SECTION FOUR Memory and Cognition

This section of the manual continues our discussion of the concept of cognition and presents a description of how—at a physiological level—people learn, that is how human mental processes retain knowledge acquired through training. An understanding of these processes and their limitations are useful to instructional professionals because they have significant implications for the work we do in the classroom.

A great deal has been written about memory and memories, but both from a philosophical and practical perspective the mechanisms of the recall of past experiences and facts are as yet incompletely understood. Most specialists acknowledge that a significant part of the problem is that there are so many different kinds of memory. You may recall the sound of your mother’s voice, the colour of grass, the date of a loved one’s birthday, the result of multiplying 6 times 8, the directions to find your way home, the smell of roses, and on and on. Each comes from memory but springs from such different sources and involves different senses.

There are numerous ways of classifying memory and recollection, depending on the type of memory referred to. Memory of facts is sometimes termed “propositional memory” or “semantic memory.” By facts we mean that the concepts which provide a foundation for the way the world works—how many hours in a day, the temperature of boiling water, the value of pi, or the number of players on a side in football are all memory of this type. Another category of memory is known by various names: experiential memory, recollective memory, or episodic memory. This kind of recollection concerns both particular and general past experiences, such as a discussion we may have had with friends or the smell of our favourite food being cooked.

Some experts also make a distinction between “explicit” and “implicit” memory. Explicit memory refers to those memories which a person can consciously recall and express to others, whereas implicit memories are ones that a person may be unaware of. The problem with this distinction is that different causes are known to exist for the lack of awareness of memories. Sometimes memories are suppressed from consciousness because of the pain they might inflict. Some are merely temporarily forgotten. How often have your struggled to recall a person’s name whom you know, then without any prompting it comes to you days or weeks later? Obviously, the name could not have been truly forgotten, otherwise it would have been lost forever. The fact that it could be remembered later indicates that the memory existed somewhere, but it could not be accessed by the active brain until something enabled its recollection. Finally, there may also be memories that are buried deep in sub-consciousness, hidden away and not available until something triggers its remembrance. It is upon these sorts of memories that much of psychoanalytic theory is based.

A central aspect of cognitive learning is that the way human brains process information apparently has three modes: short-term memory (also called working memory), long-term memory, and sensory memory. Each mode appears to operate rather differently and call upon different portions of the brain to function. The importance to training of each sort of memory varies also as will be described below.

Short-term memory. The acquisition of information to be retained for relatively short periods of time is commonly referred to as short-term memory, or “working” memory. Working memory is conceptualized as somewhat like a scratchpad on which notes are jotted for application within a short period of time. For instance, suppose you wanted to make a telephone call to schedule an appointment. You would look up the number and quickly memorize the number, then dial it. Ten minutes later, you would not be able recall the number. The length of time information can be held in short-term memory might be just seconds or at most minutes before it is lost. This might seem to be a problem for trainers, but it actually can be seen as

an advantage. Dropping items from memory that serve no further purpose avoids the mental jumble that might otherwise accumulate. Suppose your memory were cluttered with long-unused names, facts, and other trivia. It is really better to remember some things only long enough to use them, and then they should be discarded when they no longer are useful.

To see how short-term memory works, try this experiment. Below are listed sixteen items that are randomly selected and connected in no particular way. Allot yourself two minutes to memorize the list of words.

Mango tree Shoe
Tea pot Pencil
Shirt Sewing thread
Auto horn Desk
Toothbrush Dish
Window Camera
Keyboard Hammer
Toy whistle Tablet

Now, continue reading.

 
Most cognitive specialists draw a distinction between short-term memory and working memory. They consider the former to be a system of storing information for brief periods of time, whereas the latter is viewed as a system for temporary storage and manipulation of information. In this concept, the working memory is a bit like the microprocessor in your computer and is the source of consciousness. In other words, our working memory is responsible for what we are aware of at any given moment.

