Functional Determinants of Memory

Purdue University, West Lafayette IN

Investigators

Abstract

Functional Determinants of Memory James S. Nairne Abstract Our capacity to remember is certainly the product of an extended period of evolution. Yet if human memory evolved, sculpted by the processes of natural selection, then its processes likely bear the "footprints" of ancestral selection pressures. In particular, our memory systems should be "tuned" to retain information that is fitness-relevant, pertaining to survival and reproduction. Until recently, psychologists have ignored this possibility, but work in the researcher's laboratory has shown that thinking about the survival relevance of information leads to superior long-term memory -- better, in fact, than virtually all known study techniques. As one example, asking experimental participants to rate a list of arbitrarily selected words for each item's potential survival value leads to significantly higher rates of recall and recognition than traditional study procedures (e.g., even effective techniques such as rating items for pleasantness or forming a visual image). Still, the psychological mechanisms that underlie fitness-relevant memory processing remain essentially unknown and largely unexplored. Do we have special memory mechanisms designed to retain fitness-relevant information? Are these mechanisms rooted in the remnants of a stone-age brain? Our research explores these questions by comparing and contrasting how memory operates in fitness-relevant and fitness-irrelevant situations. The research investigates memory's role in the formation of social contracts as well, and in the processing of prospective mating partners. Do people have special memory mechanisms for retaining information about people who cheat, perform altruistic acts, and for potential mates? Answers to these questions will be determined by having people imagine themselves in fitness-relevant situations, such as seeking food or a prospective mate, followed by the administration of diagnostic retention tests. Previous work suggests that the study of adaptive memory may lead to a fundamental reconceptualization of basic memory mechanisms: Rather than general processes designed to operate the same way in all environments, memory's operating characteristics may well vary depending on the particular problem context. To understand how memory works, and to develop effective techniques for memory improvement, it is essential to understand the function of memory and, more specifically, to understand how and why memory evolved. Memory likely evolved to help us solve adaptive problems, such as finding food, avoiding predators, or attracting prospective mates. Recognizing the adaptive roots of memory is key to understanding its basic mechanisms, just as understanding the adaptive function of the heart or the liver is vital to understanding their ultimate structure. The researcher's research systematically explores the function of memory in fitness-relevant contexts, such as the search for food, the avoidance of predators, or in assessing the trustworthiness of potential cheaters. Understanding how memory is used to solve the problems of survival, the formation of social contracts, and reproduction will provide critical insight into how and why memory systems formed, and why they work the way they do. As our understanding of memory's inherent "tunings" increases, our ability to calibrate our learning strategies, and to teach others to remember effectively, will increase as well. For example, educators commonly promote study strategies based on the processing of meaning, or "visualizing" the material, whereas the researcher has shown that a few seconds of focused adaptive processing (i.e., how is the material relevant to survival or dealing with significant others) produces substantially better long-term retention.