A great deal of research from the information processing framework has been conducted on the topic of memory and aging. The general consensus is that certain memory functions do decline with age. This work must be interpreted with care. These two factors combined make it difficult to generalize across age groups because of subject and cohort bias. Subject bias comes from using people who do not necessarily represent the general population (such as college students versus the broad population of young adults). Cohort bias or effect is any difference between groups of adults of varying ages that is due not to any maturation or developmental process, but simply to the fact that the different age groups have grown up under different historical and cultural circumstances. Some of the authors of these studies do not define older adult. Tthey neither describe nor critique the study participants. The range of the older adult group was from fifty to eighty.