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Task modulates functional connectivity networks in free viewing behavior

Seidkhani, Hossein ; Nikolaev, Andrey R LU ; Meghanathan, Radha Nila ; Pezeshk, Hamid ; Masoudi-Nejad, Ali and van Leeuwen, Cees (2017) In NeuroImage 159. p.289-301
Abstract

In free visual exploration, eye-movement is immediately followed by dynamic reconfiguration of brain functional connectivity. We studied the task-dependency of this process in a combined visual search-change detection experiment. Participants viewed two (nearly) same displays in succession. First time they had to find and remember multiple targets among distractors, so the ongoing task involved memory encoding. Second time they had to determine if a target had changed in orientation, so the ongoing task involved memory retrieval. From multichannel EEG recorded during 200 ms intervals time-locked to fixation onsets, we estimated the functional connectivity using a weighted phase lag index at the frequencies of theta, alpha, and beta... (More)

In free visual exploration, eye-movement is immediately followed by dynamic reconfiguration of brain functional connectivity. We studied the task-dependency of this process in a combined visual search-change detection experiment. Participants viewed two (nearly) same displays in succession. First time they had to find and remember multiple targets among distractors, so the ongoing task involved memory encoding. Second time they had to determine if a target had changed in orientation, so the ongoing task involved memory retrieval. From multichannel EEG recorded during 200 ms intervals time-locked to fixation onsets, we estimated the functional connectivity using a weighted phase lag index at the frequencies of theta, alpha, and beta bands, and derived global and local measures of the functional connectivity graphs. We found differences between both memory task conditions for several network measures, such as mean path length, radius, diameter, closeness and eccentricity, mainly in the alpha band. Both the local and the global measures indicated that encoding involved a more segregated mode of operation than retrieval. These differences arose immediately after fixation onset and persisted for the entire duration of the lambda complex, an evoked potential commonly associated with early visual perception. We concluded that encoding and retrieval differentially shape network configurations involved in early visual perception, affecting the way the visual input is processed at each fixation. These findings demonstrate that task requirements dynamically control the functional connectivity networks involved in early visual perception.

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author
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Adolescent, Adult, Behavior, Electroencephalography, Eye Movements/physiology, Female, Humans, Male, Memory/physiology, Nerve Net/physiology, Neural Pathways/physiology, Photic Stimulation, Visual Perception/physiology, Young Adult
in
NeuroImage
volume
159
pages
13 pages
publisher
Elsevier
external identifiers
  • scopus:85026857912
  • pmid:28782679
ISSN
1095-9572
DOI
10.1016/j.neuroimage.2017.07.066
language
English
LU publication?
no
id
609b576b-4fdf-4d1d-88ad-d91b6fd11b21
date added to LUP
2019-10-21 19:27:22
date last changed
2019-12-10 08:16:03
@article{609b576b-4fdf-4d1d-88ad-d91b6fd11b21,
  abstract     = {<p>In free visual exploration, eye-movement is immediately followed by dynamic reconfiguration of brain functional connectivity. We studied the task-dependency of this process in a combined visual search-change detection experiment. Participants viewed two (nearly) same displays in succession. First time they had to find and remember multiple targets among distractors, so the ongoing task involved memory encoding. Second time they had to determine if a target had changed in orientation, so the ongoing task involved memory retrieval. From multichannel EEG recorded during 200 ms intervals time-locked to fixation onsets, we estimated the functional connectivity using a weighted phase lag index at the frequencies of theta, alpha, and beta bands, and derived global and local measures of the functional connectivity graphs. We found differences between both memory task conditions for several network measures, such as mean path length, radius, diameter, closeness and eccentricity, mainly in the alpha band. Both the local and the global measures indicated that encoding involved a more segregated mode of operation than retrieval. These differences arose immediately after fixation onset and persisted for the entire duration of the lambda complex, an evoked potential commonly associated with early visual perception. We concluded that encoding and retrieval differentially shape network configurations involved in early visual perception, affecting the way the visual input is processed at each fixation. These findings demonstrate that task requirements dynamically control the functional connectivity networks involved in early visual perception.</p>},
  author       = {Seidkhani, Hossein and Nikolaev, Andrey R and Meghanathan, Radha Nila and Pezeshk, Hamid and Masoudi-Nejad, Ali and van Leeuwen, Cees},
  issn         = {1095-9572},
  language     = {eng},
  month        = {10},
  pages        = {289--301},
  publisher    = {Elsevier},
  series       = {NeuroImage},
  title        = {Task modulates functional connectivity networks in free viewing behavior},
  url          = {http://dx.doi.org/10.1016/j.neuroimage.2017.07.066},
  doi          = {10.1016/j.neuroimage.2017.07.066},
  volume       = {159},
  year         = {2017},
}