Post written by Anne Verlangieri, MS IV at Drexel University College of Medicine, Class of 2014
Step aside Obi-Wan Kenobi, this is not the mind control you’re looking for. A recent study conducted by researchers at Harvard University has demonstrated a method for non-invasive, functional linkage of brain activity from human volunteers and Sprague-Dawley rats. The method, dubbed brain-to-brain interface (BBI), utilizes electroencephalographic steady-state-visual-evoked potentials (SSVEP) and transcranial focused ultrasound (FUS). The goal of the process is to allow human volunteers to use visual stimuli to elicit motor responses from the tail’s of rats. To understand how BBI works, we’ll need some background on the SSVEP and FUS segments.
Numerous neurophysiological studies have shown that there is increased neural activity elicited by a visual stimulus with directed attention. In other words, observer attention on a specific visual stimuli is more important that the stimulus itself, in producing measurable spikes in neural activity. SSVEP utilizes EEG based brain-to-computer interfacing (BCI), to take advantage of this idea. In practice, a human volunteer is equipped with an EEG and instructed to gaze on a designated visual stimulus. The EEG reads the pre-synchronized neural activity, linking the volunteer’s brain with an SSVEP computer.
Transcanial focused ultrasound has been used clinically as a non-invasive therapy for certain brain disorders, (ex. Deep brain stimulation in Parkinson’s Disease) as well as thermal ablation of brain tumors. This technology allows for region-specific brain stimulation, and when set at low acoustic energy, has been shown to excite or suppress rabbit motor/visual cortices; effectively creating a computer-to-brain interface (CBI).
How BBI works
(Figure 1. The schematics of the implemented brain-to-brain interface (BBI). The implementation consists of steady-state visual evoked potential (SSVEP)-based brain-to-computer interface (BCI: on the left column) and focused ultrasound (FUS)-based computer-to-brain interface (CBI) segments (on the right column). [doi:10.1371/journal.pone.0060410.g001]
The set-up shown in figure 1, demonstrates how SSVEP and FUS are utilized to link the human volunteer and with the rat’s brain. The volunteer is instructed to look at a specific visual target, creating an increase in EEG bandwidth corresponding to that specific visual stimulation frequency. A SSVEP detector reads the increase in EEG bandwidth and triggers the activation’s of the FUS, which stimulates specific motor area’s of the rats brain, resulting in a twitch in the rat’s tail. Here’s the experiment in action:
What can we do with this technology?
Certainly, the possible applications of BBI are far reaching. The studies authors proposed that this technology could one day be used for indirect sensory/somatomotor communication allowing an increased degree of understanding during verbal communications between speaker and listener.
Other’s have suggested “Hive mind” like problem solving, via a linked think-tank. And of course there is the potential for further human-to-animal interaction; pet owners would jump at the chance to know just what Fido is thinking.
Another recent study used this technology for one student to control another student playing a video game at a remote location.
Regardless of the application, it will be important to look at the legal, ethical, and privacy concerns involving technology that has the potential to transmit thought from one individual to another. The study is free to download and read here.