Hand Preference In Rela.on to Hand Skill at 2 Yearshands.fiu.edu/ICIS16_Hartstein.pdf · Lauren E....

CheerioTask–FineMotorAssessment

HandPreferenceInRela.ontoHandSkillat2Years

LaurenE.Hartstein1,VishakhaAgrawal1,ElizaL.Nelson2,NeilE.Berthier11UniversityofMassachuseGsAmherst,2FloridaInternaJonalUniversity

DevelopmentofHandedness

•  Consistenthandpreferenceforacquiringobjectsemergesby10-11monthsofageinroughly50%ofinfants1.

•  However,11-to-14-montholdsshownocleardifferencesinhandskillbetweenthepreferredandnon-preferredhand2.

•  By24monthsofage,nearly100%ofchildrenexhibitaconsistenthandpreferenceforrole-differenJatedbimanualmanipulaJon(RDBM)3.

•  Researchhassuggestedthatadultsincreasetheuseofthepreferredhandwhenskillisrequired,suchasincomplexmanipulaJontasks4.

Howarehandpreferenceandskillrelatedat2yearsofage,a.mepoint

whenmostchildrenexhibitaconsistenthandusepaCern?

RDBMTask–HandPreferenceAssessment

References

1.  Michel,G.F.,Babik,I.,Sheu,C.-F.,&Campbell,J.M.(2014).Latentclassesinthedevelopmentaltrajectoriesofinfanthandedness.DevelopmentalPsychobiology,50(2),349-359.

2.  Nelson,E.L.,Konidaris,G.D.,&Berthier,N.E.(2014).HandpreferencestatusandreachkinemaJcsininfants.InfantBehaviorandDevelopment,37,615-623.

3.  Nelson,E.L.,Campbell,J.M.,&Michel,G.F.(2013).Unimanualtobimanual:Trackingthedevelopmentofhandednessfrom6to24months.InfantBehavior&Development,36(2),181–188.

4.  Bryden,P.J.(2015).TheinfluenceofM.P.Bryden’sworkonlateralizaJonofmotorskill:IsthepreferredhandselectedforandbeGerattasksrequiringahighdegreeofskill?Laterality,1-17.

•  Two-year-oldsshowedlongerreachJmestoanobjectwiththeirpreferredhand,whichmaybeindicaJveofmorecareandprecision.

•  ThisrelaJonshipfollowedalineartrajectory,inthatstrongerright-lateralizaJonleadtolongerreachJmes.

•  Two-year-oldsfiGedaball

intotheaperturemorequicklywiththeirpreferredhand,showingfinercoordinaJonwiththathand.

•  ResultsalsosupportarelaJonbetweenrighthanduseandtasksrequiringprecision.

•  FutureworkshouldexaminerighthandskillinaddiJonallej-handersandthosewithnoclearhandpreference.

By2years,arela+onshipemerges

betweenhandpreferenceandskill.

high

Conclusions

HandpreferencedistribuJon

•  20childrenhadarighthandpreferenceforRDBM.

•  Onechildhadalejhandpreferenceand1childhadnohandpreference.

BeeTask–FineMotorAssessmentMethod:•  Abeehivetoywithacircularapertureonthetopis

placedatchild’smidline,andaspherical“bee”isplacedinfrontofthechild’slejorrighthand.

•  Thechildisaskedtoputthebeeintothebeehive.•  ReachJmetothebee,Jmetograsp,andJmeto

transferthebeetotheholewerecoded.

Results:

•  HIwassignificantlycorrelatedwithreachJmeforthepreferredhand(r=.50,p=.03).

•  AsparJcipantsbecamemorerightdominant,theirreachJmewiththeirrighthandwaslonger.

60 70 80 90 100

400

500

600

700

Handedness Index

Rea

ch T

ime

Pref

erre

d H

and

(ms)

N=18

Method:•  Acupwithacheerioisplacedinfrontofchild,either

inlinewiththelejorrighthand,oratmidline.•  ReachJmetothecup,Jmetograsp,andJmeto

transferthecheeriotothemouthwerecoded.

Results:

•  Only7parJcipantscontributedsufficientdataforanalysis(mulJplereacheswitheachhand).

•  NosignificantdifferencesinJmebetweenhandswasfoundonanystageoftheacJon.

•  LargedifferencesingraspJmewithmuchshortergraspswiththepreferredhandwereobserved,butnotsignificant,possiblyduetoinsufficientpower.

•  HIdidnotpredictwhetherchildwasmorelikelytoreachwithlejorrighthandtocupplacedatmidline.

Results:

Preferred Hand Non-Preferred Hand0

200

400

600

Rea

ch T

ime

(ms)

Preferred Hand Non-Preferred Hand0

200

400

600

800

1000

Gra

sp a

nd T

rans

fer T

ime

(ms)

Method:•  22parJcipantsaged23to25months.

•  Given29role-differenJatedbimanualmanipulaJon(RDBM)taskstocompleteinwhichtheobjectmustbesteadiedwithonehandandmanipulatedwiththeotherhand(e.g.holdpouch,removetoyfrominside).4

•  AHandednessIndex(HI)wascalculatedforeachchildusingtheformulaHI=#Righthandresponses/Total

*•  Childrenhadamarginallylonger

reachJmewithpreferredhand.

•  Duringgraspandtransfer,reachJmesweresignificantlyshorterwiththepreferredhand.

Preferred Hand Non-Preferred Hand0

100

200

300

400

Rea

ch T

ime

(ms)

Preferred Hand Non-Preferred Hand0

1000

2000

3000

Gra

sp T

ime

(ms)

Preferred Hand Non-Preferred Hand0

200

400

600

800

Tran

sfer

Tim

e (m

s)

N=7

N=7

N=7

N=19 N=19

N=22