The limited capacity model of motivated mediated message processing (LC4MP) is the most recent version of a data-driven model that tries to explain how human beings process all types of mediated messages (A. Lang 2000, 2006a, 2006b). This model differs from the vast majority of communication theories in a number of ways.
First, it is not an effects theory. That is to say that it makes no effort to examine the relationship between some specific type of content in a media message and a later behavioral action. Second, it is not a theory about a specific type of media content (violence, politics, sex, advertising, health). Instead, its goal is to generalize to all types of content and to completely describe the realm of possible contents through psychologically relevant independent variables such as emotion, difficulty, relevance, redundancy, narrative strength, etc. Third, this theory is not limited to a specific medium but is meant to be relevant to all currently existing media and those not yet invented. Again, this means that media are described not by their names (radio, TV, computer, video game) but instead by a set of psychologically relevant variables (channel of information presentation, range of structural features, luminance, content forms, movement, etc.). Finally, the theory is data-driven. This means that it is constantly evolving so as to remain compatible with the state of knowledge in related disciplines and in the field of communication.
The broad outline of the theory is simple. It involves five assumptions, three subprocesses, two systems, and automatic and controlled resource allocation mechanisms. Each aspect of the theory has at least one validated operational definition. The complexity lies not in the overarching framework of the theory but rather in the task of explicating the specifics of the theory in the myriad of contexts to which it applies.
The Five Assumptions
The five assumptions of LC4MP arise primarily from theories of information processing and theories of emotional processing. The first assumption, a primary tenet in most cognitive psychological theorizing, is that humans are limited capacity information processors. This means that human beings have a fixed pool of resources with which to process their environment. If the demands of the tasks in which they are engaged exceed this limit then some of those tasks will be done less well. This assumption gives rise to the fundamental concept of cognitive overload. Cognitive overload is defined as a state that arises whenever the demands of an information-processing task exceed one’s available processing capacity.
The second assumption, from emotion research, is that people have two motivational systems that produce fundamental drives to approach positive stimuli and avoid negative ones. These two systems, the appetitive and the aversive motivational systems, function automatically and independently to protect and maintain the individual. Together these first two assumptions lead to a second central concept in LC4MP, embodied motivated cognition. This concept maintains that the brain is not just riding around on top of the body telling it what to do, but instead is one of many organs in the interconnected biological system that makes up a human being and functions as a primary influence on the cognitive system.
The third assumption in this theory is that all functioning in the system occurs over time. Each part of the system responds within its own characteristic time frame to specific types of inputs. At any one point in time, the functioning of any one aspect of the system is multiply determined by the state of the system in the moment preceding the point of interest, the current psychologically relevant characteristics of the environment, and the limits of the system.
The fourth assumption is that mediated messages are made up of continuous streams of variably redundant information being presented in one or many perceptual channels using a variety of symbol systems. Messages are not defined by industry descriptions related to technology, content, or genre. Instead, they must be defined in terms of psychologically meaningful variables (e.g., rate of change, movement, luminance, etc.).
Fifth, communication is the interaction between the motivated cognitive system, the context in which the interaction occurs, the psychologically relevant aspects of the medium that carries the message, and the psychologically relevant aspects of the content of the message.
Taken together, these assumptions lay the groundwork for a theory that tries to explain the dynamic interaction of the motivated cognitive system with the psychologically relevant aspects of the medium’s structure and the message’s content to determine how a message is attended to, encoded, stored, and subsequently retrieved.
As previously noted, LC4MP is a limited capacity information-processing model. Information processing is thought to involve both automatic and controlled processes. Processes are conceived of as requiring cognitive resources. Automatic processes occur without conscious awareness, require few cognitive resources, and cannot be stopped. Controlled processes require a fair number of cognitive resources and can be consciously initiated and terminated.
Processing a mediated message is theorized to involve at least three cognitive subprocesses: encoding, storage, and retrieval. The theory maintains that resources are allocated independently to the three sub-processes through both controlled and automatic mechanisms. Thus, in the absence of a voluntary intention by a media user to pay attention to or remember a specific type of content, automatic processes allocate resources to encoding, storage, and retrieval as a function of the psychologically relevant aspects of the media message. However, media users can, through controlled resource allocation, improve or inhibit how these automatic processes function by intentionally altering their message processing behavior.
The encoding sub-process involves creating a mental representation of the information in the message. This process is not thought to be veridical. Messages are not encoded either exactly or completely. This is because at any given point in time most messages contain more information than can be completely encoded. As a result, a continuous process of selection and encoding occurs. The selection process is guided by both automatic and controlled processes. Some elements of messages are selected because they engage automatic resource allocation mechanisms through the manipulation of psychologically relevant variables. LC4MP theorizes two primary routes to automatic resource allocation. First, elements of messages that create novelty by introducing new information to the message (e.g., cuts, edits, video graphics, sound effects, etc.) or are signals that viewers have learned indicate important content (e.g., slow motion, words, etc.) elicit orienting responses, which are automatic attention mechanisms resulting in the allocation of cognitive resources to encoding the message. Second, emotional, or motivationally relevant, content also results in the automatic allocation of resources to encoding.