Interestingly, it is known that working memory is located in a few highly localized areas of the human brain. In the late 1990s after quite a few years of study, researchers finally succeeded in pinpointing the exact location for working memory’s storage of spatial concepts—that is, where things around us are located. The success was aided by scientists’ knowledge of where this memory was located in monkey brains. In humans, the location is just in front of an area of the brain that is used to control eye movements, in the middle upper portion of the frontal cortex. This discovery was an important step forward. One benefit is that it has enabled scientists to better understand why short-term memory is sometimes harmed in persons suffering from severe mental illnesses such as schizophrenia.

Now, back to that list of random items. On a separate piece of paper, jot down each one that you remember. When you complete all that you can recall, look back at the list to check on their accuracy. How many items did you correctly remember? The difficulty of a learning task like this rises as the number of items to be retained is increased until finally the capacity of short-term memory is reached and you cannot memorize the entire list. At this stage, one has reached what is known as cognitive overload. The amount of “processing” demanded of working memory exceeds its limits. Research has shown that about seven (give or take two) bits of information are about all that can be held in short-term memory. For this reason, telephone numbers in most countries are limited to seven or eight digits. More digits than this and it would become difficult to retain the numbers while dialling.

There are some people who have claimed to possess “photographic” memory, that is to say an ability to remember a huge amount of information at a single glance and to retain it indefinitely. There is little doubt that memory, like most human capabilities, varies from person to person, but there seems to be mounting evidence that such “photographic” abilities are exaggerated. To date, no scientifically accepted demonstration of this capability has been documented. True, there are individuals who have trained themselves to perform remarkable memory feats. Some people can memorize the order of cards in a deck in a matter of seconds and chess masters can hold in memory chess piece positions of multiple games simultaneously, and while blindfolded can play—and usually defeat—multiple opponents at the same time. However, in these and similar instances such abilities are narrowly developed. The person with a remarkable memory of card order might not have any unusual ability to remember names. An interesting puzzle in this regard is that there are some autistic individuals who exhibit astounding memory abilities. How this occurs and how their memory functions is something of a mystery.

Somewhat related to this subject is eidetic memory. This is the ability to retain for a period of time a highly detailed visual memory of a scene, including colours and spatial relationships within the image. Even though most youngsters do not possess this kind of memory, it is more commonly seen among children. Also, after six years of age, most children with eidetic memory find that their abilities begin to fade rapidly, and genuine eidetic memory among adults is very rare.

Long-term memory. We do need to keep some information indefinitely, of course. Long-term memory is used to retain important and useful information for long periods, perhaps for years, decades, or a lifetime. Even in long-term memory, our brains are constantly culling through the items stored to find ones that can be discarded. For example, can you recall your family’s telephone number used when you were a child? When you were a youngster that telephone number was important, and you made use of it often enough to retain it in long-term memory. But today you may not use the number any longer or it may have changed. Retaining in memory an obsolete telephone number has no purpose, so perhaps you have moved it out of long-term memory. But, in contrast, you probably would have no difficulty recalling the appearance of your childhood house (its color, size, the arrangement of rooms, etc) because these facts stored in long-term memory are still relevant to your life due to their personal significance. Fortunately, our long-term memory appears to have an unlimited capacity, so we need not worry about overloading our memory storage ability.

When information is retrieved from long-term memory, it must pass through working memory where it can be processed for immediate use. In fact, there is a continual exchange that takes place between the two memory storage modes. For instance, it is accepted that information to be stored in long-term memory must first be processed through short-term memory. Our brains have the capacity to shift learning from short-term memory into long-term storage and move information in the reverse direction when needed. The ease and speed with which information can be moved through these memory processes varies from person to person, and research suggests that individual differences in learning abilities may stem in large part from the different functional capacities of individuals’ working memory.

It is plainly evident that the task of trainers must be one of ensuring that learning is not just temporarily placed in short-term memory, but moved onward into long-term memory. Obviously, training is of little value if all we can do is enhance knowledge of information for short periods of time. However, unlike long-term memory, short-term memory has a limited capacity, as noted previously. For some individuals in some situations, their working memory may have a capacity of as little as four pieces or “chunks” of new information, but in any case not likely more than seven or eight.

