Show simple item record

dc.contributor.authorXu, Sisi
dc.contributor.otherQueen's University (Kingston, Ont.). Theses (Queen's University (Kingston, Ont.))en
dc.date2016-09-30 11:36:47.347en
dc.date.accessioned2016-10-03T21:29:02Z
dc.date.issued2016-10-03
dc.identifier.urihttp://hdl.handle.net/1974/15048
dc.descriptionThesis (Master, Neuroscience Studies) -- Queen's University, 2016-09-30 11:36:47.347en
dc.description.abstractTo reach for a target, we must formulate a movement plan - a difference vector of the target position with respect to the starting hand position. While it is known that the medial part of the intraparietal sulcus (mIPS) and the dorsal premotor (PMd) activity reflects aspects of a kinematic plan for a reaching movement, it is unclear whether or how the two regions may differ. We investigated the functional roles of the mIPS and PMd in the planning of reaching movements using high definition transcranial direct current stimulation (HD-tDCS) and examined changes in horizontal endpoint error when participants were subjected to anodal and cathodal stimulation. The left mIPS and PMd were functionally localized with fMRI in each participant using an interleaved center-out pointing and saccade task and mapped onto the scalp using Brainsight. We adopted a randomized, single-blind design and applied anodal and cathodal stimulation (2mA for 20 min; 3cm radius 4x1 electrode placement) during 4 separate visits scheduled at least a week apart. Each participant performed 250 baseline, stimulation, and post-stimulation memory-guided reaches starting from one of two initial hand positions (IHPs) to one of 4 briefly flashed targets (20 cm distant, 5 cm apart horizontally) while fixating on a straight-ahead cross located at the target line. Separate 2-way repeated measures ANOVAs of horizontal endpoint error difference after cathodal tDCS at each stimulation site revealed a significant IHP by target position interaction effect at the left mIPS, and significant IHP and target main effects at the left PMd. Behaviorally, these effects corresponded to IHP-dependent contractions after cathodal mIPS tDCS and IHP-independent contractions after cathodal PMd tDCS. These results suggest that the movement vector is not yet formed at the input level of mIPS, but is encoded at the input of PMd. These results also indicate that tDCS is a viable, useful method in investigating movement planning properties through temporary perturbations of the system.en_US
dc.languageenen
dc.language.isoenen_US
dc.relation.ispartofseriesCanadian thesesen
dc.rightsQueen's University's Thesis/Dissertation Non-Exclusive License for Deposit to QSpace and Library and Archives Canadaen
dc.rightsProQuest PhD and Master's Theses International Dissemination Agreementen
dc.rightsIntellectual Property Guidelines at Queen's Universityen
dc.rightsCopying and Preserving Your Thesisen
dc.rightsThis publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.en
dc.subjectHD-tDCSen_US
dc.subjectmovement planningen_US
dc.subjectPMden_US
dc.subjectreachingen_US
dc.subjectmIPSen_US
dc.titleDifferential contributions of the mIPS and PMd in the movement planning of reaches investigated through HD-tDCSen_US
dc.typethesisen_US
dc.description.restricted-thesisNeed to submit paper prior to having the thesis publicly available. A period of 6 months requested prior to having the thesis publicly available.en
dc.description.degreeMasteren
dc.contributor.supervisorBlohm, Gunnaren
dc.contributor.departmentNeuroscience Studiesen
dc.embargo.terms1825en
dc.embargo.liftdate2021-10-02


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record