Jeanette, a 60-year-old woman, participates in a competition in which the participants are asked to memorize a list of words and then recall them in the same order in less than 2 minutes. In this competition, the participant who recalls the maximum number of words in the right order will be the winner. Unfortunately, Jeanette is not able to recall more than 10 words. In the context of the Seattle Longitudinal Study, Jeanette is most likely showing a decline in the mental ability referred to as