Sex, age, and sex hormones affect recall of words in a directed forgetting paradigm

Abstract

During the course of serious discussion, an unexpected interruption may induce forgetting of the original topic of a conversation. Sex, age, and sex hormone levels may affect frequency and extension of forgetting. In a list-method directed forgetting paradigm, subjects have to learn two word lists. After learning list 1, subjects receive either a forget or a remember list 1 cue. When the participants had learned list 2 and completed a distraction task, they were asked to write down as many recalled items as possible, starting either with list 1 or list 2 items. In the present study, 96 naturally cycling women, 60 oral contraceptive users, 56 postmenopausal women, and 41 young men were assigned to one of these different experimental conditions. Forget-cued young subjects recall fewer list 1 items (list 1 forgetting) but more list 2 items (list 2 enhancement) compared with remember-cued subjects. However, forget-cued postmenopausal women showed reduced list 1 forgetting but enhanced list 2 retention. Remember-cued naturally cycling women recalled more list 1 items than oral contraceptive users, young men, and postmenopausal women. In forget-cued follicular women, salivary progesterone correlated positively with recalled list 2 items. Salivary 17β-estradiol did not correlate with recalled list 1 or list 2 items in either remember- or forget-cued young women. However, salivary 17β-estradiol correlated with item recall in remember-cued postmenopausal women. Our findings suggest that sex hormones do not globally modulate verbal memory or forgetting, but selectively affect cue-specific processing. © 2016 Wiley Periodicals, Inc.

Keywords: cognitive aging; estradiol; estrogen; learning and memory.