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Updated: Jun 10, 2026
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Paired Cisterna Magna Nanoinjection and Laser Speckle Contrast Imaging Assay to Study Cerebral Blood Flow Regulation In Vivo
Published on: July 8, 2025
Cortical neuromodulation modifies cerebral vasomotor reactivity.
Fabrizio Vernieri1, Giovanni Assenza, Paola Maggio
1Neurologia Clinica, Università Campus Bio-Medico, Via Alvaro del Portillo 200, Roma 00128, Italy. f.vernieri@unicampus.it
Stroke
|July 31, 2010
Summary
Transcranial direct current stimulation (tDCS) alters cerebral vasomotor reactivity (VMR) in a polarity-specific manner. Anodal tDCS reduced VMR, while cathodal tDCS increased it, suggesting sympathetic nervous system involvement.
Area of Science:
- Neuroscience
- Cerebrovascular Physiology
- Neuromodulation
Background:
- Cerebral vasomotor reactivity (VMR) is crucial for regulating cerebral blood flow during hypercapnia.
- The impact of transcranial direct current stimulation (tDCS) on cerebral hemodynamics, including VMR, remains under-investigated.
Purpose of the Study:
- To investigate the effects of anodal and cathodal tDCS on cerebral VMR in healthy individuals.
- To explore the potential role of the sympathetic nervous system in mediating tDCS-induced VMR changes.
Main Methods:
- Ten healthy subjects received anodal or cathodal tDCS over the left motor cortex.
- Cerebral VMR was assessed using transcranial Doppler before and after tDCS.
- Heart rate variability, specifically normalized low-frequency band power reactivity (LFN(react)), was measured as a marker of sympathetic activation.
Main Results:
- tDCS demonstrated a polarity-specific effect on both VMR (P=0.0001) and sympathetic activation markers (P=0.001).
- Anodal tDCS bilaterally decreased VMR and increased LFN(react).
- Cathodal tDCS bilaterally increased VMR and decreased LFN(react).
Conclusions:
- Transcranial direct current stimulation significantly modifies cerebral VMR.
- Observed VMR changes correlate with heart rate variability alterations, suggesting sympathetic nervous system modulation.
- Further research is warranted to elucidate the precise mechanisms linking tDCS, sympathetic activity, and bihemispheric VMR regulation.
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