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NVC can be communicated through gesture and touch (Haptic communication), by body language or posture, by facial expression and eye contact. NVC can be communicated through object communication such as clothing, hairstyles or even architecture, symbols and infographics. Speech contains nonverbal elements known as paralanguage, including voice quality, emotion and speaking style, as well as prosodic features such as rhythm, intonation and stress. Likewise, written texts have nonverbal elements such as handwriting style, spatial arrangement of words, or the use of emoticons.
However, much of the study of nonverbal communication has focused on face-to-face interaction, where it can be classified into three principal areas: environmental conditions where communication takes place, the physical characteristics of the communicators, and behaviors of communicators during interaction.
Verbal vs oral communication
Scholars in this field usually use a strict sense of the term "verbal", meaning "of or concerned with words," and do not use "verbal communication" as a synonym for oral or spoken communication. Thus, vocal sounds that are not considered to be words, such as a grunt, or singing a wordless note, are nonverbal. Sign languages and writing are generally understood as forms of verbal communication, as both make use of words — although like speech, both may contain paralinguistic elements and often occur alongside nonverbal messages. Nonverbal communication can occur through any sensory channel — sight, sound, smell, touch or taste. NVC is important as:
"When we speak (or listen), our attention is focused on words rather than body language. But our judgement includes both. An audience is simultaneously processing both verbal and nonverbal cues. Body movements are not usually positive or negative in and of themselves; rather, the situation and the message will determine the appraisal." (Givens, 2000, p. 4)
The first scientific study of nonverbal communication was Charles Darwin's book The Expression of the Emotions in Man and Animals (1872). He argued that all mammals show emotion reliably in their faces. Studies now range across a number of fields, including , linguistics, semiotics and social psychology.
While much nonverbal communication is based on arbitrary symbols, which differ from culture to culture, a large proportion is also to some extent iconic and may be universally understood. Paul Ekman's influential 1960s studies of facial expression determined that expressions of anger, disgust, fear, joy, sadness and surprise are universal.
Clothing and bodily characteristics
Elements such as physique, height, weight, hair, skin color, gender, odors, and clothing send nonverbal messages during interaction. For example, a study  was made in Vienna, Austria, of the clothing worn by women attending discotheques. It was found for certain groups of women (especially women which were in town without their partners) that motivation for sex, and levels of sexual hormones, were correlated with aspects of the clothing, especially the amount of skin displayed, and the presence of sheer clothing, e.g. at the arms. Thus, to some degree, clothing sent signals about interest in courtship.
Research into height has generally found that taller people are perceived as being more impressive. Melamed & Bozionelos (1992) studied a sample of managers in the UK and found that height was a key factor affecting who was promoted. Often people try to make themselves taller, for example, standing on a platform, when they want to make more of an impact with their speaking.
Environmental factors such as furniture, architectural style, interior decorating, lighting conditions, colors, temperature, noise, and music affect the behavior of communicators during interaction. The furniture itself can be seen as a nonverbal message
Proxemics is the study of how people use and perceive the physical space around them. The space between the sender and the receiver of a message influences the way the message is interpreted.
The perception and use of space varies significantly across cultures and different settings within cultures. Space in nonverbal communication may be divided into four main categories: intimate, social, personal, and public space.(Scott Mclean, 1969) The distance between communicators will also depend on sex, status, and social role.
Proxemics was first developed by Edward T. Hall during the 1950s and 60s. Hall's studies were inspired by earlier studies of how animals demonstrate territoriality. The term territoriality is still used in the study of proxemics to explain human behavior regarding personal space. Hargie & Dickson (2004, p. 69) identify 4 such territories:
- Primary territory: this refers to an area that is associated with someone who has exclusive use of it. For example, a house that others cannot enter without the owner’s permission.
- Secondary territory: unlike the previous type, there is no “right” to occupancy, but people may still feel some degree of ownership of a particular space. For example, someone may sit in the same seat on train every day and feel aggrieved if someone else sits there.
- Public territory: this refers to an area that is available to all, but only for a set period, such as a parking space or a seat in a library. Although people have only a limited claim over that space, they often exceed that claim. For example, it was found that people take longer to leave a parking space when someone is waiting to take that space.
- Interaction territory: this is space created by others when they are interacting. For example, when a group is talking to each other on a footpath, others will walk around the group rather than disturb it.
