Research

Vision

The brain is a complex electrochemical system, home to a spectrum of electrical signals. My main research interest is to understand how the brain interacts with electromagnetic influences either when it is exposed to ambient fields or when it is intentionally perturbed by fields for therapeutic purposes. My research is multidisciplinary, sitting at the interface of Neuroscience, Engineering, and Medicine, applying a wide range of tools to record and/or influence neural activity.  Our approach constitutes a combination of basic and translational sciences.

Interactions of electromagnetic fields with neural activity

We are interested in the evaluation of the effects of applied electromagnetic fields, in various forms (i.e., electrical current, magnetic fields, electric fields, microwaves, etc.),  and across different frequencies (from DC to millimeter-waves) on the brain and its activity. To this end, we apply different methods to monitor neural activity (at single-cell and network levels) and whole-brain functional connectivity. 

One particular direction that I will pursue at the being of my independent career is the development of Transcranial Radio Frequency Stimulation (TRFS), a non-invasive brain stimulation method that I have been establishing during my postdoctoral work, towards its clinical translation. To that end, my lab will 1) try to further characterize and better understand the effects of TRFS on neural activity, 2) study the translational effects of TRFS on rodent models of brain disorders, and 3) design, prepare, and execute first TRFS clinical trials.  

Past & Ongoing Projects

Effects of continuous-wave RF energy radiation on neural activity 

Whether non-thermal RF energy exposure can affect ongoing neural activity or not has been the core of a several-decades-long scientific debate.  We studied the effects of continuous-wave RF radiation on neural activity monitored by electrophysiology and 1-photon calcium imaging. Our electrophysiological recordings showed a variety of significant changes in neural activity due to RF energy exposure.  Our metal implant-free RF interference-free imaging results, however, demonstrated that RF energy exposure, inducing specific absorption rates (SAR) several folds higher than allowed by regulatory limits, does not affect neural activity in a significant manner. 

Read more here.  

Direct measurement of RF electric fields in-vivo  

To accurately assess the strength of the absorbed RF energy in exposed mice brains, we developed a method for direct measurement of electric fields in-vivo using a  Bismuth Silicon Oxide (BSO) crystal sensor. This method can be used in dosimetry studies for a diverse set of applications incorporating the interaction of RF energy and biological tissue. 

Read more here.  

An open-source versatile 3D-print design for animal conditioning in rodent brain-imaging experiments 

We have studied the effect of RF energy exposure on whole brain activity by functional Magnetic Resonance Imaging (fMRI) in mice. To do that, we developed a 3D-print design for optimal animal conditioning and experimental set-up. We extended the functionality of this design to include multi-modal imaging and host both mice and rats and made it freely available to the public with open source.  We also designed a compatible heating and cooling system to control animals' body and brain temperature.

Read more here and here.   

Non-invasive neuromodulation by Transcranial Radio Frequency Stimulation (TRFS)

RF exposure can induce temperature rise in the biological tissue such as the brain. These temperature changes can affect the ongoing activity of neurons. When the thermal changes in the brain are controlled within a safe range, RF can be used as a non-invasive neuromodulation tool. In an ongoing study, we are working on establishing an RF stimulation paradigm to demonstrate the proof-of-concept for this method using a combination of RF-artifact-free (and metal-free) neural recordings, i.e., fMRI and optical imaging. 

Tools & Techniques

Large-scale electrophysiology

We use silicon probes to record neural activity (i.e. brain oscillations and spiking activity of hundreds of single neurons) in several brain regions of behaving (freely-moving and/or head-fixed) rodents. 

1-Photon calcium imaging with Miniscope

Using miniature head-mounted 1-photon imaging endoscopes (UCLA Miniscope) we monitor the ongoing neuronal activity of several hundreds of single neurons in different brain regions in behaving (freely moving or head-fixed) rodents. We have also developed a modified fiber-coupled version to perform artifact-free neural recording in RF energy-exposed head-fixed mice. 

Fiber photometry

We employ fiber-photometry to measure the collective activity of ensembles of cells and/or changes of different types of neuromodulators in behaving rodents.    

Multi-modal small animal brain imaging

Using our multi-modal rodent conditioning platform, we perform different types of whole-brain imaging including Magntic Resonance Imaging (MRI), functional MRI (fMRI), Pet/CT, etc. These methods allow us to assess structural, functional, and metabolic information about rodents brain in anesthetized or awake state.   

Data analysis

We use costume-made and/or publicly available computational code to perform analytical calculations on various types of measured data (from physiological variables to large-scale neural activity). 

Numerical simulation

We perform physics-based numerical simulations to model different realistic scenarios and study various parameters under those conditions.  

3D print designs for experimentation

3D print designs are fast, easy, low-cost, and incredibly efficient solutions for filling the gaps in experimental design where commercially available parts fail to satisfy the needs.  Our designs are open-source and we are happy to share them with the scientific community. They can be found here.