Not logged in.

Contribution Details

Type Journal Article
Scope Discipline-based scholarship
Title Caffeine enhances frontal relative negativity of slow brain potentials in a task-free experimental setup.
Organization Unit
  • Contribution from another University/Organization than University of Zurich
Authors
  • Carolina Murd
  • Jaan Aru
  • Mari Hiio
  • Iiris Luiga
  • Talis Bachmann
Item Subtype Original Work
Refereed Yes
Status Published in final form
Language
  • English
Journal Title Brain research bulletin
Geographical Reach international
Volume 82
Number 1-2
Page Range 39 - 45
Date 2010
Abstract Text State dependent effects on brain processes are difficult to study due to the task-related confounds. Even in simple task environments external stimuli inevitably interact with dynamically changing states of the brain. Psychopharmacological manipulation and transcranial magnetic stimulation can be used independently of variations in subject's experimental task and environmental stimulation. Our aim was to show the investigative potential of combining these two methods for studying the effects of the state of the brain on the dynamics of task-free evoked brain activity. Caffeine was used for inducing higher arousal state and transcranial magnetic stimulation was used to evoke widespread bioelectrical responses of the brain. Occipitally delivered magnetic pulses caused increased global negativity of the brain potentials, but no speed-up of brain potentials when caffeine was administered. The relative negativization effect was most clearly expressed in slow potentials and as measured from frontal and parietal electrodes. This study shows how the causal effects of brain states on neural processes can be studied without the confounding influence of experimental task and stimuli.
Digital Object Identifier 10.1016/j.brainresbull.2010.01.013
PubMed ID 20123003
Export BibTeX