Chronemics is the study of the use of time in nonverbal communication. The way we perceive time, structure our time and react to time is a powerful communication tool, and helps set the stage for communication. Time perceptions include punctuality and willingness to wait, the speed of speech and how long people are willing to listen. The timing and frequency of an action as well as the tempo and rhythm of communications within an interaction contributes to the interpretation of nonverbal messages. Gudykunst & Ting-Toomey (1988) identified 2 dominant time patterns:
- Monochronic time schedule (M-time): Time is seen as being very important and it is characterized by a linear pattern where the emphasis is on the use of time schedules and appointments. Time is viewed as something that can be controlled or wasted by individuals, and people tend to do one thing at a time. The M-pattern is typically found in North America and Northern Europe.
- Polychronic time schedule (P-time): Personal involvement is more important than schedules where the emphasis lies on personal relationships rather than keeping appointments on time. This is the usual pattern that is typically found in Latin America and the Middle East.
Movement and body position
Kinesics is the study of body movements, facial expressions, and gestures. It was developed by anthropologist Ray L. Birdwhistell in the 1950s. Kinesic behaviors include mutual gaze, smiling, facial warmth or pleasantness, childlike behaviors, direct body orientation, and the like. Birdwhistell proposed the term kineme to describe a minimal unit of visual expression, in analogy to a phoneme which is a minimal unit of sound.
Posture can be used to determine a participant’s degree of attention or involvement, the difference in status between communicators, and the level of fondness a person has for the other communicator. Studies investigating the impact of posture on interpersonal relationships suggest that mirror-image congruent postures, where one person’s left side is parallel to the other’s right side, leads to favorable perception of communicators and positive speech; a person who displays a forward lean or a decrease in a backwards lean also signify positive sentiment during communication. Posture is understood through such indicators as direction of lean, body orientation, arm position, and body openness.
A gesture is a non-vocal bodily movement intended to express meaning. They may be articulated with the hands, arms or body, and also include movements of the head, face and eyes, such as winking, nodding, or rolling ones' eyes. The boundary between language and gesture, or verbal and nonverbal communication, can be hard to identify.
According to Ottenheimer (2007), psychologists Paul Ekman and Wallace Friesen suggested that gestures could be categorised into five types: emblems, illustrators, affect displays, regulators, and adaptors.
- Emblems are gestures with direct verbal translations, such as a goodbye wave;
- illustrators are gestures that depict what is said verbally, such as turning an imaginary steering wheel while talking about driving;
- an affect display is a gesture that conveys emotions, like a smile;
- regulators are gestures that control interaction;
- and finally, an adaptor is a gesture that facilitates the release of bodily tension, such as quickly moving one's leg.
Gestures can also be categorised as either speech-independent or speech-related. Speech-independent gestures are dependent upon culturally accepted interpretation and have a direct verbal translation. A wave hello or a peace sign are examples of speech-independent gestures. Speech related gestures are used in parallel with verbal speech; this form of nonverbal communication is used to emphasize the message that is being communicated. Speech related gestures are intended to provide supplemental information to a verbal message such as pointing to an object of discussion.
Gestures such as Mudra (Sanskrit) encode sophisticated information accessible to initiates that are privy to the subtlety of elements encoded in their tradition.
Haptics is the study of touching as nonverbal communication. Touches that can be defined as communication include handshakes, holding hands, kissing (cheek, lips, hand), back slapping, high fives, a pat on the shoulder, and brushing an arm. Touching of oneself may include licking, picking, holding, and scratching. These behaviors are referred to as "adaptor" and may send messages that reveal the intentions or feelings of a communicator. The meaning conveyed from touch is highly dependent upon the context of the situation, the relationship between communicators, and the manner of touch.
The study of the role of [eye contact]] in nonverbal communication is sometimes referred to as "oculesics". Eye contact can indicate interest, attention, and involvement. Gaze comprises the actions of looking while talking, looking while listening, amount of gaze, and frequency of glances, patterns of fixation, pupil dilation, and blink rate.
Manual communication involves the use of the hand to send messages.
Paralanguage (sometimes called vocalics) is the study of nonverbal cues of the voice. Various acoustic properties of speech such as tone, pitch and accent, collectively known as prosody, can all give off nonverbal cues. Paralanguage may change the meaning of words.
The linguist George L. Trager developed a classification system which consists of the voice set, voice qualities, and vocalization.
- The voice set is the context in which the speaker is speaking. This can include the situation, gender, mood, age and a person's culture.
- The voice qualities are volume, pitch, tempo, rhythm, articulation, resonance, nasality, and accent. They give each individual a unique "voice print".
