Previous studies provided evidence of an ascending left-to-right spatial representation of time durations by using a technique affecting high levels of spatial cognition, i.e. prismatic adaptation (PA). Indeed,PA that induced a leftward aftereffect distorted time representation toward an underestimation, while PA that induced a rightward aftereffect distorted time representation toward an overestimation.The present study advancesprevious findings ontheeffectsofPAontimebyinvestigatingtheneuralbasis subtending theseeffects.Wefocusedontheposteriorparietalcortex(PPC)sinceitisinvolvedinthe PAprocedureandalsointheformulationofthespatialrepresentationoftime.Weconductedtwo experimentswhereright-handedhealthyadultsweresubmittedtoatimetask,beforeandafterPA,that could inducealeftwardorrightwardaftereffect.RepetitiveTMS(rTMS)wasusedtoinhibittheleftor right PPCbeforePAadministration.Ina first experimentthetimetaskconsistedofreproducinganhalf duration (timebisectiontask)bypressingakeyandtheparticipantsrespondedandadaptedtoprisms with theirrighthand.Inasecondexperimentthetimetaskconsistedofreproducingawholeduration (time reproductiontask)bypressingakeyandtheparticipantsrespondedandadaptedtoprismswith their lefthand. WefoundanabolitionoftheeffectsofPAontimewhenrTMSwasdeliveredontheleftandnoton the rightPPC,regardlessofthetaskandmoreover,whentheparticipantsrespondedandadaptedwith the righthandandalsowiththelefthand.ThisresultsuggestsadirectinvolvementoftheleftPPCinthe interactiveprocess,betweenspatialmodulationsinducedbyPAandthespatialrepresentationoftime, that doesnotdependonmotorprocesses.Thisstudyprovidesusefulresultsforfutureinvestigationson the neuralmechanismssubtendingtheeffectsofPAonspatialrepresentations.
The role of posterior parietal cortices on prismatic adaptation effects on the representation of time intervals / Barbara Magnani;Giuseppa Renata Mangano;Francesca Frassinetti;Massimiliano Oliveri. - In: NEUROPSYCHOLOGIA. - ISSN 0028-3932. - STAMPA. - 51:(2013), pp. 2825-2832. [10.1016/j.neuropsychologia.2013.08.006]
The role of posterior parietal cortices on prismatic adaptation effects on the representation of time intervals
FRASSINETTI, FRANCESCA;
2013
Abstract
Previous studies provided evidence of an ascending left-to-right spatial representation of time durations by using a technique affecting high levels of spatial cognition, i.e. prismatic adaptation (PA). Indeed,PA that induced a leftward aftereffect distorted time representation toward an underestimation, while PA that induced a rightward aftereffect distorted time representation toward an overestimation.The present study advancesprevious findings ontheeffectsofPAontimebyinvestigatingtheneuralbasis subtending theseeffects.Wefocusedontheposteriorparietalcortex(PPC)sinceitisinvolvedinthe PAprocedureandalsointheformulationofthespatialrepresentationoftime.Weconductedtwo experimentswhereright-handedhealthyadultsweresubmittedtoatimetask,beforeandafterPA,that could inducealeftwardorrightwardaftereffect.RepetitiveTMS(rTMS)wasusedtoinhibittheleftor right PPCbeforePAadministration.Ina first experimentthetimetaskconsistedofreproducinganhalf duration (timebisectiontask)bypressingakeyandtheparticipantsrespondedandadaptedtoprisms with theirrighthand.Inasecondexperimentthetimetaskconsistedofreproducingawholeduration (time reproductiontask)bypressingakeyandtheparticipantsrespondedandadaptedtoprismswith their lefthand. WefoundanabolitionoftheeffectsofPAontimewhenrTMSwasdeliveredontheleftandnoton the rightPPC,regardlessofthetaskandmoreover,whentheparticipantsrespondedandadaptedwith the righthandandalsowiththelefthand.ThisresultsuggestsadirectinvolvementoftheleftPPCinthe interactiveprocess,betweenspatialmodulationsinducedbyPAandthespatialrepresentationoftime, that doesnotdependonmotorprocesses.Thisstudyprovidesusefulresultsforfutureinvestigationson the neuralmechanismssubtendingtheeffectsofPAonspatialrepresentations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
