Cortical activity preceding vertical saccades: A MEG study

Tzelepi, A; Laskaris, N; Amditis, A; Kapoula, Z

dc.contributor.author	Tzelepi, A	en
dc.contributor.author	Laskaris, N	en
dc.contributor.author	Amditis, A	en
dc.contributor.author	Kapoula, Z	en
dc.date.accessioned	2014-03-01T01:33:05Z
dc.date.available	2014-03-01T01:33:05Z
dc.date.issued	2010	en
dc.identifier.issn	0006-8993	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/20309
dc.subject	Exploratory data analysis	en
dc.subject	Motor preparation	en
dc.subject	Spatial attention	en
dc.subject	Vertical asymmetry	en
dc.subject.classification	Neurosciences	en
dc.subject.other	adult	en
dc.subject.other	article	en
dc.subject.other	association	en
dc.subject.other	brain asymmetry	en
dc.subject.other	female	en
dc.subject.other	human	en
dc.subject.other	latent period	en
dc.subject.other	male	en
dc.subject.other	normal human	en
dc.subject.other	oculography	en
dc.subject.other	priority journal	en
dc.subject.other	saccadic eye movement	en
dc.subject.other	visual field	en
dc.subject.other	Adult	en
dc.subject.other	Brain Mapping	en
dc.subject.other	Female	en
dc.subject.other	Humans	en
dc.subject.other	Magnetoencephalography	en
dc.subject.other	Male	en
dc.subject.other	Saccades	en
dc.subject.other	Signal Processing, Computer-Assisted	en
dc.subject.other	Visual Cortex	en
dc.subject.other	Young Adult	en
dc.title	Cortical activity preceding vertical saccades: A MEG study	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.brainres.2010.01.002	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.brainres.2010.01.002	en
heal.language	English	en
heal.publicationDate	2010	en
heal.abstract	Previous studies have shown that upward saccade latencies are faster than downward saccade latencies in certain tasks. This asymmetry does not appear to represent a general main effect of the visual, or the vertical oculomotor system. In this study we examined the cortical activity underlying this latency asymmetry. We used MEG to assess cortical activity related to horizontal and vertical saccade preparation, and eye movement recordings to assess saccade latencies in a modified delay task. The reconstructed cortical activity was examined with respect to the onset of the target stimulus and the onset of the saccade. Upward saccades were faster than downward saccades, in agreement with previous studies. Although to a large extent, horizontal and vertical targets activated similar areas, there were also some differences. The earlier difference was found 100-150 ms after target onset over the right supramarginal gyrus when subjects attended to location-cues. Down cues activated this area faster than up cues. Moreover, cue-related activity was stronger over the left frontal cortex for up than down cues. In contrast, saccade-related activity over the same area was stronger when preceding downward than upward saccades. The results suggest that stimuli in the upper and lower visual field may have different impacts on accessing networks related to visual attention and motor preparation resulting in different behavioral asymmetries. (C) 2010 Elsevier B.V. All rights reserved.	en
heal.publisher	ELSEVIER SCIENCE BV	en
heal.journalName	Brain Research	en
dc.identifier.doi	10.1016/j.brainres.2010.01.002	en
dc.identifier.isi	ISI:000276120800012	en
dc.identifier.volume	1321	en
dc.identifier.spage	105	en
dc.identifier.epage	116	en