June 22, 1994

This text is essentially a set of notes taken from Chapter 9 of Dennis Coon's Introduction To Psychology; Exploration to Application, 1992, West End Publishing Company.

Memory is a system which encodes, stores and retrieves information. There are several phases; sensory, short-term and long-term. Sensory memory is exact but brief; through selective attention, some contents are transferred to STM, where they are further processed. Although STM can only hold around seven bits of info, by chunking or recoding info this can be extended. STM contents can be lost through interruption midway through processing, or expiration, if they were ignored for too long (20+ seconds), or simply fall out the back, if more info is coming in. STM contents can be refreshed by rehearsal.

LTM is relatively permanent memory of seemingly unlimited capacity that stores what has been determined to be meaningful information. This memory is organised to facilitate retrieval. Objects pass from STM to LTM through an encoding process; often the new data is assimilated by linking it with data already present in LTM.

Memory can be activated by the act of recall, recognition of data, or the relearning of data. Recall provides no cues (an essay question), while recognition requires the subject select an answer from a list or similar (multiple choice), while relearning involves going over old material again; often the second time the learning process will be quicker and more permanent. The serial position effect documents the propensity of items in the middle of a list to be forgotten.

Consolidation theory proposes that engrams - memory traces - are formed shortly after learning, and if these engrams are not consolidated (reconciled with existing data) then the memory is lost. The hippocampus has been linked with this phenomenon.

Eidetic imagery, or photographic memory, occurs when the subject is able to recall a scene by projecting it onto a "blank surface" and recalling detail. This is uncommon in adults, but adults do use memory images which are incomplete but nonetheless vivid.

Forgetting is most common immediately after learning (presumably this is a problem with STM -> LTM transfer). Faulty encoding or disuse account for some forgetting, and data seemingly forgotten can be recalled through use of cues. Moods have some effect on the ability to remember. Sometimes new learning conflicts with old; this is retroactive interference, while old learning conflicting with new learning is proactive interference.

Repression is the act of subconsciously enforcing "forgetting", so as to hide a nasty memory, while suppression is the same thing but it is a conscious act.

Memory can be improved by using feedback, recitation and rehearsal, by selecting and organising data before an attempt is made to learn it, by spaced practice and overlearning. The effects of sleep, serial position, reviews, cues and elaboration should be considered when learning is attempted.

Mnemonic systems are methods of facilitating data encoding by making data more memorable.