Related Experiment Video
Updated: May 13, 2026

Extracting Visual Evoked Potentials from EEG Data Recorded During fMRI-guided Transcranial Magnetic Stimulation
Published on: May 12, 2014
Investigating high- and low-frequency neuro-cardiac-guided TMS for probing the frontal vagal pathway
Manreena Kaur1, Jessica A Michael2, Kate E Hoy2
1Epworth Centre for Innovation in Mental Health, Epworth HealthCare and Department of Psychiatry, Monash University, Camberwell, Victoria, Australia; Neuroscience Research Australia, Sydney, Australia; School of Psychiatry, University of New South Wales, Sydney Australia.
Background:
Investigating approaches for determining a functionally meaningful dorsolateral prefrontal cortex (DLPFC) stimulation site is imperative for optimising repetitive transcranial magnetic stimulation (rTMS) response rates for treatment-resistant depression. One proposed approach is neuro-cardiac-guided rTMS (NCG-TMS) in which high frequency rTMS is applied to the DLPFC to determine the site of greatest heart rate deceleration. This site is thought to index a frontal-vagal autonomic pathway that intersects a key pathway believed to underlie rTMS response.
Objective:
We aimed to independently replicate previous findings of high-frequency NCG-TMS and extend it to evaluate the use of low-frequency rTMS for NCG-TMS.
Methods:
Twenty healthy participants (13 female; aged 38.6 ± 13.9) underwent NCG-TMS on frontal, fronto-central (active) and central (control) sites. For high-frequency NCG-TMS, three 5 s trains of 10 Hz were provided at each left hemisphere site. For low-frequency NCG-TMS, 60 s trains of 1 Hz were applied to left and right hemispheres and heart rate and heart rate variability outcome measures were analysed.
Results:
For high-frequency NCG-TMS, heart rate deceleration was observed at the left frontal compared with the central site. For low-frequency NCG-TMS, accelerated heart rate was found at the right frontal compared with central sites. No other site differences were observed.
Conclusion:
Opposite patterns of heart rate activity were found for high- and low-frequency NCG-TMS. The high-frequency NCG-TMS data replicate previous findings and support further investigations on the clinical utility of NCG-TMS for optimising rTMS site localisation. Further work assessing the value of low-frequency NCG-TMS for rTMS site localisation is warranted.
Related Concept Videos
Hydroboration-Oxidation of Alkenes
Preparation of Alcohols via Addition Reactions
The acid-catalyzed addition of water to the double bond of alkenes is a large-scale industrial method used to synthesize low-molecular-weight alcohols. An acidic atmosphere is required to allow the hydrogen in the water molecule to act as an electrophile and attack the double bond in an alkene. The addition of a proton to the double bond creates a carbocation intermediate. The proton preferentially bonds to the less substituted end of the double bond to create a more stable carbocation...
Acid-Catalyzed Dehydration of Alcohols to Alkenes
Oxidation of Alcohols
The process of oxidation in a chemical reaction is observed in any of the three forms:
Preparation of Aldehydes and Ketones from Alcohols, Alkenes, and Alkynes
Reactions of Aldehydes and Ketones: Baeyer–Villiger Oxidation
The carbonyl center is activated by...

