Date of Award


Document Type


Degree Name

Master of Science (MS)


Department of Psychology

First Advisor

Julie M. Campbell


Role-differentiated bimanual manipulation (RDBM) is a complex behavior requiring the complementary movement of two hands to achieve a common goal. The current study investigated the relation of RDBM efficiency (speed to complete a successful RDBM) with hand preference, toy type (simple/difficult), age, and hand used to perform the RDBM. This study observed 46 infants between the ages of 9 to 14 months, each with a different hand preference category. Changes in RDBM efficiency across time were examined across different hand preference groups for RDBMs performed on simple toys using the right hand. The analysis revealed that early-right preference infants had a steeper slope than the no-preference/left-preference infants. The same was true for right-preference infants (early- and late-) for RDBMs performed on difficult toys using the right hand. A mixed ANOVA revealed that there were decreases in RDBM times across age therefore RDBM efficiency improves as the infants get older, regardless of toy type, hand used, or hand preference. The results of the present study suggest that when exploring the development of hand preference, we should consider the influence of age, hand preference, and hand used.


Imported from ProQuest Cortina_ilstu_0092N_11691.pdf


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