In training, the need to pass information through this limited storage capacity poses a serious problem. Short-term memory acts as a bottleneck and forces us to rely on special tactics to ensure information is transferred to long-term memory. Trainers thus need to pursue a strategy in which a few bits of information are given learners, followed by an activity that will aid in shifting the information from their working memory into long-term memory. Time is required for rendering a memory into long-term storage, a process that is termed “consolidation.” In consolidation, information is incorporated into the pre-existing structures are the schema referred to in the preceding section of this manual. Higher-level information of the sort involved in training can require long periods of time for consolidation, perhaps days or weeks; this is needed to reorganize schema to accommodate the new complicated learning.

Therefore, making certain that the learning is moved from short-term to long-term memory is a crucial responsibility of the trainer. There are several ways to combat the tendency for information in short-term memory to be quickly disposed of; each involves making the knowledge more memorable. Perhaps the most important technique is to link the new learning to knowledge that learners already have internalized. In other words, to incorporate learning into the schema of information already in place in the learner’s long-term memory. If new learning extends knowledge already in long-term memory, it is more likely to be retained in long-term memory too.

A related approach is to “chunk” information or to combine together bits of information so that they can be stored as one, perhaps collectively forming a new node in an existing network schema. An example of this is to use a mental cue such as “SMARTE” (see Section Seven for an explanation of this acronym) to internalize a list of learning points.
An interesting aspect of consolidation is the role of sleep in its success. It has long been proposed that during sleep the memory processes are somehow enhanced. The old saying that one should “sleep on” difficult or perplexing information to better understand it, may actually have a basis in fact. Research has found some support for the sleep enhancement thesis, especially for memorization of facts and experiences, indicating that consolidation processes are busy at work while one sleeps.

A particularly efficient way of enhancing consolidation is to link new learning to something unusual or odd. Training that employs peculiar audio-visual material, or uses presentations containing surprises or other unusual features seems to improve learners’ preservation of information. Presumably, this occurs for at least two reasons—first, the learners’ attention will be more readily captured by the novelty of the presentation, which of course is a requirement of any learning exercise, and second the learner will be more motivated by the novelty to undertake the mental effort required to restructure schema.

In the end, there is no substitute for repetition of learned information. Repeating material, technically known as rehearsal, helps freshen the learning in short-term memory, eventually leading to its transfer to long-term memory. For example, consider that task of looking up a telephone number and dialling it. If you repeat aloud the number several times or if you write it down on a notepad, it is much more likely that you’ll be able to retain the number long enough to dial it. If you only read the number and then dial it, you may have to re-read the number again to get it right. Rehearsal works best if the trainer varies the way repetition occurs. If the training repeats material already presented but offering slightly different explanations, different examples, or different ways of understanding the topic, it not only makes the material more interesting, it speeds the conversion to long-term memory. But remember that even if we succeed in moving cognitive learning from short-term to long-term memory, there is no guarantee it will remain there. Because our minds are constantly looking for ways of discarding information no longer needed, we may forget learning unless it is regularly used, that is unless it continues to receive rehearsal.

It is well known that memory functions decline with age, but the impairment is mostly associated with working memory. An experience common among middle aged and older persons goes like this: one makes a decision to move to another room but a distraction occurs while walking to it, and on arrival the purpose of the shift in rooms cannot be recalled. Even though memory abilities are hampered by aging, the commonly held belief that learning capabilities drop sharply with age has not been verified by research. Many experts think that learning in healthy adults can continue to an indefinite age, though research is still underway on this.

Sensory memory. The third category of memory, sensory memory, is used when information is registered by our senses: touch, hearing, smell, vision, and taste. This memory is very short-term, typically lasting less than one second. To understand how this type of memory works, close your eyes. Wait for a few seconds, then blink your eyes open for just a moment. Note that the image from your eyes remained for a fraction of a second after your eyes closed again—sensory memory provided that brief glimpse of the image after the visual stimuli disappeared. This kind of memory is important from a physiological point of view but does not seem to have a significant role in training.