A bit of direct instruction
The ideas that the three psychologists, Clark, Kirschner and Sweller (Ed. Psychol. 2006 42(2)99-107) are putting forward to support their argument for direct instruction are:
The brain is made up of structures, cognitive structures which handle learning. Two of these structures are the working memory and the long term memory. Their existence is demonstrated by experiments in psychology over a long period. Being described as structures means the long term and working memory have stable and fixed natures. Since they are not physical structures but what the psychologists term ‘cognitive structures’ they cannot be seen but their existence is implied as a logical outcome of the experimental work.
This is how these cognitive structures function.
Long-term memory is a data store of unlimited capacity the access to which is via the working memory. Information is sorted and assigned to storage areas by the working memory. Stored information in the long term memory is not open to conscious inspection. It can move back from this store to the working memory structure to be used as the basis for action which may be conscious or unconscious. Having been transferred to working memory it also remains in the store unchanged. Learning is defined as a change in information in the long-term memory store structure. (What about forgetting?)
The working memory structure receives information both from the environment and from the long-term memory store and is open to conscious inspection.
When information comes from the external environment and it is new information, termed novel information, the working memory has strictly limited capacity – from 2 to 7 pieces of information at one time. It holds information for from 30 seconds to several minutes after which time this information is lost from the working memory. When the amount of information moving into working memory at one time is too great, from 3 to 8 pieces of information at one time, it becomes overloaded. The psychologists call this ‘cognitive overload’. The working memory has two distinct functions; it holds incoming information – up to 7 pieces at one time; it sorts this information and passes it to the long-term memory for storage.
When information comes from the internal environment, from the long-term memory store, the working memory structure assumes a different function and in this configuration can store and process unlimited amounts of information. It does not demonstrate cognitive overload with information from the long term memory store. When handling information from the external environment it will recognise this information and adopt the strictly restricted format for this type of information whilst processing the long term stored information with no restrictions whatsoever. The working memory does not carry out both functions simultaneously, but switches from overload-possible to overload-impossible mode.
This notion of the change in function of the memory structures when exposed to information from external or internal sources has been explained by another psychologist. This answers this question; Why does a baby not experience cognitive overload when it is handling very large amounts of novel information, to do with language, walking, social communication etc.? His explanation is that all information falls into one of two groups, this information is processed into becoming knowledge biologically primary knowledge and biologically secondary knowledge. He suggests that in the course of the evolutionary process some information, relating to the biological needs of the individual is recognised by the cognitive structures as forming a group. This information group bypasses the working memory to be stored in large amounts in the long term memory, thus removing the possibility of cognitive overload occurring. The second group, biologically secondary knowledge, is formed from that information which schools deliver to children, the information which makes up the academic curriculum. This category is recognised also as novel information (as was that making up the biologically primary knowledge group) but because of its biologically secondary nature is routed to the long term memory via the working memory which will experience cognitive overload unless direct instruction by the instructor regulates the flow of information to a slow enough rate for the limited capacity working memory in this configuration to handle it. Both working and long term memory have a mechanism which allows them to identify and separately handle biologically primary and secondary information which can be processed to biologically primary and secondary knowledge
It has been proposed by another psychologist that to explain this difficulty of a structure apparently fundamentally changing its form and function when exposed to different types of information, novel or previously categorised and stored, there is an additional structure which he calls long-term working memory. This third structure would have unlimited storage and processing capability. This structure has not been fully explained as it has not been the subject psychological experiments.
Psychologists state that the mode of instruction must match the cognitive structures established by psychologists through evidence obtained by experimentation over time.
The psychologist’s proposed structure of working memory is overloaded by too much information being delivered to it at one time and its capacity is strictly limited. When the learner is a novice, the only way to ensure the working memory can operate without becoming overloaded and non-functional is to utilise direct instruction. The procedure for direct instruction is for the teacher to fully explain the concept about to be taught to the novice learners. Immediately following this a pattern of information is delivered to the learners which surrounds and supports the previously explained concept. As all information is novel and coming from the outside environment the working memory structure is operating in strictly-limited, fast-decaying mode. The rate of delivery of information is controlled by the instructor to enable the working memory structure to operate without becoming overloaded, avoiding ‘cognitive overload’ as it is known by psychologists. Evidence from psychological investigation demonstrates that the when the learner is a novice, direct instruction is fast and effective, as assessed by psychological tests.
As the novice builds their store of information on a specific topic in their long term memory store structure over time they become expert. As experts their working memory handles unlimited amounts of information without becoming cognitively overloaded.
Quoting from the Clark et al (2006) paper:
“Working Memory Characteristics and Functions
Working memory is the cognitive structure in which conscious processing occurs. We are only conscious of the information currently being processed in working memory and are more or less oblivious to the far larger amount of information stored in long-term memory.
Working memory has two well-known characteristics:
When processing novel information, it is very limited in duration and in capacity. We have known at least since Peterson
and Peterson (1959) that almost all information stored in
working memory and not rehearsed is lost within 30 sec and
have known at least since Miller (1956) that the capacity of
working memory is limited to only a very small number of elements. That number is about seven according to Miller, but may be as low as four, plus or minus one (see, e.g., Cowan,2001). Furthermore, when processing rather than merely storing information, it may be reasonable to conjecture that the number of items that can be processed may only be two or three, depending on the nature of the processing required.
The interactions between working memory and long-term memory may be even more important than the processing limitations (Sweller, 2003, 2004). The limitations of working memory only apply to new, yet to be learned information that has not been stored in long-term memory. New information such as new combinations of numbers or letters can only be
stored for brief periods with severe limitations on the amount
of such information that can be dealt with. In contrast, when
dealing with previously learned information stored in long-term memory, these limitations disappear. In the sense that information can be brought back from long-term memory to working memory over indefinite periods of time, the temporal limits of working memory become irrelevant. Similarly, there are no known limits to the amount of such information that can be brought into working memory from long-term memory. Indeed, the altered characteristics of working memory when processing familiar as opposed to unfamiliar material induced Ericsson and Kintsch (1995) to propose a separate structure, long-term working memory, to
deal with well-learned and automated information.
Any instructional theory that ignores the limits of working memory when dealing with novel information or ignores the disappearance of those limits when dealing with familiar in formation is unlikely to be effective. Recommendations advocating minimal guidance during instruction proceed as though working memory does not exist or, if it does exist, that it has no relevant limitations when dealing with novel information, the
very information of interest to constructivist teaching procedures. We know that problem solving, which is central to one instructional procedure advocating minimal guidance, called inquiry-based instruction, places a huge burden on working memory (Sweller, 1988). The onus should surely be on those who support inquiry-based instruction to explain how such a procedure circumvents the well-known limits of working memory when dealing with novel information.”
Clark and his collaborators still hold to their explanation, as evidenced by their Spring 2012 paper pages 6 to 10 in the American Educator, They state that ‘gold standard’ randomised controlled trial experiments should be conducted to establish direct instruction as the method which matches the cognitive structures they propose. The cognitive structures that they require instruction methods to match up to are at present figments of their fertile psychologists’ imaginations. There is an absence of experimental evidence to incontrovertibly establish the existence of any of a highly sophisticated and dynamic information processing system which underpins their direct instruction argument. As a biologist I cannot yet see the adaptive advantage of a highly restricted gateway to novel information/learning in individual humans.
Maybe inquiry pedagogy circumvents the unproven working memory/long term memory structural problem and the whole memory/knowledge system operates as whole, powered by the agency of the learner. Of course I can’t prove it.