An fMRI investigation into the effect of preceding stimuli during visual oddball tasks

Investor logo

Warning

This publication doesn't include Faculty of Medicine. It includes Central European Institute of Technology. Official publication website can be found on muni.cz.
Authors

FAJKUS Jiří MIKL Michal SHAW Daniel Joel BRÁZDIL Milan

Year of publication 2015
Type Article in Periodical
Magazine / Source Journal of Neuroscience Methods
MU Faculty or unit

Central European Institute of Technology

Citation
Web http://ac.els-cdn.com/S0165027015001788/1-s2.0-S0165027015001788-main.pdf?_tid=9a20bf90-8dfd-11e5-b99f-00000aab0f01&acdnat=1447855785_2848590d3bb6924b3aa3be243f10167e
Doi http://dx.doi.org/10.1016/j.jneumeth.2015.05.005
Field Neurology, neurosurgery, neurosciences
Keywords fMRI; Oddball; Stimulus sequence; Target; Parametric modulation; Attention
Attached files
Description Background: This study investigates the modulatory effect of stimulus sequence on neural responses to novel stimuli. A group of 34 healthy volunteers underwent event-related functional magnetic resonance imaging while performing a three-stimulus visual oddball task, involving randomly presented frequent stimuli and two types of infrequent stimuli targets and distractors. New method: We developed a modified categorization of rare stimuli that incorporated the type of preceding rare stimulus, and analyzed the event-related functional data according to this sequence categorization; specifically, we explored hemodynamic response modulation associated with increasing rare-to-rare stimulus interval. Results: For two consecutive targets, a modulation of brain function was evident throughout posterior midline and lateral temporal cortex, while responses to targets preceded by distractors were modulated in a widely distributed fronto-parietal system. As for distractors that follow targets, brain function was modulated throughout a set of posterior brain structures. For two successive distractors, however, no significant modulation was observed, which is consistent with previous studies and our primary hypothesis. Comparison with existing methods: The addition of the aforementioned technique extends the possibilities of conventional oddball task analysis, enabling researchers to explore the effects of the whole range of rare stimuli intervals. Conclusion: This methodology can be applied to study a wide range of associated cognitive mechanisms, such as decision making, expectancy and attention. (C) 2015 Elsevier B.V. All rights reserved.
Related projects:

You are running an old browser version. We recommend updating your browser to its latest version.

More info