- Vocalization consists of three subsections: characterizers, qualifiers and segregates. Characterizers are emotions expressed while speaking, such as laughing, crying, and yawning. A voice qualifier is the style of delivering a message - for example, yelling "Hey stop that!", as opposed to whispering "Hey stop that". Vocal segregates such as "uh-huh" notify the speaker that the listener is listening.
Functions of nonverbal communication
Argyle (1970)  put forward the hypothesis that whereas spoken language is normally used for communicating information about events external to the speakers, non-verbal codes are used to establish and maintain interpersonal relationships. It is considered more polite or nicer to communicate attitudes towards others non-verbally rather than verbally, for instance in order to avoid embarrassing situations .
Argyle (1988) concluded there are five primary functions of nonverbal bodily behavior in human communication:
- Express emotions
- Express interpersonal attitudes
- To accompany speech in managing the cues of interaction between speakers and listeners
- Self-presentation of one’s personality
- Rituals (greetings)
Nonverbal communication makes it easier to lie without being revealed. This is the conclusion of a study where people watched made-up interviews of persons accused of having stolen a wallet. The interviewees lied in about 50 % of the cases. People had access to either written transcripts of the interviews, or audio tape recordings, or video recordings. The more clues that were available to those watching, the larger was the trend that interviewees who actually lied were judged to be truthful. That is, people that are clever at lying can use voice tone and face expression to give the impression that they are truthful 
The relation between verbal and nonverbal communication
The relative importance of verbal and nonverbal communication
An interesting question is: When two people are communicating face-to-face, how much of the meaning is communicated verbally, and how much is communicated non-verbally? This was investigated by Albert Mehrabian and reported in two papers , . The latter paper concluded: "It is suggested that the combined effect of simultaneous verbal, vocal, and facial attitude communications is a weighted sum of their independent effects - with coefficients of .07, .38, and .55, respectively." This "rule" that clues form spoken words, from the voice tone, and from the facial expression, contribute 7 %, 38 %, and 55 % respectively to the total meaning, is widely cited. It is presented on all types of popular courses with statements like "scientists have found out that . . . ". In reality, however, it is extremely weakly founded. First, it is based on the judgment of the meaning of single taperecorded words, i.e. a very artificial context. Second, the figures are obtained by combining results from two different studies which maybe cannot be combined. Third, it relates only to the communication of positive versus negative emotions. Fourth, it relates only to women, as men did not participate in the study.
Since then, other studies have analysed the relative contribution of verbal and nonverbal signals under more naturalistic situations. Argyle  , using video tapes shown to the subjects, analysed the communication of submissive/dominant attitude and found that non-verbal cues had 4.3 times the effect of verbal cues. The most important effect was that body posture communicated superior status in a very efficient way. On the other hand, a study by Hsee et al.  had subjects judge a person on the dimension happy/sad and found that words spoken with minimal variation in intonation had an impact about 4 times larger than face expressions seen in a film without sound. Thus, the relative importance of spoken words and facial expressions may be very different in studies using different set-ups.
Interaction of verbal and nonverbal communication
When communicating, nonverbal messages can interact with verbal messages in six ways: repeating, conflicting, complementing, substituting, regulating and accenting/moderating.
"Repeating" consists of using gestures to strengthen a verbal message, such as pointing to the object of discussion.
Verbal and nonverbal messages within the same interaction can sometimes send opposing or conflicting messages. A person verbally expressing a statement of truth while simultaneously fidgeting or avoiding eye contact may convey a mixed message to the receiver in the interaction. Conflicting messages may occur for a variety of reasons often stemming from feelings of uncertainty, ambivalence, or frustration. When mixed messages occur, nonverbal communication becomes the primary tool people use to attain additional information to clarify the situation; great attention is placed on bodily movements and positioning when people perceive mixed messages during interactions.
Accurate interpretation of messages is made easier when nonverbal and verbal communication complement each other. Nonverbal cues can be used to elaborate on verbal messages to reinforce the information sent when trying to achieve communicative goals; messages have been shown to be remembered better when nonverbal signals affirm the verbal exchange.
Nonverbal behavior is sometimes used as the sole channel for communication of a message. People learn to identify facial expressions, body movements, and body positioning as corresponding with specific feelings and intentions. Nonverbal signals can be used without verbal communication to convey messages; when nonverbal behavior does not effectively communicate a message, verbal methods are used to enhance understanding.
