Wireless Optogenetics for Freely Moving Animals
Teleopto Wireless Optogenetics joins wireless LED light sources with implantable optic fibers.
The Wireless Optogenetics System includes a precise remote control. Which provides researchers with a turnkey stimulation system for mice, rats, and other small animals.
- Receivers (head-mounted) are very small and lightweight.
- Used with mice, rats, and marmosets.
- Remote control transmits the stimulation signal to the receiver by infrared.
- Easy scaleup to many animals.
Our lab has used the wireless Teleopto system daily for the last two years and we have been extremely pleased with our experience. We have been impressed by how readily available the staff at Amuza have been to assist with any questions we’ve had and their enthusiasm towards creating custom parts to meet the needs of our unique experiments. Based on our experiences with the Teleopto system, we highly recommend it to labs interested in initiating optogenetics experiments or transitioning from wired optogenetic systems.
Over the past 15 years, optogenetics has revolutionized the way neuroscientists interrogate neural circuits. Allowing researchers to stimulate and/or inhibit neurons at a precise time and place.
How exactly does in vivo optogenetics work?
In in vivo optogenetics, fiber optic cables are used to bring the light from a laser or LED light source to a target region in the brain of a mouse, rat, or other research animals. While the light source is traditionally stationary, the addition of a rotary joint to the fiber optic cable can allow the animal some freedom of movement within small environments such as operant chambers. During optogenetic experiments, stimulation and inhibition can be triggered directly by the animal’s behavior. For example, nose pokes, lever presses, and animal location (determined by video tracking software) have all been used to trigger optogenetic stimulation. Stimulation and inhibition can also be used during conditioning sessions before behavioral testing. In these ways in vivo optogenetics can both inform and be controlled by behavioral and electrophysiological testing.
Teleopto Wireless Optogenetics takes in vivo optogenetics one step further: the LED light source is worn externally by the mouse or rat. Wireless communication allows complete freedom of movement in large complex environments, allowing optogenetics to also be used in large open field and maze experiments. A short optic fiber brings the light from the LED to the target region of the brain, keeping the heat generated by the LED outside of the animal. Wireless optogenetics also improves data from video tracking software by removing motion artifacts frequently caused by moving fiber optic cables.
Wireless Optogenetics Starter kits contain the core components of Teleopto:
Teleopto Starter Kit, TeleSS:
1 each of Remote, Receiver (specify the type), Emitter, Charger, Stereotaxic Adapter, Two Channel Trigger Cable, and 3x LED fiber optics (specify).
Teleopto Starter Kit 2 channel pulse, TeleSS 2Ch:
1 each of Remote, 2 ch pulse Receiver (specify the size), Emitter, Charger, Holder, Two Channel Trigger Cable, and 3x LED fiber optics (specify).
Lightweight Rechargeable Receivers
Teleopto’s lightweight receivers and bright LEDs provide up to 13 mW of light to the tip of an attached optic fiber. 1, 2, and 3-gram receivers are available for stimulation of single locations as well as dual (bilateral) locations. We recommend 1 g and 2 g receivers for optogenetic stimulation of mice and 2 grams and larger receivers for optogenetic stimulation of rats and larger animals.
2 channel pulse receivers
The new 2 channel pulse receivers are available in 1 g, 2 g, and 3 g sizes. As with our original pulse receivers, LEDs are ON while the remote is receiving a TTL pulse (or a trigger button is being pressed), and OFF in the absence of a pulse.
2 channel pulse receivers can be used in several different ways:
- With 2 color LED fiber-optics for stimulation and inhibition at a single site
- With bilateral implants, allowing independent control of each side.
- With two single-channel receivers (custom item, please inquire). This allows independent control of the two receivers, mounted at different sites or on different animals.
One limitation of the 2 channel pulse receivers is that only one channel can be activated at a time – both channels cannot be ON simultaneously.
Interchangeable LED Optic Fibers
Each unit comprises a three-prong electrical connector, encapsulated LED, and implantable optical fiber. The LED can be blue, green, or yellow.
Single optic fiber: lightweight and robust enough to be inserted without a guide cannula.
LED probe without optic fiber: Flat window for brain surface stimulation.
Two colors LED optic fiber: Two independently controlled LEDs are attached to two 250 μm fibers bundled together.
Bilateral LED optic fiber: for bilateral stimulation.
