you were to come across the word ‘school’, an image of your own school will get generated. In fact, almost all concrete objects (and concepts) generate images and the knowledge related to them is encoded both verbally as well as visually. This is known as dual coding hypothesis , originally proposed by Paivio. According to this hypothesis, concrete nouns and information related to concrete objects are encoded and stored in the form of images while information related to abstract concepts assume a verbal and a descriptive code.
For example, if you are asked to describe a bird, the first thing that happens is that an image of a bird is generated and based on this image, you describe a bird. But, on the other hand, the meanings of concepts like ‘truth’ or ‘honesty’ will not have such accompanying images. So, any information which has been encoded verbally as well as in the form of images is recalled with greater ease. Eyewitness Memory Court procedures followed in criminal trials, use the testimony given by the eyewitness of the offense.
It is considered to be the most reliable evidence for or against the accused. Some experiments carried out by Loftus and her colleagues during the mid-seventies showed that the eyewitness’s memory is susceptible to many flaws. The experimental procedure followed by Loftus was very simple. A film clipping of an event (usually a car accident) was shown to the participants.
This was followed by some questions, which interferes with encoding of the event. One of the questions was “how fast were the cars going when they smashed into each other”. In another question the verb smashed was replaced with the verb contacted . Those who were asked the first question (which included the word ‘smashed’ ) estimated the speed of the cars as .
mph. Those who were given the second question (i.e. with the word ‘ contacted’ ) estimated that the speed of the cars was only . mph.
Clearly, the nature of leading questions changed the memory. In fact, the encoding of the event was ‘overwritten’ by misleading questions. Some