Nonverbal behavior also regulates our conversations. For example, touching someone's arm can signal that you want to talk next or interrupt.
Nonverbal signals are used to alter the interpretation of verbal messages. Touch, voice pitch, and gestures are some of the tools people use to accent or amplify the message that is sent; nonverbal behavior can also be used to moderate or tone down aspects of verbal messages as well. For example, a person who is verbally expressing anger may accent the verbal message by shaking a fist.
Dance and nonverbal communication
Dance is a form of nonverbal communication that requires the same underlying faculty in the brain for conceptualization, creativity and memory as does verbal language in speaking and writing. Means of self-expression, both forms have vocabulary (steps and gestures in dance), grammar (rules for putting the vocabulary together) and meaning. Dance, however, assembles (choreographs) these elements in a manner that more often resembles poetry, with its ambiguity and multiple, symbolic and elusive meanings.
Clinical studies of nonverbal communication
From 1977 to 2004, the influence of disease and drugs on receptivity of nonverbal communication was studied by teams at three separate medical schools using a similar paradigm..Researchers at the University of Pittsburgh, Yale University and Ohio State University had subjects observe gamblers at a slot machine awaiting payoffs. The amount of this payoff was read by nonverbal transmission prior to reinforcement. This technique was developed by and the studies directed by psychologist, Dr. Robert E. Miller and psychiatrist, Dr. A. James Giannini. These groups reported diminished receptive ability in heroin addicts  and phencyclidine abusers was contrasted with increased receptivity in cocaine addicts. Men with major depression manifested signicantly decreased ability to read nonverbal cues when compared with euthymic men.
Obese women and women with premenstrual syndrome were found to also possess diminished abilities to read these cues. In contradistinction, men with bipolar disorder possessed increased abilities.. A woman with total paralysis of the nerves of facial expression was found unable to transmit or receive any nonverbal facial cues whatsoever. . Because of the changes in levels of accuracy on the levels of nonverbal receptivity. The members of the research team hypothesized a biochemical site in the brain which was operative for reception of nonverbal cues. Because certain drugs enhanced ability while others diminished it, the neurotransmitters dopamine an d endorphin were considered to be likely etiological candidate. Based on the available data, however, the primary cause and primary effect could not be sorted out on the basis of the paradigm employed.
A byproduct of the work of the Pittsburgh/Yale/ Ohio State team was an investigation of the role of nonverbal facial cues in heterosexual nondate rape. Males who were serial rapists of adult women were studied for nonverbal receptive abilities. Their scores were the highest of any subgroup. Rape victims were next tested. It was reported that women who had been raped on at least two occasions by different perpetrators had a highly significant impairment in their abilities to read these cues in either male or female senders.  These results were troubling, indicating a predator-prey model. The authors did note that whatever the nature of these preliminary findings the responsibility of the rapist was in no manner or level,diminished.
The final target of study for this group was the medical students they taught. Medical students at Ohio State University, Ohio University and Northest Ohio Medical College were invited to serve as subjects. Students indicating a preference for the specialties of family practice, psychiatry, pediatrics and obstetrics-gynecology achieved significantly higher levels of accuracy than those students who planned to train as surgeons, radiologists, or pathologists. Internal medicine and plastic surgery candidates scored at levels near the mean.
Difficulties with nonverbal communication
Measurements of the ability to communicate nonverbally and the capacity to feel empathy have shown that the two abilities are independent of each other .
For people who have relatively large difficulties with nonverbal communication, this can be rather handicapping, especially in interpersonal relationships. There exist resources that are directly aimed at such people and attempt to explain in detail that which is obvious to a large percentage of the population. A specific group of persons that have special difficulties are those with autism spectrum disorders, including Asperger Syndrome.
- Albert Mehrabian - for an explanation of the often quoted 7%-38%-55% rule of nonverbal communication
- Behavioral communication
- Body language
- Embodied language processing
- Gestural language
- Intercultural competence
- Joint attention
- Metacommunicative competence
- Neuro-linguistic programming
- Meaning (non-linguistic)
- Movement pattern analysis
- Nonverbal ability
- Nonverbal intimacy
- Nonverbal learning
- Nonverbal meaning
- Nonverbal reinforcement
- Types of gestures
- Unconscious communication
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- "Credibility, Respect, and Power: Sending the Right Nonverbal Signals" by Debra Stein
- Nonverbal Library The largest library on nonverbal communication on internet with more than 500 free available articles on this topic.
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