Introduction:
Dual coding theory is based on the general view that the cognition activity of symbolic representational systems and sensory-motor systems are specialized for dealing with environmental information. This view incorporates perceptual, affective, and behavioral knowledge implies in representational systems. Therefore, the sensory-motor system includes visual, auditory, haptic, taste, and smell.
What Is Dual Coding Theory?
Symbolic system includes
- Verbal: visual words, auditory words, and writing patterns
- Non-verbal: visual objects, environmental sounds, “feel” of objects, taste memories, and olfactory memories
Theory:
Dual coding theory postulates verbal and imaginal representations that encode word and object information, respectively, as well as connections that exist between
- Sensory events and the symbolic representations
- Verbal and imaginal representations
- Representations within the two symbolic systems
Dual coding theory does not include a level of representation that is any more abstract than verbal representation and imaginal representation.
It is postulated by Paivio in 1971
Verbal representations or logogens:
A word-like entity comprised of visual and phonemic features having priority in human recognition.
Logogens demonstrate certain distinct properties characteristic of language.
Properties
- Language consists of discrete, categorical, and separate units that can be isolated from one another and even combined to produce new units.
Example: Discrete letters or phonemes (e.g., n, 0, s, e) are combined into discrete morphemes or words (e.g., “nose”) that can be combined further into phrases (e.g., “bloody nose”) and sentences.
- Sequentially constrained with meaning determined by the temporal and serial order of the elements
Example: nose” is different from “eons” and “John hit” from “hit John.” Sequential constraints are further demonstrated by our inability to verbalize more than one sound or word at a time
Imaginal representations or imagens:
According to dual coding theory, visual-spatial images demonstrate the distinctive properties of the nonverbal system better than motor images, which are organized both sequentially (as is language) and synchronously.
It encodes modality-specific information about nonverbal, perceptual, and sensory-motor experiences, conscious imagery being one way that images manifest themselves.
In particular, objects are stored as integrated, continuous, analog, or holistic representations that cannot easily be partitioned into discrete elements comparable to letters.
Example: an image for “nose” is nested along with other parts in an image for “face” and parts themselves can often be broken into finer segments (e.g., “nostrils”)
Processing Level or kinds:
According to dual coding theory, logogens and imagens are implicated in three different levels or kinds of processing
Representational processes
Familiarity is the major psychological correlate of representational processes.
Representational processes include low-level, stimulus-driven aspects of perceptual recognition or identification and are primarily governed by the physical characteristics of and experience with the words or objects themselves.
It operates whenever logogens or imagens are activated, but they are perhaps most purely seen when mental representations are stimulated relatively directly by suitable words or objects external to the organism.
Example: someone for whom “nos” and” <” are meaningless patterns may encode them as the word “nose” or as an image of a nose, respectively.
Referential processes
It operates when imagens and logogens activate representations in the other symbolic system using connections that develop between verbal and imaginal representations as a consequence of increasingly complex experiences with objects and their names.
The actual operation of these referential processes is most purely reflected in such tasks as imaging words and naming pictures
Example: referential connections permit the word “nose” to activate various images and appropriately shaped objects to activate various logogens (e.g., “nose,” “smell;’ “Nez”)
Associative processes
It operate when logogens activate other logogens and imagens activate other imagens. These processes use within-system connections among images in the nonverbal system and among logogens in the verbal system, including connections among verbal representations of abstract words that do not refer to concrete things
Such associative networks store knowledge about our verbal and nonverbal worlds.
Example: the logogen for “nose” is associatively connected to other logogens (e.g., “smell,” “part of the body;’ “face;’ “red”) and images for “nose” are associatively related to other images (e.g., “face;’ “eye;’ “person;’ “room”), including those within which it is nested.
Encoding in dual coding analysis:
Mnemonic encoding operations that implicate representational, referential, and associative levels of processing for both verbal and nonverbal materials.
Dual coding theory maintains that the basic associative and referential structures are sufficiently powerful to explain more complex networks, including those used in metacognitive processing. For example, instructions “to image” provide a verbal context that increases the probability of imaginal reactions relative to instructions “to associate.”
| Modality | Level | Operations |
| Verbal | Representational | Reading Natural language mediation Mnemonic keywords |
| Referential | Imaging Mental comparisons | |
| Associative | Free association Category production Free-recall clustering Associative priming | |
| Nonverbal | Representational | Perceptual identification Assimilation to the known object |
| Referential | Picture naming Object-word comparisons | |
| Associative | Integration by compound imagery Method of loci and cognitive maps Concrete scripts and schemas |
Encoding Processes for Verbal Stimuli
Memory traces for language result from a combination of representational, referential, and associative encoding processes.