Two-color Bilateral LED optic fiber: for bilateral stimulation and inhibition.
LED fiber optic Cannula: For stimulation via implantable cannula.
Fiber length, fiber diameter, and the distance between the bilateral fibers can all be made to specification. Please ask about custom LED colors.
IR Remote Control
The remote control allows direct control by push buttons for two separate channels. It also allows two-channel control by TTL pulses from programmable stimulators and pulse generators.
Two-Channel Pulse Generator
The STO two-channel pulse generator delivers pulse trains to the Teleopto remote control and also the LAD-1 LED array driver. Pulse trains can be triggered manually or by 5V TTL pulses. TTL pulses can be generated by many types of behavioral test equipment, ask us if you are unsure about compatibility.
The Telehub allows a single remote control to communicate with receivers in up to six operant chambers or other optically isolated environments.
Long range infrared emitter
Dummy receivers (for conditioning)
Using loss-and gain-of-function approaches to target amygdala-projecting serotonergic neurons in the dorsal raphe nucleus that enhance anxiety-related and conditioned fear behaviors.Bernabe, C. S., Caliman, I. F., Truitt, W. A., Molosh, A. I., Lowry, C. A., Hay-Schmidt, A., … & Johnson, P. L.
(2020). Journal of Psychopharmacology, 0269881119900981.
Prefrontal parvalbumin interneurons require juvenile social experience to establish adult social behavior.
Bicks, L. K., Yamamuro, K., Flanigan, M. E., Kim, J. M., Kato, D., Lucas, E. K., … & Norman, K. J.
(2020). Nature Communications, 11(1), 1-15.
REM sleep–active MCH neurons are involved in forgetting hippocampus-dependent memories.
Izawa, S., Chowdhury, S., Miyazaki, T., Mukai, Y., Ono, D., Inoue, R., … & Terao, A.
(2019) Science, 365(6459), 1308-1313.
SatB2-Expressing Neurons in the Parabrachial Nucleus Encode Sweet Taste.
Fu, O., Iwai, Y., Kondoh, K., Misaka, T., Minokoshi, Y., & Nakajima, K. I.
(2019). Cell reports, 27(6), 1650-1656.
Correlative study using structural MRI and super-resolution microscopy to detect structural alterations induced by long-term optogenetic stimulation of striatal medium spiny neurons.
Abe, Y., Komaki, Y., Seki, F., Shibata, S., Okano, H., & Tanaka, K. F.
(2019). Neurochemistry international, 125, 163-174.
For a complete list of publications visit this page.
Frequently Asked Questions
How bright does light have to be for optogenetics?
The most commonly used opsin (ChR2) requires approximately 1 mW/mm2 for activation. However, ultra-sensitive opsins such as SSFO and SOUL can be activated with as little as 20 μW/mm2.
How far does light penetrate when used for optogenetics? How large an area can be stimulated or silenced by in vivo optogenetics?
This depends strongly upon wavelength: blue light (~470 nM) is rapidly absorbed by brain tissue: light intensity might decrease roughly 90% within 1 mm from the tip of an implanted fiber. Increasing the intensity of blue light to compensate can lead to increased photobleaching, artifacts, and tissue damage. This makes it difficult to usefully activate ChR2 more than 1 mm from the tip of an optical fiber. Red light penetrates much further into brain tissue, making it more appropriate for large and deep targets in the brain. Karl Deisseroth’s website has a calculator based on direct measurements of 473, 561, and 630 nm light in mammalian brain tissue.
Why is light delivered in pulses for optogenetics?
Many opsins, such as variants of ChR2, will quickly be inactivated when exposed to bright light continuously. This inactivation can be temporary or permanent (photobleaching). Long periods of exposure to blue light can also silence some subpopulations of neurons expressing ChR2 via depolarization blocking: (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3904216/)
Where can I find out more about how to plan my optogenetics experiment?
Please see our Optogenetics Resource Guide, where we have shared some of the many resources our customers have found useful for planning their optogenetics projects.
How long will it take for me to receive my order?
How wide is the cone of light produced by the fiber optic implant?
How close together can the two fibers of a bilateral LED implant be?
0.9 mm, center to center. 1.3 mm for 500 µm fibers.
This system is almost perfect for us, but would be more ideal with customizable options - can you tailor it to meet our specific needs?
