Chronometric TMS-fMRI: Timing & Brain Networks

Chronometric TMS-fMRI tests how the timing of a perturbation changes a brain network’s response.

We apply TMS at defined moments relative to a task event, then compare the resulting local and remote BOLD responses. Keeping the target and stimulation parameters controlled lets us ask how cognitive context changes network susceptibility.

Observe. Perturb. Time.Brain regions fluctuate together. A targeted perturbation tests network responses. Task-relative timing adds another experimental dimension.

Working memory and language

Our working-memory studies use N-back tasks to establish reproducible cognitive states. In language experiments, stimulation at different moments during picture naming probes the changing contribution of temporal and frontal regions.

Watch the original EPICONN animation · 42 seconds

Original animation from Martin Tik’s EPICONN presentation. Signals and network responses are schematic, not participant data.

Precise perturbation, haemodynamic readout

Chronometry does not turn fMRI into a millisecond recording of neural activity. The precise variable is when we stimulate; the measured outcome is the subsequent BOLD response. We interpret timing effects through controlled comparisons and behavioural measures.

Chronometric TMS-fMRI and state-dependent sgACC effects, 2024 ↗

Chronometric interleaved TMS-fMRI of speech production ↗

Task state and stimulation timing

Rest, 0-back and 2-back task conditions, with stimulation at minus 250 or plus 150 milliseconds — Experimental timing in our working-memory paradigm. The effective/ineffective labels refer to network engagement in this experimental comparison, not treatment efficacy. Image: Tik Group / High Field MR Center, MedUni Vienna.

Chronometric TMS-fMRI in Vienna

Meet Martin Tik and the research team developing these methods at MedUni Vienna. Explore related language research, EPICONN and publications.

Student projects, research interests and collaborations in Vienna →