiological and experiential aspects of emotion simultaneously.
  
  Section::::Classification.:Somatic theories.:Two-factor theory.
   In support of the James-Lange theory of emotion, Silvan Tomkins proposed the facial feedback hypothesis in 1963; he suggested that facial expressions actually trigger the experience of emotions and not the other way around. This theory was tested in 1974 by James Laird in an experiment where Laird asked participants to hold a pencil either between their teeth (artificially producing a smile) or between their upper lip and their nose (artificially producing a frown) and then rate cartoons. Laird found that these cartoons were rated as being funnier by those participants holding a pencil in between their teeth. In addition, Paul Ekman recorded extensive physiological data while participants posed his basic emotional facial expressions and found that heart rate raised for sadness, fear, and anger yet did not change at al for happiness, surprise, or disgust, and skin temperature raised when participants posed anger but not other emotions. While contemporary psychologists still agree with the James-Lange theory of emotion, human subjective emotion is complex and physical reactions or antecedents do not fully explain the subjective emotional experience.
   A subject's blood volume pulse (BVP) can be measured by a process called photoplethysmography, which produces a graph indicating blood flow through the extremities. The peaks of the waves indicate a cardiac cycle where the heart has pumped blood to the extremities. If the subject experiences fear or is startled, their heart usually 'jumps' and beats quickly for some time, causing the amplitude of the cardiac cycle to increase. This can clearly be seen on a photoplethysmograph when the distance between the trough and the peak of the wave has decreased. As the subject calms down, and as the body's inner core expands, allowing more blood to flow back to the extremities, the cycle will return to normal.
   To further support the assertion that emotional expression results from action of subcortical centers, Cannon and Britton performed further experimental research with cats. Cats were decorticated, and after a period of recovery they spontaneously displayed the behaviours characteristic of intense fury. This response, referred to as sham rage, continued to be displayed after ablation of all brain regions anterior to the diencephalon. However, once the lower posterior portion of the thalamic region was removed, the display of sham rage by the cats subsided. Based on this finding, it was concluded that the thalamus was a region from which, in the absence of cortical control, impulses are discharged which evoke an extreme degree of "emotional" activity, both muscular and visceral.
   BULLET::::- Another hormone found in the direct response from emotion is adrenocorticotropic hormone (ACTH) secreted in response to fearful stimuli. ACTH is secreted by the posterior pituitary in response to fear and plays a role in the facilitation or inhibition of behaviors and actions to follow. In most cases, a high ACTH secretion will lead to the inhibition of actions that would produce the same fearful response that just occurred.
   Three more specific types of emotion work are cognitive, bodily, and expressive. Cognitive changes images, bodily changes physical aspects, and expressive changes gestures. A person who is sad uses expressive emotion work to lift their spirits by trying to smile. A person who is stressed uses bodily emotion work by trying to breathe slower in order to lower stress levels. Emotion work allows individuals to change their feelings to suit the current situation.
  