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Boundary Extension Is Sensitive to Hand Position in Young and Older Adults
Kristi S Multhaup1, Margaret P Munger1, Kendra C Smith1
1Psychology Department, Davidson College, North Carolina.
Objectives:
Based on preliminary reports, we expected an age-related increase in boundary extension (BE), a phenomenon in which people falsely remember seeing more of a scene than was presented. Given recent data suggesting hand-centered attentional frames in young adults contrasted with body-centered attentional frames in older adults, we predicted hand-position effects on BE in young adults only.
Method:
Participants (59 young, 60 older adults) viewed photographs of complex scenes (e.g., a market) and answered yes/no questions about each. Half answered with key presses while their hands were framing the computer monitor; half while their hands were on a lapdesk. At test, participants indicated whether photographs were the same as, or at a closer or wider angle than at study.
Results:
Both age groups demonstrated BE. When study-test angles were the same, participants rated test pictures as closer than at study. When study-test angles differed, older adults showed less BE than young adults. For both same- and different-angle conditions, there was a main effect of hand position (less BE when hands framed the monitor than when on participants' laps).
Discussion:
The data confirm older adults show BE but show no age-related increase. Surprisingly, both young and older adults showed hand-centered attention.