The receivers and LED-Fiber optics can be customized extensively, often without additional costs. Examples include higher output receivers, different configurations to allow integration with headstages, different LED colors, etc. Please let us know what you need and we can work with you.
Which receiver should I choose, pulse type,continuous type, or OptoFlash?
In general, we recommend the pulse type receiver for most experiments, because of
many advantages (higher output power, better time resolution, easier control, etc.). However, we recommend the continuous type receiver in the following cases:
- In an environment with hiding places, like mouse tunnels, houses, or bedding for nesting.
Teleopto uses infrared signals for communication, so if animals hide under opaque materials
communications can fail. In continuous type receivers, so long as the “turn on” pulse is sent while there is no obstruction between the emitter and the receiver, the stimulation will continue when the receiver is blocked.
- For illuminating very long term (several seconds to several minutes without interruption).
The light power of continuous receivers is typically less than 30% that of corresponding pulse type receivers. This is to prevent overheating due to continuous high current.
Optoflash is preprogrammed permanently at the factory with the pulse train of your choice. It has significantly longer battery life than our receivers, but there is no control other than the on/off switch.
The receiver flashes when I touch it. Also, it flashes when I bring it close to fluorescent lights or electric power cords. Is this normal?
Yes. There is a technical challenge for completely eliminating such artifacts. Those can be reduced by decreasing sensitivity of the sensor, but it’s trade-off with transmission range. We tuned the sensitivity with which it doesn’t flash on animal’s head in typical lab environment. If you see artifact in your experimental setup, please keep enough distance from fluorescent lights. The new communication protocol for the 2ch pulse receiver resulted in higher resistibility for environmental noise. For noisy environments, we can even provide 1ch version pulse receivers using this protocol. Please contact us for more details.
How long will a wireless receiver keep powering the LED before the rechargeable battery is exhausted?
What is the standby time for the receivers?
For the new 2g (2 gram) receiver it is 28 hrs. For the original 2g receivers it is 24 hrs.
How fast can the LED fiber optics be pulsed?
The maximum tested rate is 1000 Hz in P (Pulse) mode. The maximum rate in 2P (2 channel pulse) mode is approximately 450 Hz (total combined rate for both channels).
Can the two LEDs on a bilateral or two color LED fiber optic be pulsed independently?
2 channel receivers can control each LED separately, but both LEDs can not be lit simultaneously.
I have a two channel receiver, I would like to do simultaneous (both sides illuminated at the same time) bilateral stimulation. How do we do this?
What if I need a bilateral probe, but can’t implant the two optic fibers in parallel?
The bilateral fiber optic is also available with the LEDs attached to the receiver by short cables, allowing each optic fiber to be implanted independently.
How long is the latency between a trigger pulse and the receiver output? What is the time resolution for pulses?
There is a 240 µsecond latency for activating the original pulse receiver, 25 ms for continuous receivers, and 2050 µs for the new 2 channel pulse receiver. The time resolution is 150 µs.
How many animals can one Remote Control stimulate at once?
The emitters are limited only by range and line of sight, and will pulse all of the receivers that can “see” an emitter. We offer a wide beam emitter that will pulse all receivers within 3 m, and small emitters meant to illuminate individual cages or sections of a maze. With some limitations, one remote can send different pulse trains to 2 different animals.
How deep can the fiber optics be implanted?
Teleopto fiber optics can be made to any length you specify. The acrylic fiber is flexible, so a guide cannula may be appropriate for deep implants in larger animals.
Can the LED-fiber optics be reused?
Users following the implantation and removal instructions in our manual have used the same LED-fiber optics up to 5 times.
What wavelength do the IR emitters and receivers use? Can the emitters be used to transmit signals through the plastic walls of a chamber?
Does the clip type emitter have to be used with a Telehub? Does the wide area emitter have to be plugged directly into the remote control?
Both emitter types can either be plugged directly into the remote or via the Telehub.
What if I need more light power?
How do I protect the 3 pin connector for the LED after implantation?
Can Teleopto be combined with electrophysiology headstages?
Yes. Users sometimes see stimulation artifacts at the onset of optical stimulation, but the amplitude is smaller than the artifacts seen with conventional electrical stimulation. We don’t see any other interference, by, say, the transmission signal, etc.
How do I sterilize the LED Fiber optic before implantation?
Quickly wiping the implant with 70% ethanol is recommended.
What is a typical pulse train for use with CHR2?