Human cognitive architecture:

an evolutionary perspective

Geary (2002, 2005, 2007, 2008) distinguishes between biologically primary and biologically secondary information. Biologically primary

information is knowledge we have evolved to acquire, while biologically secondary knowledge is taught in educational institutions. Learners are strongly motivated to acquire biologically primary information which can be acquired easily, rapidly and unconsciously just by immersion in a social context. Examples of such knowledge are oral/aural language acquisition, simple tool usage, and the reading of facial expression and body language. In contrast, biologically secondary information, such as written language and mathematics, requires considerable conscious effort and external motivation to acquire. It is this category of biologically sec-ondary knowledge for which schools and other education institutions were invented.

The cognitive architecture required to allow the acquisition of bio-logically secondary knowledge mirrors the processes and structures of evolution by natural selection. Both are examples of natural information-processing systems. Sweller and Sweller (2006) describe the analogy between human cognitive architecture and biological evolution using five basic principles.

4.2.1 Information store principle

In order to function in a natural environment, natural information pro-cessing systems must include a large information store to deal with the various contingencies with which they will be faced. In the case of evo-lutionary biology, that store is provided by a genome, while long-term memory provides a similar cognitive function. Evidence for the cen-tral importance of long-term memory in human learning, thinking and problem solving comes from the well-known studies demonstrating the role of long-term memory in the development of problem-solving exper-tise (Chase and Simon 1973; De Groot 1965). Highly skilled chess players normally defeat weaker opponents because they have stored tens of thousands of board configurations (Simon and Gilmartin1973) and the best moves associated with those configurations in long-term memory.

4.2.2 Borrowing and reorganizing principle

Mechanisms are required to rapidly build a large information store.

Natural information-processing systems build their stores primarily by borrowing information from other stores. Asexual reproduction provides an exact transmission of information, apart from mutations, from one store to another. Sexual reproduction ensures that borrowed informa-tion is first transmitted and then reorganized. Indeed, the reorganizainforma-tion

that is characteristic of sexual reproduction provides its primary function, ensuring that descendants differ from their ancestors and their siblings, apart from monozygotic siblings.

The bulk of biologically secondary information held in long-term memory also is borrowed. Most of it is obtained from other people.

We imitate what others do (Bandura1986), listen to what they say and read what they write. The cognitive load theory effects discussed below all depend directly on the borrowing and reorganizing principle.

4.2.3 The randomness as genesis principle

While most information held in long-term memory is borrowed, that information has to be created in the first instance. Random generate and test during problem solving is the only known mechanism for generat-ing creativity. In the case of biology, random mutation is the ultimate source of all biological novelty. Similarly, during problem solving, when knowledge is created, we virtually always use a combination of previ-ously known information and random generate and test. Whether we are attempting to find a problem-solving move or searching for an analogue, to the extent that information is not available in long-term memory, we have no choice but to engage in random generation followed by a test for effectiveness. Without sufficient information in long-term memory, we cannot know the outcome of a problem-solving move until we have made that move, either mentally or physically. Analogously, the consequences of a mutation cannot be assessed biologically until after it has occurred.

4.2.4 The narrow limits of change principle

The randomness as genesis principle has structural consequences. If randomness is a part of the creation of novel structures and functions, change must be small and incremental because a large, random change will almost certainly be dysfunctional. In biology, the epigenetic system (Jablonka and Lamb2005; West-Eberhard2003) mediates the manner in which outside influences affect the genetic system. Working memory has the same function in human cognition (Sweller and Sweller 2006) when it deals with novel information from the senses. That information must be organized by working memory and the organization tested for effectiveness before being stored in long-term memory. To ensure that the number of randomly generated, possible alternative organizational patterns is not overwhelming, working memory has well-known temporal (Peterson and Peterson1959) and capacity (Miller1956) limits.

4.2.5 The environmental organizing and linking principle

This principle provides the ultimate aim of natural information-processing systems. Not only must the system assimilate information from the external world, it must also simultaneously use the information store to organize the external world and generate appropriate action.

The epigenetic system can marshal huge amounts of genetic information from the same genome to determine vastly different biological structures and functions. For example, vastly different cells such as skin cells and liver cells have the same genetic code in their nuclei. Similarly, working memory can use massive amounts of organized information from long-term memory to delong-termine action. The vast amounts of information from long-term memory that can be processed over extended periods by working memory indicate that there are no temporal or capacity limita-tions of working memory when dealing with familiar information from long-term memory (Ericsson and Kintsch1995).

4.3 Working-memory characteristics and