The second sub-process, storage, is conceptualized as the process of connecting new information to already stored information. LC4MP does not subscribe to a specific memory theory or architecture; it conceptualizes memory within the general framework of associative network spreading activation models. When one is aware of stored information, its representation is thought to be active. Links are formed when two representations are concurrently active. Activation spreads automatically through the links from active to related inactive information. Stored information can be partially activated through spreading activation making that information more accessible. Within this framework, storage is conceived of as the process of creating links between incoming information and previously stored information. When more resources are allocated to storage, more and stronger links are forged between old and new information. The allocation of resources to the storage process is also influenced by automatic and controlled resource allocation mechanisms. Motivationally relevant information is thought to result in the automatic allocation of resources to storage. Viewers can also increase the allocation of resources to storage through controlled processes and cognitive effort.
The third sub-process is retrieval. Retrieval plays two roles in this theory, first as online or real-time retrieval and second as delayed retrieval of the information presented in a mediated message. In either case, retrieval is the process of fully activating a stored representation. Online retrieval is the process of activating previously stored information in order to make sense of an incoming message. Much of this retrieval occurs automatically through the process of spreading activation. As the media message is perceived, it activates relevant representations already stored in memory, and previously stored information relevant to the topic is fully activated or retrieved. Second, there is the process of retrieving the information being presented in a message at a later date. It is thought that the better the information in the message is stored the more likely it is to be retrievable at a later point in time.
The two underlying motivational systems, appetitive and aversive, are integrated into the current version of LC4MP based on the theoretical conceptualizations found in John Cacioppo’s dual system theory (Cacioppo & Gardner 1999) and P. J. Lang’s dimensional emotional theory (Lang et al. 1997). Each system is theorized to have its own activation function. These functions are characterized by two variables called the positivity offset and the negativity bias.
Positivity offset is the tendency of the appetitive motivational system to be more active in a neutral environment, and the negativity bias is the tendency of the aversive system to activate more quickly than the appetitive system in response to moderately arousing stimuli. LC4MP theorizes that activation in the appetitive motivational system results in increased allocation of resources to encoding and storage, while increased activation in the aversive motivational system elicits an increase in resources allocated to storage, and an increase followed by a decrease (at very high levels of activation) in resources allocated to encoding. Thus, LC4MP predicts that at very high levels of activation, positive stimuli should be encoded and stored well, whereas negative stimuli are thought to be stored extremely well but encoded less well.
Each process in LC4MP has at least one validated operational definition. The three memory processes are measured using three different memory protocols – encoding is indexed through recognition measures (including latency, accuracy, and signal detection measures); storage is assessed using cued recall protocols; and retrieval is measured using free recall measures. Resource allocation is measured using secondary task reaction time methodology or by measuring heart rate. Heart rate can be analyzed beat by beat to measure orienting responses to a specific aspect of a message, or its long term deceleratory or acceleratory trend can be assessed to index cognitive effort. Appetitive activation is indexed by inhibition of the startle response, increased activation in the zygomatic and orbicularis oculi muscles, and facilitation of the post-auricular response, and through self-report ratings of positive emotional experience. Aversive activation is indexed by startle facilitation, increased activation in the corrugator muscle, and increased selfreported ratings of negative emotional experience. The level of activation in the motivational systems is indexed by skin conductance and self-reported level of experiential arousal.
The use of this theory and measures allows one to analyze media and media messages in terms of the structural and content features they contain that lead to increased or decreased levels of resources allocated to encoding and to storage. By measuring the level of information introduced over time within messages in conjunction with automatic calls for resources, it is possible to identify – over time – the points at which the system is overloaded (and therefore encoding and storing less information) and when it is functioning optimally. This theory also provides a framework on which to investigate the extent to which motivational activation alters the message processing functions and ultimately influences later actions, attitudes, and behaviors.
- Cacioppo, J. T., & Gardner, W. L. (1999). Emotion. Annual Reviews: Psychology, 50, 191–214.
- Lang, A. (2000). The information processing of mediated messages: A framework for communication research. Journal of Communication, 50, 46 –70.
- Lang, A. (2006a). Using the limited capacity model of motivated mediated message processing (LC4MP) to design effective cancer communication messages. Journal of Communication, 56, 1– 24.
- Lang, A. (2006b). Motivated cognition (LC4MP): The influence of appetitive and aversive activation on the processing of video games. In P. Messarsis and L. Humphries (eds.), Digital media: Transformation in human communication. New York: Peter Lang, pp. 237–256.
- Lang, P. J., Bradley, M. M., & Cuthbert, B. N. (1997). Motivated attention: Affect, activation, and action. In P. J. Lang, R. F. Simons, & M. T. Balaban (eds.), Attention and orienting: Sensory and motivational processes. Hillsdale, NJ: Lawrence Erlbaum, pp. 97–136.