Adaptive memory

Adaptive memory is the study of memory systems that have evolved to help retain survival- and fitness-related information, i.e., that are geared toward helping an organism enhance its reproductive fitness and chances of surviving. One key element of adaptive memory research is the notion that memory evolved to help survival by better retaining information that is fitness-relevant. One of the foundations of this method of studying memory is the relatively little adaptive value of a memory system that evolved merely to remember past events. Memory systems, it is argued, must use the past in some service of the present or the planning of the future. Another assumption under this model is that the evolved memory mechanisms are likely to be domain-specific, or sensitive to certain types of information. Adaptive memory is the study of memory systems that have evolved to help retain survival- and fitness-related information, i.e., that are geared toward helping an organism enhance its reproductive fitness and chances of surviving. One key element of adaptive memory research is the notion that memory evolved to help survival by better retaining information that is fitness-relevant. One of the foundations of this method of studying memory is the relatively little adaptive value of a memory system that evolved merely to remember past events. Memory systems, it is argued, must use the past in some service of the present or the planning of the future. Another assumption under this model is that the evolved memory mechanisms are likely to be domain-specific, or sensitive to certain types of information. A recent development in the field of evolutionary psychology, adaptive memory was first proposed in 2007 by James S. Nairne, Sarah R. Thompson, and Josefa N.S. Pandeirada. Evolutionary psychologists often state that humans possess a 'stone-age' brain. Therefore, optimal cognitive performance may be found in problems faced by our ancestors, or related to the environments in which our evolutionary ancestors lived. Based on this finding, Nairne and his colleagues proposed that human memory systems are 'tuned' to information relevant to survival. The first study on the subject of adaptive memory was published in 2007 and its methodology has been replicated many times since. Participants were told to imagine themselves in one of three randomly assigned scenarios. In the Survival condition, they imagine being stranded in a grassland area of a foreign land, and need to find a steady supply of food and water, and protect themselves from predators. The second condition was the Moving condition. Participants were instructed to imagine themselves moving to a foreign land, needing to locate a new home and transporting their possessions. Finally, the Pleasantness condition asked participants to simply rate the pleasantness of a list of words. In the Survival and Moving conditions, participants were asked to rate the relevance of each word on a list to their imagined situation. Participants were then subject to a surprise recall test. Nairne et al. found what they called the survival advantage. The survival advantage means that information that is more salient, or relevant, to survival in an ancestral environment has a higher rate of retention than control conditions. This became clear following free recall experiments conducted by Nairne and colleagues. Processing information relevant to survival leads to more information being remembered than most known encoding techniques. One explanation for the survival advantage's improved retention is that this kind of processing taps into a sort of memory 'module' specialized for remembering and processing information that is important for survival. Another proposed explanation is that it leads to more arousal and emotional processing. Because many survival situations are emotionally arousing, retention is enhanced. An important first step toward a functional analysis of survival processing is thinking about the kinds of problems memory would have evolved to solve. Figuring out selection pressures can be difficult. Post-hoc accounts, also known as just-so stories, are an important problem to avoid. Nairne et al.'s work stressed the importance of a priori predictions, and designing empirical tests. A very important element of studying adaptive memory to consider, like other scientific research, is its basis on empirical evidence and study methodology. The methodology for testing adaptive memory and the survival advantage in human participants has thus far mostly consisted of ranking lists of words by their relevance to a survival setting (and along control dimensions as well), followed by a recall session. The basic research methodology involves having participants rate a series of words by their fitness relevance. In the control condition, the words were rated for their relevance to moving for a foreign land, and their pleasantness. A surprise recall test is administered, and recall of the listed words in all three conditions is recorded and analyzed. One major finding is that survival processing has been shown to yield better retention than imagery, self-reference and pleasantness, which are all considered to be among the best conditions for remembering learned information. Otgaar, Smeets and van Bergen hypothesized that since visual processing developed earlier than language, there ought to be a survival advantage for images as well as words, and they found such an advantage. Grasslands survival scenarios showed higher retention than near-identical scenarios in which the word 'grasslands' was replaced with 'city' and the word 'predators' replaced with 'attackers'. It is suspected that this result is due to the human mind being scenarios relevant to our species' ancestral past, even though threats present in a modern urban society are far more relevant today. There was a greater memory recall in both the ancestral and modern survival conditions when compared to pleasantness control conditions, but only the ancestral condition presented significantly greater word recall. Both conditions are fitness-relevant, but there was no memory enhancement for survival processing in the modern context. Additionally, as females typically performed gathering tasks over the span of human evolution, and males performed hunting tasks, research into this gender dichotomy was conducted. No significant data were found. The implications of this research lie in helping to understand how the mind evolved and how it works. The idea that we are able to retain information most relevant to our own survival provides a foundation of research for empirical studying of memory through an evolutionary lens. Understanding the circumstances when memory is at its best can help study the functions of memory as a whole, and help understand what memory is capable of. The survival processing advantage has been shown to increase both true and false memory in adults and children. True memory refers to the correct retention of information. False memory means remembering something that was never present. A false memory is not necessarily maladaptive. Misremembering can have advantages in certain situations (for example, misremembering an environment with predator tracks as the actual presence of a predator may lead to avoidance of that area in the future). False memory can be seen as a side-effect to an otherwise highly adaptive process. One of the most important functions of memory is the ability to use learned information to make predictions in future planning. Adaptive memory states that memory was created and developed by the process of natural selection, so many components of memory systems were important for long-term planning, the importance of which is central to ensuring survival and the passing of genes.