Measuring Age Differences in the Effectiveness of Tactile Cues in Cellular Phones

Abstract

The trend of technology miniaturization has permeated the cellular phone industry and resulted in technology that has not only become smaller in terms of size, but slimmer resulting in flat-smooth keypads. Even though this trend has affected the majority of cell phone designs currently on the market, little to no research has examined the effects of this type of design on older adults.

The current study is comprised of four experiments designed to examine the effects of keypad surface on dialing performance as well as to identify aids that may enhance dialing performance. The first study examined differences in dialing performance between keypads with raised-rubber keys and flat-smooth keys as a function of age (i.e., younger versus older adults). The results revealed that both younger and older adults performed significantly better in terms of dialing accuracy and dialing time with the raised-rubber keypad.

The second study examined discrimination performance between various tactile cues. The findings from this experiment revealed that two tactile cues were readily discriminable for both age groups. These same discriminable tactile cues were then placed on existing raised-rubber keypads (in specific arrangements) to comprise the stimuli for Experiment 3. The findings from Experiment 3 revealed that only one of the four tactile cue arrangements significantly affected dialing performance.

In Experiment 4, however, the tactile cues that were not found to enhance dialing performance with the raised-rubber keypad were shown to enhance dialing performance with a flat-smooth keypad.

The results from this four-part study revealed that both younger and older adults performed significantly better in terms of dialing accuracy and dialing time with the raised-rubber keypad. Although the addition of tactile cues on the raised-rubber keypad did not significantly affect dialing performance, the addition of tactile cues on the flat-smooth keypad did significantly affect dialing performance.

These findings demonstrate that if future cellular keypad designs are flat and smooth in nature, the addition of tactile cues in specific locations can match dialing performance to that of the performance with the raised-rubber keypad. If tactile cues are not added to these types of keypad surfaces, however, these findings demonstrate how the trend of miniaturization and smooth keypads may potentially alienate the largest growing population in the U.S. (i.e., older adults) with respect to usability.