Human Memory

Activity . Semantic memory , on the other hand, is the memory of general awareness and knowledge. All concepts, ideas and rules of logic are stored in semantic memory. For instance, it is because of semantic memory that we remember the meaning of say ‘non- violence’ or remember that + = or the STD code of New Delhi is or that the word ‘elaphant’ is misspelt.

Unlike episodic memory this kind of memory is not dated; you perhaps will not be able to tell when you learnt the meaning of non-violence or on which date you came to know that Bangalore is the capital of Karnataka. Since the contents of semantic memory relate to facts and ideas of general awareness and knowledge, it is affect-neutral and not susceptible to forgetting. See Box . K NOWLEDGE R EPRESENTATION AND O RGANISATION IN M EMORY In this section we will take a look at the organisational structure that the contents of long-term memory acquire over a period of time.

Since long-term memory holds a very large amount of information which is put to use with amazing efficiency, it would be very useful to know how our memory system organises its contents so that the right information is available at the right moment. It is important to note at this point that many ideas relating to organisation of the content of long-term memory have resulted from experiments that have employed semantic retrieval tasks. You will perhaps agree that there cannot be any error in recalling the contents of semantic memory. For anyone who knows that birds fly will not make a mistake in answering a question — Do birds fly?

The answer will be in affirmative. But people may take variable lengths of time in answering questions, which require semantic judgments. While responding to question ‘Do birds fly?’ a person will take not more than a second but answering a question ‘Are birds animals’? may take longer.

Depending upon how much time people take in responding to questions such as these, the nature of organisation in long- term memory has been inferred. The most important unit of representation of knowledge in long-term memory is a concept. Concepts are mental categories for objects and events, which are similar to each other in one or in more than one way. Concepts once formed get organised in categories — a category itself is a concept but it also functions to organise similarities among other concepts based on common features.

For example, the word mango is a category because different varieties of mangoes can be subsumed within it and it is also a concept within the category of fruit. Concepts may also There are many ways in which memory is measured experimentally. Since there are many kinds of memories, any method appropriate for studying one type of memory may not be suited for studying another. The major methods which are used for memory measurement are being presented here : a) Free Recall and Recognition (for measuring facts/episodes related memory) : In free recall method, participants are presented with some words which they are asked to memorise and after some time they are asked to recall them in any order.

The more they are able to recall, the better their memory is. In recognition, instead of being asked to generate items, participants see the items that they had memorised along with distracter items (those that they had not seen) and their task is to recognise which one of those they had learnt. The greater the number of recognition of ‘old items’, better is the memory. b) Sentence Verification Task (for measuring semantic memory) : As you have already read, .