These levels of encoding depend partly on one another in that a verbal stimulus can only engage imaginal and verbal associative encoding processes after prior activation of a logogen.
However, representational encoding does not guarantee referential or associative processing, which is in turn relatively independent of one another.
Representational Encoding of Unfamiliar Verbal Stimuli
According to dual coding theory, novel verbal stimuli (for example the Finnish word “norsu” and the nonsense syllable “cit”) are made more memorable by being encoded as familiar words or phrases (e.g., as “nurse” or “city”).
Imaging to words:
Dual coding theory postulates that referential connections between logogens and imagens permit indirect activation of images by words, as in imagery production tasks.
Imagery is only one “deeper” form of encoding for language materials and we now turn our attention to associative encoding processes for verbal stimuli.
Associative Encoding of Words
According to dual coding theory, activation spreads not only to imagens but also to other logogens, as demonstrated by free associations or such restricted associates as opposites, properties, instances of categories, and activities.
The latency of such associates provides one measure of their ease or strength. Many variables influence verbal associative reactions. During childhood, age is associated with decreases in associative latencies.
Verbal associative mechanisms contribute to elaboration and organization effects in memory. Elaboration refers to encoding processes that activate information stored about the word in the verbal system and is related to the idea of depth or levels of processing.
Organizational processes operate when presented words are related to one another either directly or indirectly. Direct associations between presented words benefit free recall, interfere with recognition memory, or interfere with such associative tasks as paired associate learning.
Encoding Processes for Nonverbal Stimuli
Dual coding theory characterizes the encoding of nonverbal stimuli in terms of representational, referential, and associative processes analogous to those that we have discussed for language.
Objects are encoded representationally when they activate familiar images, which in turn can activate logogens and other images by referential and associative processes.
Representational Encoding of Novel Objects
Unfamiliar figures access familiar imaginal representations by processes based on perceptual similarity and transformation. The operation of these processes is demonstrated when subjects draw novel shapes from memory
Verbal responses have also been used to indicate the meaningful encoding of random shapes and nonsense forms.
Activation of familiar images by unfamiliar patterns can be studied relatively directly and contributes to our understanding of the processes by which such patterns are learned and remembered. One of the ways that representational encoding facilitates memory is by enabling the learner to invoke higher-level processes, including referential encoding (i.e., naming), to which we now turn.
Naming Objects
Mental connections between images and logogens permit referential encoding of nonverbal stimuli, an operation that is invoked whenever we name pictures or objects. Although rapid, naming colors and pictures take longer than reading words.
Several direct measures of naming, especially latency, have been shown to elucidate basic referential mechanisms that may help us to understand parallel effects in memory tasks involving pictures or objects. Naming is only one of two “deeper” levels of processing available for nonverbal materials and we examine the next tasks and operations that reflect associative connections among imaginal mental representations.
Imaginal Associative Processing
Dual coding theory describes complex images as nested sets of more elementary units spatially organized into continuous, perceptual hierarchies that lack sequential constraints.
Pictures and objects have been shown to involve representational, referential, and associative encoding processes analogous to those used in encoding verbal stimuli and the results from direct investigations of these processes shed some light on their contribution to memory for nonverbal materials.
Conclusion:
Dual coding theory proposes that Reflexive knowledge of memory is represented in the same verbal and nonverbal symbolic systems as other knowledge; Its acquisition depends upon relevant experiences, including the reflexive application of the learning strategies themselves to strategy acquisition; Environmental stimuli activate relevant metacognitive knowledge, either directly (e.g., instructions to “image”) or through associative and referential connections (e.g., such learning related words and events as “remember” and classroom settings);
Metacognitive logogens and imagens exert control over the encoding of stimuli by priming general classes of associative or referential reactions (e.g., “image car” versus “synonym car”). Our fundamental knowledge about cognition is primarily empirical in nature and dual coding theory, conceived several decades ago as a general model of awareness, is a useful framework within which to conceptualize the accumulated research findings that provide an increasingly precise understanding of the memory encoding processes available in the verbal and imaginal symbolic systems.
