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The importance of memory
Why should this absolutely God-given faculty retain so much better the events of yesterday than those of last year, and, best of all, those of an hour ago? Why, again, in old age should its grasp of childhood’s events seem firmest? Why should repeating an experience strengthen our recollection of it? Why should drugs, fevers, asphyxia, and excitement resuscitate things long since forgotten? . . . such peculiarities seem quite fantastic; and might, for aught we can see a priori, be the precise opposites of what they are. Evidently, then, the faculty does not exist absolutely, but works under conditions; and the quest of the conditions becomes the psychologist’s most interesting task.
William James (1890), quoted in Principles of Psychology, i. 3
In the quote above, William James mentions some of the many intriguing aspects of memory. In this chapter, we will touch on some of its fascinating features. However, in a chapter of this length and scope we will, of course, only really be able to scratch the surface of what has been one of the most thoroughly researched areas of psychological enquiry.
The reason for the range of work that has been conducted into
the questions of what, why, and how we remember should be apparent: memory is a key psychological process. As stated by the eminent cognitive neuroscientist Michel Gazzaniga: ‘Everything in life is memory, save for the thin edge of the present’. Memory allows us to recall birthdays, holidays, and other significant events that may have taken place hours, days, months, or even many years ago. Our memories are personal and ‘internal’, yet without memory we wouldn’t be able to undertake ‘external’ acts — such
as holding a conversation, recognizing our friends’ faces, remembering appointments, acting on new ideas, succeeding at work, or even learning to walk.
Memory in everyday life
Memory is far more than simply bringing to mind information encountered at some previous time. Whenever the experience of some past event influences someone at a later time, the influence of the previous experience is a reflection of memory for that past event.
The vagaries of memory can be illustrated by the following example. Without doubt, you have seen thousands of coins in
your lifetime. But let us reflect on how well you can remember a typical coin that you may have in your pocket. Without looking
at it, take a few minutes to try to draw a coin of a particular denomination from memory. Now compare your drawing with the coin itself. How accurate was your memory for the coin? For instance, was the head facing the correct way? How many of the words (if any!) from the coin did you recall? Did you place these words correctly?
Systematic studies were conducted into this very topic in the 1970s and 1980s. Researchers found that, in fact, most people have very poor memories for very familiar things – like coins. This represents a type of memory which we tend to take for granted (but which – in a sense – doesn’t really exist!). Try it with other familiar objects in your environment, such as stamps, or try to remember the details of clothes that other people in your workplace or with whom you frequently socialize typically wear. The key point here is that we tend to remember the information that is most salient and useful for us. For instance, we may be much better at recalling the typical size, dimensions or colour of coins than the direction of the head or the text on the coin, because the size, dimensions or colour may well be more relevant for us when we are using money (i.e. for the primary purpose of payment and exchange for which money was devised). And when remembering people, we will typically recall their faces and other
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You are your memory
distinguishing features that remain relatively invariant (and are, therefore, most useful in identifying them), rather than items which may change (such as individuals’ clothing).
Instead of thinking of coins and clothing, it is perhaps more straightforward for most people to consider the role of memory in the case of a student who i) attends a lecture, and ii) later brings to mind successfully what was taught in the lecture in the examination hall. This is the type of ‘memory’ that we are all familiar with from our own school days. But it may be less obvious that memory may still play an effective role for the student, even when the person does not ‘remember’ the lecture or the information per se, but instead uses information from the lecture more generally (i.e. possibly without thinking about the lecture itself – or recalling the specific information that was presented in that context; this is termed episodic memory).
Constructing memory
As we have seen from the work of Bartlett, memory is not a veridical copy of the world, unlike a DVD or video recording.
It is perhaps more helpful to think of memory as an influence of the world on the individual. Indeed, a constructivist approach describes memory as the combined influences of the world and the person’s own ideas and expectations. For example, the experience of each person while they are watching a film will be somewhat different because they are different individuals, drawing upon different personal pasts, and with different values, thoughts, goals, feelings, expectations, moods and past experiences. They might have been seated next to one another in the cinema, but in an important sense they actually experienced subjectively different films. So an event, as it occurs, is constructed by the person who experienced it. This construction is greatly influenced by the memory ‘event’ (in this case, the film screening), but it is also a product of each person’s individual characteristics
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You are your memory
and personal idiosyncrasies (all of which play a substantial role
in how the event is experienced, encoded and subsequently stored).
Later, when we come to try to remember that event, some parts
of the film come readily to mind, whereas other parts we may re-construct – based on the parts that we remember and on what we know or believe must have happened. (The latter is likely to be predicated on our inferential processes about the world, combined with the elements of the film that we recall.) In fact, we are so good at this sort of re-construction (or ‘filling in the gaps’) that we are often consciously unaware that it has happened. This seems especially likely to happen when a memory is told and retold, with different influences present at each time of retrieval (see the reference to Bartlett’s techniques of serial and repeated reproduction cited in the box on page 15). In such situations, the ‘re-constructed’ memory often seems as real as the ‘recollected’ memory. This is an especially worrying consideration when we reflect on the degree to which people can feel that they are ‘remembering’ crucial features of a witnessed murder or a personally experienced childhood assault, when – instead – they may be ‘re-constructing’ these events and filling in missing information based on their general knowledge of the world (see Chapter 4).
In the light of these considerations, the act of remembering has been likened to the task of a paleontologist who constructs a dinosaur from an incomplete set of bones, but who possesses a great deal of general knowledge about dinosaurs. In this analogy, the past event leaves us with access to an incomplete set of bones (with occasional ‘foreign’ bones that are not derived from the past event at all). Our knowledge of the world then influences our efforts to re-assemble those bones into something that resembles the past episode. The memory that we assemble may contain some actual elements of the past (i.e. some real bones), but – taken as a whole – it is an imperfect re-construction of the past located in the present.
How we study memory today
Memory can be studied in many ways and in many situations. It can be manipulated and studied in the ‘real world’. However, most objective research on the topic of memory conducted to date has comprised experimental work, in which different manipulations are compared under controlled conditions (typically, in a laboratory setting) involving a set of to-be-remembered words or other similar materials. The manipulation might include any variable that is expected to influence memory, such as the nature of the material (e.g. visual vs. verbal stimuli), the familiarity
of the material, the degree of similarity between study and test conditions, and the level of motivation to learn. Traditionally, experimental researchers have studied memory for the following types of stimuli: lists of words, non-word stimuli such as those used by Ebbinghaus, and other commonly available materials such as numbers or pictures (other sorts of materials have been used too; including texts, stories, poems, appointments and life events).
Over recent decades, much of the empirical research into
memory that has been conducted has typically been interpreted
in the context of information processing and computer models
of memory that were adopted by most experimentalists after
the Second World War. Within this framework, the functional properties underlying human memory (and other aspects of cognitive functioning) are considered broadly to reflect the type of information processing embodied by the modern computer. (Note that this metaphor typically refers to the functional properties or software of the computer, rather than to its hardware.) More recent research studies typically involve larger numbers of participants than were tested in the earlier work conducted by Ebbinghaus
and Bartlett — who often focused on detailed examination
of individual cases (including — in Ebbinghaus’ case — himself!). Findings from group studies can be analysed using powerful inferential statistical techniques which enable us to interpret objectively the size and significance of the findings obtained.
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