Source–message–channel–receiver model of communication
The source–message–channel–receiver model is a linear transmission model of communication. It is also referred to as the sender–message–channel–receiver model, the SMCR model, and Berlo's model. It was first published by David Berlo in his 1960 book The Process of Communication. It contains a detailed discussion of the four main components of communication: source, message, channel, and receiver. Source and receiver are usually distinct persons but can also be groups and, in some cases, the same entity acts both as source and receiver. Berlo discusses both verbal and non-verbal communication and sees all forms of communication as attempts by the source to influence the behavior of the receiver. The source tries to achieve this by formulating a communicative intention and encoding it in the form of a message. The message is sent to the receiver using a channel and has to be decoded so they can understand it and react to it. The efficiency or fidelity of communication is defined by the degree to which the reaction of the receiver matches the purpose motivating the source.
Each of the four main components has several key attributes. Source and receiver share the same four attributes: communication skills, attitudes, knowledge, and social-cultural system. Communication skills determine how good the communicators are at encoding and decoding messages. Attitudes affect whether they like or dislike the topic and each other. Knowledge includes how well they understand the topic. The social-cultural system encompasses their social and cultural background.
The attributes of the message are code, content, and treatment as well as elements and structure. A code is a sign system like a language. The content is the information expressed in the message. The treatment consists of the source's choices on the level of code and content when formulating the message. Each of these attributes can be analyzed based on the elements it uses and based on how they are combined to form a structure.
The remaining main component is the channel. It is the medium and process of how the message is transmitted. Berlo discusses it primarily in terms of the five senses used to decode messages: seeing, hearing, touching, smelling, and tasting. Depending on the message, some channels are more useful than others. It is often advantageous to use several channels simultaneously.
The SMCR model has been applied to various fields, such as mass communication, communication at the workplace, and psychology. It also influenced many subsequent communication theorists. It has been criticized for oversimplifying communication. For example, as a linear transmission model, it does not include the discussion of feedback loops found in many later models. Another common objection is that the SMCR model fails to take noise and other barriers to communication seriously and simply assumes that communication attempts are successful.
Background
published his source–message–channel–receiver model of communication in his 1960 book The Process of Communication. Some theorists also refer to it as the sender–message–channel–receiver model. Its exact formulation is usually attributed to Berlo but models with similar components were already proposed earlier, such as the Shannon–Weaver model and Schramm's model. For this reason, term SMCR model is sometimes used to refer to these models as well.Nature and purpose of communication
According to Berlo, communication is based on things that source and receiver have in common. He understands communication in a very wide sense that includes non-verbal communication like body language or the use of color in advertisements besides verbal communication in spoken or written form. In the widest sense, "anything to which people attach meanings may be and is used in communication". Berlo sees communication as a dynamic process that does not consist of a fixed sequence of events with a clearly defined beginning, middle, or end. But he acknowledges that the structure of language makes it necessary to describe communication in such a linear way.Berlo holds that the goal of all forms of communication is to influence the behavior of the audience. In this regard, he rejects the idea that other goals, like informing the receiver or entertaining them, are equally important. He argues that these distinctions are not exclusive. This means that even attempts to inform, as in the case of regular education, or to entertain, as in the case of entertainment programs on television, are attempts to influence the behavior of the audience. Berlo gives a biological argument for this position by holding that " basic purpose is to alter the relationship between our own organism and the environment".
For Berlo, communication is just one way to achieve this in relation to other people that are part of the environment: "we communicate to influence". For this reason, understanding communication involves understanding the source's goal, i.e. what reaction they intend to provoke in the audience. However, the source may not always be conscious of their reasons for communicating. For example, a writer may believe their purpose is to write a technical report rather than to influence the behavior of the reader. Likewise, a teacher may think their purpose is to cover the syllabus rather than to affect the behavior of the students. This is similar to how the purpose of many ingrained habits, communicational and otherwise, is to affect the environment even though the agent is often not aware of it while performing them. Berlo acknowledges such cases and understands them as forms of misperception or inefficiency.
Usually, the source has a specific person in mind whom they wish to affect. Intrapersonal communication is a special case: the source and the receiver is the same person. In such cases, the source tries to influence itself, like a poet who writes poetry in secret in order to emotionally affect themselves. However, the more common goal is to influence others. The intended effect can be immediate or delayed. An artist trying to entertain their audience intends an immediate effect while an employer giving instructions for the rest of the week intends to have a delayed effect on the employees' behavior. Messages can also produce unintended outcomes, such as when the intended receiver does not react as the source anticipated or when the message reaches unintended receivers.
Relation to earlier models
Berlo's model was influenced by earlier models like the Shannon–Weaver model and Schramm's model. Other influences include models developed by Theodore Newcomb, Bruce Westley, and Malcolm MacLean Jr. The Shannon–Weaver model was published in 1948 and is one of the earliest and most influential models of communication. It explains communication in terms of five basic components: a source, a transmitter, a channel, a receiver, and a destination. The source produces the message. To send the message, it has to be translated into a signal by the transmitter. To transmit this signal, a channel is required. At this stage, noise may interfere with the signal and distort it. Once the signal reaches the receiver, it is translated back into a message and made available to the destination. When making a landline phone call, the person calling is the source and their telephone is the transmitter. The wire is the channel and the person receiving the phone call is the destination. Their telephone is the receiver. Berlo made slight adjustments to many of the basic components of the Shannon–Weaver model to include them in his own model.Schramm's model of communication is another significant influence on Berlo's model. It was first published by Wilbur Schramm in 1954. For Schramm, communication starts with an idea in the mind of the source. This idea is then encoded into a message and sent to the receiver. The receiver then has to decode and interpret the message to reproduce the original idea. The concept of fields of experience plays a central role in this regard and was influential for Berlo. The field of experience of a person is their mental frame of reference and includes past life experiences as well as attitudes, values, and beliefs. Communication is only possible if the message is located within both fields of experience. If the message is outside the receiver's field of experience then they cannot reconstruct the sender's idea. This can happen when there are big cultural differences. Similar ideas are expressed in the SMCR model in the discussion of how attitudes, knowledge, and the social-cultural system of the participants shape communication.
Overview and basic components
The SMCR model is usually described as a linear transmission model of communication. Its main focus is to identify the basic parts of communication and to show how their characteristics shape the communicative process. In this regard, Berlo understands his model as "a model of the ingredients of communication". He identifies four basic components: source, message, channel, and receiver. The source is the party that wants to communicate an idea. They have to encode this idea in the form of a message. The message contains the information to be transmitted. The channel is the means used to send the message. The receiver is the audience for whom the message is intended. They have to decode it to understand it.Despite the emphasis on only four basic components, Berlo initially identifies a total of six components. The two additional components are encoder and decoder. The encoder is responsible for translating the idea into a message and the decoder is responsible for translating the message back into an idea. Berlo holds that these six components are necessary to account for communication in its most general sense. However, the model can be simplified to four components for regular person-to-person communication. This is the case because source and encoder can be grouped together as one entity, just like decoder and receiver. In this regard, Berlo speaks of the source-encoder and the decoder-receiver. Treating the additional components separately is especially relevant for technical forms of communication. For example, in the case of a telephone conversation, the message is transmitted as an electrical signal and the telephone devices act as encoder and decoder.
Each of the four main components is characterized by parts that influence the communicative process. Berlo's main interest in discussing them is to study the conditions of the fidelity of communication. For Berlo, every communication is motivated by a goal the source intends to achieve and fidelity means that the source gets what they want. Fidelity is also called effectiveness and is the opposite of noise.