Answer to Question 1
According to dual-code theory, we use both pictorial and verbal codes for representing information in our minds. These two codes organize information into knowledge that can be acted on, stored somehow, and later retrieved for subsequent use. According to Paivio, mental images are analog codes. Analog codes resemble the objects they are representing. For example, trees and rivers might be represented by analog codes. Just as the movements of the hands on an analog clock are analogous to the passage of time, the mental images we form in our minds are analogous to the physical stimuli we observe. In contrast, our mental representations for words chiefly are represented in a symbolic code. A symbolic code is a form of knowledge representation that has been chosen arbitrarily to stand for something that does not perceptually resemble what is being rep- resented. Just as a digital watch uses arbitrary symbols (typically, numerals) to represent the passage of time, our minds use arbitrary symbols (words and combinations of words) to represent many ideas.
Answer to Question 2
Declarative knowledge refers to facts that can be stated, such as the date of your birth, the name of your best friend, or the way a rabbit looks. Procedural knowledge refers to knowledge of procedures that can be implemented. Examples are the steps involved in tying your shoelaces, adding a column of numbers, or driving a car. The distinction is between knowing that and knowing how.
Trichromatic Theory of Color Vision
The Human Genetic Code
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Theory of Plate Tectonics
The Two-Factor Theory of Emotion
Deciphering the genetic code with synthetic mini- mRNAs