Experimental brain research can benefit enormously from pain-free and non-invasive stimulation options. As such, TMS can induce a temporary functional disturbance in a focal area of the cortex. This lesional effect can be characterized by psychophysical measurements and lead to important conclusions about the functional relevance of the stimulated area of the cortex.
The high temporal resolution of electroencephalography (EEG) permits the direct derivation of brain activity triggered by TMS. In addition to the performance of TMS and EEG at separate times (offline method), the simultaneous use of TMS and EEG (online method) can provide an especially unique opportunity to investigate corticocortical connections.
- Interactive method: Analysis of TMS effects on functional networks during cognitive tasks.
- Inductive method: Evaluation of cortical reactivity and connectivity by measuring transcallosal evoked potentials (TEP).
- Rhythmic method: Monitoring of the influence of TMS stimulation on oscillatory brain activity to understand the causal relationships between cortical rhythm and perceptual, cognitive or motor processes.
Major considerations and solutions:
Induction of mains noise into electrodes and leads
Advanced shielding of stimulator to avoid interferences.
Precise and reliable timing
Trigger in/out must be without jitter.
Integration into existing EEG-labs
Various possibilities to control the stimulation with existing equipment.
Future proof equipment
Possibility to upgrade stimulation hard- and software in order to follow future