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Updated: May 15, 2026
Brain State-dependent Brain Stimulation with Real-time Electroencephalography-Triggered Transcranial Magnetic Stimulation
Published on: August 20, 2019
Brain state-triggered stimulus delivery: An efficient tool for probing ongoing brain activity.
M L Andermann1, J Kauramäki, T Palomäki
1Department of Biomedical Engineering and Computational Science, Helsinki University of Technology, Helsinki, Finland ; Brain Research Unit, Low Temperature Laboratory, Helsinki University of Technology, Helsinki, Finland ; Department of Neuroscience, Brown University, Providence, MA, USA.
Understanding ongoing brain activity is key to perception. This study introduces a novel method to trigger stimuli based on brain states, revealing how neural bias influences auditory detection and enabling efficient study of brain activity patterns.
Area of Science:
- Systems Neuroscience
- Cognitive Neuroscience
- Human Perception
Background:
- Variability in ongoing brain activity preceding sensory stimuli significantly impacts subsequent perception.
- Studying specific brain states is challenging due to their infrequent and random occurrence relative to stimulus presentation.
Purpose of the Study:
- To investigate the relationship between pre-stimulus neural activity patterns and perceptual outcomes.
- To develop and validate a novel method for aligning stimulus presentation with specific, dynamically identified brain states.
Main Methods:
- Developed a novel online method to identify and track spatiotemporal patterns of ongoing brain activity (electroencephalography).
- Implemented a brain-state triggered stimulus delivery system to present auditory stimuli during specific neural states.
- Analyzed the influence of pre-target neural bias fluctuations on auditory selective listening performance.
Main Results:
- Pre-target fluctuations in neural bias, identified online, significantly influenced the detection of target sounds.
- The influence of neural bias was observed both within and across individual trials.
- The brain-state triggered approach allowed for the study of neural activity preceding perception.
Conclusions:
- Brain state-triggered stimulus delivery is an effective method for studying the influence of ongoing neural activity on perception.
- This technique facilitates statistically tractable investigations into rare neural patterns and their impact on behavior.
- The findings advance our understanding of how dynamic neural states shape sensory processing and perception.
