Sex Differences in the Strategies of Tactile Object Memory in Early Adulthood

Everyday life inevitably involves touch. Encoding, recalling and recognizing objects by touch requires tactile object memory. Most likely tactile object memory requires verbal and visual capabilities. This fosters the question whether performance or strategies applied for solving the tactile memory task are sex-dependent. We assessed 42 healthy young adults (24 females, 17 males; age 18–36 years). Participants were asked to memorize ten objects of high everyday utility with eyes closed and touching the objects. With a delay of five minutes subjects were asked to recall as many objects as possible and subsequently to recognize the objects from a selection of five conceptually identical but perceptually different objects while eyes were open. Regardless of whether the participants were able to identify the object correctly, they were allowed to then touch the object. Performance of women and men was alike. Due to inferior verbal memory, men applied mental rotation as a back-up strategy. Women were generally better in verbal memory so that back-up strategies were not used. Later in recognition by touch, using mental rotation sufficed to solve the task for men while women solved the task using verbal memory again. We conclude that tactile object memory is subject to sex-specific strategies while performance is similar for both sexes. With task difficulty exceeding men’s verbal capabilities, men tap into mental object rotation.