1.1. Generation-Recognition theory
1.2. Encoding-Specificity theory
Memory is our ability to rely on past experience in order to inform our current experience. There are various forms of remembering. Here, we are going to investigate recall and recognition in more detail. We are interested in finding the information processing steps in either type of retrieval. This specifies the stages of how information is represented to solve the task, the sequence of steps that operate over that information, and how an outcome is ultimately generated.
1.1. Generation-Recognition theory.
According to the generation- recognition theory1, there is only one process of remembering called recognition: the presentation of a stimulus either externally (in the world) or internally (an idea that comes to mind) causes activation of other concepts in our mental state. Successful recognition occurs when the presented cues activate a concept. Critically, according to the generation-recognition theory hypothesis, recall is a two stage process consisting of two steps: 1.) Generate a list of possible alternatives, and 2.) Apply a recognition procedure to the internal list and output the item which is recognised. This account therefore assumes that recognition is a prerequisite for cued recall. Therefore, recall performance should always be worse than (or equal to) recognition performance.
1.2. Encoding-Specificity theory.
The encoding-specificity hypoth- esis may be stated as follows: “What is stored is determined by what is perceived and how it is encoded, and what is stored determines what retrieval cues are effective in providing access to what is stored.” The theory suggests that recall performance could be greater than recognition in the Cued Recall & Recognition test (see Methods section) because at study participants were encouraged to think about the pairs of words in terms of one another. The greater episodic trace from this encoding process of two words at once could imply that the paired cue can act as a better retrieval cue than the word itself.
The Cued Recall & Recognition test was conducted in four stages:
(1) The subject is presented with a list of 24 weakly associated cue-TARGET pairs to learn and told that the experiment will only consist of stage (4): recalling the TARGET word in capitals given the cue word.
(2) The subject performs free-association to words similar to target words. He or she needs to find four words as quickly as possible.
(3) The subject is asked to recognise target words from a list and to rate their confidence.
(4) The subject is asked to recall words given the initial cues.
This task is a simplified form of experiments by Watkins & Tulving, which demonstrated recall of words was sometimes possible even when these items were not easily recognised. In this design, recognition may be impaired by interference from the free association task in the second stage, as many of the target words are likely to be generated as associates) making it difficult to decide during the recognition test if the word was in the first stage. The performance on the cued recall improves due to the extra “context” provided by the the cue word based on encoding-specificity theory. Two groups were allocated and performed the experiment with a slightly modified set of stimuli in order to determine whether or not any effects that we have found are due to the specific stimuli used or due to a a more general effect. An independent (unpaired) two-tailed samples t test was performed based on the H 0 hypothesis that there is no significant difference in the proportion of words recalled, but not recognised, between the two groups, which both consisted of 21 human subjects using a critical value of α = 0 . 05.
The performance of the 42 subjects in the Cued Recall & Recognition test was found to be 0 . 27 ± 0 . 19 (see Table 1) as the proportion of words that were recalled, but not recognised. In a two tailed t -test, we found t (40)0 . 05 = 1 . 168, and, thus, we retained H 0: “There is no significant difference in the proportion of words recalled, but not recognised, between the two groups due to the external stimuli used.”1
First of all, we need to take into account that our sample of 42 Part IB Psychology students at the University of Cambridge is only a “good estimator” of a population of intelligent, young adults. Regarding the experimental design, Martin2 is one of the main critics. He argues that Tulving and Thomson’s contradiction to the generation- recognition theory of recall with the phrase “recognition failure of recallable words”3 is not an admissable summary of their experiments, as the word LIGHT in the cue-target pair head-LIGHT is not the same as the word LIGHT in the free-association pair dark-LIGHT. In his opinion, the encoding specificity principle does not talk about LIGHT, only about LIGHT (lamp) and LIGHT (luminance), which would not imply that LIGHT (lamp) is not simultaneously retrievable and not recognizable, as the experiments did not address the question designing the tasks to guarantee LIGHT (lamp) in retrieval but LIGHT (luminance) in free association and recognition He mainly focused on this one example to demonstrate his assumption that every word is, to some extent, a homograph, so it is questionable if this approach can be used as a fundamental critique of the whole experimental design.
In conclusion, we verified the Encoding Specificity Theory by showing that there was a significant proportion of words recalled, but not recognised (0 . 27 ± 0 . 19), and that this was not due to the external stimuli we used in our task given that we found t (40)0 . 05 = 1 . 168 in a two tailed t -test, and, thus, we retain H 0: “There is no significant difference in the proportion of words recalled, but not recognised, between the two groups.”
1. John R Anderson and Gordon H Bower, A propositional theory of recognition memory, Memory & Cognition 2 (1974), no. 3, 406-412.
2. Edwin Martin, Generation-recognition theory and the encoding specificity princi- ple., (1975).
3. Endel Tulving and Donald M Thomson, Encoding specificity and retrieval pro- cesses in episodic memory., Psychological review 80 (1973), no. 5, 352.
4. Michael J Watkins and Endel Tulving, Episodic memory: When recognition fails., Journal of experimental psychology: General 104 (1975), no. 1, 5.
1 The F test was performed to justify the use of a t -test. F = 1 . 173 < 2 . 46, hence p> 0 . 05see Table 1.